Primer for Current Melanoma Treatments - New and Improved Version 2022!!!!

Originally posted in 2017, sadly, this primer has needed little in the way of updates since.  Still, there have been a few FDA approvals, meds I didn't include in the first rendition, and some news in the research so it is getting a reboot. Initially created to save re-writes for those in need, I still answer melanoma questions on boards or via email at least every other week, but want to emphasize that this is not an all inclusive listing.  Rather, this is a basic guide to use in starting your research or discussions with your provider regarding melanoma care.  As recently, as 2010, NONE of the current, most effective treatments for melanoma were FDA approved.  Since then, doctors have become more knowledgeable about consistently offering and better skilled in managing these treatments.  Still, it is essential that you be seen by an oncologist who specializes in, or at the very least, has treated many patients with melanoma.  Sometimes a picture is worth a thousand words ~ 

Here we go:

SURGERY

Surgery remains a good choice for many melanoma patients.  Clearly this is the case for a new cutaneous lesion.  Surgery results in an immediate decrease in your tumor burden - almost always a good thing.  However, with data showing good results in NEO-adjuvant treatment, the possibility of using intralesional therapy, or if you are looking for a clinical trial, there are times when measurable disease is needed, so a discussion of these things before surgery is important.  However, for patients with advanced disease decreasing tumor burden through surgery remains an important option for increased survival.  This 2019 report addresses some of the conundrum:  Cut it out!!! Prolonged overall survival following metastasectomy in Stage IV melanoma 

RADIATION

Radiation, when combined with immunotherapy or targeted therapy, can be a very good treatment option for melanoma.  Together, radiation and systemic therapy can illicit responses that are greater than either treatment used as a single agent.  However, targeted radiation (SRS - stereotactic radiation or Gamma Knife) is the most effective whether you are talking about brain tumors or lesions in the body.  We have learned that whole brain radiation (WBR) is not the most effective way to treat melanoma and can lead to debilitation.  While there are those who must avail themselves of this treatment due to extreme circumstances, it should not be the first recommendation right out of the box for those with brain tumors.  Even multiple brain mets can be treated simultaneously with SRS.   Here are zillions of reports regarding the effectiveness of using radiation WITH immunotherapy: Radiation WITH immunotherapy  Here is a report from 2019 regarding the use of radiation prior to targeted therapy:  Better melanoma results with radiation BEFORE BRAFi (at least in this report)

IMMUNOTHERAPY

These are treatments that push our immune systems into action.  Side effects (as you might imagine) are usually related to an 'over activation' of the immune system.  Common side effects include - fatigue, rashes, joint pain.  More complicated side effects are inflammation of the lungs (pneumonitis) and colon (colitis) with difficulty breathing and wheeze or diarrhea and abdominal discomfort, respectively.  Patients can experience problems with thyroid function and other glands of the endocrine system.  Responses take time.  Experts are known to advise other docs to be 'patient with the patient!'  Immunotherapy works best with the lowest tumor burden.

Old school immunotherapy

Interferon

Discovered in 1957, interferons are a type of signaling proteins released by cells in response to viruses, bacteria, parasites, and tumors that help rally the immune response of the body against these invaders. In the early 1980's researchers and pharma were finally able to produce interferon for use as a medical therapy. There are many forms, used in treating various conditions (some more effectively than others) from multiple sclerosis to leukemia to melanoma. Often given as subcutaneous injections (though there are eye drops and inhalation forms), interferon causes significant side effects with fatigue, flu-like symptoms, hair loss, pain, depression and increased risk of infection due to neutropenia (decreased white cells) being common. Unfortunately, we have learned that in melanoma, interferon has a clinically insignificant effect on progression free survival as well as overall survival.

IL-2 (Interleukin 2) also known as aldesleukin, proleukin, and/or sylatron

Similarly, IL-2 is a signaling molecule that directs the actions of white blood cells in getting rid of invaders. Isolated in 1979, by the early 80's pharma (Ceta, Amgen, Roche) were in a mad dash to get a drug to market. It was FDA approved in 1992. It has been used in the treatment of HIV, renal cell carcinoma, and melanoma. Though it can be injected subcutaneously on an outpatient basis, in melanoma it is most often given in an IV infusion, with side effects (extreme swelling, rash/peeling skin, hallucinations, among other horrors) such that patients must be in the hospital, in an intensive care setting, for infusions that are given every 8 hours for up to 15 doses or as the patient can tolerate. It is also used in a low dose regimen with old school TIL therapy as a way to jump start the immune system after chemo has been given to eradicate existing regulatory T cells and new T cells grown from the patient's tumor have been infused.  See this 2021 report:  TIL - A report out of ASCO 2021 and incredible words from one of Melanoma's Most Fearless and Inspiring Leaders  It is also being studied as an intralesional (see below). Ultimately, we now know that the use of high dose IL-2 in melanoma can produce a complete response in about 5-6% of the patients, with some of those responses being durable (lasting).  

Current Immunotherapy (also referred to as Check Point Inhibitors)

Ipilimumab (Brand name = Yervoy, slang = 'ipi') – anti-CTLA-4 monoclonal anti-body

Ipilimumab is a monoclonal anti-body that is used to restart the immune system by targeting CTLA-4, a protein receptor that actually turns the immune response OFF!!! The concept of using anti-CTLA-4 antibodies to treat cancer was developed by Dr. James Allison, for which he was awarded a Nobel Prize in 2014.  It was approved for melanoma (Stage IV or unresectable Stage III) in 2011. It was approved as an adjuvant treatment for melanoma in 2015. However, we have since learned that melanoma patients with advanced disease respond much better to the ipi/nivo combo rather than ipi as a single agent and folks in need of adjuvant therapy do much better with one of the anti-PD-1 products.  Ipi as a single agent was administered via an IV infusion every 3 weeks, for a total of 4 doses, at 3mg/kg for Stage IV patients and 10mg/kg for adjuvant therapy. Some adjuvant treatment plans continued ipi at that same dosage but every 12 weeks for up to 3 years. Melanoma patients given ipi can attain a response rate of about 15%. Responses can be durable.   Patients experience more side effects with ipi than they do with anti-PD-1 products and ipi is the bad boy of side effects in the ipi/nivo combo.  Ipi at 10mg/kg produces more side effects than ipi at 3mg/kg.  The ipi/nivolumab combo was FDA approved in (2015).  In that treatment, patients are given an infusion of ipi at 3 mg/kg after nivo at 1mg/kg is given on the same day, every 3 weeks, for 4 doses, followed by one year of nivo as a single agent. 

Anti-PD-1 (Brand names = Opdivo and Keytruda, Nivolumab and Pembrolizumab respectively.)

      

Background:  PD-1, also called programmed cell death protein 1, is a membrane protein and a T cell regulator, first discovered to be an immune checkpoint in 2000.  PD-1 is expressed on the surface of activated T cells, B cells and macrophages (white cells that can be involved in tissue repair or digestion of debris or pathogens). Compared to CTLA-4, PD-1 is keyed to specific tissues with the PD-L1 ligand, while CTLA-4 is less specific.

PD-L-1 is a ligand present on the surface of melanoma tumors (as well as some others) that can bind to infiltrating t-cells and turn them off!!

  

ANTI-PD-1 (the drugs) are monoclonal antibodies that block the switch on T cells so that PD-L1, on the surface of melanoma tumor cells, does NOT bind with them and turn them off....thereby allowing these cells to carry on and destroy melanoma tumors.

Sometimes pictures tell the story better:

    Nivolumab: (Brand name = Opdivo, slang = 'nivo') - anti-PD-1 monoclonal antibody

I wrote a little story about the development of nivo here, but basically, in 2014 Nivo was approved for the use in advanced melanoma patients only AFTER they had failed ipi and, if BRAF positive, BRAF inhibitors as well.  In November 2015 it was approved as a first line drug for unresectable or advanced melanoma BUT you had to be BRAF positive.  (A cosmically ridiculous judgement since we already had studies proving that BRAF status made little to no difference in response!!)  Finally, in 2016, based on the results of the  Checkpoint-067 study, nivo was approved for use alone or in combination with ipi, in advanced melanoma patients, no matter BRAF status.  And in 2017, it gained approval as an adjuvant treatment option.  This was seriously good news!!!  It meant even if you are Stage IV with all tumors removed (or zapped) - you can still take nivo.  Or, if you are Stage III with melanoma that went to your lymph nodes - you can take nivo!   Since then, nivo has also been approved for use in NSC lung cancer, urothelial and renal cell cancers, gastric and esophageal cancers, hepatocellular carcinoma as well as head and neck cancers.

      Pembrolizumab: (Brand name = Keytruda, slang = 'pembro') - anti-PD-1 monoclonal antibody

Pembro was similarly approved for advanced melanoma in 2014.  Since then it has been approved in various algorithms for NSCLC, head and neck squamous cell cancers, Hodgkins lymphoma, and endometrial cancers.  In 2019, it was approved for adjuvant treatment of Stage III melanoma and for Stage II adjuvant melanoma in December of 2021.

Response rate and side effects for advanced melanoma patients:

Both anti-PD-1 drugs as single agents effect about a 40% response rate in melanoma. They can work in the brain and the body.  Median time to response is about 3 months.  But, there are outliers, with documented responses, that do not occur until 6 - 9 months.  Here's a cool graph...

Here's a post with more info: Time to Response...Ipi vs Nivo and ipi 

Responses to immunotherapy have proven to be durable!!!   This post includes neat charts regarding response and durability to Pembro: Dr. Daud review from ASCO 2016   There is this from 2020:  Response after discontinuation of anti-PD-1 in melanoma patients whether due to disease progression, side effects or choice  And this from 2021:  ASCO 2021 - Outcomes of treatments on advanced disease - Reasons for HOPE!!!!!

Side effects are similar for both drugs and are those typical for immunotherapy, but less severe than those encountered with ipi.  As expected, the ipi/nivo combo has greater side effects than when nivo or pembro are used alone.  On the topic of side effects...they SHOULD be treated!!!  As quickly as possible.  At times, a break from medication and immunosuppressive drugs are required.  While oncologists not familiar with immunotherapy may fear decreased therapeutic response if steroids are used...the preponderance of the data indicates that THIS IS NOT THE CASE!!!!  Clearly, one should not take immunosuppresive drugs unless absolutely needed.  Many patients require varying doses of steroids in order to tolerate necessary, life saving melanoma treatments  and go on to do well!  Further, folks with pre-existing autoimmune disease can be managed on immunotherapy and gain a response as well.  Here are a zillion reports on all of that jazz:  What to do about immunotherapy if you need steroids or have a pre-existing autoimmune disease?

Dosing:

When Pembro is used as a single agent = is dosed at 2mg/kg with max of 200 mg IV every 3 weeks - for one year as adjuvant, end point undefined for advanced melanoma patient.  Nivo as single agent = is dosed at 240 mg IV every two weeks or 480mg IV every 4 weeks - for one year as adjuvant, endpoints vary for advanced melanoma patients. When ipi is combined with nivo, response rates in melanoma rise to 50+%, though side effects increase as well - mostly due to ipi.  For the combo, dosage is:  nivo at 1 mg/kg followed by ipi at 3 mg/kg on the same day, every 3 weeks for 4 doses, then nivo alone at 240 mg q 2 wks or 480 mg q 4 wks. endpoint varies. Many patients cannot tolerate all 4 doses of the ipi/nivo combo due to side effects.  However, outcomes can be good even if you have to stop early. Here's a report from ASCO 2016:  ASCO 2016 - Nivo plus ipi, CheckMate 069 trial....18 month OS similar even if you stop meds due to side effects!!!  Further, the ASCO 2021 data (link above) notes "Clinical benefit response (CBR) after 1 or 2 doses of I/N may be predictive of long-term survival in advanced stage melanoma. Patients who have CBR after 1 or 2 doses of I/N may achieve a similar survival benefit with fewer doses of I/N."  Finally, most folks who cannot tolerate the combo can go on to tolerate nivo alone, once their side effects are brought under control with a medication break and/or steroids.  

   Anti-PD-1 (Opdivo) plus Anti-LAG-3 (Relatlimab):

In March of 2022, Relatlimab (an anti-LAG-3 drug) was approved in combination with Nivolumab for advanced melanoma patients in the form of a new drug combo - Opdualag.  Here is a report that covers lots of pertinent data- FDA approves Relatlimab plus Nivolumab (Opdivo) for advanced melanoma patients - the down and dirty on Opdualag!!!!

TARGETED THERAPY

At this point in melanoma, the only approved targeted therapy is for patients whose tumor is positive for the BRAF V600 mutation.  About 50% of melanomas are.  However, researchers are looking at drugs that could target other points in the molecular pathway of melanoma.  This diagram shows what I mean by "pathway"...

A Melanoma Molecular Disease Model (See the link below for credit and more info)

Here's just one example from March of this year:  What tangled 'paths' we weave: Nilotinib for KIT mutated melanoma and Buparlisib for the PI3K pathway in melanoma brain mets

But....for current purposes....I am focusing on the BRAF mutation.  Here's a post I made a bit ago that really breaks down what BRAF is, what it means in melanoma, and how the drugs work:  BRAF inhibitors for melanoma: Dabrafenib, Vemurafenib, Dabrafenib/trametinib combo. Answers!!!!!

Usually when we combine drugs, we end up with increased side effects. However, in the case of BRAF targeted therapy we now know that BRAF inhibitors should ALWAYS be given with a MEK inhibitor.  Strangely enough, when the combo is given, patients experience better response rates, DECREASED side effects, and DECREASED rates of tumor work-around.  The only exception is when MEK inhibitors are used as a single agent in specially mutated patients.

DRUGS, administration, and side effects:

BRAF inhibitor (BRAFi) drugs include:  Vemurafenib (Zelboraf), Dabrafenib (Tafinlar), Sorafenib (Nexavar), and Encorafenib (Braftovi)
MEK inhibitors (MEKi) include:  Trametinib (Mekinist), Cobimetinib (Cotellic) and Binimetinib (Mektovi)

These drugs are administered orally.  So that's super cool.  Dosing depends on the particular drug.
Side effects include joint pain, rashes, extreme sun sensitivity, development of benign skin cancers, fevers and sometimes liver toxicity.

EFFECTIVENESS and tumor work-around:

For patients who are BRAF positive, BRAF inhibitors combined with a MEK inhibitor have impressive response rates, clearing tumors rapidly, and often completely, in about 70-80% of patients and are effective in the brain and body. However, those responses are not very durable, with most tumors learning to work around the inhibition in about 7-9 months. BUT!!!!  By using an "alternate dosing schedule" (one that is varied, rather than absolute with an 'every so many hours daily' dosing pattern), combining BRAFi with MEKi, as well as the development of the newer drugs that time can be stretched out a bit.  Furthermore, despite the statistics, there are some melanoma peeps whose melanoma has been successfully managed for years on BRAF/MEK combo's!!  Finally, some melanoma specialists use BRAF/MEK combo's in BRAF positive patients, to rapidly decrease the tumor burden, then switch the patient to slower acting, but more durable immunotherapy.  Picking which targeted therapy to use can be difficult.  Here are two posts that attempt to pull response rates and PFS out of the data ~

From 2018:   Well, okie dokie!!! BRAFTOVI/MEKTOVI (Seriously guys??? That's the name???!!!) Encorafenib with Binimetinib approved for melanoma.

From 2019:  BRAF/MEK combo's for melanoma analyzed ~

IMMUNOTHERAPY COMBINED WITH TARGETED THERAPY -

In 2020, the PD-L1 blocking antibody Atezolizumab (Tecentriq) combined with Cobimetinib (Cotellic) and Vemurafinib (Zelboraf) was FDA approved.  Here is a report from 2019 that links to other reports on combining targeted and immunotherapies and includes data from the early atezo/BRAFi/MEKi trials - Treating melanoma by COMBINING targeted therapy AND immunotherapy!

INTRALSIONAL (also referred to as 'intratumoral') THERAPY

Intralesional drugs include (but are not limited to):

T-VEC - also called OncoVEX, Imlygic, or Talimogene Laherparepvec - uses the herpes virus with GM-CSF and is the only intralesional currently FDA approved (2015)  However, the following (and others) have been used in clinical trials:
CAVATAK - derived from the Coxsackievirus
T-VEC - also called OncoVEX, Imlygic,  or Talimogene Laherparepvec - uses the herpes virus with GM-CSF
PV-10 - derived from Rose Bengal
HF10 - also derived from HSV
SD101 - a TLR9 agonist
IL-2 - see note above, is also being used

These drugs are injected directly into a relatively superficial melanoma tumor.  They have been found to be effective in not only eradicating the tumor into which they have been injected, but 'by-stander' lesions as well. Researchers feel that they have the most promise when they are combined with a systemic treatment like immunotherapy.  I summarized response rates, side effects, and pretty much everything else current about these drugs in these posts which include many links within them: 

From 2021 - Intralesionals for melanoma - some new reports

Out of ASCO that year - Intratumoral or Intralesional therapy for melanoma - again. Yep, AGAIN!!! ASCO 2021, here we go!

                                     -------------------------------------------
I hope this primer will continue to be a helpful jumping off point for those in need.  What has served me best in attaining effective treatment for my melanoma has been seeking out a melanoma specialist (or at least an oncologist who cares for many melanoma patients) and never being afraid to ask questions. Asking this question of my doctor may have been the most beneficial:  "What treatment would you recommend if it were YOU or your brother, sister, wife, father, mother.... in need?"

I wish you all my very best. Hang in there.  And as ever, with enduring thanks to the ratties! - love, c

P.S. If all the acronyms are driving you crazy, here's a post that defines at least some of them:  Melanoma abbreviations ~ and random thoughts on posting melanoma crap-ola....
P.S.S.  A sense of humor really does help!!  AND FINALLY - while not all inclusive, this post from 2019 includes a list of world class melanoma specialists:   Internationally renowned melanoma specialists:  - c

Strategies for treating melanoma subtypes - Acral, Mucosal, Uveal, Nodular, Lentigo

 

While melanoma, despite the huge improvements made when targeted and immunotherapies gained FDA approved in 2011 remains a very difficult cancer to treat and survive, the subtypes noted in the title make cutaneous melanoma look like a walk in the park.  This LINK takes you to reports on those subtypes that I have previously posted.  The link below takes you to a pretty thorough report addressing these particular forms of melanoma as well as a good history regarding BRAF status.  I have included much of the report below.  Words are from the authors - not me.  However, checking out the link is valuable, as it includes tables and references not reported here.

Emerging strategies to treat rare and intractable subtypes of melanoma. Gretchen and Vito. Pigment Cell Melanoma Res. Jan 2021.

Melanoma is the deadliest form of skin cancer, possessing a diverse landscape of subtypes with distinct molecular signatures and levels of aggressiveness. Although immense progress has been achieved therapeutically for patients with the most common forms of this disease, little is known of how to effectively treat patients with rarer subtypes of melanoma. These subtypes include acral lentiginous (the rarest form of cutaneous melanoma; AL), uveal, and mucosal melanomas, which display variations in distribution across (a) the world, (b) patient age-groups, and (c) anatomic sites. Unfortunately, patients with these relatively rare subtypes of melanoma typically respond worse to therapies approved for the more common, non-AL cutaneous melanoma and do not have effective alternatives, and thus consequently have worse overall survival rates. Achieving durable therapeutic responses in these high-risk melanoma subtypes represents one of the greatest challenges of the field. This review aims to collate and highlight effective preclinical and/or clinical strategies against these rare forms of melanoma.

INTRO - 

The melanoma field represents a paradigm for preclinical and clinical advancements in targeted and immune therapy modalities, with 13 new FDA-approved therapies since 2011. The catalyst for the development of targeted therapy modalities was the identification of activating NRAS mutations and BRAF mutations in 1984 and 2002... which paved the way for molecular stratification of the melanoma patient population. Approximately 45%–50% of non-acral lentiginous (AL) cutaneous melanoma patients have tumors that harbor activating BRAF mutations, with a single amino acid substitution of valine for glutamic acid at codon 600 (V600E) occurring in 90% of cases. Activating NRAS mutations at codon 12, 13, or 61 are detectable in 15%–20% of non-AL cutaneous melanoma patients and serve as an independent predictor of worse patient overall survival. Mutations of BRAF and NRAS are considered mutually exclusive; however, there are rare reports where both mutations exist in different regions of the same tumor or at different metastatic sites of the same patient. To date, it remains unclear whether the same melanoma cell can harbor both a BRAF and an NRAS mutation, or at the single-cell level, these mutations are indeed mutually exclusive.

With discoveries revealing that ~70% of non-AL cutaneous melanomas contain mutations constitutively activating the mitogen-activated protein kinase (MAPK) pathway came intense development of inhibitors capable of targeting various nodes of the mitogen-activated protein kinase (MAPK) pathway (i.e., BRAF, MEK, and ERK inhibitors) that continues to date. The first targeted therapy approved for the treatment of patients with BRAFV600E/K mutant melanoma was the small molecule inhibitor vemurafenib, an agent designed to have high specificity against the mutant V600E, V600K, V600D, and V600R forms of BRAF. Vemurafenib had response rates of ~48% in phase II and III clinical trials leading to the 2011 Food Drug and Agriculture (FDA) approval. A few years later, the combination of a BRAF inhibitor and a MEK inhibitor was observed to further increase the response rate to ~76% leading to the 2014 FDA approval of dabrafenib and trametinib. There are now three BRAF inhibitor plus MEK inhibitor combinations FDA approved for melanoma patients with BRAFV600E/K mutations (dabrafenib/trametinib, vemurafenib/cobimetinib, and encorafenib/binimetinib.

For patients with wild-type BRAF, treatment with BRAF inhibitors that specifically target V600E/K mutant BRAF may increase melanoma aggressiveness due to the paradoxical activation of wild-type BRAF and downstream MAPK pathway signaling. Preclinically, targeting downstream of BRAF with MEK inhibitors in BRAF-wild-type melanoma cells demonstrates the importance of the MAPK pathway for their survival, with significant anticancer activity. However, clinical trials testing multiple MEK inhibitors (i.e., binimetinib, trametinib) have concluded that although encouraging response rates and small increases in progression-free survival could be achieved in certain trials relative to dacarbazine, no significant increase in overall survival of patients with BRAF-wild-type melanoma was achieved with MEK inhibition. In an effort to increase MEK inhibitor efficacy, combination strategies with other agents (i.e., PI3K inhibitors, CDK4/6 inhibitors) are being clinically tested in the BRAF-wild-type (i.e., patients with or without NRAS-MT melanoma) setting after failure of immunotherapy. ERK inhibitors are also being clinically investigated to see if durable efficacy can be achieved in patients with wild-type BRAF, with reports showing the first-in-class ERK1/2 inhibitor ulixertinib has an acceptable safety profile and early evidence of clinical activity. Preclinical evidence suggests that concurrent inhibition of multiple nodes of the MAPK pathway in NRAS-mutant melanoma (i.e., MEK and ERK) may have synergistic activity on par with the BRAF inhibitor and MEK inhibitor combination in BRAF-mutant melanomas, and further studies evaluating this strategy are under way.

In parallel, large strides have been made in the development of immune checkpoint blockade strategies with the FDA approval of antibodies targeting cytotoxic T-lymphocyte antigen 4 (CTLA4, ipilimumab) in 2011 and programmed cell death 1 (PD1, pembrolizumab, nivolumab) in 2014  and the combination of ipilimumab and nivolumab in 2015. Immune checkpoint blockade describes the use of therapeutic antibodies that overcome immunosuppressive checkpoints with the goal of unchaining antitumor immune responses. CTLA4 and PD-1 are both receptors that suppress effector T-cell activity. These immunotherapy-based strategies elicit long-lasting responses in a subset of patients and represent a therapeutic strategy suitable for all genotypes of non-AL cutaneous melanoma. However, the majority of patients treated with immunotherapy progress within 5 years due to poorly understood primary resistance mechanisms, and clinicians still cannot reliably discriminate which patients will respond or not respond. Both tumor intrinsic (i.e., insufficient tumor antigenicity, tumor interferon-γ signaling, tumor stemness) and extrinsic (i.e., regulatory T cells, myeloid-derived suppressor cells) resistance mechanisms have been reported, and there are intense efforts focused on overcoming these therapeutic hurdles to further increase the efficacy of immune checkpoint blockade strategies.

The promising efficacy of these new therapeutic strategies has been demonstrated largely in non-AL cutaneous melanoma patients with either superficial spreading melanoma (SSM), nodular melanoma (NM), or lentigo maligna melanoma (LMM). SSM, NM, and LMM represent the most common forms of melanoma in Caucasians (>85% of cases). It is important to appreciate that most of the recent pivotal discoveries in melanoma were performed on SSM cell lines, short-term cultures, animal models, and tumor biopsies taken from patients with SSM largely due to their greater availability. AL melanoma represents the fourth and rarest subtype of cutaneous melanoma. In addition, mucosal melanoma and uveal melanoma are other rare subtypes of melanoma that are non-cutaneous in origin. The efficacy of immune checkpoint blockade is lower in rarer subtypes of melanoma relative to patients with non-AL cutaneous melanoma, which will be discussed later. There is also little information regarding the efficacy of combination BRAF inhibitor and MEK inhibitor therapy in these subtypes. 

Acral - 

Acral lentiginous melanoma is an uncommon yet relatively aggressive subtype of CMM that accounts for 2%–3% of all melanoma cases. AL melanoma arises on sun-protected, glabrous skin of the soles, palms, and nail beds. AL melanoma has been historically associated with worse 10-year survival rates relative to other forms of CMM (67.5% vs. 87.5%). Further, 10-year AL melanoma survival rates are highest in non-Hispanic Whites (69.4%), intermediate in Blacks (71.5%), and lowest in Hispanic Whites (57.3%) and Asian/Pacific Islanders (54.1%), as found by the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute evaluating data from 17 population-based cancer registries from 1986 to 2005. Another analysis of AL melanoma prognostic features in a cohort of German, Swiss, and Austrian patients suggests no significant difference exist relative to other subtypes of cutaneous melanoma; however, this conclusion may stem due to differential ethnicity landscapes between this patient cohort and that in the SEER study. There does not appear to be a gender bias, with a similar frequency between men and women and a comparable median age of diagnosis of 63.1 years for men and 62.2 years for women. The incidence of AL melanoma increases with age, and for reasons poorly understood, men are twice as likely to develop AL melanoma relative to women after the age of 80.

The distribution of AL melanoma varies geographically among populations throughout the world. While AL melanoma represents only ~2%–3% of all melanoma cases in Caucasian populations, AL melanoma makes up 50%–80% of all cases in non-Caucasian individuals in the United States (i.e., those of African, Latin American, and Asian descent). Furthermore, the incidence in Hispanic Whites doubles compared to non-Hispanic Whites after the aged of 70. A 2009 SEER study found the overall incidence rates of AL melanoma were similar between non-Hispanic Whites and Blacks; however, Hispanic Whites have statistically higher incidence rates relative to non-Hispanic Whites . Updated epidemiological studies should be performed to continue understanding the differential incidence trends that may exist across different ethnicities. Of note, the incidence of other subtypes of cutaneous melanoma (i.e., NM, SSM) is much lower in non-Caucasians relative to Caucasians. As this subtype of melanoma is not related to ultraviolet radiation (UV), there are different theories of the cause of AL melanoma. Some reports state that trauma and pressure in the foot (a predilected area of AL) is causal. However, the hand is also exposed to trauma but its location is less favorable. The main sites of AL melanoma metastases are the lungs, distant lymph nodes, scalp, contralateral limb, and liver.

Acral lentiginous melanomas possess a significantly lower mutational burden relative to the more common cutaneous melanoma subtypes, likely due to the sun-protected locations they arise from. BRAF mutations in are found in 1 in every 5 Al melanoma patients, leaving ~80% ineligible to receive BRAF inhibitor and combination BRAF/MEK inhibitor strategies . Therefore, new targets specific for AL melanoma are needed. 80% of AL melanomas display genetic aberrations of cyclin-dependent kinase 4/6 (CDK4/6) pathway-related genes (i.e., amplification of CDK4 and CCND1, and/or loss of CDK2NA), representing the most frequent copy number alteration detected . Additionally, activating KIT mutations are present in ~6% of cases. AL melanoma displays similar incidence of NRAS mutations as non-AL cutaneous melanoma, detectable in 15%–28% of AL melanoma patients, and NRAS mutations are an independent prognostic factor of worse overall survival.

Considerable barriers exist to treat patients with AL melanoma: (a) a contrasting genomic and genetic landscape relative to non-AL cutaneous melanomas, (b) unclear targetable drivers, and (3) sparse experimental models available for preclinical drug development. Unfortunately, FDA-approved targeted therapy strategies for melanoma are not available for the majority of AL melanoma patients (i.e., BRAF inhibitors since AL melanoma has a low frequency of BRAF mutations), and the efficacy of immune checkpoint blockade strategies is not well known in AL melanoma, with differing overall response rates (ORR) differing by country. For example, the ORR of anti-PD-1 in AL melanoma patients was found to be similar to that in non-AL cutaneous melanoma patients within the United States. In contrast, the ORR was 66.7% for SSM patients and 28.6% of AL melanoma patients in a recent Japanese study, suggesting the efficacy of immune checkpoint blockade may vary with ethnicity. The lower mutational burden observed in AL melanoma cases is thought to drive the reduced efficacy of immune checkpoint inhibitor strategies (e.g., PD-1 blockade) in patients. Although AL melanoma patients with Kit mutations can be treated with a KIT inhibitor per National Comprehensive Cancer Network (NCCN) guidelines, resistance mechanisms that reactivate downstream MAPK and PI3K pathway signaling have been suggested to blunt long-term durability. Due to the high percentage of AL melanoma tumors with CDK4/6-pathway aberrations, CDK4/6 inhibition represents one of the most promising targeted therapy strategies for AL melanomas clinically. However, durable responses are not observed in all patients due to resistance and CDK4/6 inhibitor-based combinations will likely be needed to improve the curative rate for patients with AL melanoma. Preclinical investigation to optimize targeted therapy strategies has not been extensively performed in AL melanoma models, but the rich body of literature that exists from studies in non-AL cutaneous melanoma models strongly suggests that single-agent approaches will not be durable due to the nearly universal onset of resistance. In SSM models, treatment with a MAPK pathway inhibitor plus a CDK4/6 inhibitor has shown synergistic activity in BRAF-MT and BRAF-wild-type settings; however, residual disease persists. Resistance mechanisms to CDK4/6 inhibitors and/or MEK inhibitors must be delineated to develop combination strategies that produce durable responses in AL melanoma patients.

Mucosal Melanoma - 

Mucosal melanoma (MM) is one of the rarest types of melanoma, accounting for only 1% of all cases, and has a significantly worse prognosis relative to the other subtypes. Distinct from cutaneous melanoma, MM arises from melanocytes located in mucosal membranes inside the body (i.e., genitourinary, anorectal, nasopharyngeal). The head and neck (55), vulva (18), and anus (24) are the most common observed sites; however, MM can also occur in the gut, lungs, and urinary track. It is rarely diagnosed at early stages due to difficult visual detection, which is much more tractable for cutaneous subtypes of melanoma. The overall median age of diagnosis is 70 years, with the exception of MMs arising in the mouth that manifest more frequently in younger patients. The incidence of MM has been stable for the last few years with the exception of MM in the genital tract, which is higher in females relative to males for reasons not clearly understood.

Approximately 3%–15% of MMs harbor an activating mutation in BRAF, with ~63% located on the V600 codon and 37% located on a non-V600 codon. This is in contrast to non-AL cutaneous melanomas where <10% of BRAF mutations are outside of the V600 codon, and more closely resembles the high prevalence of non-V600 mutations found in 48% of lung adenocarcinomas. A closer analysis of the most common non-V600 mutations reveals (a) a difference between the frequency of mutations on D594, G469, and K601 between non-AL cutaneous melanomas and MMs, and (b) convergence in the non-V600 mutational landscape between MM and lung cancers where mutations are often associated with genotoxic agents.

In regard to NRAS mutations, approximately 12% of MMs harbor activating mutations, which is lower relative to cutaneous melanomas where NRAS mutations occur in 15%–20% of cases. There is also a divergence in the location of NRAS mutations between MM and cutaneous melanoma, with 54% located on codon 61 in MM versus 88% in cutaneous melanoma, and 46% located on codons 12 and 13 in MM versus 12% for cutaneous melanomas. Approximately 7%–22% of MMs have v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) somatic mutations or amplifications. MMs located in the genital area appear to be driven by mutations in SF3B1 which encodes the subunit 1 of splicing factor 3b, a component of the spliceosome that processes pre-mRNA into mature transcripts. A recent study analyzing the mutational landscape of MM identified IGF2R mutations in 31.7% of MM samples relative to 6.3% of SSM cases. Interestingly, a lower frequency of UV-induced DNA damage, a lower number of mutations and a link to high tobacco exposure have also been identified in MM.

Unfortunately, MM is typically detected at relatively more advanced states due to difficulty in early detection. The main treatment for MM differs slightly on where the tumor is located; however, like any other subtype of melanoma, patients are initially treated with surgical excision. MMs arising in the head and neck are treated with complete surgical excision of the tumor when the patient is in stages III and IVA. However, this is associated with a high rate of recurrence. MMs that have arisen in the vulvovaginal or anorectal area also receive radiation in addition to surgical tumor excision. Therapeutic efficacy may be improved in select patients when treatment is personalized by tumor mutational status. Clinical trials targeting KIT with imatinib show no clear effect in unselected metastatic melanoma patient populations, but encouraging clinical benefit has been observed with KIT inhibition specifically in patients with melanomas harboring KIT mutations (not in patients whose melanoma harbor KIT amplification only). Nonetheless, disease progression ultimately occurs in the majority of cases. These data support the practice of determining KIT mutational status for MM patients to have a higher chance of receiving additional clinical benefi. Subsequent phase II clinical trials now require a KIT alteration for enrollment. For the relatively small number of MM patients whose tumors harbor BRAF mutations (relative to the ~50% in non-AL cutaneous melanoma patients), treatment with combination BRAF inhibitor and MEK inhibitor therapy is available. However, the efficacy of targeted therapy specifically in the MM patient population is not completely understood due to the low number available for analysis.

The efficacy of immune checkpoint inhibitor therapy also remains unclear in MM patients, with conflicting evidence of whether MM patients respond as well as non-AL cutaneous melanoma patients. In one multi-institutional analysis of clinical trials focusing on all the subtypes of metastatic melanoma, patients with MM had similar responses compared with non-AL cutaneous melanoma patients when treated with anti-PD-1 single-agent therapy, with a progression-free survival of 3.9 months . In another pooled analysis, MM patients treated with nivolumab as monotherapy or nivolumab in combination with ipilimumab experienced reduced clinical benefit relative to non-AL cutaneous melanoma patients. MM patients experienced 50% shorter progression-free survival (3.0 months) relative to patients with non-AL cutaneous melanoma (6.2 months) for monotherapy (nivolumab) and for nivolumab plus ipilimumab (5.9 vs. 11.7 months. Another recent study combining axitinib (small molecule receptor tyrosine kinase inhibitor) with toripalimab (anti-PD-1) found a median progression-free survival of 7.5 months in among 29 patients with chemotherapy-naïve mucosal melanoma. Although these data suggest that MM patients may not achieve as much benefit with immune checkpoint inhibitor therapy as non-AL cutaneous melanoma patients, it should be considered that in each of the pooled analyses, the number of MM cases was only 10% of patients compared to 75% from cutaneous melanoma. Also notable, another prospective study where 44 patients with unresectable MM were treated with immune checkpoint inhibitors concluded that the site of origin for MM (i.e., vaginal, anal) may not have a significant impact on the objective response rate, which was 8.2% for ipilimumab and 35% for pembrolizumab. The lower mutational burden in MM relative to non-AL cutaneous melanoma may explain the decreased efficacy of immune checkpoint blockade in MM.

Uveal Melanoma -

Uveal melanoma (UM) is the most common form of ocular melanoma, as well as the most prevalent form of non-cutaneous melanoma, accounting for 5% of all melanomas . It most commonly arises in non-Hispanic Whites relative to other races (i.e., African and Asian Americans), with a slight predominance for men (52.3%) relative to women (47.7%). The incidence of UM has remained stable over the last few decades and is diagnosed in 4–5 per million individuals in the United States each year. The median age of diagnosis is 62, and the incidence of UM increases with age. Early detection of UM provides a favorable 85% survival rate; however, this survival rate significantly decreases to 15% once UM cells have disseminated. Approximately 50% of UM patients develop metastases, and among patients with metastatic disease, 90% have liver involvement and ~70% have liver-only disease. This is a distinct metastatic pattern relative to cutaneous melanoma or mucosal melanoma.

Unlike non-AL cutaneous melanomas, UMs have a much lower mutational burden due to the sun-protected site they arise from within the ocular cavity. Activating mutations in BRAF or NRAS are not detected (extremely rare) in tumor cells of UM patients. In contrast, the main drivers for UM are activating mutations of guanine nucleotide-binding protein G (GNAQ/11), splicing factor 3B subunit 1 (SF3B1), eukaryotic translation initiation factor (EIF1AX), and inactivating mutations of the tumor suppressor BRCA-associated protein-1 (BAP1). The GNAQ/11 genes encode specific GTP binding proteins that mediate signal transduction from the inner cell surface to the MAPK pathway through activation of the protein kinase C (PKC) enzyme. GNAQ and GNA11 mutations are mutually exclusive, and thus in total are detected in 85%–94% of UM across all stages of disease. Due to their detection in benign uveal nevi, GNAQ/11 mutations are thought to be early mutational events.

BAP1 (located on the short arm of chromosome 3) loss-of-function mutations are posited to serve as a predisposing factor for diverse hereditary cancers including mesothelioma, cutaneous melanoma, renal cell carcinoma, and UM. A recent comprehensive review identified that among 174 patients harboring germline BAP1 mutations, 130 developed tumors that were either UM (31% of cases), cutaneous melanoma (13% of cases), renal cell carcinoma (10% of cases), or MM (22% of cases). In UM, loss of BAP1 returns melanoma cells to a more stem cell-like state as BAP1 is involved in melanocyte differentiation. BAP1 is frequently mutated in metastasizing uveal melanomas, which supports the growing evidence that stem-like melanoma cell states drive elements of the metastatic cascade.

There has been a recent decline in UM patients treated solely with surgery due to micrometastases that develop years before primary tumor detection. The current approach for treatment of metastatic UM is radiation; however, the survival rate is not significantly improved relative to what is possible from surgery. There have been an array of clinical studies trying to identify efficacious therapeutic strategies for patients with metastatic UM. UM patients that possess GNAQ or GNA11 mutations can be treated in clinical trials with targeted therapy approaches specific for the MAPK pathway (i.e., MEK inhibitor, ERK inhibitor) as these tumors display elevated MAPK activity. Preclinical studies have shown that treatment of UM with a combination of a MAPK pathway inhibitor and a PKC inhibitor may provide synergistic efficacy relative to what is achievable by either agent alone. Clinical trials with selumetinib, a MEK inhibitor, reported a higher progression-free survival among UM patients (15.9 vs. 7 weeks); however, no clinically meaningful increase in overall survival was observed in comparison to the chemotherapeutic temozolomide in the metastatic setting (10.8 vs. 9.4 months). Additionally, preclinical studies identified that targeting the PI3K/AKT pathway (in GNAQ and GNA11 mutant xenograft models) in combination with a MEK inhibitor may be an effective treatment strategy for patients with GNAQ or GNA11 mutations; however, clinical trials using this combination have stopped due to low response rates and high toxicity. Inhibitors against bromodomain and extraterminal (BET) proteins have had encouraging activity preclinically in UM, which could be further increased by concurrent inhibition of escape mechanisms mediated by fibroblast growth factor receptors. Similarly, targeting microenvironment-derived factors including HGF can also increase MEK inhibitor efficacy against UM cells, preclinically. For UM with BAP1 mutations, it has been shown preclinically that treatment with a histone deacetylase (HDAC) inhibitor could be beneficial. Because BAP1 mutations are associated with loss of melanocytic differentiation, treatment with HDAC inhibitors (valproic acid) are postulated to inhibit the growth of uveal melanoma in vivo by inducing morphological differentiation.

While immune checkpoint inhibitors are the standard of care for cutaneous melanoma, UM has not yet had a phase III clinical trial for immune therapy. Small studies in UM patients (10 patients) treated with pembrolizumab (anti-PD-1) after treatment with ipilimumab reported a median progression-free survival of 18 weeks; ranging from 3.14 to 49.3 weeks. Of the eight evaluable patients, four rapidly progressed, one had stable disease, two had partial responses, and one had a complete response. Although this small study resulted in comparable results seen in patients with non-AL cutaneous melanoma, other studies suggest far lower response rates to single agent anti-PD-1 and combination anti-PD-1 plus anti-CTLA-4 in UM patients. An analysis of Danish UM patients observed partial responses in 7% of patients to anti-PD-1 and 21% to concurrent anti-PD-1 plus anti-CTLA-4. Metastatic UM patients treated with ipilimumab from two additional clinical studies had a median overall survival of 9 months (in contrast to 19.9 months in non-AL cutaneous melanoma). Despite the reduced efficacy of immune checkpoint blockade in UM patients, this option may represent the most effective strategy to date.

Nodular Melanoma -

Nodular melanoma represents the second most common subtype of melanoma, responsible for 10%–15% of total melanomas in Caucasians. NM is the melanoma subtype most associated with increased thickness at clinical presentation, which is attributed to the relatively poorer prognosis of patients with NM. The median age of diagnosis for NM is 53 years, with thicker tumors more common in older patients. NM is more common in women than men for reasons poorly understood and commonly presents de novo on the head, neck, or trunk of patients.

Activating BRAF mutations are detected in patients with NM at a slightly lower frequency relative to SSM, with 43%–47% of patients possessing mutations mostly (88% of cases) in V600E. A recent study identified evidence that BRAFV600E expression may serve as a prognostic marker in primary NM associated with ulceration and reduced survival. Preclinically, it was reported that hyperactivation of the downstream MAPK effector ribosomal protein S6 kinase (RSK1) is detectable in metastatic tumor tissues derived from NM to a higher extent relative to SSM. Activating NRAS mutations are detected at a significantly elevated frequency in NM relative to SSM in 30%–33% vs. 19% of cases, respectively. Interestingly, BRAF and NRAS mutations may not be as mutually exclusive in NM relative to SSM, with the identification of both mutations in the same tumor specimens when assessed by laser capture dissection followed by direct sequencing analysis of exons 11 and 15 of the BRAF gene and exons 1 and 2 of the NRAS gene. Additional high-throughput sequencing of patient-derived samples of single nucleotide variations (SNVs) expected to impact protein coding reveals NOTCH4, RPSKA6, BCL2L12, TERT, ERBB3, ZNF560, SSPO, and SNX31 to be significantly under-mutated in NM relative to SSM.

An analysis of the most recent Surveillance, Epidemiology, and End Results (SEER) cohort and the New York University (NRU) cohort suggests that relative to patients with metastatic SSM treated with BRAF inhibitor (BRAFi) therapy, patients with metastatic NM may respond worse to BRAFi for reasons not completely understood, suggesting the potential existence of distinct clinical and biological properties between NM and SSM. The observation of activated RSK1 via constitutive phosphorylation at the Ser-380 residue may explain the poorer efficacy of BRAFi and/or BRAFi/MEKi in patients with this melanoma subtype. In contrast, no significant difference in response rates and survival was detected in NM versus SSM among a cohort of 154 patients treated with either anti-CTLA-4, anti-PD-1, or the combination of both immune checkpoint inhibitor approaches. Immune checkpoint blockade may serve an ideal first-line therapy for patients with this subtype.

Lentigo Maligna - 

Lentigo maligna (LM) is the third most common subtype of melanoma, comprising roughly 4%–15% of all melanoma cases and its incidence has dramatically increased over the past few decades across the United States, and other regions of the world. LM melanoma typically presents on chronically sun-damaged (CSD) skin of the head and neck, appearing as an irregular brown macule commonly on the head and neck in the elderly. In contrast to the mean age of diagnosis of SSM between 40 and 60 years, the mean age of diagnosis for LM melanoma is 66–72 years. Credit is given to Sir John Hutchinson for the earliest description of LM melanoma in 1890. LM melanoma was initially referred to as “Hutchinson’s melanocytic freckle” due to the prevailing thought that it was benign, non-infectious lesion owing to its slow growing nature. Critical work by Ackerman and Silvers in the late 1970s–1980s finally led to wide acceptance of LM melanoma as a malignant disease worthy of clinical attention and intervention. Chronic ultraviolet radiation is the major risk factor for the development of LM melanoma, which differs from NM and SSM that are associated with intense intermittent ultraviolet radiation exposure. LM melanomas arise most frequently on the face and other sites of chronic sun damage which also differs from NM and SSM that arise most commonly on the trunk in men and legs in women. LM melanoma is thought to occur in older patients due to the increased lifetime sun and ultraviolet radiation exposure.

Lentigo maligna melanomas have a relatively high mutational burden compared to other melanoma subtypes due to chronic ultraviolet exposure. The frequency of activating BRAF mutations in LM is unclear, with reports finding 16.7%–53.4% of LM patients harboring BRAF mutations. The large variation may, in part, be attributed to the regional differences among tested patient tissue cohorts. In a Greek cohort, 16.7% of LM melanoma cases expressed BRAF mutations and 50% of LM cases in a Japanese cohort expressed BRAF mutations. When BRAF mutations are present, the V600K substitution is frequently observed (~77%) relative to the V600E (~23%) as observed in SSM, in this small set of 13 LM patient tumor samples. This finding is consistent with V600K mutations arising on chronically sun-damaged skin. Activating NRAS mutations have been reported to occur in ~8.1%–16% of LM cases .

The treatment of choice for patients with localized LM melanoma consists of surgical excision as first line of therapy, followed by radiation therapy with fractionated superficial radiotherapy, or topical imiquimod cream as an alternative to surgery. Once LM melanoma metastasizes to visceral organs, the five-year survival is similar to SSM. Interestingly, the efficacy of immune checkpoint blockade may be significantly higher in patients with LM melanoma relative to the other subtypes discussed. A study investigating the overall response rate (ORR) of anti-PD-1/PD-L1 in different subtypes of melanoma found patients with melanoma on CSD skin (including LM melanoma, desmoplastic melanoma, and subtype not-specified cases) exhibited an overall response rate of 70%, which fits the theory that cancer cells with high mutational burdens may be more sensitive to immune checkpoint blockade due to the increased presence of immune-stimulatory neoepitopes. Additional investigations on the efficacy of targeted and immune-based therapy are needed specifically for patients with LM melanoma to ensure the optimal treatment(s) is identified for this cohort and further improved through preclinical experimentation and clinical trials.

To date, this is the most comprehensive review of the data and treatments best suited for these melanoma subtypes that I have found.  So hoping that understanding and effective treatment options increase for these patients very soon.  -  c

Advanced Melanoma - A smattering of 2020 literature for Stage IV peeps

Unfortunately, though some promising trials are underway, no major breakthroughs have occurred in melanoma research of late.  Still, there are studies and data that are meaningful.  Here is a collection of reports that may be valuable to Stage IV melanoma peeps.  (My comments in red.) -

Overall Survival Improved for Contemporary Patients with Melanoma: A 2004-2015 National Cancer Database Analysis.  Farrow, Turner, Salama, Beasley.  Oncol Ther. 2020 Dec.

Introduction: Since 2011, encouraging clinical trial results have led to approval of multiple new therapies for advanced melanoma, but the impact of these therapies outside of trial populations is largely unknown. This study examines use of novel therapies and survival in contemporary patients with melanoma.

Methods: Stage I-IV melanoma patients were identified in the 2004-2015 National Cancer Database and grouped into historic (2004-2010) and contemporary (2011-2015) cohorts. Overall survival (OS) was compared using Kaplan-Meier and Cox proportional hazard modeling adjusting for patient, tumor, and facility characteristics.

Results: Of 268,668 patients, 136,828 were classified as historic and 131,840 as contemporary. Among all stages, immunotherapy utilization was significantly higher among contemporary patients. Adjusted OS was improved in the contemporary cohort. There was no difference in OS among stage I/II patients between groups, while OS was significantly improved for contemporary stage III/IV patients. Among stage III/IV patients who received immunotherapy, OS was improved for the contemporary cohort.

Conclusions: Adjusted overall survival for contemporary melanoma patients is improved. This effect is driven by improvements for those with advanced stage disease, particularly those that received immunotherapy and BRAF/MEK targeted therapies.

Confirmation of what we already know - targeted therapy (BRAF/MEK combo's) for BRAF positive melanoma patients and immunotherapy - have made a world of difference for melanoma peeps.  

Systemic Therapy for Melanoma: ASCO Guideline.  Seth, …Kirkwood, Kudchadkar…Weber, Agarwala, Ascierto, …, Faries… Robert,…Sondak, et al.  J Clin Oncol, 2020 Nov 20.

Purpose: To provide guidance to clinicians regarding the use of systemic therapy for melanoma.

Methods: ASCO convened an Expert Panel and conducted a systematic review of the literature.

Results: A systematic review, one meta-analysis, and 34 additional randomized trials were identified. The published studies included a wide range of systemic therapies in cutaneous and noncutaneous melanoma.

Recommendations: In the adjuvant setting, nivolumab or pembrolizumab should be offered to patients with resected stage IIIA/B/C/D BRAF wild-type cutaneous melanoma, while either of those two agents or the combination of dabrafenib and trametinib should be offered in BRAF-mutant disease. No recommendation could be made for or against the use of neoadjuvant therapy in cutaneous melanoma. In the unresectable/metastatic setting, ipilimumab plus nivolumab, nivolumab alone, or pembrolizumab alone should be offered to patients with BRAF wild-type cutaneous melanoma, while those three regimens or combination BRAF/MEK inhibitor therapy with dabrafenib/trametinib, encorafenib/binimetinib, or vemurafenib/cobimetinib should be offered in BRAF-mutant disease. Patients with mucosal melanoma may be offered the same therapies recommended for cutaneous melanoma. No recommendation could be made for or against specific therapy for uveal melanoma. 

YEP!

Five-Year Outcomes With Nivolumab in Patients With Wild-Type BRAF Advanced Melanoma.  Robert, Long, Brady, et al.  J Clin oncol.  2020 Nov.

Purpose: The CheckMate 066 trial investigated nivolumab monotherapy as first-line treatment for patients with previously untreated BRAF wild-type advanced melanoma. Five-year results are presented herein.

Patients and methods: In this multicenter, double-blind, phase III study, 418 patients with previously untreated, unresectable, stage III/IV, wild-type BRAF melanoma were randomly assigned 1:1 to receive nivolumab 3 mg/kg every 2 weeks or dacarbazine 1,000 mg/m2 every 3 weeks. The primary end point was overall survival (OS), and secondary end points included progression-free survival (PFS), objective response rate (ORR), and safety.

Results: Patients were followed for a minimum of 60 months from the last patient randomly assigned (median follow-up, 32.0 months for nivolumab and 10.9 months for dacarbazine). Five-year OS rates were 39% with nivolumab and 17% with dacarbazine; PFS rates were 28% and 3%, respectively. Five-year OS was 38% in patients randomly assigned to dacarbazine who had subsequent therapy, including nivolumab (n = 37). ORR was 42% with nivolumab and 14% with dacarbazine; among patients alive at 5 years, ORR was 81% and 39%, respectively. Of 42 patients treated with nivolumab who had a complete response (20%), 88% (37 of 42) were alive as of the 5-year analysis. Among 75 nivolumab-treated patients alive and evaluable at the 5-year analysis, 83% had not received subsequent therapy; 23% were still on study treatment, and 60% were treatment free. Safety analyses were similar to the 3-year report.

Conclusion: Results from this 5-year analysis confirm the significant benefit of nivolumab over dacarbazine for all end points and add to the growing body of evidence supporting long-term survival with nivolumab mono-therapy. Survival is strongly associated with achieving a durable response, which can be maintained after treatment discontinuation, even without subsequent systemic therapies.

So over comparing any melanoma treatment with dacarbazine.  At the onset of this study, I suppose it was okay - but hopefully we are well past that now!!!  At any rate - important points are just relative to nivo only treatment and survival.  Overall response rate was 42%.  Of patients alive at five years ORR was 81%.  Of the patients on nivo with a complete response, 88% were alive at 5 years.  Of nivo treated patients alive at 5 years - 83% had needed no additional treatment, 23% were still on treatment, and 60% were treatment free.

Safety and efficacy of combination nivolumab plus ipilimumab in patients with advanced melanoma: results from a North American expanded access program (CheckMate 218).  Hodi, Chapman, Sznol, et al.  Melanoma Res.  2020 Nov.

CheckMate 218, a North American expanded access program (EAP), investigated nivolumab plus ipilimumab in patients with advanced melanoma. Safety and efficacy, including 2-year survival in clinically relevant patient subgroups, are reported. Eligible patients were aged greater than/equal to18 years with unresectable stage III/IV melanoma, an Eastern Cooperative Oncology Group performance status of 0/1, and no prior checkpoint inhibitors. Patients received nivolumab 1 mg/kg plus ipilimumab 3 mg/kg every 3 weeks for 4 cycles (induction) followed by nivolumab 3 mg/kg every 2 weeks (maintenance) until progression or unacceptable toxicity or a maximum of 48 weeks. Safety and overall survival (OS) data were collected. This EAP included 754 treated patients from the USA (n = 580) and Canada (n = 174). Median follow-up time was 17.8 months. All-grade and grade 3-4 treatment-related adverse events were reported in 96% and 53% of patients and led to treatment discontinuation in 36% and 26% of patients, respectively. OS rates at 12 and 24 months were 82%  and 70%, respectively. Twenty-four-month OS rates were 63% in patients aged ≥75 years, 56% in patients with elevated lactate dehydrogenase levels, 73% in patients with BRAF wild-type tumors, 70% in patients with BRAF mutant tumors, and 56% in patients with mucosal melanoma. In this EAP, nivolumab plus ipilimumab demonstrated high survival rates and safety outcomes consistent with those from randomized clinical trials, further supporting the use of this combination for advanced melanoma across multiple subgroups.

Again - ipi/nivo with better survival than nivo alone, though with a more significant side effect profile.

PD-1 inhibitors might limit the development of brain metastases in patients with advanced melanoma.  Marcaillous, Linder, Chaltiel, et al.  Melanoma Res. 2020 Dec.

Brain metastases are a common and severe complication potentially leading to death in patients with metastatic melanoma. Immunotherapy and targeted therapy have significantly improved progression-free survival (PFS) and overall survival (OS) in patients with advanced melanoma. Few studies focus on patients with central nervous system (CNS) metastases, and these patients are often excluded and have a poor prognosis. It has been suggested that immunotherapy could reduce the incidence of brain metastases. We tested this hypothesis in a retrospective bicentric study. We performed a retrospective, bicentric descriptive analysis on a cohort of 293 patients treated for metastatic melanoma between May 2014 and October 2017. Patients with brain metastasis at diagnosis were excluded from the analysis. Patients were separated into two groups according to the first line of treatment: immunotherapy [immune checkpoint inhibitor (ICI)] vs other and anti-PD-1 vs other. The primary endpoint was the cumulative incidence of brain metastases, and secondary endpoints were OS and PFS. At 12 months, the cumulative incidence of brain metastases was 13.78% in the ICI group and 27.26% in the other group. The cumulative incidence was 9.49% in the anti-PD-1 group vs 30.11% in the other group . In multivariable analysis, anti-PD-1 reduced the risk of brain metastases by almost 70%. The use of ICI (anti-PD-1/PD-L1) in advanced melanomas without initial brain metastasis shows a protective effect and prevents their occurrence.

Yep.  Been yelling it for over 10 years!!!  Immunotherapy works in the brain.  Folks treated with anti-PD-1 had an incidence of brain met development of 9.49% vs 30.11% in patients not treated with anti-PD-1.  Analysis found that anti-PD-1 reduced the risk of brain mets by almost 70%.

PD-L1 blockade in combination with inhibition of MAPK oncogenic signaling in patients with advanced melanoma. Ribas, Algazi, Ascierto, et al.  Nat Commun.  2020 Dec.

Combining PD-L1 blockade with inhibition of oncogenic mitogen-activated protein kinase (MAPK) signaling may result in long-lasting responses in patients with advanced melanoma. This phase 1, open-label, dose-escalation and -expansion study (NCT02027961) investigated safety, tolerability and preliminary efficacy of durvalumab (anti-PD-L1) combined with dabrafenib (BRAF inhibitor) and trametinib (MEK inhibitor) for patients with BRAF-mutated melanoma (cohort A, n = 26), or durvalumab and trametinib given concomitantly (cohort B, n = 20) or sequentially (cohort C, n = 22) for patients with BRAF-wild type melanoma. Adverse events and treatment discontinuation rates were more common than previously reported for these agents given as monotherapy. Objective responses were observed in 69.2% (cohort A), 20.0% (cohort B) and 31.8% (cohort C) of patients, with evidence of improved tumor immune infiltration and durable responses in a subset of patients with available biopsy samples. In conclusion, combined MAPK inhibition and anti-PD-L1 therapy may provide treatment options for patients with advanced melanoma.

In this trial of either Durvalumab (anti-PD-L1) combined with dabrafenib/trametinib or just with trametinib or given sequentially - patients given the combination of the three drugs had a 69.2% response rate, of the 2 a response rate of 20% and in the sequential group (not clear, but I suspect that they got the three drugs) a response rate of 31.8%.  For comparison here is a report on atezo and pembro when combined with a BRAF/MEK therapy from 2019 that includes links to other reports of results when immunotherapy was combined with targeted therapy - Treating melanoma by COMBINING targeted therapy AND immunotherapy!!  When atezo and pembro were combined with a BRAF/MEK combo - responses rates were 70+%.  Of course, this treatment option is only available to about half of us as patients need to be BRAF positive.

Chemotherapy combined with antiangiogenic drugs as salvage therapy in advanced melanoma patients progressing on PD-1 immunotherapy.  Wang, Weiran, Zhihong, et al.  Transl Oncol. 2020 Nov.

Background: This study aimed to evaluate the effect of salvage therapy with nab-paclitaxel (nab-p) or temozolomide (TMZ) combined with antiangiogenic drugs in programmed death 1 (PD-1) inhibitor-resistant patients with unresectable metastatic melanoma.

Methods: We conducted a retrospective review of 69 metastatic melanoma patients who received nab-p or TMZ combined with antiangiogenic drugs after developing PD-1 inhibitor resistance and were treated at the Beijing Cancer Hospital between 2016 and 2019. The disease control rate (c-DCR) and progression-free survival (c-PFS) of salvage CA (chemotherapy combined with antiangiogenic drugs) regimens were investigated. Univariate and multivariate analyses were performed to evaluate the clinical pathological factors affecting the outcomes. Then, a nomogram was formulated to predict the probability of 3-month and 6-month c-PFS based on the multivariate analysis results.

Results: The c-DCR was 63.8%, and the median c-PFS was 3.0 months. In the univariate analysis, factors associated with the c-DCR were included the melanoma subtype, baseline platelet-to-lymphocyte ratio (PLR) and best response status to PD-1 inhibitors. Factors influencing c-PFS included age, baseline lactic dehydrogenase, PLR, neutrophil-to-lymphocyte ratio (NLR), PFS duration of anti-PD-1 therapy (p-PFS), and the best response and progression pattern of PD-1 inhibitors. In the multivariate analysis, age <65 years, heterogeneous progression pattern and baseline PLR<200 were significantly associated with improved c-PFS. The concordance index (C-index) of the nomogram was equal to 0.65.

Conclusions: CA regimens demonstrated promising effects in PD-1 inhibitor-resistant patients. The nomogram could be a valuable predictive module for salvage therapy choice in PD-1 inhibitor-resistant patients.

So these peeps created a fancy scale to determine whether a chemo cocktail would provide 3 vs 6 months of progression free survival in unresectable Stage IV melanoma folks who had become unresponsive to anti-PD-1.  Sad thing to face.  But, if this formula works, perhaps it can provide patients with knowledge that may inform their decision to accept or decline such therapy.

So there you have it.  Final 2020 reports in review for advanced melanoma patients - my take, anyway.  Over the coming days, I will plow through some other 2020 research on other topics pertinent to melanoma.  Stay safe.  Wear a mask.  Get a COVID vaccine when you can.  - c

Encorafenib/Binimetinib ~ BRAF/MEK inhibitor combo in patients with V600E/K mutant tumors

I've provided reports on this BRAF/MEK inhibitor combo before.  Here's a link to some of the posts:  Encorafenib/Binimetinib  Here's a link to reports on the COLUMBUS study in particular:  COLUMBUS

For this study, inclusion criteria on the Clinicaltrial.gov website notes:  "Written documentation of BRAF V600E mutation, or any other BRAF V600 mutation"

A phase 1b/2 study of the BRAF inhibitor encorafenib plus the MEK inhibitor binimetinib in patients with BRAF V600E/K-mutant solid tumors.  Sullivan, Weber, Patel, et al.  Clin Cancer Res. 2020 Jul 15.

This open-label, dose-finding phase 1b/2 study reports the safety and activity of the first combination use with BRAF inhibitor (BRAFi) encorafenib plus MEK inhibitor (MEKi) binimetinib in patients with BRAF V600E-mutant solid tumors. (NCT01543698). 

In phase 1, the recommended phase 2 doses (RP2D) were established (primary objective). In phase 2, the clinical activity of the combination at the RP2D was assessed (primary objective) in patients with BRAF-mutant metastatic colorectal cancer (mCRC), BRAFi-treated BRAF-mutant melanoma, and BRAFi-naïve BRAF-mutant melanoma. Results 126 patients with BRAF mutant solid tumors were enrolled (phase 1: 47 patients; phase 2: 79 patients). The RP2D was encorafenib 450 mg QD plus binimetinib 45 mg BID and pharmacokinetic (PK) data suggest that drug-exposures of each agent were similar in combination compared with single-agent studies. In the phase 2 cohorts, confirmed responses were seen in 2 of 11 (18%) evaluable mCRC patients, 11 of 26 (42%) evaluable BRAFi-pretreated melanoma patients, and 28 of 42 (67%) BRAFi-naïve melanoma patients. The most common grade 3/4 adverse event in phase 2 was increased alanine aminotransferase. 

The combination of encorafenib (450 mg) plus binimetinib (45 mg) showed acceptable tolerability and encouraging activity in patients with BRAF V600-mutant tumors, which led to the dose selection for the melanoma COLUMBUS study. The safety profile of the combination was consistent with other approved BRAFi plus MEKi regimens, with several differences, including lower rates of dose-limiting pyrexia, arthralgia, and photosensitivity.  

For what it's worth.  - c

Melanoma treatment guidelines from Melanoma Big Dogs

As much as we've learned about melanoma, there remains much we do not know.  Yet, even with the limited available treatments, the stage and indications for use, what to do about side effects, what to do next, remains confusing for patients and oncologists alike.  To that end, I put together this primer a couple of years ago:  Melanoma Intel: A primer for current standard of care and treatment options  (Unfortunately, to date, it has required no up-dates other than the dosing schedule for nivo!)

There is also this post regarding adjuvant treatment, including data from a presentation made by Jeff Weber, MD (Melanoma Big Dog extraordinaire!): ADJUVANT therapy for melanoma!!!!!!!!!!!!!! State of the science....

And finally, also with the help of Weber's presentation, what may be coming in the way of immunotherapy and other treatments:  The future of immunotherapy and cancer - per Weber

 You can find more articles on most any particular treatment by entering the word in the search bubble to the top left if you are interested.  Now, as we head into ASCO 2020, Melanoma Big Dogs have put together guidelines for the use of systemic therapies in melanoma ~

Systemic Therapy for Melanoma: ASCO Guideline.  Seth, Messersmith ... Weber ... Agarwala, Ascierto ... Faries ... Sondak, et al.  J Clin Oncol. 2020 Mar 31.  To provide guidance to clinicians regarding the use of systemic therapy for melanoma, ASCO convened an Expert Panel and conducted a systematic review of the literature. A systematic review, one meta-analysis, and 34 additional randomized trials were identified. The published studies included a wide range of systemic therapies in cutaneous and noncutaneous melanoma. In the adjuvant setting, nivolumab or pembrolizumab should be offered to patients with resected stage IIIA/B/C/D BRAF wild-type cutaneous melanoma, while either of those two agents or the combination of dabrafenib and trametinib should be offered in BRAF-mutant disease. No recommendation could be made for or against the use of neoadjuvant therapy in cutaneous melanoma. In the unresectable/metastatic setting, ipilimumab plus nivolumab, nivolumab alone, or pembrolizumab alone should be offered to patients with BRAF wild-type cutaneous melanoma, while those three regimens or combination BRAF/MEK inhibitor therapy with dabrafenib/trametinib, encorafenib/binimetinib, or vemurafenib/cobimetinib should be offered in BRAF-mutant disease. Patients with mucosal melanoma may be offered the same therapies recommended for cutaneous melanoma. No recommendation could be made for or against specific therapy for uveal melanoma. Additional information is available at www.asco.org/melanoma-guidelines.

Click on the link included to search for specifics from the guidelines.  Hang tough peeps.  We're getting there! - c