Our microbiome has been getting lots of attention and legit research in regard to health generally, as well as cancer and response to cancer therapies (immunotherapy specifically) recently. Here's a link to lots of reports: Cooties!
And given that data and the importance of the right cooties being present in our gut, it makes sense that antibiotics would certainly throw a wrench in that balance. Here's a link to some related posts: Antibiotics, gut microbes, and decreased response to immunotherapy It is interesting to note that years ago, doxycycline was found to be one of the things that killed melanoma: Doxycycline kills melanoma - at least in a petri dish
Now, there's this:
Association of Prior Antibiotic Treatment With Survival and Response to Immune Checkpoint Inhibitor Therapy in Patients With Cancer. Pinato, Howlett, Ottaviani, et al. JAMA Oncol. 2019 Sep 12.
Gut dysbiosis impairs response to immune checkpoint inhibitors (ICIs) and can be caused by broad-spectrum antibiotic (ATB) therapy. To evaluate whether there is an association between ATB therapy administered concurrently (cATB) or prior (pATB) to ICI therapy and overall survival (OS) and treatment response to ICI therapy in patients with cancer treated with ICIs in routine clinical practice.
This prospective, multicenter, cohort study conducted at 2 tertiary academic referral centers recruited 196 patients with cancer who received ICI therapy between January 1, 2015, and April 1, 2018, in routine clinical practice rather than clinical trials.
Overall survival calculated from the time of ICI therapy commencement and radiologic response to ICI treatment defined using the Response Evaluation Criteria in Solid Tumors, with disease refractory to ICI therapy defined as progressive disease 6 to 8 weeks after the first ICI dose without evidence of pseudoprogression.
Among 196 patients (137 men and 59 women; median [range] age, 68 [27-93] years) with non-small cell lung cancer (n = 119), melanoma (n = 38), and other tumor types (n = 39), pATB therapy, but not cATB therapy, was associated with worse OS (2 vs 26 months for pATB therapy vs no pATB therapy, respectively) and a higher likelihood of primary disease refractory to ICI therapy (21 of 26 [81%] vs 66 of 151 [44%]). Overall survival in patients with non-small cell lung cancer (2.5 vs 26 months), melanoma (3.9 vs 14 months), and other tumor types was consistently worse in those who received pATBs vs those who did not. Multivariate analyses confirmed that pATB therapy and response to ICI therapy were associated with OS independent of tumor site, disease burden, and performance status.
Despite being limited by sample size, geographic origin, and the lack of correlative analyses on patients' gut microbiota, this study suggests that [prior] ATB therapy but not [concurrent] ATB therapy is associated with a worse treatment response and OS in unselected patients treated with ICIs in routine clinical practice. Mechanistic studies are urgently required to investigate ATB-mediated alterations of gut microbiota as a determinant of poorer outcome following ICI treatment.
Overall survival calculated from the time of ICI therapy commencement and radiologic response to ICI treatment defined using the Response Evaluation Criteria in Solid Tumors, with disease refractory to ICI therapy defined as progressive disease 6 to 8 weeks after the first ICI dose without evidence of pseudoprogression.
Among 196 patients (137 men and 59 women; median [range] age, 68 [27-93] years) with non-small cell lung cancer (n = 119), melanoma (n = 38), and other tumor types (n = 39), pATB therapy, but not cATB therapy, was associated with worse OS (2 vs 26 months for pATB therapy vs no pATB therapy, respectively) and a higher likelihood of primary disease refractory to ICI therapy (21 of 26 [81%] vs 66 of 151 [44%]). Overall survival in patients with non-small cell lung cancer (2.5 vs 26 months), melanoma (3.9 vs 14 months), and other tumor types was consistently worse in those who received pATBs vs those who did not. Multivariate analyses confirmed that pATB therapy and response to ICI therapy were associated with OS independent of tumor site, disease burden, and performance status.
Despite being limited by sample size, geographic origin, and the lack of correlative analyses on patients' gut microbiota, this study suggests that [prior] ATB therapy but not [concurrent] ATB therapy is associated with a worse treatment response and OS in unselected patients treated with ICIs in routine clinical practice. Mechanistic studies are urgently required to investigate ATB-mediated alterations of gut microbiota as a determinant of poorer outcome following ICI treatment.
Then there's this:
Can diet help cancer treatment? Study in mice offers clues
Which discusses an article published in July and notes: "The study, published Thursday in the journal Nature, found restricting intake of an amino acid found in red meat and eggs significantly enhanced cancer treatment in mice, slowing tumour growth."
So, eat those veggies and take antibiotics only when you really need them!!!! (Not that either of those recommendations are news!) For what it's worth! - c
