Sunbelt Melanoma Trial Final Results: No survival benefit for interferon or complete lymph node dissection in patients with a single positive SLN!

Final Results of the Sunbelt Melanoma Trial: A Multi-Institutional Prospective Randomized Phase III Study Evaluating the Role of Adjuvant High-Dose Interferon Alfa-2b and Completion Lymph Node Dissection for Patients Staged by Sentinel Lymph Node Biopsy.  McMasters, Egger, Edwards, et al.  J Clin Oncol.  2016 Feb 8.

“The Sunbelt Melanoma Trial is a prospective randomized trial evaluating the role of high-dose interferon alfa-2b therapy (HDI) or completion lymph node dissection (CLND) for patients with melanoma staged by sentinel lymph node (SLN) biopsy.

Patients were eligible if they were age 18 to 70 years with primary cutaneous melanoma ≥ 1.0 mm Breslow thickness and underwent SLN biopsy. In Protocol A, patients with a single tumor-positive lymph node after SLN biopsy underwent CLND and were randomly assigned to observation versus HDI. In Protocol B, patients with tumor-negative SLN by standard histopathology and immunohistochemistry underwent molecular staging by reverse transcriptase polymerase chain reaction (RT-PCR). Patients positive by RT-PCR were randomly assigned to observation versus CLND versus CLND+HDI. Primary end points were disease-free survival (DFS) and overall survival (OS).

In the Protocol A intention-to-treat analysis, there were no significant differences in DFS  or OS  for patients randomly assigned to HDI versus observation. In the Protocol B intention-to-treat analysis, there were no significant differences in overall DFS  or OS  across the three randomized treatment arms. Similarly, efficacy analysis (excluding patients who did not receive the assigned treatment) did not demonstrate significant differences in DFS or OS in Protocol A or Protocol B. Median follow-up time was 71 months.

No survival benefit for adjuvant HDI in patients with a single positive SLN was found. Among patients with tumor-negative SLN by conventional pathology but with melanoma detected in the SLN by RT-PCR, there was no OS benefit for CLND or CLND+HDI.”

Interesting.  Not really news in the case of interferon!  Can we finally be done with that "treatment" already???!!!!  As far as the complete lymph node dissection, I guess there remains one (at least) question...and that is....What about folks with obvious tumor in their sentinel lymph node?  This study reports that in these patients with sentinel nodes that were "negative by conventional pathology, but WITH melanoma detected via RT-PCR" testing, there was no overall survival benefit to the complete lymph node dissection.  Hmmm.... This study result does stand in contrast to data showing benefit from CLND in the 2,000 patients randomly studied by Balch and Faries in their 1994-2014 study where patients were observed OR treated with lymphadenectomy if a positive node was found.  On a personal note:  My initial primary lesion was only 0.61mm thick with no ulceration.  However, a sentinel node was positive for micrometastasis. I did elect to have a complete lymph node dissection of the area but declined interferon.  Still, I developed a second thin primary in another location 4 years later (removed, negative SLN, CLND), but advanced to Stage IV with brain and lung mets 3 years after that.  Still more we have yet to figure out...but we've come a long way baby!!!  Thanks, ratties! - c