Abstract 3419: Sex, mutations, and mortality in early stage melanoma

Abstract

Abstract Our goal is to investigate the relationship between sex, tumor mutation burden (TMB) and survival in untreated primary melanoma tumors, using data collected in an ongoing large P01 study on the Integration of Clinical and Molecular Biomarkers for Melanoma Survival (InterMEL). Here we present preliminary findings on sex, survival, and somatic TMB from 60 Stage II and Stage III primary melanoma tumors, none of which have received immunotherapy using the MSK IMPACT™ next generation sequencing assay. Our preliminary analysis includes 30 patients who died within 5 years (median survival of 31 months) and 30 patients who lived for more than 5 years since diagnosis (median follow-up of 86 months). We found the expected relationship between TMB and better survival in a univariate Cox regression analysis (HR=0.43, 95% CI=0.19 to 0.97, P=0.04), but no evidence of association between TMB and sex (Wilcoxon rank-sum test P=0.7) or any relationship between sex and survival (logrank test P=0.42). Our study is the first to investigate the relationship between sex, tumor mutational burden, and mortality in an early stage primary cohort that has not received immunotherapy. In our small sample, we observed the expected protective effect of TMB on survival, but no evidence of gender differences in TMB or survival. This is surprising given the robust, consistent, and well-documented female survival advantage (Roh et al., 2015; de Vries et al., 2008), and merits further investigation. Our results are an important first step to increasing our understanding of the relationship between mutational burden, survival, and biological sex. References Roh, M.R., Eliades, P., Gupta, S., Grant-Kels, J.M., and Tsao, H. (2015). Cutaneous melanoma in women. Int. J. Womens Dermatol. 1, 21–25. de Vries, E., Nijsten, T.E.C., Visser, O., Bastiaannet, E., van Hattem, S., Janssen-Heijnen, M.L., and Coebergh, J.-W.W. (2008). Superior survival of females among 10 538 Dutch melanoma patients is independent of Breslow thickness, histologic type and tumor site. Ann. Oncol. 19, 583–589. Citation Format: Matthew R. Schwartz, Li Luo, Marianne Berwick. Sex, mutations, and mortality in early stage melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3419.