Uveal Melanoma in BAP1 Tumor Predisposition Syndrome: Estimation of Risk

Abstract Purpose To estimate point prevalence of uveal melanoma in the patients with germline BAP1 pathogenic variant. Design Cohort study with risk assessment using Bayesian analysis. Methods The point prevalence estimate was obtained by Bayes' rule of reverse conditional probabilities. The probability of uveal melanoma given that BAP1 mutation exists was derived from the prevalence of uveal melanoma, prevalence of germline BAP1 pathogenic variants, and the probability of germline BAP1 pathogenic variant given that uveal melanoma is present. Confidence intervals for each variable was calculated as the mean of Bernoulli random variables and for the risk estimate was calculated by the delta method. The age at diagnosis and the gender of the uveal melanoma patients with BAP1 germline pathogenic variants obtained from previous publications or from authors unpublished cohort was compared with those in the SEER database. Results The point prevalence of uveal melanoma in patients with the germline BAP1pathogenic variants in the United States population was estimated to be 2.8% (95% CI, 0.88% – 4.81%). In the SEER database, the median age at diagnosis of uveal melanomas was 63 (range 3-99 years) with a Male-to-Female ratio of 1.01:1. In comparison, uveal melanoma cases with BAP1 germline pathogenic variants from the United States population (n = 27) had median age at diagnosis of 50.5 (range 16-71) years. Conclusions Quantification of the risk of developing uveal melanoma can enhance counselling regarding surveillance in patients with germline BAP1 pathogenic variant.