MULTIPLE PRIMARY MELANOMAS

Background: The diagnosis of primary melanoma increases the risk of ad ditional primary melanomas. Objective: We characterize the subgroup of patients with multiple melanomas. Methods: We reviewed the melanoma d atabase. Results: Sixty patients with multiple primary melanomas were identified. Twelve (20%) experienced melanomas in the same regional lo cation, 43 (72%) in different locations,and 5 (8%) in both the same an d different locations (> 2 melanomas). Eighteen (30%) were diagnosed c oncurrently with multiple melanomas, 38 (63%) subsequently, and 4 (7%) concurrently and subsequently (>2 melanomas). Forty-two percent of su bsequent melanomas occurred within 3 years of the initial lesion diagn osis, 9 (17%) between 3 and 7 years, and 22 (42%) after more than 7 ye ars. Subsequent melanomas were thinner in 70% of cases (P=.05), The me an age at first melanoma diagnosis was 38 and 59 years, respectively, for those with and without dysplastic nevi (P<.001). Conclusion: In pa tients with multiple melanomas, subsequent melanomas often occur in di fferent regional locations several years after diagnosis of the initia l lesion.