Melanoma in a cohort of organ transplant recipients: Experience from a dedicated transplant dermatology clinic in Victoria, Australia

Background There is limited information on the profile of melanomas diagnosed in a specialist transplant dermatology clinic. Objective To describe the incidence and characteristics of incident primary melanomas in a cohort of organ transplant recipients (OTRs) attending a specialized transplant dermatology clinic and determine the number of pigmented lesions needed to excise for every melanoma diagnosed. Methods A retrospective study of 327 OTRs monitored by an Australian clinic during a 10-year period. Results There were 11 incident melanomas diagnosed during a total follow-up of 1280 patient-years. The mean interval between the first transplant and diagnosis was 5.5 years. Only 2 melanomas were >1 mm in Breslow thickness. Seven melanomas (64%) arose de novo. A contiguous nevus was present in 4 cases. Metastatic disease did not develop in the melanoma patients during the follow-up period, and all remain alive. The needed to excise for every melanoma diagnosed ratio was 16:1. Limitations The crude incidence rates were age standardized, unlike the comparison rates of melanoma in the general population, and the cohort was small. Conclusion Most melanomas diagnosed in OTR patients attending a specialized transplant dermatology service were detected early. Our data suggest early detection may reduce the proportion of OTRs presenting with thick melanomas, thus improving prognosis and patient outcomes. A needed to excise for every melanoma diagnosed ratio of 16:1 is not unreasonable for this cohort of high-risk patients. To our knowledge, this is the first time this ratio has been calculated for a cohort of OTRs.