Cutaneous malignant melanoma in the Swedish organ transplantation cohort: A study of clinicopathological characteristics and mortality

Background Risk of cutaneous melanoma is increased among organ transplant recipients (OTRs) but outcome has rarely been evaluated. Objective We sought to assess melanoma characteristics and prognosis among OTRs versus the general population. Methods Using Swedish health care registers, we identified melanomas in OTRs (n = 49) and in the general population (n = 22,496), given a diagnosis between 1984 and 2008 and followed up through December 31, 2012. Tumor slides of posttransplantation melanomas were reviewed. Odds ratios for comparison of histopathological characteristics and hazard ratios of melanoma-specific death were calculated. Results Among OTRs the trunk was the most common anatomic melanoma site (50% among female vs 51% among male) and 73% (n = 36) of all melanomas were histologically associated with a melanocytic nevus, 63% (n = 31) atypical/dysplastic. Compared with population melanomas, posttransplantation melanomas were more advanced at diagnosis (Clark level III-V: odds ratio 2.2 [95% confidence interval 1.01-4.7, P  = .03], clinical stages III-IV: odds ratio 4.2 [1.6-10.8, P  = .003]). Risk of melanoma-specific death was increased among OTRs: adjusted hazard ratio 3.0 (1.7-5.3, P  = .0002). Limitations Only posttransplantation melanoma slides were reviewed. Conclusions Melanomas were more advanced at diagnosis and melanoma-specific survival was poorer in OTRs than in the general population. Prophylactic excision of truncal nevi among OTRs may be advised.