Risk Factors for Melanoma in Renal Transplant Recipients.

Importance: Melanoma risk factors and incidence in renal transplant recipients can inform decision making for both patients and clinicians. Objective: To determine risk factors and characteristics of renal transplant recipients who develop melanoma. Design, Setting, and Participants: This cohort study of a large national data registry used a cohort of renal transplant recipients from the United States Renal Data System (USRDS) database from the years 2004 through 2012. Differences in baseline characteristics between those who did and did not develop melanoma were examined, and a survival analysis was performed. Patients with renal transplants who received a diagnosis of melanoma according to any inpatient or outpatient claim associated with a billing code for melanoma were included. A history of pretransplant melanoma, previous kidney transplantation, or transplantation after 2012 or before 2004 were exclusion criteria. The data analysis was conducted from 2015 to 2016. Exposure: Receipt of a renal transplant. Main Outcomes and Measures: Incidence and risk factors for melanoma. Results: Of 105 174 patients (64 151 [60.7%] male; mean [SD] age, 49.6 [15.3] years) who received kidney transplants between 2004 and 2012, 488 (0.4%) had a record of melanoma after transplantation. Significant risk factors for developing melanoma vs not developing melanoma included older age among recipients (mean [SD] age, 60.5 [10.2] vs 49.7 [15.3] years; P < .001) and donors (42.6 [15.0] vs 39.2 [15.1] years; P < .001), male sex (71.5% vs 60.7%; P < .001), recipient (96.1% vs 66.5%; P < .001) and donor (92.4% vs 82.9%; P < .001) white race, less than 4 HLA mismatches (44.9% vs 37.1%; P = .001), living donors (44.7% vs 33.7%; P < .001), and sirolimus (22.3% vs 13.2%; P < .001) and cyclosporine (4.9% vs 3.2%; P = .04) therapy. Risk factors significant on survival analysis included older recipient age (hazard ratio [HR] per year, 1.06; 95% CI, 1.05-1.06; P < .001), recipient male sex (HR, 1.53; 95% CI, 1.25-1.88; P < .001), recipient white race, living donors (HR, 1.35; 95% CI, 1.11-1.64; P = .002), and sirolimus (HR, 1.54; 95% CI, 1.22-1.94; P < .001) and cyclosporine (HR, 1.93; 95% CI, 1.24-2.99; P = .004) therapy. The age-standardized relative rate of melanoma in USRDS patients compared with Surveillance, Epidemiology, and End Results patients across all years was 4.9. A Kaplan-Meier estimate of the median time to melanoma among those patients who did develop melanoma was 1.45 years (95% CI, 1.31-1.70 years). Conclusions and Relevance: Renal transplant recipients had greater risk of developing melanoma than the general population. We believe that the risk factors we identified can guide clinicians in providing adequate care for patients in this vulnerable group.