Malignant Melanoma in Solid Transplant Recipients

Abstract

To determine malignant melanoma cause-specific and overall survival among patients with melanoma diagnosed after organ transplantation compared with a national sample with malignant melanoma. Retrospective review. Mayo Clinic sites. Immunosuppressed organ transplant recipients with malignant melanoma identified from surgical and medical databases at Mayo Clinic (1978-2007), the Organ Procurement and Transplantation Network/United Network for Organ Sharing database (1999-2006), and the Israel Penn International Transplant Tumor Registry (1967-2007). Prognostic analyses by Breslow thickness and Clark level of overall and melanoma cause-specific survival. Expected survival rates were estimated by applying the age-, sex-, and calendar year-specific survival rates of patients with malignant melanoma cases reported in the Surveillance, Epidemiology, and End Results Program to the study cohort. Malignant melanoma was diagnosed in 638 patients (724 cases) after transplantation. Breslow thickness was available for 123 patients; Clark level, for 175. Three-year overall survival rates for patients stratified by Breslow thickness (≤ 0.75, 0.76-1.50, 1.51-3.00, and >3.00 mm) were 88.2%, 80.8%, 51.2%, and 55.3%, respectively, and 3-year cause-specific survival rates (95% confidence intervals) were 97.8% (93.7%-100%), 89.4% (76.5%-100%), 73.2% (53.2%-100%), and 73.9% (56.4%-96.6%), respectively. Three-year cause-specific survival rates (95% confidence intervals) for patients stratified by Clark level (I-IV) were 100%, 97.4% (92.4%-100%), 82.8% (65.3%-100%), and 65.8% (51.8%-83.7%), respectively. For patients with Breslow thickness of 1.51 to 3.00 mm and Clark level III or IV, the cause-specific survival rate in the study sample was significantly different from the expected estimates for patients with the same Breslow thickness or Clark level. Compared with the expected survival rates derived from malignant melanoma cases reported in the Surveillance, Epidemiology, and End Results Program, immunosuppressed organ transplant recipients with thicker melanomas (ie, with a Clark level of III or IV or a Breslow thickness of 1.51 to 3.00 mm) had a significantly poorer malignant melanoma cause-specific survival rate. The overall survival rate was worse among patients with a prior history of transplantation, regardless of Breslow thickness or Clark level.