Melanoma as a subsequent neoplasm in survivors of childhood cancer: A report from the Childhood Cancer Survivor Study.

9510 Background: Survivors of childhood cancer are at increased risk of developing subsequent neoplasms. The incidence and clinical characteristics of subsequent melanoma has not been well described in survivors of childhood cancer. METHODS Analysis included 14,358 5-year survivors of childhood cancer diagnosed between 1970-1986. Cumulative incidence (CIN) of first occurrence of subsequent melanoma (invasive, ocular, or in situ) was estimated. The association of potential risk factors and CIN of melanoma were tested using cause specific hazards models with age as the time scale and censoring at time of death. Risks for subsequent malignant melanoma as compared to SEER data base (excluding in situ and ocular melanomas) were calculated using standardized incidence ratios (SIR) and excess absolute risk (EAR) per 1000 person years. RESULTS 55 survivors reported 61 malignant melanomas (invasive 50, in situ 9, and ocular 2). Median time to tumor development was 20.7 yrs (range 5.6-35.4yrs). Median age at diagnosis of first subsequent melanoma was 32yrs (10.9 - 49.0 yrs) and 28 were male. Initial diagnoses included leukemia (16), lymphoma (15), soft tissue and bone sarcoma (n=15), brain tumor (5), Wilms' tumor (3), and neuroblastoma (1). At last contact, 82% of patients were alive. The CIN of first subsequent melanoma (excluding in-situ and ocular) at 36 yrs from initial cancer was 0.72% (95% CI 0.37-1.07). CIN point estimates by diagnosis ranged from 0.23% for brain tumors to 1.3% for soft tissue and bone sarcoma survivors. The SIR was 2.95 (95% CI 2.19 - 3.89), and EAR was 0.12 (95% CI 0.07 - 0.18) per 1000 person years. Occurrence of melanoma was not associated with age at primary cancer diagnosis, sex, race or family history of cancer. CONCLUSIONS Although the incidence is low, survivors of childhood cancer are at increased risk for developing malignant melanoma. Continued surveillance and awareness of this risk is critical for early detection and treatment of this disease.