Risk of second primary malignancies among survivors of cutaneous melanoma: A nationwide population-based study in the Republic of Korea

There is limited data on the risk of second primary malignancies (SPMs) in Asian melanoma survivors. This study aimed to identify the risk of SPMs in Asian melanoma survivors. Standardized incidence ratios (SIRs) were calculated for overall and specific SPMs. The risk factor for overall SPM development was analyzed using a multivariable Cox regression model. A total of 10,070 patients with melanoma were included in the study. Melanoma survivors exhibited an increased risk of overall SPM (SIR, 1.51; 95% confidence interval [CI], 1.34-1.70). Additionally, specific SPMs were more common among melanoma survivors, including nonmelanoma skin cancer, oral cavity and pharyngeal cancer, renal cancer, female breast cancer, lung cancer, pancreatic cancer, and liver cancer. Independent risk factors for overall SPM development included a Charlson Comorbidity Index >= 1 (adjusted hazard ratio [aHR], 1.41; 95% CI, 1.07-1.87), and a body mass index >= 25 kg/m2 (aHR, 1.47; 95% CI, 1.04-2.08). Inherent uncertainty related to diagnostic codes may exist. The risk of overall and specific SPMs was significantly elevated in Asian melanoma survivors, particularly among those with invasive melanoma. Among modifiable factors, a high body mass index (BMI) was associated with an increased risk of SPM.