Date Published:2016 Feb 29
PURPOSE: To determine the risk of second primary neoplasms (SPNs) in subjects previously diagnosed with uveal melanoma (UM), including an analysis on whether radiotherapy is a risk factor to develop these SPNs. DESIGN: Retrospective cohort study. METHODS: Using the Surveillance, Epidemiology and End Results (SEER) 9 database, we identified patients diagnosed with UM as their first malignancy between 1973 and 2011 (n= 3,976). We obtained standardized incidence ratios (SIR) and excess absolute risks of SPNs on patients with UM compared to a reference population. Multivariate Cox regression models were used to evaluate the effect of radiotherapy in SPNs risk. RESULTS: Sixteen percent (n= 641) of the patients developed SPNs during a median follow-up of 83 months (range: 1 - 463 months). This represented an 11% excess risk compared to the reference population, mainly due to a significantly increased risk of skin melanomas (SIR= 2.93, 95% CI: 2.23 - 3.78) and kidney tumors (SIR= 1.91, 95% CI: 1.27 - 2.76), primarily in those diagnosed between 30-59 years. The occurrence of second UM was also increased (SIR= 16.90, 95% CI: 9.00 - 28.90), which likely includes recurrences misclassified as a second cancer. Radiotherapy was performed in 39% (n= 1,538) of the patients. Multivariate analysis revealed that this treatment was not an independent risk factor for SPNs (Hazard Ratio= 1.06, 95% CI: 0.88 - 1.26, p= 0.54). CONCLUSIONS: Patients with UM presented an 11% higher risk of SPNs compared to the reference population. Radiotherapy does not seem to be a risk factor. SPNs should be considered in the surveillance of UM.