The risk of developing a second, different, cancer among 14560 survivors of malignant cutaneous melanoma: a study by AIRTUM (the Italian Network of Cancer Registries)

The aim of this study was to provide further quantitative data on the risk of second nonmelanoma cancers in patients with cutaneous malignant melanoma (CMM). A cohort of 14 560 population-based patients from the Italian Network of Cancer Registries incident during 1985-2002 were included and followed up for further incident cases and vital status. Standardized incidence ratios (SIR) were used to compare the number of observed second cancers with expected cancers. In a total of 69 581 person-years, 1020 second cancers were registered, of which 804.6 were expected (SIR=1.27; 95% confidence interval 1.19-1.35). The risk was similar for males and females, (SIR= 1.27 and 1.26, respectively). The risk was slightly higher among younger (<60 years; SIR=1.44) than older (60+ years; SIR=1.19) patients. The overall risk in the period after CMM diagnosis did not change significantly (SIR=1.34 during the first 5 years and 1.12 afterwards). No differences in the overall risk were evident in different years of diagnosis, for different melanoma morphology types or for different geographical areas within Italy. Statistically significantly increased risks were found for nonmelanoma skin cancers [observed number (n)=362, SIR=3.12], for bone (n=5, SIR=6.08) and for kidney cancers (n = 39, SIR=1.95) and lower than expected risks were found for liver (SIR=0.46) and lung cancers (SIR=0.71). We confirm that CMM patients are at high risk for nonmelanoma skin cancers. The reasons for the increased risk of kidney and bone cancers are not yet clear.