Risk of subsequent primary tumor development in melanoma patients.

Incidence of subsequent malignant tumor development in 740 patients with primary cutaneous melanoma verified between 2006 and 2010 at the Semmelweis University was studied retrospectively and was compared to data of sex and age matched Hungarian population. The follow-up period was 1499 person-years for the whole group from the diagnosis of index melanoma with an average of 2 years. Standardized incidence rate (SIR) was established as the ratio of observed and expected values. The risk of all subsequent malignancies was 15- and 10-fold higher in males (SIR: 15.42) and in females (SIR: 10.55) with melanoma, than in the general population. The increased cancer risk resulted mainly from the significantly higher skin tumor development: SIR values were 160.39 and 92.64 for additional invasive melanoma and 342.28 and 77.04 for subsequent in situ melanoma in males and females, respectively. Non-melanoma skin cancers also notably contributed to the higher risk, the SIR was elevated in both genders to the same extent (males: 17.12, females: 17.55). The risk was also significantly higher for extracutaneous tumor development like chronic lymphocytic leukemia, colon and kidney cancer (both genders), non-Hodgkin's lymphoma, cervical cancer (females), and bladder carcinoma (males). These data underline the importance of patient education and the necessity of frequent medical follow up, including a close-up dermatological screening of melanoma survivors for further malignancies.