The incidence of new primary tumors in advanced melanoma patients

This study evaluated the incidence of new primary melanomas (NPM’s) after first diagnosis of advanced melanoma.

Melanoma occurs when damaged skin cells multiply rapidly and form tumors. Patients diagnosed with melanoma are at an increased risk of forming new melanoma tumors (NPM's) compared to the general population. Recent studies have suggested that BRAF inhibitors (drugs used to treat patients with a mutation in the BRAF gene, a mutation occurring in approximately 50% of melanomas) increase the risk of developing NPM’s. However, high grade evidence is lacking regarding the incidence of NPM's among advanced melanoma patients. This study evaluated the incidence of NPM’s among patients diagnosed with Stage III or stage IV melanoma, regardless of drug use (such as treatment with BRAF inhibitors).

5,963 patients diagnosed with advanced melanoma were followed in this study. 4215 patients were diagnosed with stage III melanoma while 1748 were diagnosed with stage IV melanoma.

Overall, 5% of stage III patients and 1% of stage IV patients developed NPM's. The majority of patients developed a single NPM. The majority of NPM's developed more than one year following the initial diagnosis. Factors associated with the development of a NPM's include male sex and an initial melanoma site of the head, neck or trunk. A history of multiple lesions at the time of diagnosis was also found to be associated with a higher risk of developing NPM's.

This study concluded that patients with advanced melanomas remain at an increased risk of developing new primary melanomas. Initial tumor location and number, as well as patient sex, influence the risk of developing new primary melanomas.

The possible effects of different cancer treatments received were not accounted for in this study.

Consult with your physician regarding the importance of frequent skin inspections for the early detection of new primary melanomas.