Patients with a family history of multiple melanoma skin cancer are at increased risk of multiple primary melanomas, according to a study in the October 5 issue of JAMA: The Journal of the American Medical Association.
In 2005, there will be an estimated 62,000 new cases of invasive melanoma and an estimated 7,600 deaths due to melanoma in the United States, according to background information in the article. Melanoma is the fifth leading cancer in men and the sixth leading cancer in women in the United States. The incidence of melanoma continues to rise at about 3 percent per year in the United States, with an estimated lifetime risk for an individual of 1.4 percent. This increasing incidence puts a larger portion of the population at risk not only for one primary melanoma but also for subsequent primary melanomas.
Cristina R. Ferrone, M.D., and colleagues from Memorial Sloan-Kettering Cancer Center, New York, conducted a study to identify the incidence and characteristics of patients at risk of developing multiple primary melanomas (MPM). The study included 4,484 patients diagnosed with a first primary melanoma between January 1, 1996, and December 31, 2002.
The researchers found that 385 patients (8.6 percent) had 2 or more primary melanomas, with an average of 2.3 melanomas per MPM patient. Seventy-eight percent had 2 primary melanomas. For 74 percent of patients, the initial melanoma was the thickest tumor. Fifty-nine percent presented with their second primary tumor within 1 year. Twenty-one percent of MPM patients had a positive family history of melanoma compared with only 12 percent of patients with a single primary melanoma (SPM). Thirty-eight percent of MPM patients had dysplastic nevi (DN; atypical moles) compared with 18 percent of SPM patients.