MONDAY, Dec. 19 (HealthDay News) -- A new study finds that cancer survivors are at increased risk for cutaneous melanoma, one of the most aggressive forms of skin cancer. The highest risk is among those previously diagnosed with melanoma.

Cutaneous melanoma is the fifth most commonly diagnosed cancer in U.S. men and the seventh most commonly diagnosed cancer in U.S. women. Incidence of the cancer is increasing, and death rates from the disease have decreased little, despite survival gains for other types of cancer, according to background information in the study.

Ultraviolet radiation exposure is the greatest risk factor for cutaneous melanoma, but race and genetics also influence the risk.

In this study, researchers analyzed data from about 70,800 U.S. patients who were diagnosed with cutaneous melanoma as a first primary cancer (median age of 54 at time of diagnosis) and 6,353 patients who were diagnosed with cutaneous melanoma (average age of 70 at time of diagnosis) after surviving a previous cancer.

Patients with a previous melanoma diagnosis were more likely to develop cutaneous melanoma, said Geoffrey B. Yang, a medical student at Case Western Reserve School of Medicine, in Cleveland, and colleagues.

Among patients younger than 45 at first cancer diagnosis, 777 developed cutaneous melanoma. Those at significantly higher risk included those previously diagnosed with cutaneous melanoma or other skin cancers, Kaposi sarcoma, breast cancer or lymphoma.

Among patients who were 45 or older at first cancer diagnosis, the risk of developing cutaneous melanoma was much higher among those previously diagnosed with cutaneous melanoma or other skin cancers, ocular melanoma, breast cancer, prostate cancer, lymphoma and leukemia.

"Characteristics associated with better survival in both (groups) included female sex, age younger than 45 years at melanoma diagnosis, being married, being white vs. black, decreasing Breslow depth [how deeply tumor cells have invaded], lack of tumor ulceration, no nodal involvement, and absence of metastases [the spread of cancer from the primary tumor to other locations in the body]," the researchers wrote in a journal news release.

The results suggest the need for continued skin surveillance in melanoma survivors, they concluded.

The study appears in the December issue of the journal Archives of Dermatology.

Dr. Michele Green, a dermatologist at Lenox Hill Hospital in New York City, said that people tend to think of melanoma "as 'lightening doesn't strike twice,' but unfortunately, there are both genetic and environmental reasons which make this a faulty comparison. A history of malignant melanoma makes you at an increased risk for a second primary melanoma and [you] definitely need constant monitoring.

"This risk remains elevated for over 15 years. This was a very important study which illustrated what I have seen in private practice over the past 20 years," she added.

More information

The U.S. National Cancer Institute has more about melanoma and other skin cancers.