Surveillance for melanoma by dermatologists rather than primary care or other physicians correlates with diagnosis at an earlier stage and a higher five-year survival rate, according to an article in the April issue of Archives of Dermatology.

Estimates suggest that melanoma will affect 1 in 52 men and 1 in 77 women in the United States during their lifetimes, according to background information in the article. If melanoma is removed at an early stage (less than 1 millimeter thick), patients have a 90 percent cure rate. However, metastatic melanoma usually requires both surgery and chemotherapy and carries five-year survival rates less than 20 percent.

Michelle L. Pennie, MD, Emory University School of Medicine, Atlanta, and colleagues attempted to determine whether a difference in outcome based on specialty of the physician providing screening using data from two sources: a US government database and a National Cancer Institute (NCI) database that includes information about patients' demographics, date of diagnosis, stage of cancer at diagnosis and date of death.

The researchers linked records from the two databases for 2,020 patients, comparing codes for different kinds of physician visits in the one database to cancer diagnoses and outcomes recorded in the other database.

Of 2,020 patients, 1,467 (73 percent) were diagnosed with melanoma by a dermatologist and 553 (27 percent) were diagnosed by a physician in another specialty. Tumors diagnosed by dermatologists were thinner on average than those diagnosed by non-dermatologists (0.86 millimeters versus 1.0 millimeter).

"We also looked at melanoma stage at diagnosis and observed significant differences between provider types, with a preponderance of thin melanoma (stage 0 or stage I or II) in the dermatologist group and a preponderance of thick melanoma (stage III or stage IV) in the non-dermatologist group," the authors wrote.

After six months, two years and five years, patients whose cancer was diagnosed by a dermatologist had a higher survival rate than those diagnosed by a non-dermatologist. The two-year and five-year survival rates were 86.5 percent and 73.9 percent for the dermatologist group compared with 78.8 percent and 68.7 percent for the non-dermatologist group.

Analysis of mortality by cause showed the two groups had similar non-cancer-related mortality rates. However, the dermatologist group had lower cancer-related mortality rates and a lower overall mortality rate.