Large skin lesions more likely to be melanoma

May 6, 2008

New York - A new study reveals that large skin lesions are more likely than smaller ones to be melanoma, HealthDay News reports.

New York - A new study reveals that large skin lesions are more likely than smaller ones to be melanoma, HealthDay News reports.

The study, conducted by researchers at the New York University School of Medicine and published in the April issue of Archives of Dermatology, suggests that lesions larger than 6 mm in diameter should be screened for melanoma, thus supporting the current use of diameter guidelines for such screenings.

Investigators studied more than 1,300 patients undergoing biopsies for 1,657 pigmented skin lesions or markings suggestive of melanoma. Of those lesions, 804, or 48.5 percent, were larger than 6 mm in diameter; 138 (8.3 percent) were diagnosed as melanoma.

With each one-millimeter diameter range from 2.01 to 6 mm, the proportion of melanomas did not vary significantly, remaining stable at 3.6 percent to 4.5 percent, the authors write.

But they observed a nearly 100 percent increase in the proportion of melanomas when comparing the 5.01- to 6-mm category - 4.3 percent - to the 6.01- to 7-mm category, or 8.3 percent, HealthDay News reports.

As a result, the authors recommend that a diameter criterion of larger than 6 mm remain a part of the ABCDE criteria - the screening method based on asymmetry, border irregularity, color variegation, diameter larger than 6 mm, and lesion changes.

The authors acknowledge that some experts say strict adherence to the diameter guideline may cause doctors to miss smaller melanomas.