Dermoscopy helps differentiate benign melanocytic lesions vs. melanoma

Dermoscopy allows for thorough observation of morphologic features not visible to the naked eye in melanoma screening, according to a speaker at the South Beach Symposium Medical Dermatology Summit.

“[Dermoscopy] is a noninvasive diagnostic technique that has become very popular. It does allow for observation of features that are not visible to the naked eye using colors and structures,” David J. Goldberg, MD, JD, of Skin Laser & Surgery Specialists of New York and New Jersey and Icahn School of Medicine at Mount Sinai, said. “It does differentiate between melanocytic and non-melanocytic lesions as well as benign or malignant neoplasms. The most widely used dermatoscope, because there are plenty on the market, has a tenfold magnification.”

In dermoscopy, each color corresponds to a different structure in the skin, with pigment appearing in different shades to indicate depth. Assessing for benign melanocytic lesions vs. melanoma requires pattern recognition, Goldberg said. Benign melanocytic lesions have a reticular pigment network of brown interconnected lines, while melanoma lesions have an atypical pigment network characterized by irregularity in shape, size and color. For further differentiation and melanoma diagnosis, Goldberg suggested using the Menzies scoring method.

“To diagnose melanoma, the lesion must have neither negative features and one or more positive features,” Goldberg said. “The negative features, which you do not expect to see in melanoma, are symmetry and presence of a single color. ... All the positive features that I talked about, all the dots, the radial streaming, these are the things seen under dermoscopy in melanoma.”