BOSTON – Although skin biopsy remains the gold standard for diagnosing early-stage melanoma, advances in genetic expression profiling are helping dermatologists provide a nuanced approach to managing suspicious lesions.
One such test, the Pigmented Lesional Assay (PLA) uses adhesive patches applied to lesions of concern at the bedside to extract RNA from the stratum corneum to help determine the risk for melanoma.
Dr Caroline Kim
At the annual meeting of the American Academy of Dermatology, Caroline C. Kim, MD, director of melanoma and pigmented lesion clinics at Newton Wellesley Dermatology, Wellesley Hills, Mass., and Tufts Medical Center, Boston, spoke about the PLA, which uses genetic expression profiling to measure the expression level of specific genes that are associated with melanoma: PRAME (preferentially expressed antigen in melanoma) and LINC00518 (LINC). There are four possible results of the test: Aberrant expression of both LINC and PRAME (high risk); aberrant expression of a single gene (moderate risk); aberrant expression of neither gene (low risk); or inconclusive.
Validation data have showna sensitivity of 91% and a specificity of 69% for the PLA, with a 99% negative predictive value; so a lesion that tested negative by PLA has a less than 1% chance of being melanoma. In addition, a
