DermTech, Inc. presented a late breaking abstract—“Validation of Noninvasive Gene Expression (PLA) Against High Risk Driver Mutations (BRAF, NRAS, and TERT) in Cutaneous Melanoma” —at the 76^th Annual Meeting of the American Academy of Dermatology (AAD) in San Diego.

The late breaking research by Clay Cockerell, MD, of Cockerell Dermatopathology in Dallas, validated the high performance of the Pigmented Lesion Assay (PLA) against key driver mutations in melanoma. These mutations are found to correlate with histopathologic criteria on prognosis. Ninety-seven percent of the histopathologically confirmed melanoma samples were either PLA positive or mutation positive. Statistically significant differences in mutation frequency were observed between melanoma positive/PLA positive and melanoma negative/PLA negative samples for hotspot mutations (75% vs. 15%, p<<0.0001). Mutations in the adhesive patch samples were also concordant with mutations in FFPE tissue blocks.

Real-world PLA results in more than 500 patients showed that 89 percent of PLA negative results were mutation negative, while 60 percent of PLA positive results were mutation positive, demonstrating that PLA positive tests identify high-risk lesions with driver mutations, while PLA negative tests do not harbor these mutations.

“The diagnosis of early stage melanoma can be challenging histopathologically and has a discordance rate as high as 27 percent. This study demonstrated that gene expression and mutation analyses can provide valuable objective information when assessing difficult pigmented lesions,” said Dr. Cockerell.

“This work further validates the PLA for the non-invasive identification of melanoma risk. In addition, it conforms the high real-world performance of the test and accuracy to rule out melanoma risk in pigmented lesions. This work also provides the foundation for our Nevome product, which will help physicians manage lesions with atypical histopathology findings, improve risk stratification, and provide valuable prognostic information. DermTech’s PLA and Nevome are rapidly becoming the standard for assessment of pigmented lesions,” said John Dobak MD, DermTech’s CEO.