Performance of the 23-gene expression profile (23-GEP) test by histopathological evaluation in an independent, multi-center performance cohort of cutaneous melanocytic neoplasms

Summary: These performance metrics do not deviate appreciably from previous studies and demonstrate that the 23-GEP is highly accurate, further supporting its use as an ancillary test which is integrated with clinical, histopathological, and other ancillary test information to guide the final diagnosis. › Higher rates of non-concordant diagnoses were present in lesions where 23-GEP differed from dermatopathologists’ majority assessment, which calls into question the true malignant potential. › This study relies on subjective histopathologic interpretation without outcomes which allows for larger cohort analyses. Studies utilizing outcomes have confirmed the accuracy of 23-GEP.7-9