629 Performance monitoring of a streamlined and scalable non-invasive gene expression assay for pigmented lesions

The DermTech Pigmented Lesion Assay (PLA) is a qPCR-based assay that aids in the detection of melanoma by assessing up-regulation two melanoma-associated genes, LINC00518 and PRAME, skin samples collected non-invasive adhesive patches. This study to establish performance characteristics PLA post optimization, investigate prognostic potential comparison qPCR amplification cycle positive with histopathologic diagnoses cutaneous pigmented lesions. RNA isolated from non-invasively cells was analyzed seventy-five optimized simplify laboratory workflow increase scalability through series process improvements including quantification 1-step qRT-PCR (vs. reverse transcription followed qPCR) miniaturization. result determined evaluating PRAME multiplexed housekeeping genes β-Actin PPIA respectively. Samples demonstrated over-expression relative were considered positive. Blinded results, biopsy specimens lesions examined classified dermatopathologist as invasive (n=22); situ (MIS) (n=26); benign nevus (24); or other (n=3). All twenty-two histopathology PLA-positive, an average Ct 32.2 30.9. Seventeen twenty-six MIS 33.8 33.2. Of twenty-seven not melanoma, five 34.4 35.8. results indicate values are highly correlated diagnoses. sensitivity 100% for 65% MIS, overall specificity 81%.