Real-World Performance of a Noninvasive Cutaneous Melanoma Rule-Out Test: A Multicenter U.S. Registry Study

Abstract

Introduction: Non-invasive adjuncts to visual assessment of pigmented lesions may reduce biopsies of benign lesions without compromising melanoma detection. A non-invasive genomic melanoma rule-out assay analyzes RNA extracted from stratum corneum cells for PRAME and LINC00518, two genes commonly expressed in melanomas but less often in benign lesions. This study sought to characterize performance of this test in a large patient cohort tested in the real-world clinical setting. Methods: The test was applied to suspicious pigmented skin lesions at 63 U.S. dermatology and primary care practices. Test results (positive / negative) were compared to pathology diagnoses (melanoma / not melanoma) for lesions that were biopsied and to follow-up visual examination for those that were monitored. Results: Of 19,653 total lesions evaluated, 17,858 (90.87%) tested negative. Biopsy results and / or follow-up examinations were available for 5,096 lesions, with median and mean follow-up duration of 352 and 341 days, respectively. For melanoma, sensitivity was 95.8% and specificity was 69.4%. Positive predictive value (PPV) was 13.4%, and NPV was 99.7%. For melanoma and ‘borderline’ lesions combined, sensitivity was 94.2%, specificity was 71.2%, PPV was 20.8%, and NPV was 99.3%. Conclusion: The results suggest this noninvasive test can facilitate distinction of melanoma from its benign simulators, increasing the proportion of pigmented lesions that can be safely managed with surveillance rather than biopsy and/or excision.