Genomic Evaluation of Clinically Ambiguous Pigmented Lesions

The clinical evaluation of pigmented lesions represents a 'high-stakes' scenario as a missed melanoma can be fatal. Traditional clinical assessment visually sorts pigmented lesions into those that merit a biopsy and those that do not. In our practice there exists a group of lesions judged to not merit biopsy where melanoma, while very unlikely, cannot be excluded with absolute certainty. These ambiguous pigmented lesions (APLs) were often photographed and followed for clinical evolution. This article evaluates the presence of APLs and describes the use of non-invasive genomic testing to sort them. An informal survey using pictures of 10 APLs found that 6 of 8 dermatology providers were unable to identify which were melanomas. Next, our single practice chart review of 1,254 APLs evaluated by non-invasive genomic testing revealed 35 melanomas. All 1,254 were lesions that fell below our biopsy threshold. Non-invasive genomic testing can improve biopsy decisions particularly in clinically indeterminate pigmented lesions.