Development of a novel noninvasive adhesive patch test for the evaluation of pigmented lesions of the skin.

BACKGROUND: The accurate clinical assessment of melanocytic neoplasms is a challenge for clinicians. Currently, obtaining a biopsy specimen and conducting a histologic examination is the standard of care. The incidence of melanoma in white populations is high, resulting in a large number of biopsy specimens.

OBJECTIVE: The objective of this study is to develop a noninvasive genomic method using mRNA to classify pigmented skin lesions as either benign or malignant.

METHODS: An adhesive patch method was used to obtain cells from the surface of melanocytic lesions. mRNA was extracted and a genomic signature was formulated in a training set of benign and malignant melanocytic neoplasms and subsequently tested in a validation set.

RESULTS: A 2-gene signature assessing the expression levels of CMIP and LINC00518 was able to differentiate melanomas from nevi in an independent validation set of 42 melanomas and 22 nevi with a sensitivity of 97.6% and specificity of 72.7%.

LIMITATIONS: Larger and more diverse sets of melanomas and nevi are needed for additional validation of the molecular expression profiling in various subsets of melanocytic neoplasms.

CONCLUSION: Our data suggest that mRNA molecular signatures can serve as a highly useful noninvasive method of differentiating melanoma from nevi and decrease the number of unnecessary biopsies.