Myriad myPath™ Melanoma

Melanoma is a potentially fatal form of skin cancer. Early and accurate diagnosis of melanoma is critical for long-term survival.1

The analysis of biopsied tissue using a microscope (histopathology) has long been the standard of care for melanoma diagnosis. While it is adequate for diagnosis in most cases, evidence suggests that approximately 10-15% of biopsied melanocytic lesions may be histopathologically ambiguous.2-5 In these situations, microscopic examination may reveal a few features that are characteristic of melanoma but others that are more typical of a benign nevus (‘mole’). As a result, even experienced dermatopathologists occasionally disagree as to whether a given melanocytic lesion is benign or malignant.

Melanocytic lesions continue to pose significant interpretive problems to histopathologists.
Lorenzo Cerroni, et al6

Myriad Genetic Laboratories has developed myPath® Melanoma, a clinically validated test to be used as an adjunct to histopathology when the distinction between a benign nevus and a malignant melanoma cannot be made confidently by histopathology alone.

The test measures the expression of 23 genes by qRT-PCR methodology and distinguishes melanoma from nevi with a sensitivity of 90% and a specificity of 91%. 7

23

Genes by qRT-PCR Methodology

Sensitivity

Specificity

How the myPath Melanoma Test Works

The myPath Melanoma test measures 23 genes for which expression patterns differ between malignant melanoma and benign nevi. These genes are involved in cell differentiation, cell signaling, and immune response signaling.

The genes include:

  • PRAME a single gene involved in cell differentiation
  • S100A7, S100A8, S100A9, S100A12 and PI3, a group of genes involved in multiple cell signaling pathways
  • CCL5, CD38, CXCL10, CXCL9, IRF1, LCP2, PTPRC and SELL involved in tumor immune response signaling
  • Nine housekeeping genes that are measured to normalize RNA expression for analysis

Gene Components

myPath Gene Components

Housekeeping genes included: CLTC, MRFAPI, PPP2CA, PSMA1, RPL13A, RPL8, RPS29, SLC25A3, and TXNLI

numerical-score

An algorithm is applied that combines the measurements of gene expression, assigns a weight to each gene component, and establishes a threshold value.

The result is a single numerical score that classifies a melanocytic lesion as ‘likely benign’, ‘likely malignant’, or ‘indeterminate’.

myPath Melanoma has been clinically validated utilizing rigorous laboratory processes to produce a precise and reproducible result.

myPath Melanoma is currently available to dermatopathologists throughout the country.