Pigmented Lesion Assay:
Melanoma Associated Gene Expression
The pigmented lesion assay provides physicians with a non-invasive option for the biopsy of clinically atypical pigmented lesions using an adhesive patch rather than a scalpel.
“The noninvasive pigmented lesion assay enables
dermatologists to biopsy fewer benign pigmented
skin lesions while missing fewer melanomas.
This result may increase the number of early
melanomas biopsied and reduce the number of benign
lesions biopsied, thereby improving patient outcomes
and reducing healthcare cost.” JAMA 2017
DermTech’s PLA can distinguish melanoma from benign pigmented skin lesions such as nevi or moles with a negative predictive value (NPV) of over 99%, sensitivity of 91%, and specificity of 69%, without the need for an invasive biopsy. The PLA has advantages in patient comfort and convenience as well as additional utility in patients who have multiple lesions, especially in cosmetically sensitive areas, are anti-coagulated, at increased risk for infection or scarring, or who are at risk for wound healing complications. Evidence is also increasing that the detected gene expression changes precede morphologic changes. (JAMA 2017)
Skin cancer is the most common form of cancer in the U.S., and its deadliest form, melanoma, is responsible for nearly 10,000 deaths each year. The number of melanomas diagnosed has been growing up to 7% each year among fair-skinned populations. If caught in early stage, when a lesion is less than a millimeter deep, the prognosis is good, but once lesions develop to a depth over four millimeters, the five-year survival drops to <50%. For this reason, classifying pigmented skin lesions early and efficiently can have a significant impact on physician practice and patient outcomes.
DermTech has identified a specific gene expression ‘signature’ test that is highly correlated with melanoma.2,3 DermTech’s Pigmented Lesion Assay (PLA) uses stratum corneum tissue collected with adhesive patches included in our Non-Invasive Skin Biopsy Kit.
With the current standard of care, a patient who has one or two melanomas in his or her lifetime might undergo ten biopsies or more. Using the PLA and Non-Invasive Skin Biopsy Kit, a skin sample is collected with adhesive patches, rather than a surgical biopsy, and then sent to DermTech for analysis. The PLA reliably differentiates between gene expression patterns consistent with melanoma and non-melanoma.
When Should I Test?
The PLA test is intended for use on pigmented skin lesions, which are clinically suspicious for melanoma. These lesions may meet one or more ABCDE criteria.
PLA uses include:
- Lesions being followed for change
- Lesions in cosmetically sensitive areas
- Lesions on patients with potential contraindications to surgical biopsy including patients that are anti- coagulated, those at risk for infection, and those at risk for poor wound healing or elevated abnormal scarring
Adhesive Skin Biopsy Collection Kit:
The unique properties of the adhesive patches allows for the collection of skin samples with minimal patient discomfort and recovery time, while maximizing the collection of tissue for our PLA. A single kit contains all of the necessary components to complete the non-invasive biopsy:
- Adhesive patches
- Instructions for use
- Marking pen for outlining the lesion
- Pre-paid FedEx shipping pack
The Test – See Your Diagnosis Differently with Non-Invasive Gene Expression
DermTech’s PLA MAGE (Melanoma Associated Gene Expression) detects the expression for two specific genes, PRAME and LINC00518. These two genes belong to separate classes of molecules that are known to have roles in oncogenesis, and both are elevated in melanoma. These gene expression results are summarized in a molecular pathology report.