New Test Measures Risk of Metastasis for Early-Stage Melanoma

The gist: A new test helps measure the risk of metastasis for early-stage melanoma patients. The test, called DecisionDx-Melanoma, is a molecular test that measures the activity of 28 genes. Based on the results of the test for a given patient, a doctor may make certain treatment suggestions for that patient.

“Because two-thirds of melanoma patients who die or experience metastatic disease are initially diagnosed with early-stage disease, it is important to determine risk for metastasis in patients with early-stage melanoma. About 75% of patients with melanoma have early disease (stage I or II) at diagnosis.

“A prognostic 28-gene signature (DecisionDx-Melanoma, Castle Biosciences) could predict which patients with stage I or II melanoma are at high risk for metastasis, and could alter the clinical management of these patients, according to a confirmatory study published in the January 1 issue of Clinical Cancer Research.

“The 28-gene signature predicts a patient’s risk for metastasis, independent of American Joint Committee on Cancer (AJCC) melanoma staging, Breslow thickness, ulceration, mitotic rate, and age.”

Study Shows Castle Biosciences’ Gene Expression Profile Test Successfully Identified High Risk Disease in a Cohort of 217 Melanoma Patients Who Underwent Sentinel Lymph Node Biopsy

“Castle Biosciences Inc. today announced results of a 217-patient study demonstrating that its gene expression profile (GEP) test, DecisionDx-Melanoma, identified primary cutaneous (skin) melanoma tumors that were sentinel lymph node biopsy negative but were at high risk of metastasis. The GEP test also identified tumors that were unlikely to become metastatic, independent of nodal status. The data are being reviewed today at the 50th Annual Meeting of the American Society of Clinical Oncology (ASCO) in the Melanoma/Skin Cancers Poster Highlights Session by David H. Lawson, M.D., Professor of Hematology and Medical Oncology, Winship Cancer Institute, Emory University.”

Editor’s note: More and more, doctors are using molecular testing methods to make diagnoses and guide treatment decisions. Now, molecular testing may be able to help determine whether a melanoma tumor is likely to metastasize (spread to other parts of the body). A procedure called sentinel lymph node biopsy is commonly used to measure the severity of a melanoma diagnosis; a “negative” sentinel node biopsy indicates low risk of metastasis. But some patients with negative sentinel node biopsies still go on to experience metastasis. A new molecular test called DecisionDx-Melanoma can identify cutaneous melanoma tumors that are at risk of metastasizing, regardless of sentinel node biopsy results. The test analyzes the activity of 31 genes in a tumor to determine risk of metastasis.

Study Strengthens Validity of Genetic Test for Whether Melanomas Will Spread

In keeping with previous findings, the latest study on a new genetic test confirms that it can predict whether melanomas will spread. These results were presented at the American Academy of Dermatology meeting. While survival rates are generally high for people with melanomas that have not yet spread, metastases do occur in about 14% of this group. The test, called DecisionDx-Melanoma, classifies people as either low or high risk of metastasis based on the activity of 31 genes in their tumors. To date, the test has been validated using follow-up data on 400 people with early-stage melanomas. Knowing which people are likely to develop melanoma tumors in other parts of their bodies will help doctors tailor their long-term care appropriately.


Genetic Test Accurately Predicts Risk That Melanomas Will Spread

New research shows that a genetic test catches more melanomas that are likely to spread than conventional staging methods, which are based on what tumors look like. Melanomas metastasize in nearly 15% of people diagnosed with tumors that have not yet begun to spread. Developed by Castle Biosciences, the test is called DecisionDx-Melanoma and it uses the activity of 31 genes to classify melanomas as high or low risk of metastasis. The researchers analyzed more than 400 melanomas that had not even begun to invade nearby tissues, which are currently thought to be low risk. But the test classified some of them as high risk, and the researchers found that 72% of these melanomas spread within 5 years of diagnosis. These findings were presented at the American Society of Clinical Oncology’s 2013 meeting. The researchers recommend monitoring and treating these high-risk patients more aggressively.