Molecular Testing in Resectable Melanoma

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The value of detecting BRAF status in patients with resectable melanoma has not yet been fully defined, since BRAF inhibitors are only indicated for the treatment of patients with unresectable or metastatic disease, notes Merrick I. Ross, MD. Earlier testing is beneficial in the context of clinical trials. At this point, studies are exploring BRAF inhibition in patients with stage IIb/IIc melanoma and in the adjuvant setting, notes Omid Hamid, MD.

In many situations, getting the tissue needed for mutational analysis can be challenging in patients with relapsed melanoma, notes Jeffrey A. Sosman, MD. Moreover, BRAF analysis can take several weeks to complete, which is a long treatment delay for active metastatic disease. As a result, Sosman has begun BRAF testing more frequently in patients with resectable melanoma.

In the future, Jeffrey S. Weber, MD, PhD, believes that every patient with stage III melanoma will likely receive some form of molecular testing. At first this testing will include approximately 20 genes, including NRAS and BRAF. In addition to actionable mutations, gene expression tests are being developed to help identify patients with melanoma at high risk of progression and relapse, suggests Ross. One of these tests, DecisionDX-Melanoma, was compared with sentinel lymph node biopsy and demonstrated that it was capable of accurately predicting which patients would progress, notes Ross.

This test has not yet been fully validated and still requires more clinical data, believes Robert H. I. Andtbacka, MD, CM. Moreover, it remains unclear how results from the test should be interpreted and put into practice. The test seems to show the most value in sentinel lymph node negative patients, believes Ross.