Salivary gland cancers are a heterogeneous collection of malignancies defined primarily by different histologies, which include adenoid cystic carcinoma (ACC), mucoepidermoid carcinoma, and salivary duct carcinoma (SDC). In particular, SDC is a neoplasm known for both its poor prognosis and its rarity. Because of these characteristics, data are currently insufficient to confidently recommend a standard of care for these tumors.
Recently, clinical oncologists have had increasing access to tumor genomic profiling, which allows for identification of mutations, gene fusions, and copy number variants that may predict response to specific targeted therapies. This approach has been of particular interest in so-called difficult-to-treat cancers, which include rare malignancies such as SDC, that have a very limited evidence base to guide treatment decisions. This report presents a patient with a widely metastatic SDC harboring a BRAF p.V600E mutation that was treated with a precision oncology approach developed in conjunction with the University of Alabama at Birmingham (UAB) Molecular Tumor Board (MTB).1 To our knowledge, this is the first reported use of combined BRAF and MEK inhibition for the treatment of metastatic BRAF-mutated SDC in the frontline setting.
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