Expanded RAS: Refining the Patient Population

The era of precision medicine has changed the treatment paradigm for some cancers, but for others, the term precision is a stretch. New targets and therapies have broadened choices for patients with lung cancer or melanoma; however, in colorectal cancer (CRC), for example, the evolution of biomarkers has been primarily to inform whom not to treat rather than to identify the patients who will benefit from treatment. The refinements in CRC have been limiting rather than expansive; by broadening the definition of RAS mutations, fewer patients have multiple targeted options.