Unusually long-term responses to vemurafenib in BRAF V600E mutated colon and thyroid cancers followed by the development of rare RAS activating mutations.

We report two cases showing extreme response to vemurafenib, which could not be predicted prior to treatment commencement. Genetic testing demonstrated a resistant mechanism not previously reported in CRC or PTC patients, namely an acquired mutation of RAS. This is supported by an analysis of a large cohort of BRAF V600E-positive melanomas. Further studies are needed in order to identify predictive markers for response to vemurafenib and to explore novel strategies to overcome RAS-mediated resistance.
PMID: 30036146 [PubMed - as supplied by publisher]

Source: Cancer Biology and Therapy - July 23, 2018 Category: Cancer & Oncology Authors: Ofir Dovrat T, Sokol E, Frampton G, Shachar E, Pelles S, Geva R, Wolf I Tags: Cancer Biol Ther Source Type: research