Eradication of BRAF K601E Mutation in Metastatic Castrate-resistant Prostate Cancer Treated With Cabazitaxel and Carboplatin: A Case Report

Mutations in the BRAF gene are associated with a variety of human cancers. Patients with BRAF mutations represent a rare but clinically significant group of metastatic castrate-resistant prostate cancers, with K601E alterations being the most common type of BRAF mutation. Limited data is available on the best course of treatment for patients with BRAF K601E prostate cancer. Guardant 360 circulating tumor DNA (ctDNA) analysis was used to identify and monitor the presence of BRAF K601E mutation in patients with metastatic castrate-resistant prostate cancer treated at Tulane Cancer Center. Two patients with metastatic castrate-resistant prostate cancer were found to have positive BRAF K601E mutations. One patient exhibited an excellent response to treatment with cabazitaxel and carboplatin, which lead to the eradication of the ctDNA BRAF K601E mutation while undergoing treatment. The other patient failed treatment with abiraterone, taxotere, and a trial ERK inhibitor and passed away. Cabazitaxel and carboplatin therapy can be used for patients with prostate cancer with BRAF K601E mutation. Although this report only involves 2 patients, it could be used to guide treatment for patients with BRAF K601E prostate cancer who have failed other treatment regimens. This report also highlights the utility of ctDNA testing in guiding patient care. (C) 2019 Elsevier Inc. All rights reserved.