Incidence and characteristics of melanoma brain metastases appearing during vemurafenib treatment

9042 Background: Melanoma brain metastases are frequent and severe. We studied their characteristics in a retrospective cohort of patients treated with vemurafenib, a BRAF inhibitor indicated in V600-mutant metastatic melanoma. Methods: We included in this study all patients receiving vemurafenib in our department between November 2010 and November 2013 without melanoma brain metastases at initiation of treatment. Brain scans were performed after 2 months, and then every 3 months or in case of neurologic symptoms. RMI could be performed to confirm scan result. Our primary endpoint was the brain metastases incidence. Secondary endpoints were associated risk factors, onset modalities and clinical evolution. Results: In our cohort of 86 patients, incidence of brain metastases was 20% after a median follow-up of 9 months (1 to 26 months). They appeared after a mean of 5.3 months of vemurafenib exposure (1 to 15 months). The only identified risk factor was a high number of metastases before treatment (p=0.045)...