LINAC-based stereotactic radiosurgery to the brain with concurrent vemurafenib for melanoma metastases

Abstract

While selective BRAF inhibitors have demonstrated improved outcomes in patients with metastatic BRAF V600E mutant melanoma, management of brain metastases prior to and during therapy presents challenges. Stereotactic radiosurgery (SRS) is an effective treatment for melanoma brain metastases, but there is limited safety and efficacy data on the use of SRS during BRAF therapy. An analysis was performed of patients with metastatic melanoma and brain metastases treated with SRS while on vemurafenib. MRI scans were reviewed post-SRS to evaluate local control (LC) as well as distant control. We identified 80 metastatic melanoma brain lesions treated in 24 patients. The median planning target volume was 0.28 cm(3) (range 0.05-4.19 cm(3)), and lesions were treated to a median dose of 24 Gy (range 15-24 Gy). The median follow up was 5.1 months (range 2-25.2 months). Eight (10 %) lesions showed progression at a median of 6.1 months (range 2-20.1 months) following SRS. Kaplan-Meier LC estimates at 6 and 12 months were 92 and 75 %, respectively. Fourteen (58 %) patients were noted to have distant brain failure at a median of 3.4 months (range 1.9-16.1 months) following treatment with SRS. Median overall (OS) from the date of SRS was 7.2 months (range 1.5-26.8 months) with a median of 11.9 months (range 1.5-28.5 months) since the date of brain metastases diagnosis. There was no evidence of increased toxicity with the combination of SRS and vemurafenib. SRS to brain metastases appears to be both safe and effective for patients treated concurrently with BRAF inhibitors.