Survival of melanoma patients treated with targeted therapy and immunotherapy after systematic upfront control of brain metastases by radiosurgery.

Background: Targeted therapy (TT) and immunotherapies (ITs) have dramatically improved survival in metastatic melanoma (MM). However, their efficacy on brain metastasis (BM) remains limited and poorly documented.

Patients And Methods: Retrospective cohort of consecutive MM patients (pts) with BMs, all systematically upfront treated by Gamma-Knife (GK) at first BM and retreated in case of new BMs, from 2010 to 2015 at the time when ipilimumab BRAF ± MEK inhibitors and anti-PD1 were introduced in practice. Survival after 1st GK (OS) according to prognostic factors and treatment.

Results: Among 179 consecutive pts treated by GK, 109 received IT and/or TT after the 1st GK. Median OS was 10.95 months and 1- and 2-year survival rates were 49.5% and 27.4%, respectively, versus a median overall survival (OS) of 2.29 months (p < .001) in those who did not receive IT or TT. In pts who initially had a single BM, median OS and 1- and 2-year survival rates were 14.46 months, 66.7% and 43.4%, respectively; in pts with 2-3 BMs: 8.85 months, 46.4% and 31%, respectively; in pts with >3 BMs: 7.25 months, 37.2% and 11.9%, respectively. Multivariate analysis for OS confirmed that IT and TT were significantly and highly protective. Best OS was observed in BRAF-wild-type pts receiving anti-PD1 or in BRAF-mutated pts receiving BRAF-inhibitors and anti-PD1 (12.26 and 14.82 months, respectively).

Conclusion: In real-life MM pts with BMs, a strategy aiming at controlling BM with GK together with TT and/or TT seems to achieve unprecedented survival rates.