Synergy 2.0.

Indications for immunotherapy continue to expand, especially in patients with high incidences of brain metastases. That means clinicians are having to make difficult decisions regarding the timing of stereotactic radiosurgery (SRS) with immunotherapy. A recent report demonstrated that peri-SRS immunotherapy was associated with 2.5x the risk of radiation necrosis. On the flip side, immunotherapy around the time of SRS may also improve efficacy. In this much smaller report of 37 patients with 85 brain mets on immunotherapy for non-small cell lung cancer, concurrent SRS had improved local control (72→ 100%) and distant brain failure (66→ 39%) compared to those receiving immunotherapy only before or after SRS. This supports there is synergy between the two treatments, but the verdict is still out on whether it is more helpful or harmful. TBL: Some prospective data on the use of SRS in conjunction with immunotherapy would be great. | Schapira, Int J Radiat Oncol Biol Phys 2018