In focus.

Top Line: Is stereotactic radiosurgery (SRS) a safe option for patients with small cell lung cancer (SCLC) brain metastases?

The Study: Roughly half of patients with SCLC develop brain metastases at some point in the course of their disease. As a result, prophylactic whole brain radiation (WBRT) has been an important part of treatment for SCLC for decades. But does a higher likelihood of developing brain mets from SCLC mean that intracranial metastatic disease behaves differently from other histologies? There is limited data on this topic. While focal stereotactic radiation (SRS) has become the standard for patients with “limited” brain metastases, many assume that if prophylactic WBRT is effective for SCLC, then therapeutic WBRT is standard for SCLC brain metastases. This systematic review and meta-analysis of 7 studies evaluated overall survival following WBRT with or without SRS boost and SRS for SCLC brain metastases. Obviously, the SRS alone group was a select minority of patients (8.5% of >16,000 patients), and overall survival was better after SRS than after WBRT. The authors stress that this doesn’t imply SRS results in superior survival, but it does provide strong evidence that SRS is not detrimental. In fact, median OS after first-line SRS was estimated at 8.7 months. At 12 months, local and distant brain control rates were 78% and 58%, which are comparable with rates seen in other histologies. These findings also held true among patients who had not received prior PCI. 

TBL: Among select patients, survival and intracranial disease control after SRS appear comparable to those treated with WBRT. | Gaebe, Lancet Oncol 2022