Care Patterns for Stereotactic Radiosurgery in Small Cell Lung Cancer Brain Metastases

Introduction: The historical standard of care for brain metastases (BMs) from small cell lung cancer (SCLC) has been whole-brain radiotherapy (WBRT). However, there is growing interest in upfront stereotactic radiosurgery (SRS) for select SCLC patients. Materials and Methods: We invited United State-based Radiation Oncologists (ROs) via email to answer an anonymous survey using a branching logic system addressing their use of SRS and WBRT for SCLC BMs. Wilcoxon rank-sum test and Fisher's exact test were used to compare differences in continuous and categorical variables, respectively. Multivariable logistic regression analyses were fitted for outcome variables including covariates with P < .10 obtained on univariable analysis. Results: In total, 309 ROs completed the survey and 290 (95.7%) reported that they would consider SRS for SCLC BMs under certain clinical circumstances. Across patient characteristics, the number of BMs was the most heavily weighted factor (mean 4.3/5 in importance), followed by performance status, cognitive function, and response to prior therapy. Fewer BMs were correlated with increased SRS use (55.8% offered SRS “very frequently” [>75% of cases] or “often” [51%-75% of cases] for 1 BM vs. 1.1% for >10 BM, P < .001). In situations where WBRT was preferred, concern for rapid intracranial progression (45.3%) and lack of high-level data (36.9%) were the most important factors. The majority (60.6%) were aware of a large recent international retrospective analysis (the FIRE-SCLC study) reporting similar OS between upfront SRS and WBRT; awareness of this study was the only respondent variable predictive of SRS use for limited BMs (19.2% of those aware of the study preferring SRS for limited [≤4] BMs before vs. 61% preferring SRS after the publication, P < .001). The majority of respondents (88.2%) expressed a willingness to enroll patients on a recently opened recently opened randomized trial, NRG-CC009, comparing SRS versus hippocampal-avoidance WBRT. Conclusions: In the first survey of SRS for SCLC BMs, we observed a high level of physician openness to upfront SRS in SCLC, particularly for patients with limited numbers of BMs, as well as significant interest in generating prospective randomized data to clarify the role of SRS in this population.