Prophylactic Cranial Irradiation for Limited-Stage Small-Cell Lung Cancer: Survey of US Radiation Oncologists on Current Practice Patterns

In this survey of 309 practicing US radiation oncologists, almost all respondents recommended prophylactic cranial irradiation (PCI) and pre-PCI brain magnetic resonance imaging (MRI)—practices endorsed by national guidelines. Only a third followed their patients with serial brain MRI after PCI, and about one third recommended memantine for patients undergoing PCI. This survey establishes a practice-pattern baseline for future clinical trials. Purpose: Prophylactic cranial irradiation (PCI) in patients with limited-stage small-cell lung cancer (LS-SCLC) is considered the standard of care. Meta-analysis of 7 clinical trials indicates a survival benefit to PCI, but all of these trials were conducted in the pre–magnetic resonance imaging (MRI) era. Therefore, routine brain imaging with MRI before PCI—as recommended by National Comprehensive Cancer Network guidelines—is not directly supported by the evidence. Current US practice patterns for patients with LS-SCLC are unknown. Materials and Methods: We surveyed practicing US radiation oncologists via an institutional review board–approved online questionnaire. Questions covered demographic information and treatment recommendations for LS-SCLC. Results: We received 309 responses from US radiation oncologists. Ninety-eight percent recommended PCI for patients with LS-SCLC, 96% obtained brain MRI before PCI, 33% obtained serial brain imaging with MRI after PCI to detect new metastases, and 35% recommended memantine for patients undergoing PCI. Recommending memantine was associated with fewer years of practice (P <.001), fewer lung cancer patients treated per year (P =.045), and fewer LS-SCLC patients treated per year (P =.024). Conclusion: Almost all responding radiation oncologists recommended PCI and pre-PCI brain MRI for LS-SCLC patients with disease responsive to initial therapy. Only a third of respondents followed these patients with serial brain MRI. Approximately one third provided memantine therapy to try to limit neurocognitive effects of PCI. Further research is warranted to determine the best treatment for patients with LS-SCLC. This survey can inform the development of future trials that depend on participation from radiation oncologists.