Stereotactic radiosurgery versus whole-brain radiotherapy after resection of solitary brain metastasis: A systematic review and meta-analysis.

Objective: The standard of care in patients with solitary brain metastasis involves surgical resection and postoperative whole-brain radiotherapy (WBRT). However, WBRT is associated with adverse effects, mainly neurocognitive deterioration. Stereotactic radiosurgery (SRS) is a more targeted form of radiation therapy that could be as effective as WBRT without the detrimental neurocognitive decline. Methods: We performed the first systematic review and meta-analysis comparing postoperative SRS versus postoperative WBRT in patients with one resected brain metastasis. PubMed, Scopus, and Cochrane library were systematically searched for studies comparing the efficacy of the two radiation modalities in terms of local and distant brain control, leptomeningeal disease control, and overall survival. Additionally, we extracted patients' neurocognitive function and quality of life after each postoperative radiation form. Results: Four studies with 248 patients (128: WBRT, 120: SRS) were included in our analysis. There was no difference between SRS and WBRT in the risk of local recurrence (RR = 0.92, CI = 0.51-1.66, p = 0.78, I2 = 0%) and leptomeningeal disease (RR = 1.21, CI = 0.49-2.98, p = 0.67, I2 = 18%), neither in the patients' overall survival (HR = 1.06, CI = 0.61-1.85, p = 0.83, I2 = 63%). Nevertheless, SRS appeared to increase the risk of distant brain failure (RR = 2.03, CI = 0.94-4.40, p = 0.07, I2 = 61%). Neurocognitive function and quality of life in the SRS group were equal or superior to the WBRT group. Conclusions: Although SRS may increase the risk of distant brain failure, it appears to be as effective as WBRT in terms of local control, risk of leptomeningeal disease, and overall survival while sparing the patients of the detrimental, WBRT-associated cognitive deterioration.