SURG-45. OUTCOMES OF PATIENTS RECEIVING SURGICAL RESECTION AND STEREOTACTIC RADIOSURGERY VS. STEREOTACTIC RADIOSURGERY ALONE FOR MOTOR CORTEX METASTASES

Abstract BACKGROUND Local therapy for brain metastases typically involves stereotactic radiosurgery (SRS), with surgical resection considered for larger and/or symptomatic tumors. For lesions in eloquent areas, surgical management is controversial given the risks of neurologic deficits. This study compared clinical outcomes in patients with motor cortex metastases who received surgery + SRS or SRS alone. METHODS Patients treated for motor cortex metastases from 1/2018 – 12/2022 were identified. Demographic/preoperative variables included age, gender, race, tumor histology, adjuvant therapies, pre-treatment neurological exam, and Karnofsky Performance Scale. Treatment variables included the number of brain metastases, maximum tumor diameter, and radiation dose/number of fractions. Outcome measures included post-treatment neurological exam, seizures, and overall survival (OS). RESULTS 351 charts were identified – 80 surgery + SRS and 271 SRS alone. 50 consecutive patients in each group were included in this analysis. Surgery + SRS patients were younger (59.0 vs. 63.9; P=0.020) with larger tumors (2.8 vs. 0.83cm; P<0.001), while the SRS only group had more brain metastases per patient (2 vs. 6; P<0.001). No differences were seen in the remaining demographic/preoperative variables. Pre-treatment, surgery + SRS patients had significantly increased frequency (45/50, 90% vs. 25/50, 50%; P<0.001) and severity (4 vs. 5; P=0.001) of motor deficits, and a higher likelihood of seizures (25/50, 50% vs. 8/50, 16%; P<0.001). Despite the surgery + SRS group being more symptomatic pre-treatment, the frequency and severity of motor deficits and seizures was similar between cohort’s post-therapy. Surgery + SRS patients also demonstrated higher rates of pre- to post-treatment improvement in motor function (29/45, 64% vs. 3/25, 12%; P<0.001) and longer OS from the date of treatment (7.5 vs 4 months; P=0.021). CONCLUSION Given the equivalent neurological outcomes, higher rates of functional improvement, and improved oncologic outcomes, surgery should be a consideration for patients with brain metastases in eloquent areas, particularly those with symptomatic lesions.