2023 American Academy of Neurology Abstract Website

Objective:

To study the neurological presentation and outcomes of patients with motor cortex brain metastases treated with stereotactic radiosurgery (SRS).

Background:

Literature on the neuro-oncological impact of radiosurgery in eloquent brain regions with regards to safety, efficacy, and survival is limited.

Design/Methods:

We used our prospective patient registry to obtain data imaging and clinical outcomes. Additional volumetric measurements were made from imaging data.

Results:

279 motor cortex metastases with volumes from 0.01 cm³ to 12.18 cm³ (mean 0.74 cm³) in 208 patients treated with SRS between 2012 and 2021 were analyzed. Margin dose varied from 10 Gy to 20 Gy (mean 16.9 Gy). Control rate after SRS was 97.8%. Perilesional edema was seen in up to 25% of tumors at presentation. After SRS, adverse radiation effects (ARE) were noted in 6% of all tumors, symptomatic in 1.4%. Median time to symptomatic ARE was 8 months. All patients with ARE exhibited edema post treatment. Edema without ARE was seen in an additional 13%. New focal seizures were seen in 5 patients (2%), and new generalized seizures in 1 (0.3%). Thirty-six patients (17%) presented with motor deficits. At final follow up, 85% were improved or unchanged – 13 (41%) had a normal exam, 10 (31%) had mild deficits, and 9 (28%) still had moderate deficits. New brain metastases were found in 31% of patients at a median of 8 months. KPS improved following SRS in 24%. Median survival after radiosurgery was 10 months. Absence of neurological deficit, RPA Class I and II, and margin dose > 18 Gy were each associated with a significant survival advantage on univariate analysis.

Conclusions:

SRS for motor cortex brain metastases is safe and effective in providing tumor control. Patients identified with tumors before onset of neurological deficits have better outcomes. Treated patients show improvement in neurological deficits and performance scores.