Surgical Treatment of Cerebellar Metastases: Survival Benefits, Complications and Timing Issues

SIMPLE SUMMARY: Cerebellar metastases are often considered to have a poor prognosis. This retrospective study investigated the clinical course and functional outcome of 73 patients who underwent surgical treatment for cerebellar metastases. Median overall survival was 9.2 months which compares favorably with the more recent literature. Prognosis varied strikingly between individuals. This suggests a policy of individualized decision-making which includes offering surgery also in selected cases with adverse prognostic parameters. The presence of extracerebral metastases did not significantly influence survival which may justify expedited surgery in selected cases prior to the oncological work-up. Systemic therapy was associated with substantially better survival indicating that recent advances in medical oncology might amplify any survival benefit derived from surgery. Surgery was found to carry significant morbidity and even mortality. Major complications often precluded adjuvant treatment and correlated with markedly reduced survival. Complication avoidance is therefore of utmost importance. ABSTRACT: We retrospectively studied 73 consecutive patients who underwent surgery 2015–2020 for removal of cerebellar metastases (CM). Median overall survival (medOS) varied widely between patients and compared favorably with the more recent literature (9.2, 25–75% IQR: 3.2–21.7 months vs. 5–8 months). Prognostic factors included clinical (but not radiological) hydrocephalus (medOS 11.3 vs. 5.2 months, p = 0.0374). Of note, a third of the patients with a KPI <70% or multiple metastases survived >12 months. Chemotherapy played a prominent prognostic role (medOS 15.5 vs. 2.3, p < 0.0001) possibly reflecting advances in treating systemic vis-à-vis controlled CNS disease. Major neurological (≥30 days), surgical and medical complications (CTCAE III–V) were observed in 8.2%, 13.7%, and 9.6%, respectively. The occurrence of a major complication markedly reduced survival (10.7 vs. 2.5 months, p = 0.020). The presence of extracerebral metastases did not significantly influence OS. Postponing staging was not associated with more complications or shorter survival. Together these data argue for individualized decision making which includes offering surgery in selected cases with a presumably adverse prognosis and also occasional urgent operations in cases without a preoperative oncological work-up. Complication avoidance is of utmost importance.