Retrospective study of 127 surgically treated patients with multiple brain metastases: indication, prognostic factors, and outcome

Abstract

Background: Metastases are the most frequent tumours in the brain. At the time of diagnosis, more than 50% of patients present with multiple lesions. The goal of our retrospective investigation was to evaluate the outcome of patients who undergo surgery for multiple cerebral metastases and to determine prognostic factors.

Methods: We included 127 patients with multiple brain metastases in the study. The median number of metastases was three. All patients were operated on for at least one lesion. The indications for surgery were: large tumours ≥27 cm(3), metastases of unknown primaries at the time of diagnosis, and space-occupying cerebellar lesions. If possible, adjuvant WBRT was applied.

Results: The median MST of the whole group was 6.5 months; for patients with complete resection, 10.6 months. According to the RPA classification the MST ranged between 19.4 (class I), 7.8 (class II), and 3.4 months (class III) (p < 0.001). KPS > 70 had a significant influence on MST (9.1 months vs. 3.4 months, p < 0.001), the number of lesions: 2-4 vs. >4 (p = 0.046), and postoperative WBRT in multivariate analysis (p = 0.026). Age was not a significant factor. The 2-year survival rate was 15% and the 3-year survival rate 10%.

Conclusions: Favourable factors for prolonged survival were complete resection of all lesions, no more than four metastases, RPA-class I and adjuvant WBRT. The resection of large lesions, while leaving smaller residual ones, did not result in increased survival.