# Evaluating the Impact of Index Metastasis Resection in Patients with Multiple Brain Metastases

## TL;DR

This study examines whether removing a main brain metastasis and treating others with radiation improves survival and function in patients with multiple brain metastases.

## Contribution

The study provides clinical evidence that complete resection of a symptomatic brain metastasis may reduce seizure risk and improve functional outcomes.

## Key findings

- Complete resection of the index lesion was associated with fewer postoperative seizures.
- Radiation of residual lesions was important for prognosis, though survival differences were not significant.
- Aggressive local therapy may offer functional benefits in selected patients with multiple brain metastases.

## Abstract

This retrospective study evaluated patients with single, oligometastatic, and multiple brain metastases who underwent surgical removal of a symptomatic “index” lesion followed by radiotherapy of the remaining metastases. The aim was to assess whether this combined approach improves survival and functional outcomes. The median survival did not differ significantly between groups, but patients with complete resection of the index lesion experienced fewer postoperative seizures. These findings suggest that while surgery plus radiotherapy may not extend survival in all patients with multiple brain metastases, carefully selected individuals can still achieve meaningful functional benefits. Clinically, this highlights the potential role of aggressive local therapy in selected patients, expanding options beyond purely palliative strategies.

Background: The impact of surgical resection on the survival and functional outcomes of patients with multiple brain metastases remains a critical question in neuro-oncology. Methods: This retrospective study involved 160 patients who underwent surgical resection of brain metastases from 2017 to 2020. Patients were classified by the number of metastases—single, oligometastatic, or multiple—and whether complete removal of the main symptomatic lesion was achieved. Outcomes such as survival rates, complications, and functional status were assessed. Results: Among the patients, 48.1% had a single metastasis, 21.9% were oligometastatic, and 30% had multiple metastases. Survival did not differ by number of metastases when the main lesion was completely resected and remaining lesions were radiated (p = 0.6172). Complete resection increased mean survival to 15.74 months compared with 4.5 months without it. Additionally, patients who underwent complete resection experienced fewer seizures (16.2% vs. 32.6%, p = 0.019), implying a lower seizure risk. Functional independence was maintained post-surgery. Conclusions: While multiple brain metastases are generally associated with poor outcomes, a trend toward longer survival was observed after complete resection of the index metastasis, though this was not statistically significant. Radiation of residual lesions remains important to support prognosis. Reducing the tumor volume is key to lowering seizure risk. This study supports the role of aggressive surgical interventions, paired with radiation, to potentially enhance outcomes in patients with multiple brain metastases.