Surgically treated brain metastases of gastric origin: a case series and systematic review.

Background: The incidence of brain metastases from gastric origin is less than 1% in those with primary gastric cancer. Given this exceedingly rare presentation, there is limited literature describing the outcomes of their neurosurgical treatment. We wish to identify the role of surgical intervention for brain lesions in metastatic gastric cancer via institutional case series and systematic review.

Methods: This study was divided into two sections: (1) a retrospective, single-center patient series assessing outcomes of neurosurgical treatment modalities in patients with malignancy arising from the stomach with brain metastases and (2) a systematic review abiding by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines between the years of 1980 and 2021 assessing outcomes of patients with primary stomach cancer with metastasis to the brain treated with surgery.

Results: Four patients with gastric brain metastases were treated at our institution, and 16 patients were identified in literature from a total of 9 studies and case reports. The mean age at the time of stomach cancer diagnosis was 57.3 years, with a mean time to brain metastases of 14.8 months. The primary gastric cancer was most commonly adenocarcinoma (70%). Patients most presented with single lesions (58%) and were treated with multimodal neurosurgical intervention (65%). Mean overall survival following neurosurgery was 12.45 months.

Conclusion: Brain metastases from gastric origin are extremely rare. Surgical resection of metastatic brain lesions should be considered as a treatment modality in surgical candidates. Future attention should be given to the effect of adjuvant therapies and surgical techniques on survival and quality of life.