Investigating local recurrence in secondary brain tumours

Abstract AIMS Brain metastases result in considerable morbidity and mortality. Modern treatment strategies are increasingly omitting radiation therapy after surgical resection of these tumours. We investigated the rate of local recurrence in patients who had undergone surgery for brain metastasis in a single-institution study and compared it to the literature through a comprehensive meta-analysis. METHOD Patients undergoing surgery for a brain metastasis were identified and their records reviewed. Data on treatment and outcome was extracted and analysed. A systematic-review and meta-analysis, registered in PROSPERO (CRD42023391637), was conducted following the PRISMA statement. RESULTS The single-institution study comprised 358 cases, 40% (n=142) male and 60% (n=216) being female with a median age at surgery of 60 years (range 23-85 years). The most frequent primary cancer was lung cancer affecting 35% (n=126), followed by breast cancer (24%, n=87) and malignant melanoma (13%, n=47). Among the cases 142 underwent surgery without any adjuvant radiation. The median freedom from local recurrence at 12-months for this population was 38.3% (95% CI 13.4, 44.6). The meta-analysis encompassed three studies, with a total of 170 cases. Freedom from local recurrence at 12-months was found to be 42.4% (95% CI 34.9 - 50.1) following surgery alone. CONCLUSIONS We define for the first time the rates of local recurrence following surgery alone for brain metastases with a large single-centre series and a meta-analysis. As radiation is increasingly being omitted in these cases, caution should be exercised, and more investigation of the factors associated with local recurrence after surgery and how they be modified are required.