Recurrence benefit from supramarginal resection in brain metastases of lung adenocarcinoma

BACKGROUND: There is growing evidence that brain metastases (BM) have no well-defined boundaries and that conventional microsurgical circumferential dissection of BM is often inadequate to prevent local tumor recurrence. Previous studies have suggested that supramarginal resection can significantly improve local tumor control. We retrospectively analyzed the local tumor control in a series of patients with BM from lung adenocarcinoma. METHODS: We retrospectively analyzed 48 patients with BM for lung adenocarcinoma in Shenzhen Second People’s Hospital from May 2015 to May 2020. 26 resected lesions were located in eloquent areas and underwent standard gross total resection (GTR group); 22 resected lesions were located in ineloquent areas, after standard gross total resection, the periphery was expanded and resected by 5 mm (MTR group). The postoperative tumor recurrence was compared between the two groups. RESULTS: During the follow-up period, the local recurrence rates in the GTR group and the MTR group were 61.5% and 27.3% (p = 0.022), respectively. Within 6 months after surgery, the local recurrence rates in the GTR group and the MTR group were 42.3% and 13.6% (p = 0.029), respectively. Within 12 months after surgery, the local recurrence rates in the GTR group and the MTR group were 57.7% and 22.7% (p = 0.014), respectively. The median progression-free survival time after surgery was 7.0 months (95% CI 4.0–10.0 months) in the GTR group and 14.0 months (95% CI 11.4–16.6 months) in the MTR group (Log-Rank p = 0.008). Compared with the MTR group, the HR of local recurrence in the GTR group was 3.74 (95% CI 1.38–10.39, p = 0.010). Cox multivariable analysis showed no other factors associated with local recurrence except for the surgical method (p = 0.012). CONCLUSIONS: On the basis of conventional surgical total resection, expanded peripheral resection of 5 mm around the brain metastases of lung adenocarcinoma can significantly reduce the local recurrence rate and prolongs the progression-free survival time.