Long-term recurrence risk after resection of intracranial meningiomas: cohort study with up to 15 years of follow-up

Although most meningiomas are benign, recurrence remains a clinical concern, particularly in cases of subtotal resection (STR) where complete tumor removal is not feasible due to involvement of critical structures, Adjuvant gamma knife radiosurgery (GKRS) is often considered in these patients; yet the long-term effectiveness of GKRS is not well characterized. A retrospective cohort study at two centers of Sichuan University (Chengdu, China) included 949 adult patients who underwent surgical resection for intracranial meningiomas between 2009 and 2017, with follow-up through 2024. The primary outcome was recurrence-free survival (RFS). The 15-year RFS rate was 79.2% (95% CI 74.2-84.6). In STR cases, a second recurrence peak emerged at 7 to 10 years. GKRS was associated with lower recurrence risk (HR 0.50; 95% CI 0.27-0.90), especially in convexity tumors. Ki-67 > 5% and progesterone receptor negativity showed nonsignificant trends toward higher recurrence risk. The authors conclude that adjuvant GKRS showed long-term benefit after resection of intracranial meningioma.