Impact of tumor size and peritumoral edema on outcomes and complications in anterior midline skull base meningiomas.

Introduction: Surgical resection is the primary treatment for symptomatic anterior midline skull base meningiomas. Research question: This study evaluates the impact of tumor size and peritumoral edema on clinical outcome. Material and methods: A retrospective analysis of 109 patients who underwent resection between 2012 and 2022 was conducted. Tumors were categorized as: size 1 (<30 mm), size 2 (30-50 mm), and size 3 (>50 mm). Peritumoral edema was classified as: type 1 (no edema), type 2 (edema diameter < tumor diameter), and type 3 (edema diameter > tumor diameter). Clinical outcomes were assessed using the Karnofsky Performance Scale (KPS) at discharge, three months postoperatively, and at last follow-up. Additionally, complication rates were analyzed. Results: Patients with size 3 tumors had significantly worse KPS scores at discharge (50 %) than those with size 2 (70 %) or size 1 tumors (80 %; p < 0.0001). At three months, KPS differences remained significant (p = 0.0209). For size 3 tumors, KPS at discharge was significantly associated with edema: 90 % for no edema, 70 % for type 2 edema, and 50 % for type 3 edema (p = 0.0008). Complication rates were higher in size 2 and 3 tumors (35-37 %) compared to size 1 (14 %; p = 0.0330). Tumors with peritumoral edema had increased complication rates (35 %) versus those without (23 %; p = 0.2051). Discussion and conclusions: The combination of large tumor size and extensive peritumoral edema are associated with reduced early postoperative outcomes and higher complication rates. These findings underscore the importance of careful preoperative patient selection and tailored surgical strategies to optimize patient outcomes.