Efficacy of Intra-arterial [¹⁷⁷Lu]Lu-DOTATATE monotherapy for treatment-refractory meningioma

Purpose: For meningiomas that are refractory after local treatments, there are no systemic evidence-based therapeutic options to date. In recent years, somatostatin-targeted radionuclide therapy has emerged as a promising new treatment modality. Recent studies have indicated that intra-arterial administration of [¹⁷⁷Lu]Lu-DOTATATE may increase the tumor absorbed dose. This study aims to assess the efficacy of intra-arterial [¹⁷⁷Lu]Lu-DOTATATE in a cohort of treatment-refractory meningiomas. Materials and methods: Retrospective cohort study including patients diagnosed with treatment-refractory meningioma (WHO grade 1–3), who had received at least one cycle of intra-arterial [¹⁷⁷Lu]Lu-DOTATATE. Primary outcomes were progression-free survival (PFS) and overall survival (OS). Secondary outcomes included objective response, and safety and toxicity. Results: Seventeen patients with a median follow-up duration of 36 months (range: 1–57 months) were included. Six-month PFS was 65% (95% CI: 46–92%) and 6-month OS was 82% (95% CI: 66–100%). Regarding best objective response, disease control was found in 53% (95% CI: 28–77%); with an objective response rate of 24% (95% CI: 7–50%). In terms of safety, two patients developed grade 3 anemia, while one patient experienced local necrosis as a result of peripheral embolism, a complication related to angiographic intervention. Conclusion: In a treatment-refractory meningioma cohort, intra-arterial administration of [¹⁷⁷Lu]Lu-DOTATATE is safe and effective, with an objective response rate of 24%, and survival data that exceed published benchmarks. Prospective controlled studies with larger cohorts and extended follow-up are needed, comparing intra-arterial [¹⁷⁷Lu]Lu-DOTATATE to (historic) cohorts receiving intravenous administration are needed.