Meningioma regression following depot medroxyprogesterone acetate withdrawal: a case series.

Background: Progesterone signalling is a key determinant of meningioma behaviour, particularly in skull base tumours. Cyproterone acetate-associated meningiomas stabilise or regress after withdrawal Whether similar reversibility follows cessation of depot medroxyprogesterone acetate (DMPA), a widely used long-acting injectable contraceptive, is poorly characterised. Methods: Retrospective case series of three women with intracranial meningiomas who discontinued DMPA following neurosurgical assessment, assessed with post-contrast CT (Cases 1 and 2) or magnetic resonance imaging (Case 3). Results: All had prolonged DMPA exposure (approximately 14-27 years) and predominantly skull base disease with WHO grade I meningothelial histology. Each demonstrated measurable regression of enhancing soft-tissue tumour after cessation, despite marked heterogeneity in disease burden and chronicity, including one patient with multifocal meningiomatosis and more than a decade of documented progression. Hyperostotic bone showed no regression, and two patients required optic nerve and orbital decompression for progressive visual loss despite soft-tissue regression. Conclusion: DMPA-associated meningiomas can regress following drug withdrawal, but the response is confined to the soft-tissue component. Persistent hyperostosis may continue to cause compression, and withdrawal should not be assumed to remove the need for surgery. These findings support routine assessment of progestin exposure in patients with meningioma.