Multiple meningiomas arising during long-term therapy with the progesterone agonist megestrol acetate. Case report.

In this report the authors describe a woman with low-grade endometrial stromal sarcoma who was treated with total abdominal hysterectomy and bilateral salpingo-oophorectomy. After receiving megestrol acetate continuously for 19 years for chronic hormone suppression, she began to experience progressive dementia. Magnetic resonance imaging revealed 11 separate intracranial meningiomas of various sizes. The largest lesions were treated with staged angiographically guided embolization and excision. Despite discontinuation of megestrol acetate, the remaining smaller lesions grew slightly in size, requiring further treatment with a combination of excision and gamma knife stereotactic surgery. All of the excised tumors showed positive staining for progesterone receptors on immunohistochemical examination. Prolonged therapy with megestrol acetate could promote the growth of benign intracranial meningiomas in some patients.