Houdini Tumor: Case Report and Literature Review of Pregnancy-Associated Meningioma

Background: Meningiomas are common intracranial neoplasms of undetermined etiology. Accelerated growth during episodes of elevated serum estrogen and progesterone have been demonstrated in pregnant patients, as exhibited by an overexpression of estrogen or progesterone on immunohistochemical analysis. This case report and literature review describe a case of complete meningioma regression in a postpartum patient. Case Description: A 23-year-old female presented at 37 weeks of pregnancy with 1-month history of fluctuating severe left-sided headaches, periodic blurry vision, nausea, and vomiting. She had 2 previous pregnancies without complication. Magnetic resonance imaging revealed a dural-based, heterogeneously enhancing mass along the left tentorium, just posterior to the transverse sinus, with supratentorial extension and surrounding edema. Differential diagnoses included meningioma versus hemangioma versus hemangiopericytoma. The patient followed up with neurosurgery 1 month after delivery. She had continued left-sided headaches but no longer complained of visual changes. A postpartum surgical resection via left occipital and suboccipital craniotomy was planned. Approximately 1 month later (now about 3 months after delivery) a repeat magnetic resonance imaging demonstrated a marked decrease in meningioma size, and the previously seen edema had resolved. In light of the sudden disappearance of the meningioma, no further surgical intervention was pursued. Conclusions: Because meningioma shrinkage or disappearance may occur after pregnancy, repeat imaging is advised as part of a preoperative evaluation. In addition, it is possible that an undetermined amount of meningioma removal surgeries may be avoided with further research into monitoring hormone levels connected to meningioma growth.