Regression of multiple intracranial meningiomas after cessation of long-term synthetic progesterone (megestrol) medication: case report and autopsy

Abstract

We report the history of a woman who developed four intracranial meningiomas during 11 years of therapy with the synthetic progesterone agonist megestrol. After discontinuation of the drug at age 75 years, she improved clinically and a CT scan showed near complete regression of the meningiomas by 78 years. Autopsy was performed at 83 years of age following an accidental death. At the tumor sites, we found both collagenous tissue with small islands of low grade meningioma having strong nuclear immunoreactivity for progesterone receptor and lipomatous tissue. A literature review showed similar cases of radiologic meningioma regression following discontinuance of progestins. Our case is the first one with histopathologic characterization of the end point.

Keywords: Autopsy; Megestrol; Meningioma; Progesterone receptor; Tumor involution.

Figure 1

Figure 1. CT scans with contrast enhancement of brain showing dura-based tumors in the right parasellar, left frontal, and left parietal regions in a woman at ages 73.5 and 74.8 years when taking megestrol, and at ages 75.7 years and 82 years, after megestrol had been discontinued.

Figure 2

Figure 2. Line graph showing change in meningioma sizes on CT scans over time. Tumor size (in cm) is reported for the greatest dimension only. The arrow shows the time when megestrol was started and the vertical line shows the time when megestrol was discontinued.

Figure 3

Figure 3. a) Photograph showing the anterior cranial fossa with left frontal bone hyperostosis and yellowish thick, firm tissue (arrow) reflected from the anterior falx cerebri at the time of autopsy. b) Photograph showing the thickened dura mater near the superior sagittal sinus in the left parietal region after formalin fixation. c) Photomicrograph showing the left parietal dura and fibrotic tumor with lipomatous meningioma (arrow). Hematoxylin & eosin stain, original magnification 12.5x. d) Photomicrograph showing a cluster of meningothelial cells in the left frontal tumor. H&E stain, original magnification 200x. e) Photomicrograph showing the residual left parietal tumor with immunoreactivity for epithelial membrane antigen (EMA) in brown with blue hematoxylin counterstain. Original magnification 100x. f) Photomicrograph showing the residual left frontal tumor with nuclear immunoreactivity for progesterone receptor (PR) in brown. Original magnification 200x.