Fig 3.

Histopathologic sections from the anterior and posterior lobes corresponding to regions of interest 1 and 2, respectively.

A, Anterior biopsy shows hyperchromatic tumor cells arranged in sheets consistent for a typical meningioma (hematoxylin-eosin, magnification ×200).

B, Posterior biopsy demonstrates pleomorphic tumor cells arranged in attenuated clusters with pseudoglandular formation. This is histologically identical to the patient’s prior breast carcinoma (hematoxylin-eosin, magnification ×200).

C, Section through the resected tumor reveals the interface between the typical meningioma and metastatic breast carcinoma (hematoxylin-eosin, magnification ×40).