A 45-year-old woman is brought to the emergency department after an episode during which she abruptly lost consciousness and had rhythmic jerking movements of the limbs followed by a period of confusion. The patient has had mild daily headaches associated with nausea that have progressed over the past 2 years. The headaches are worse at night and occasionally awaken her. The patient reports no head trauma, visual changes, weakness, numbness, or difficulty swallowing or speaking. She does not use alcohol or illicit drugs. There is no family history of seizures. An intracranial mass is discovered on neuroimaging and a biopsy of the mass is shown in the image below. Which of the following is the most likely diagnosis?

Question

A 45-year-old woman is brought to the emergency department after an episode during which she abruptly lost consciousness and had rhythmic jerking movements of the limbs followed by a period of confusion.  The patient has had mild daily headaches associated with nausea that have progressed over the past 2 years.  The headaches are worse at night and occasionally awaken her.  The patient reports no head trauma, visual changes, weakness, numbness, or difficulty swallowing or speaking.  She does not use alcohol or illicit drugs.  There is no family history of seizures.  An intracranial mass is discovered on neuroimaging and a biopsy of the mass is shown in the image below.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

11ec160b_39ae_a255_9249_a306235ac214_MD0001_00 This patient's biopsy findings are consistent with meningioma, a slow-growing benign tumor derived from meningothelial cells of the arachnoid. Note the syncytial nests and whorled pattern of cellular growth, which may calcify and appear as round, laminar structures called psammoma bodies. Other examples of tumors that form psammoma bodies include papillary thyroid carcinoma, mesothelioma, and serous carcinoma of the ovary and endometrium. Meningiomas form well-circumscribed, round masses attached to the dura and are commonly found at the falcine, parasagittal, or lateral convexity regions of the brain. Seizure can occur due to compression of the adjacent cerebral cortex. Headaches, nausea, and vomiting may result from increased intracranial pressure, which worsens during recumbency and with sleep (due to increased intracranial blood volume). Individuals may also develop focal neurologic deficits depending on tumor size/location. (Choice A) Adamantinomatous craniopharyngiomas most often present as benign suprasellar tumors in children and appear as cords/nests of palisading squamous epithelium with areas of lamellar "wet" keratin under light microscopy. (Choice B) Ependymomas typically present as paraventricular tumors (eg, floor of the fourth ventricle) and have characteristic perivascular pseudorosettes under light microscopy. (Choice C) Glioblastomas are the most common primary malignant brain tumor in adults. They are often located in the cerebral hemispheres and may cross the corpus callosum ("butterfly glioma"). Light microscopy shows hypercellular areas of atypical astrocytes bordering regions of necrosis (pseudo-palisading). (Choice D) Medulloblastomas are malignant cerebellar tumors that typically occur in children and are characterized by small blue cells that may surround neuropil (ie, interwoven nerve fibers and synapses), forming Homer Wright rosettes under light microscopy. (Choice F) Oligodendrogliomas typically involve the white matter of the cerebral hemispheres, and tumor cells have a "fried egg" appearance (round nuclei surrounded by a halo of clear cytoplasm) under light microscopy. (Choice G) Pilocytic astrocytomas are usually benign tumors that involve the cerebellum in children and young adults. Light microscopy typically shows tumor cells with elongated hairlike processes, eosinophilic granular bodies, and Rosenthal fibers. (Choice H) Schwannomas are benign tumors that commonly arise from the vestibular branch of cranial nerve VIII at the cerebellopontine angle. Light microscopy typically shows spindle cells with palisading nuclei arranged around eosinophilic cores of fibrillary cell processes (Verocay bodies). Educational objective: Meningiomas are slow-growing, well-circumscribed, benign intracranial tumors typically found at the cerebral convexities in adults. Characteristic histopathologic features include syncytial nests and a whorled pattern of cellular growth, which may calcify into round, laminar structures called psammoma bodies.

A 45-Year-Old Woman Is Brought to the Emergency Department After