Meningeal Hemangiopericytoma Presenting as Pure Gerstmann Syndrome: A Double Rarity.

Gerstmann syndrome is a neurobehavioral syndrome characterized by four cardinal symptoms: acalculia, agraphia, finger-toe agnosia, and dysgraphia. The syndrome is caused primarily by lesions at the confluence of parietal, temporal, and occipital lobes, but also can involve the middle frontal lobe of the dominant hemisphere. Documented inciting lesions include stroke, tumor, hemorrhage, arteriovenous malformations, and seizures. A meningeal solitary fibrous tumor (SFT)/hemangiopericytoma (HPC) is a diagnostic challenge due to its resemblance to more common brain tumors like meningioma, with histopathology being the definitive diagnostic test. A 37-year-old male presented to our tertiary center with blurred vision, "not being himself," and "acting funny" for three weeks. On exam, he was found to have a right inferior quadrantanopia, grade II papilledema and demonstrated all four symptoms of Gerstmann syndrome - inability to perform simple calculations (acalculia), or identify his fingers (finger agnosia), could not distinguish his left side from the right (left-right disorientation), nor write out his name (agraphia). Brain imaging showed an extra-axial, highly vascularized 7.6-cm mass compressing the left parietal lobe. He underwent a complete resection of the mass. Postoperatively, he had gradual improvement with complete resolution of agraphia, acalculia, finger agnosia, and left-right disorientation within a week status post-resection. Tumor pathology indicated hemangiopericytoma/solitary fibrous tumor. This case enunciates the enigmatic tetrad of Gerstmann syndrome. Though classically described as a sequela of stroke, the mass effect of the tumor on the parietal lobe may produce the symptoms, which can resolve following resection.

Pleomorphic xanthoastrocytoma: a brief review.

Pleomorphic xanthoastrocytoma (PXA) is a rare primary CNS tumor. Recent advances in the molecular characterization are helping to define subtypes of tumor. The discovery of BRAF mutations within a substantial percentage of PXA fosters a clearer understanding of the pathophysiology of these tumors with clear prognostic and therapeutic implications. These findings are expected to provide insight into the spectrum of clinical behavior observed in PXA, ranging from cure with surgery to diffuse dissemination throughout the neuraxis. This review details the clinical presentation including radiographic appearance of PXA. Pathology, including molecular pathology is discussed. Therapeutic management including surgical resection, radiotherapy and systemic therapies are reviewed.

B cell-rich non-neoplastic sentinel lesion preceding primary central nervous system lymphoma.

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is an uncommon tumor in the brain. Although most PCNSL are readily diagnosed as diffuse large B cell lymphoma (DLBCL) on the first biopsy, very rare cases have been described in which the first detected intracerebral lesions are non-neoplastic, and are composed mostly of perivascular T cells, not B cells. This phenomenon is known as "sentinel lesions."

Recent advances in managing/understanding meningioma.

Meningiomas are the most common adult primary intracranial tumor. Despite their higher incidence, there have not-until recently-been as many advances in understanding and managing meningiomas. Thus far, two broad classes of meningiomas have emerged on the basis of their mutational profile: those driven by neurofibromatosis 2 (NF2) inactivation and those with non-NF2 driver gene alterations, such as mammalian target of rapamycin and Hedgehog, Wingless/b-catenin, Notch, transforming growth factor-b receptor, mitogen-activated protein kinase, and phospholipase C pathway alterations. In addition to improvements in molecular diagnostics, advances in imaging are being studied to better predict tumor behavior, stratify risk, and potentially monitor for disease response. Management consists primarily of surgery and radiation therapy and there has been limited success from medical therapies, although novel targeted agents are now in clinical trials. Advances in imaging and understanding of the genetic makeup of meningiomas demonstrate the huge potential in revolutionizing the classification, diagnosis, management, and prognosis of meningiomas..