Intracranial Myopericytoma/Myofibroma (Haemangioperycitoma) in Pediatric Patient: an Exclusive Case Report with Differential Diagnosis in Meningoangiomatosis and DNET

Case Report: A 13-year-old girl with no known illnesses suffered a four generalized seizure 10 months prior to performed a surgery on the brain. After 6 months that the girl suffered generalized seizures she beguns partial seizures in the upper right member. Treatment was begun with antiseizure medications after 1 month of seizures with phenytoin 100 mg three times per day. The MRI report was suggestive of lesions with neuroglial origin, being DNET (neuroepithelial dysemblioplastic tumor) and Ganglioglioma or Gangliocitoma the most probable. A left frontal craniotomy was performed and the soft tumor resected. The tumor was intraaxial with no involvement of the overlying dura or falx. Primarily, histopathology showed a highly cellular and vascularized lesion fragment composed of epithelioid and spindle cells with discrete atypia. All these findings suggest the diagnosis of cerebral meningioangiomatosis (MA). There was diagnostic doubt and the material was sent to University of California, San Francisco, USA. The morphologic and immunohistochemical features support the diagnosis of a spindle cell neoplasm within the meninges. We favor a perivascular type of myogenic tumor such as myofibroma or myopericytoma, given the cytology and strong SMA positivity.

Discussion: Myopericytoma is a rare tumor, derived from perivascular myoid cells, which mainly affects soft tissues. With few reports of its occurrence in the central nervous system, its origin, morphology and physiopathological behavior are current challenges for neurosurgery and neuropathology. One of their descriptions by Granter et al. In 1998 reports that this tumor is part of a spectrum of tumors with perivascular myocyte differentiation including myofibromas, glomangiopericytomas and angioleiomyomas. Although some characteristics of the tumor point to the diagnosis of meningioangiomatosis, the immunohistochemical study defines the lesion as a spectrum that includes the possibility of a myofibroma or myopericytoma, suggesting clinical follow-up of the patient.

Conclusion: We present the description of an intracranial myofibroma/myopericytoma (hemangiopericytoma) in the pediatric range. This case also showed the extreme importance of a detailed histopathological and immunohistochemical study for the diagnostic approach, since the macroscopic and radiological aspects of the lesion can lead to a range of differential diagnosis.