Overview of meningiomas: genetic basis, clinical evaluation, and therapeutic strategies

Abstract

Meningiomas are the most common primary intracranial tumor of the central nervous system. For the most part, they´re benign, appearing typically in adulthood and the female population. Meningiomas arise from meningothelial (arachnoid) cells, with tendency locate at the level of the skull´s base. The World Health Organization classification for meningiomas, commonly known as “WHO” classification, represents a fundamental tool for determining prognosis, recurrence rate, and decision-making, regarding the overall management of these patients. This classification is based on the histopathological characteristics of the tumor, classifying them into three grades; the greater the Grade, the fewer therapeutic options and less favorable outcome. A series of molecular profiles and genetic aberrations have been correlated with these degrees; allowing stratification based on cytogenetic findings. However, these profiles have yet to be considered in the latest update of the classification. Definitive diagnosis is based on histopathology, but initially magnetic resonance imaging (MRI) represents the study of choice for identification and follow-up of meningiomas.  The clinical presentation of meningiomas is often non-specific, and the physical exam tends to be unremarkable in most cases. Treatment for meningiomas is essentially determined by the meningiomas grade and is highly individualized. It includes a combination of observation, surgical resection, and radiotherapy (RT). Prognosis is predominantly determined by gross total resection and histopathology. The Simpson Grade System, correlates these elements in order to estimate the rate of recurrence after surgery. Advances in fields such as neuroimaging, radiology and neurosurgery; have allowed a higher degree of gross total resection to be achieved, improving the prognosis and survival rates of these patients. This review provides an overview of the genetic basis, general evaluation, and treatment for these tumors.