Pathophysiology of Meningioma Growth in Pregnancy.

Meningioma is among the most frequent brain tumours predominantly affecting elderly women. Epidemiological studies have shown that at the age of fertility the incidence is relatively low. The biological behaviour of meningioma in pregnancy is different from other meningiomas. The possible explanation is rooted in the complex physiological changes and hormonal differences during pregnancy. The increased meningioma growth observed in pregnancy is presumably the result of endocrine mechanisms. These include increase in progesterone, human placental lactogen (hPL) and prolactin (PRL) serum levels. In contrast, levels of pituitary hormones such as follicle stimulating hormone (FSH), luteinizing hormone (LH) and human chorionic gonadotropin (hCG) produced by the placenta are decreasing in the mother prior to childbirth. Besides, vascular factors also play a crucial role. Peritumoral brain edema (PTBE), with well-known causative association with vascular endothelial growth factor (VEGF), can often be seen both with imaging and in the surgical specimens. Our aim is to assess published research on this topic including diagnostic and therapeutic guidelines, and to provide a clinically useful overview on the pathophysiology and biological behaviour of this rare complication of pregnancy.