Hunting for the causes of meningioma--obesity is a suspect.

In this issue of the journal, Michaud and colleagues report a 48% increased risk of meningioma in obese individuals compared with individuals with a normal body mass index (BMI). This large prospective cohort study adds weight to the suggested link between BMI and meningioma, thus contributing to the growing number of cancer sites likely associated with body fatness. Although the exact mechanisms underlying the BMI-meningioma link are unclear, possible mediators include hormonal factors, immunologic response, and levels of insulin or insulin-like growth factors, each of which has been implicated by various levels of evidence in meningioma risk. Understanding the relationships between body fatness, height, and hormonal and immunologic factors could provide important clues to the etiology of meningioma and may have implications for the early detection and prevention of these tumors.