Objectives Evaluate the outcomes of differing management strategies for incidental intracranial meningiomas.

Design Systematic review.

Subjects Studies with ≥10 patients≥16 years of age diagnosed radiologically with an incidental intracranial meningioma.

Methods PRISMA compliant methods were used to scan 6 databases up to September 2017. PROSPERO ID: CRD42017077928.

Results Twenty retrospective studies (n=2130 patients) were included. Initial management strategies at diagnosis were: 27% (n=560) surgery, 22% (n=450) SRS and 51% (n=1040) active monitroing with a mean follow-up of 49.5 months (SD=29.3). 21% (n=220) of patients in the active monitoring cohort eventually had or were recommended an intervention due to: radiological progression (n=153), development of symptoms (n=66) and patient preference (n=1). Mean time-to-intervention was 24.8 months (SD=18.2). 94% (n=207) of interventions were within 5 years. The definition of ‘growth’ and the radiological surveillance regimens varied widely. Morbidity rates following surgery and SRS, accounting for cross over, were 15% and 22% respectively. Surgery revealed benign histology in 94% of the cases. Quality of life is improperly examined.

Conclusions The management of patients with incidental intracranial meningiomas varies widely. Most patients who develop clinical or radiological progression will do so within 5 years of diagnosis. Intervention at diagnosis may result in unnecessary overtreatment. Prospective data is needed to develop a risk calculator for managing incidental meningioma.