Meningiomas and the Polynesian population

In Auckland Hospital, New Zealand there has been a perception for many years that the incidence of meningiomas was higher in Polynesians. It was also suspected these occurred at a younger age in Polynesians and were more likely to be multiple. The purpose of the present study was to confirm whether the Polynesian population does have a higher incidence of meningioma, review at what age they presented with meningioma and compare the outcome of treatment with Caucasians.

A retrospective review was performed of 302 patients who had had a cranial meningioma excised in the 10 years between 1991 and 2001 at Auckland hospital. Age, sex, ethnicity, number of tumours, type, size, comorbidities, time to presentation and outcome at discharge and follow-up were recorded.

Polynesians had a significantly higher incidence of meningiomas (P < 0.0001). In particular Polynesian women were significantly over represented. (P < 0.05). Polynesians were more likely to have two or more tumours (P < 0.02) and they presented at a significantly younger age (P < 0.0001). The tumours were also larger. (P = 0.0006). Despite this Polynesians did not have a worse outcome at discharge or at follow up (P > 0.1) nor did they have a higher incidence of comorbidites, perhaps reflected by their younger age.

There is a higher incidence of meningiomas in the Polynesian population, particularly young Polynesian women. The tumours are more likely to be multiple and larger in Polynesians. The present study confirms a predisposition to meningioma in New Zealand Polynesians and should lead to further investigation into whether this is genetic (likely chromosome 22) or hormonal possibly mediated by insulin-like growth factor-1.