The incidence trends of primary brain tumors in Saskatchewan from 1970 to 2001

There has been a paucity of information on the epidemiology of primary brain tumors (BTs) in Canada. This study documents epidemiology of primary BTs in Saskatchewan over three decades to define their current state, changing pattern over years and relative distribution in two geographically defined areas of the province.

Data on all primary BTs from 1970 to 2001 from the Brain Tumor Registry in Saskatchewan was collected. The aggregate data on primary BTs including the time-series for incidence, age, geographic location and sex were statistically analyzed using SPSS 13. Poisson regression was used to model the incidence as a function of decade of diagnosis and age at the time of diagnosis.

The average annual incidence of primary BTs was 11.1 per 100,000 person-years (male 12.5 per 100.000 and female 9.8 per 100.000). Males constituted 54.5% of all these tumors. The age distribution of tumors was bimodal with peaks at 5 years and 65 years. During this time, the incidence of primary BTs has increase predominantly in non-malignant types. No difference was found in the rate of all the diagnosed primary BTs combined, meningioma and lymphoma between the northern part (Regina) and southern part (Saskatoon) of the province.

The incidence of BTs in Saskatchewan is more than previously reported in Canada. There is a temporal trend in increasing incidence of some of the BTs predominantly in the non-malignant types. No spatial difference in the incidence of primary BTs was shown in this province. These data will provide useful information to guide the future studies on BTs changing patterns, possible etiologies and efficient resource allocation for management of these diseases.