Neoplasms of the central nervous system in Norway. II. Descriptive epidemiology of intracranial neoplasms 1955-1984.

A population-based study of 8480 patients - 4508 (53%) males and 3972 females - with primary intracranial neoplasms reported to the Norwegian Cancer Registry during the period 1955-84, is presented. 81% of the cases were histologically verified. The peak age-specific incidence rate in the total series occurred in the age-group 55-64 years. Gliomas constituted the largest histological group with an age-adjusted incidence rate of 5.0 cases per 100,000 population per year for males and 3.5 for females. Case ascertainment of primary intracranial neoplasms is reduced above the age of 60 in Norway, mostly due to a a low autopsy rate. The major impact of the introduction of computer tomography (CT) in the case ascertainment of intracranial neoplasms has been a raised incidence, in patients over the age of 60, of neoplasms which are not histologically verified.