Incidence trends of adult primary intracerebral tumors in four Nordic countries

Abstract

Brain tumors are some of the most lethal adult cancers and there is a concern that the incidence is increasing. It has been suggested that the reported increased incidence can be explained by improvements in diagnostic procedures, although this has not been totally resolved. The aim of our study was to describe the incidence trends of adult primary intracerebral tumors in four Nordic countries during a period with introduction of new diagnostic procedures and increasing prevalence of mobile phone users. Information about benign and malignant primary intracerebral tumor cases 20 -79 years of age was obtained from the national cancer registries in Denmark, Finland, Norway and Sweden for the years 1969 -98 and estimates of person-years at risk were calculated from the information obtained from national population registries. Annual age standardized incidence rates per 100,000 person-years were calculated and time trends analyses were carried out using Poisson regression. The overall incidence of all intracerebral tumors ranged from 8.4 -11.8 for men and 5.8 -9.3 for women, corresponding to an average annual increase of 0.6% for men (95% confidence interval [CI] ‫؍‬ 0.4, 0.7) and 0.9% for women (95% CI ‫؍‬ 0.7, 1.0). The increase in the incidence was confined to the late 1970s and early 1980s and coinciding with introduction of improved diagnostic methods. This increase was largely confined to the oldest age group. After 1983 and during the period with increasing prevalence of mobile phone users, the incidence has remained relatively stable for both men and women.

Historical distribution of central nervous system tumors in the Mexican National Institute of Neurology and Neurosurgery

“…44,45 In general, CNS tumors were most often noted in women, a finding that has also been reported by other groups. 46,47 The predominance of germ cell and neuroepithelial tissue tumors in men and meningeal tumors in women agrees with results that have been previously reported. 48,49 This gender predominance could be attributed to sex hormones and genetic differences between men and women.…”

Glioma Risk in Relation to Serum Levels of Insulin-Like Growth Factors

“…The observed number of cases in the study population is approximately the number we expected based on reported incidence in the Nordic countries (24). Blood samples were taken a minimum of 5 years before cancer diagnosis, lessening but not precluding the likelihood that IGF levels were influenced by the tumor.…”

Reproductive Factors and Risk of Meningioma and Glioma

“…An association between breast cancer and meningioma has been reported, with an elevated risk of meningioma among women with a previous diagnosis of breast cancer and an elevated risk of breast cancer among women with a previous diagnosis of meningioma (3,4), suggesting common genetic or environmental risk factors. The incidence of glioma is, in contrast, f1.5 times greater in men than women (2,5). The higher incidence in men becomes evident around the age of female menarche, reaching a maximum around the age of menopause and diminishing thereafter (6).…”