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Background: We present a national surveillance report on malignant primary brain and other central nervous system (CNS) tumors diagnosed in the Canadian population in 2009-2013., Methods: Patients were identified through the Canadian Cancer Registry, an administrative dataset that includes cancer incidence data from all provinces/territories in Canada. Tumor types were classified by site and histology using the definitions from the Central Brain Tumor Registry of the United States (CBTRUS). Incidence rates (IRs) and 95% confidence intervals (CIs) were calculated per 100000 person-years (py) and age-standardized to the 2011 Canadian population for comparisons within Canada and to the 2000 United States population for comparisons with the US., Results: Overall, 12515 malignant brain and other CNS tumors were diagnosed in the Canadian population in 2009-2013 (IR: 8.71/100000 py; 95% CI: 8.56, 8.86); 7085 were among males (IR: 10.06/100000 py; 95% CI: 9.82, 10.29) and 5430 among females (IR: 7.41/100000 py; 95% CI: 7.22, 7.61). Of these, 12115 were classifiable according to histological subgroups defined by CBTRUS. The most common histology was glioblastoma (IR: 4.06/100000 py; 95% CI: 3.95, 4.16). Among those aged 0-19 years, 1130 malignant brain and CNS tumors were diagnosed in 2009-2013 (IR: 3.36/100000 py; 95% CI: 3.16, 3.56). The most common histology among the pediatric population was embryonal tumor (IR: 0.74/100000 py; 95% CI: 0.65, 0.84)., Conclusions: These data represent an initial detailed report on the frequency and distribution of primary malignant brain and other CNS tumors diagnosed in the Canadian population in 2009-2013. The reported distributions of tumor diagnoses by sex and age reflected expected patterns based on the literature from similar populations. A report incorporating data on nonmalignant primary brain tumors is forthcoming., (© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Neuro-Oncology.)

Some researchers in other regions have recommended human papillomavirus (HPV) vaccination to reduce risk of ovarian cancer, but not in North America, where evidence has previously suggested no role for HPV in ovarian cancer. Here we use a large sample of ovarian cancer transcriptomes (RNA-Seq) from The Cancer Genome Atlas (TCGA) database to address whether HPV is involved with ovarian cancer in North America. We estimate that a known high-risk type of HPV (type 18) is present and active in 1.5% of cases of ovarian epithelial cancers in the US and Canada. Our detection methods were verified by negative and positive controls, and our sequence matches indicated high validity, leading to strong confidence in our conclusions. Our results indicate that previous reports of zero prevalence of HPV in North American cases of ovarian cancer should not be considered conclusive. This is important because currently used vaccines protect against the HPV-18 that is active in ovarian tumors and, therefore, may reduce risk in North America of cancers of the ovaries as well as of the cervix and several other organ sites.

Purpose: This study examines the changing epidemiology of paediatric brain tumours over the past three decades (1980-2008) in a single institution, SickKids, Toronto, Canada., Methods: We classified 1,866 surgical pathology cases of brain tumours in children under the age of 19 according to the World Health Organization 2007 consensus and analysed them by gender, histological tumour type, age distribution and decade., Results: Males showed a slightly higher predominance with 56.8% of cases overall. The main histological tumour types were low-grade (I/II) astrocytomas (26.4%), medulloblastoma (10.6%), anaplastic astrocytoma/glioblastoma multiforme (7.1%) and ependymoma (7.0%). Over three decades, an increasing proportion of certain tumour types, including pilocytic astrocytoma, atypical teratoma/rhabdoid tumours and neuronal/mixed neuronal-glial tumours was seen., Conclusions: Our results are consistent with those published with similar methodologies in other countries. Any changes in the epidemiology of childhood central nervous system tumours over the past three decades may be attributed in part to changing classification systems, improved imaging technologies and developments in epilepsy surgery; however, continued surveillance remains important.

Background: The relationship between occupational exposure to magnetic fields and brain cancer in men was investigated using population-based case-control data collected in eight Canadian provinces. Emphasis was placed on examining the variations in risk across different histological types., Methods: A list of occupations was compiled for 543 cases and 543 controls that were individually matched by age. Occupations were categorized according to their average magnetic field exposure through blinded expert review (<0.3, 0.3-<0.6, and > or = 0.6 microT). In total, 133 cases (14%) and 123 controls (12%) were estimated to have at least one occupation whereby magnetic field exposures exceeded 0.3 microT. Odds ratios (OR) were generated using conditional logistic regression, and were adjusted for suspected occupational risk factors for brain cancer., Results: A non-significantly increased risk of brain cancer was observed among men who had ever held a job with an average magnetic field exposure >0.6 microT relative to those with exposures <0.3 microT (OR = 1.33, 95% CI : 0.75-2.36). A more pronounced risk was observed among men diagnosed with glioblastoma multiforme (OR = 5.36, 95% CI : 1.16-24.78). Moreover, a cumulative time weighted index score of magnetic field exposure was significantly related to glioblastoma multiforme (P = 0.02). In contrast, magnetic field exposures were not associated with astrocytoma or other brain cancers., Conclusions: Our findings support the hypothesis that occupational magnetic field exposure increases the risk of glioblastoma multiforme.

In this clinical and histopathological study, the frequency of long-term glioblastoma multiforme (GBM) survivors (LTGBMSs) was determined in a population-based study. The Alberta Cancer Registry was used to identify all patients diagnosed with GBM in Alberta between January 1, 1975, and December 31, 1991. Patient charts were reviewed and histology reexamined. LTGBMSs were defined as GBM patients surviving 3 years after diagnosis. Each LTGBMS was compared with 3 age-, sex-, and year of diagnosis-matched controls, and patient/treatment or tumor characteristics that predicted long-term survival were determined. There were 689 GBMs diagnosed in the study period; 15 (2.2%) of these patients survived 3 years. LTGBMSs (average age, 43.5 +/- 3.3 years) were significantly younger when compared with all GBM patients (average age, 53.0 +/- 0.56 years). LTGBMSs had a higher Karnofsky Performance Status score at diagnosis compared with controls. LTGBMSs were much more likely to have had a gross total resection and adjuvant chemotherapy than control GBM patients. Tumors from LTGBMSs tended to have fewer mitoses and a significantly lower Ki-67 cellular proliferation index compared with controls. Radiation-induced dementia was common and disabling in LTG-BMSs. In conclusion, conventionally treated GBM patients in an unselected population have a very small chance of long-term survival. The use of aggressive surgical resection and adjuvant chemotherapy may make long-term survival more likely in GBM patients if their performance status is high at diagnosis.