Brain cancer incidence and mortality–comparisons between Switzerland and Georgia

Tumours of the brain and the central nervous system (brain/CNS) include a collection of neoplasms (gliomas, meningiomas, and acoustic neuromas) that vary widely by the degree of malignancy. Aside from increasing age, high-dose radiation, and some hereditary syndromes, no risk factors for these tumours have been established and their etiology remains largely unknown (Bondy ML et al, Cancer 2008). They are rather infrequent with respect to incidence rates, but the mortality from this disease is high. Since brain/CNS tumours frequently occur at a younger age than tumours at other sites, they have a strong impact on years of potential life lost due to cancer. For example, in Switzerland, for the years 2003-2007, brain/CNS tumours ranked 15 with respect to incidence, but second with respect to years of potential life lost in men (NICER & FSO 2009).

Data from 39 countries indicates large variability in the rates of diagnosis of new cases of brain/CNS cancer–with a 5-fold difference between the highest rates (mainly in Europe) and the lowest (mainly in Asia) (Miranda-Filho A et al, Neuro Oncol 2017). The observed variation between countries might be due partly to differences in health systems infrastructure, access to care, and the availability of diagnostic services. However, quality and availability of incidence data in low and medium income countries is a critical consideration as well.

The Cancer Registry Zurich/Zug in Switzerland was established in 1980 in the canton of Zurich and expanded to include the canton of Zug in 2011. Each year, about 120 incident malignant brain/CNS tumours (ICD-10 C70-C72) and about 200 benign cases (D32-D33, D42-D43) are registered in Zurich. The registry receives notifications (personal information, tumour characteristics) from pathology and hematology laboratories, hospitals, and physicians as well as death certificates from the Swiss Federal Statistical Office (Wanner M et al., Biomed Res Int. 2018).

The Georgian Brain Tumour Data Bank was established in 2008 by Dr.Gigineishvili and team from the Department of Neurology & Neurosurgery at the Tbilisi State University and was supported by Rustaveli National Science Foundation. Data are collected from fifteen different hospitals, which provide neurosurgical and neuroradiological services and numerous ambulatory-based CT and MRI units in three large cities (Tbilisi, Kutaisi and Batumi). Active case ascertainment captures all cases of newly diagnosed brain/CNS tumours.

The main aim of the proposed study is to compare brain/CNS cancer incidence, mortality and survival between a cancer registry in Switzerland, a high-income country with a universal health care system that provides basic health care for all, and Georgia, a former Soviet republic that became independent in 1991 and is considered a lower middle income country by the World Bank (https://data.worldbank.org/?locations=GE-XN). Our team has previously evaluated differences in cancer epidemiology between the canton of Zurich and the city of Sofia (Bulgaria; Dehler S et al., Tumouri 2014).

Participants: