Cancer research needs standardized data throughout Germany

Up until recently, scientists relied primarily on the data of the Saarland cancer registry for studying questions about the incidence or age distribution of specific cancer types in Germany. Although these data represent only about 1.3 percent of the German population, they were projected to the whole of Germany. By now, all German Federal States have established their own cancer registries. The state registries are collaborating in the Association of Population-based Cancer Registries in Germany (GEKID). “GEKID’s primary goal is to achieve nationwide uniform standards for methods and contents despite differing legal regulations at the federal state level. This is the only way to make the results of the cancer registries comparable among each other,” says Professor Nikolaus Becker of DKFZ, who leads the population-based cancer registry of Baden-Württemberg.

Moreover, GEKID initiates joint research activities aimed at using the nationwide treasure of data for scientific purposes. The projects of the working group “Surviving After Cancer” are among the current topics of the Heidelberg conference. Supported by funds of the German Cancer Aid (Deutsche Krebshilfe), the group has already published several studies based on the cancer diagnoses of the years 1997 to 2006. The data material which is being analyzed in Professor Hermann Brenner’s department of DKFZ represents eleven of the 16 German Federal States. The DKFZ epidemiologists also train their colleagues of the state registries in the use of specific statistical analysis methods such as period analysis, which makes it possible to generate especially up-to-date survival statistics.

The GEKID working group can now access data representing 33 million Germans. “This enables us to even make statements about less common cancer types such as brain tumors,” Hermann Brenner explains. For the most common cancer types, the working group has calculated that mean survival times are almost the same for patients in Germany and in the U.S.A. Patients with stomach, pancreatic and kidney cancers as well as Hodgkin’s lymphoma even have slightly longer survival times in Germany. The GEKID working group will conduct further studies to find out, among other things, how socioeconomic factors impact survival after cancer diagnosis.

Another research project will be launched at the Heidelberg conference: The researchers have obtained first evidence suggesting that the incidence of advanced stage colorectal cancer cases in Germany is declining. On the basis of the cancer registry data, they will now investigate whether this decline is attributable to the introduction of the bowel cancer screening program.

“We provide the data basis for many nationwide research projects and we ensure, above all, a high quality of the data,” says GEKID Chairman, Professor Alexander Katalinic. Thus, the success of the mammography screening program could not even be evaluated without cancer registry data. Future population-based studies such as the National Cohort, which aims to determine the causes of cancer and other chronic diseases, would hardly be feasible without reconciling data with the cancer registries. “It is all the more important that all cancer registries in Germany collaborate closely across state borders,” says Katalinic.