[Survival chances of Hungarian cancer patients in the National Cancer Registry]

Abstract

The Hungarian National Cancer Registry (HNCR) was launched in August, 1999 by the National Cancer Institute. The main goal of HNCR is to determine the prevalence of different types of malignant cancers. A new method, period analysis was invented to determine survival chances of patients with malignant tumor. Based on period analysis we developed a new method by approximating survivals of Hungarian cancer patients with the help of Gompertz distribution. Our survival analysis was based on HNCR data of patients with cancer recognized between January 1, 2002 and December 31, 2005. These data are far enough from the time when HNCR started, thus they do not contain the initial errors, but also far enough from the present so their correction could be considered completed. In case of 21 malignant tumor locations for males and 23 ones for females we determined the parameters of the Gompertz distribution and based on the estimated parameters we estimated the expected survival probabilities for each specific tumor type and gender. In this study we have not used the TNM-based clinical stage or any other data of the patients contained by HNCR. Using the Gompertz model, the complete recovery of a cancer patient is always possible and the probability of recovery has a reliable estimate based on a short follow-up period only. We compared our results with five-year survival data of Canada, Italy, Norway and Finland and we did not find substantial differences. For both men and women, considering any specific location, the differences in survival among countries are much smaller than the difference between locations.