[Cancer and age or: Cancer as a finite urn model].

The consideration is based on a finite urn model (drawn balls are not returned). One important conclusion is that increasing effects of selection on the surviving population are to be assumed only by selection of death. Inaccuracy of official death rates results from insufficiency in registration of the confidential part of death certificates. 57% (in females) and 58% (in males) of all malignant tumors (based on examinations in the presented autopsy material) are found beyond the age of 60. More rare than expected are multiple tumors: formal arguments for this are discussed, the phenomenon being explained by a considerably increased death rate. The spectrum of target organs for metastases in the age groups (over 60 years) is tabulated for the oesophagus, stomach, colon-rectum, lung, mamma and prostata as primary tumor localization. As it matastasizes each primary tumor localization shows a specific time course and a specific organ selection. The correlation between malignant tumors and concomitant non tumorous diseases is given special attention. The latter are regarded as indicator for the pathogenesis of tumor diseases. The conclusions are that the remaining population in the urn model is highly selected. This becomes more pronounced in the older and most advanced age groups.