[Ten years national research project "familial prostate cancer": problems in identifying risk families]

The German national research project"familial prostate cancer" has been recruiting prostate cancer patients nationwide since 1999. In 2009, a comprehensive data analysis of the 25,065 families recruited was performed. Of these, 77.4% were identified as sporadic, 20.0% as familial and 2.6% as hereditary cases of prostate cancer. However, obtaining comprehensive, validated information about all relatives often fails.

The high average age of the patients, the lower life expectancy in further generations and the low number of first-degree male relatives hampers the classification of sporadic, familial and hereditary cases. Consequently we describe here that in our database the identification of 100 hereditary cases requires a recruitment of more than 5,000 patients with their families. For 100 sporadic patients with 2 first-degree male relatives without a case history 1,250 patients are needed.