[Therapy of local prostate carcinoma. Questions answered by outcome research].

More and more localized prostate cancers with only a low risk for progression are diagnosed. In most cases the treatment consists of invasive procedures which may be accompanied by certain side effects. Ongoing randomized studies which are comparing irradiation and surgery with defensive strategies like Active Surveillance will not give results in the foreseeable future. In this situation it could be helpful to take data from health care research studies like HAROW. Neither the physicians nor the patients participating are selected. As a non-interventional study HAROW provides a data collecting in invasive therapies and in defensive strategies. Under everyday conditions data on cancer history, quality of life, patients' satisfaction and economics are collected. Since Active Surveillance (AS) is still a largely uncommon strategy we present criteria for enrollment, ongoing and termination. In international guidelines AS is assessed to be on a par with invasive procedures or even as the preferred treatment option.