HAROW: the first comprehensive prospective observational study comparing treatment options in localized prostate cancer

Purpose To collect data on primary treatment decision and follow-up in patients with diagnosed, histologically confirmed localized (T1a–T2c/N0/M0) prostate cancer (PCa) for up to 5 years in a prospective observational non-interventional study. Methods Patients were non-randomly allocated to one of the five treatment strategies: hormone therapy, active surveillance, radiation, operation, or watchful waiting. Results A total of 3169 patients were included by 259 participating sites; 2957 patients had at least one follow-up visit. 54.8 % of tumors at baseline were staged as T1c, 38 % as T2a–T2c, and 7.1 % as T1a or T1b (missing: 0.2 %). 38.9, 32.6 and 26.6 % of patients were classified as low risk, intermediate risk, and high risk according to d’Amico, respectively (missing: 1.8 %). 56.6 % of patients underwent prostatectomy as primary therapy, 16.4 % received radiation, 6.9 % HT, 15.8 and 4.3 % decided for AS or WW. Mean follow-up was 28.4 months. Progression rates were between 8.6 % (RT) and 33.1 % (AS). Conclusion Whereas RP remains the main treatment option of localized PCa, active surveillance appears to become an accepted and selectively employed treatment option. Careful selection of patients is documented by the highest proportion of patients with low risk (82.5 %), PSA density 3 months.