Prostate cancer screening: Results of a prospective trial in Canton Aargau, Switzerland

INTRODUCTION: Prostate cancer is the most commonly diagnosed cancer in Swiss men and the second leading cause of cancer related death among them (e.g. CH: 1,267 in year 1998). With the population at risk constantly growing these absolute numbers are expected to further increase. While there is no question that aggressive treatment of localised tumour is required for definitive cure of prostate cancer, the application of screening for early stage disease remains controversial. Since 1998 the Clinic of Urology in Kantonsspital Aarau has participated in the ERSPC (European Randomised Study of Screening for Prostate Cancer) study, which is designed to provide data on prostate cancer screening within a prospective randomised controlled setting. METHODS: Men aged between 55 and 70 years were enrolled in the study. From n = 18,361 men invited by a letter to participate, 7,124 (38.8%) agreed and gave their informed consent to be randomised in either a PSA measurement (n = 3,562, group 1) or a control group (n = 3,562, group 2). Men in group 1 with a PSA level ?3.0 ng/ml, n = 372 (10.5%) then underwent ultrasound guided transrectal sextant biopsy of the prostate. RESULTS: Prostate cancer was detected at presentation in every fourth man biopsied (n = 89). Neither the free-to-total PSA ratio nor the PSA density could significantly spare biopsies while sustaining a high sensitivity level. The overall cancer detection rate amounted to 2.5% in PSA tested men. In 7% (n = 5) distant disease was already present. 93% of men with clinically organ confined disease underwent prostatectomy (n = 59) or radiotherapy (n = 22), whilst only (n = 3) chose to follow a policy of watchful waiting. In 92% the histology of the prostatectomy specimens revealed aggressive cancer characteristics according to the criteria of Epstein et al. CONCLUSIONS: Although the clinically relevant tumour characteristics and the relatively low cancer detection rate of 2.5% (less than the lifetime mortality risk of 3% and the morbidity risk of 8%) seem to justify screening in terms of adequate diagnosis and treatment, follow-up until 2008 is needed to prove the benefit in mortality for the prostate cancer screening group over the control group. Furthermore, information from the ongoing ERSPC study is needed in order to assess uncertainties i.e. the degree of overdiagnosis caused by repeated screening and the quality of life adjusted gain in life years. For daily practice a "PSA grey zone" of 4-10 ng/ml can no longer be postulated as only 70% of men in this range presented with organ confined disease. Once the PSA level exceeds 4.0 ng/ml. prostate biopsy should be performed immediately.