Assessing the risk of unsuspected prostate cancer in patients with benign prostatic hypertrophy: a 13-year retrospective study of the incidence and natural history of Tla-Tlb prostate cancers

Objective To determine the incidence and natural history of stage T1a-T1b p rostate cancer in patients undergoing surgery for benign prostatic hypertro phy (BPH), and thus evaluate the effect that recent medical and 'minimally invasive' treatments (which provide no prostate sample for pathological exa mination) might have on the percentage of patients with unsuspected prostat e cancer. Patients and methods A series of 1648 patients undergoing surgery for BPH o ver a 13-year period were reviewed retrospectively; the period overlapped t he introduction of serum prostate specific antigen (PSA) as a detection met hod. Results Stage T1 prostate cancer was found in 182 patients (11%), comprisin g 126 (11%) of 1199 transurethral resections and 56 (12%) of 449 open enucl eations. The introduction of systematic PSA assays gradually reduced the me an incidence of T1 cancer from 23% to 7%, with a greater effect on T1b (fro m 15% to 2%), while the incidence of T1a remained nearly constant (+/- 5%). The pathological features of surgical specimens from 43 radical prostatect omies undertaken for T1 tumours were reviewed. Locally advanced disease (st age greater than or equal to pT3) was apparent in 13% of T1a and 28% of T1b tumours. Amongst the patients electing for surveillance, only 8% of those with T1a progressed within 30-97 months of follow-up (mean progression time 73 months), whereas 29% of those with stage T1b progressed within 36 month s of follow-up (mean progression time 17 months). Conclusion These results show that the use of the PSA assay has decreased b ut not suppressed the incidence of pT1 prostate cancer, with a greater effe ct on those tumours at higher risk of progression (T1b). This suggests that the detection of prostate cancer based on PSA and transrectal ultrasonogra phy is appropriate for screening patients and is sufficiently accurate that treatments for BPH that provide no pathological materials can be applied s afely.