Undetectable ultrasensitive PSA after radical prostatectomy for prostate cancer predicts relapse-free survival

Radical retropubic prostatectomy is considered by many centres to be the tr eatment of choice for men aged less than 70 years with localized prostate c ancer. A rise in serum prostate-specific antigen after radical prostatectom y occurs in 10-40% of cases. This study evaluates the usefulness of novel u ltrasensitive PSA assays in the early detection of biochemical relapse. 200 patients of mean age 61.2 years underwent radical retropubic prostatectomy . Levels less than or equal to 0.01 ng ml-1 were considered undetectable. M ean pre-operative prostate-specific antigen was 13.3 ng ml-1. Biochemical r elapse was defined as 3 consecutive rises. The 2-year biochemical disease-f ree survival for the 134 patients with evaluable prostate-specific antigen nadir data was 61.1% (95% Cl: 51.6-70.6%). Only 2 patients with an undetect able prostate-specific antigen after radical retropubic prostatectomy bioch emically relapsed (3%), compared to 47 relapses out of 61 patients (75%) wh o did not reach this level. Cox multivariate analysis confirms prostate-spe cific antigen nadir less than or equal to 0.01 ng ml-1 to be a superb indep endent variable predicting a favourable biochemical disease-free survival ( P < 0.0001). Early diagnosis of biochemical relapse is feasible with sensit ive prostate-specific antigen assays. These assays more accurately measure the prostate-specific antigen nadir, which is an excellent predictor of bio chemical disease-free survival. Thus, sensitive prostate-specific antigen a ssays offer accurate prognostic information and expedite decision-making re garding the use of salvage prostate-bed radiotherapy or hormone therapy. (C ) 2000 Cancer Research Campaign http://www.bjcancer.com.