The Value of Serum Prostate Specific Antigen Determinations Before and after Radical Prostatectomy

Abstract

We evaluated serum prostate specific antigen before and after radical prostatectomy. In 100 consecutive patients who underwent radical prostatectomy, preoperative prostate specific antigen levels tended to increase with the increasing severity of pathological stage. However, even at levels of greater than 10 ng. per ml. the positive and negative predictive values (78 and 61 per cent, respectively) of prostate specific antigen to predict extracapsular disease were not sufficient to make this test useful alone for staging. In theory, after radical prostatectomy prostate specific antigen should be zero if no remaining prostatic tissue is present. Tests of precision and analytical sensitivity in our laboratory using a commercial prostate specific antigen assay revealed that a value of 0.4 ng. per ml. or more is different from zero at a greater than 95 per cent confidence level. With this guideline we evaluated the meaning of prostate specific antigen levels 3 to 6 months after radical prostatectomy in 59 men. Among men whose prostate specific antigen level was less than 0.4 ng. per ml. only 9 per cent demonstrated recurrence as evidenced by the development of positive bone scan or progressively elevated prostate specific antigen levels within 6 to 50 months. Alternatively, in men whose 3 to 6-month prostate specific antigen level was 0.4 ng per ml. or more there was evidence of recurrence in 100 per cent within 6 to 49 months (p less than 0.0001). Progressively elevated (more than 0.4 ng. per ml.) prostate specific antigen levels preceded recurrence from 12 to 43 months in all 6 patients who had positive bone scans, while increasing prostate specific antigen levels since radical prostatectomy have continued from 9 to 65 months in the 11 patients who have no radiological evidence of recurrent disease to date. Prostatic acid phosphatase serum values after radical prostatectomy were not useful to predict persistent disease. Prostate specific antigen values 3 to 6 months after radical prostatectomy are a sensitive indicator of persistent disease after radical prostatectomy and often precede other evidence of this occurrence by many years. This fact may alter concepts about surgical results, and possibly shorten and sharpen clinical studies involving adjuvant therapy after radical prostatectomy.

Prostate‐specific antigen: A review of the validation of the most commonly used cancer biomarker

“…The earliest observations had important clinical applications and included: 1) a decrease in the PSA level after hormonal therapy appeared to be correlated with response to treatment [11][12][13] ; 2) an increase in the PSA level after treatment appeared to precede and herald disease recurrence 11,14,15 ; and 3) after radical prostatectomy, PSA should be undetectable; if not, disease recurrence is the rule. 11,14,15 Several of these early investigators rejected the possibility of using PSA for screening because of a substantial overlap in PSA values between patients with and those without carcinoma and the resulting poor test specificity. 11,16,17 Recognizing the critical nature of specificity in a screening tool for prostate carcinoma, Guinan et al established an ULN for PSA of 24 ng/mL in a case-control study.…”

Case study: management of advanced prostate cancer with soft tissue metastases

“…For men whose postoperative PSA level remains at 40.4 ng/ml, as in this case, the PSA progression rate approaches 100%. 1 Such patients are at increased risk of developing metastases 2 and should be considered for second-line radiotherapy and/or hormonal therapy.…”

Local therapy for prostate-specific antigen recurrence after definitive treatment

“…Typically, biochemical failure precedes clinical disease by 6 to 48 months. 27 Pound et al characterized disease progression after PSA elevation in patients undergoing radical prostatectomy. Actuarial time to metastases was 8 y from the time of PSA failure and was predicted by time to biochemical failure, Gleason score, and PSA doubling time.…”