Factors predicting cancer detection in biopsy of the prostatic fossa after radical prostatectomy

Abstract

Objectives: To determine whether the results of anastomotic biopsy for prostate-specific antigen (PSA) recurrence after radical prostatectomy could be predicted by either PSA, PSA velocity, digital rectal examination (DRE), transrectal ultrasound (TRUS), or the interval from prostatectomy to biopsy.

Methods: TRUS with biopsy of the anastomosis was performed for 91 postprostatectomy patients who had either an abnormal DRE or detectable PSA (greater than 0.2 ng/mL). The biopsy results were correlated with the findings of DRE, TRUS, PSA, PSA velocity, interval to PSA recurrence, and with the pathologic stage.

Results: Of 131 examinations, there were 50 positive biopsy specimens for a detection rate of 38%. Of 34 patients with PSA 1.0 ng/mL or less, 8 (24%) had positive biopsy (P = 0.02). A negative DRE lowered (but did not eliminate) the probability of a positive biopsy. Of 100 patients with normal DRE, 28 (28%) had positive biopsy. None of the 11 patients with a negative DRE and a PSA of 0.5 ng/mL or less had a positive biopsy (P = 0.02). The mean interval between prostatectomy and biopsy was significantly greater in patients who had a positive biopsy (45 +/- 39) than in patients with a negative biopsy (27 +/- 21) (P = 0.001). The pathologic stage, Gleason score, and PSA velocity were not helpful in predicting the results of biopsy.

Conclusions: Although patients with a negative DRE can have a positive biopsy and patients with a PSA of 1.0 ng/mL or less can have a positive biopsy, no patient with a negative DRE and a PSA of 0.5 ng/mL or less has a positive biopsy.