Proximity of prostate cancer to the urethra: Implications for minimally invasive ablative therapies

Objectives, The delivery of thermotherapy, cryotherapy, and interstitial ra diation with minimal morbidity is dependent on the preservation of the pros tatic urethra. Our aim was to determine the distribution of the distance be tween the urethra and the nearest prostate cancer. Methods, We determined the location of cancer in 350 prostate cancers treat ed by radical prostatectomy between 1991 and 1993. Each pathologic specimen was totally embedded, serially sectioned, and whole mounted. For each pros tate, the radial distance from the urethra to the nearest cancer was determ ined (urethral-cancer distance). The urethra-cancer distance was correlated with the clinical, pathologic, and laboratory factors. Univariate and mult ivariate associations with progression-free survival were determined. Results. The mean follow-up was 6.1 years. Ninety-three patients had bioche mical, local, or systemic cancer recurrence. The mean +/- SD distance from the urethra to the nearest cancer was 3 +/- 3 mm (range 0 to 18). In 58 pat ients (17%), the cancer touched the urethra. A decreasing urethra-cancer di stance was associated with increasing rates of cancer recurrence (P = 0.009 ). The urethra-cancer distance correlated with each of the following preope rative factors: preoperative prostate-specific antigen (r = -0.22, P <0.001 ), Gleason score in biopsy specimen (r = -0.13, P = 0.02), and percentage o f Gleason score 4 or 5 in the biopsy specimen (r = -0.17, P = 0.008). Conclusions. The distance between the urethra and the nearest cancer was as sociated with prostate cancer outcome. Many patients have cancer close to t he urethra. This finding may have implications for nonsurgical ablative the rapies for prostate cancer. UROLOGY 56: 726-729, 2000. (C) 2000, Elsevier S cience Inc.