[818] Cancer to Prostatic Urethra Distance in Radical Prostatectomy: Implications for Urethral Thermoprotection in Prostate Cryoablation Surgery

C Magi-Galluzzi, S Jones, AV Hernandez, M Zhou. Cleveland Clinic, Cleveland, OH

Background: Cryoablation is a viable option for prostate cancer (PCa) patients who are not candidates for prostatectomy. A heating coil is placed in and portects the prostatic urethra from the cryo injury. The tissue within certain depth beneath the urethral mucosa, including PCa in that zone, is therefore not cryoablated. The cancer to prostatic urethra distance and the preoperative predictors of such distance are important for urologists and patients to decide if to undergo cryoablation.
Design: PCa was mapped in radical prostatectomy (RP) speciments and the shortest distance between the prostatice urethra and PCa was measured. The distance was then correlated with the preoperative serum PSA levels as well as prostate biopsy parameters, including Gleason score (GS), number of positive cores, highest % of positive cores, cancer in apex and bilateral disease.
Results: 100 RPs were studied. Patients' mean age was 58.6 (range 39-75) years. Preoperative serum PSA was 6.4 (range 1.6-23) ng/ml. Cancer to urethra distance was 0 (cancer at the urethra), 0.1-1, 1-2, 2.1-3, 3.1-4, 4.1-5 and >5 mm in 4, 19, 30, 14, 15, 7 and 11 cases, respectively. Bilateral PCa was marginally associated with shorter distance to the urethra (2.4 mm vs. 3.2 mm in bilateral and unilateral PCa, respectively; p=0.07). There was also a marginal association between PSA level and distance to the urethra. For one unit of PSA increment, the distance to the urethra decreased 0.12 mm (Pearsoncorrelation=0.19, p=0.06). No association was found between the distance and biopsy GS, number of positive cores, highest % of positive cores and cancer in apex.
Conclusions: In 100 RPs, PCa was at the urethra in 4% cases, and within 5 mm of the urethra in 91% cases. Most of the preoperative biopsy parameters, including GS, number of positive cores, highest % of positive cores and cancer in apex, did not correlate with the cancer to urethra distance. Only bilateral PCa and serum PSA levels marginally correlated with such distance. Our study indicates that the preoperative estimation of the cancer to urethra distance still have to rely on the imagining study; serum PSA and bilaterality of PSA may be helpful.
Category: Genitourinary (including renal tumors)

Wednesday, March 11, 2009 9:30 AM

Poster Session V # 122, Wednesday Morning