[758] Can Saturation Biopsy Predict Significant Cancer Nodule Localization in Radical Prostatectomy Specimens: A Correlative Study and Implications for Focal Therapy for Prostate Cancer

SM Falzarano, M Zhou, E Kodjoe, M Gong, JS Jones, C Magi-Galluzzi. Cleveland Clinic, Cleveland; Glickman Urological Institute, Cleveland, OH

Background: Focal therapy for prostate cancer using non-prostatectomy approach, such as cryoablation, has been increasingly gaining acceptance for patients who are not candidates for radical prostatectomy (RP). The success of focal therapy relies on the accurate mapping, using transrectal biopsy, of the significant cancer nodules in the prostate gland before the procedure.
Design: Seventy-two consecutive patients underwent saturation needle biopsy of the prostate (Bx) followed by RP for PCa performed at our institution from August 2003 to October 2007. The biopsy protocol consisted of traditional sextant, plus an additional 12 cores focused in the lateral peripheral zone and apex. All RP specimens were reviewed by a single pathologist, who mapped the tumor outline, determined the number of separate foci of PCA, their volume (TV), zone of origin and Gleason score (GS). The locations of tumor on Bx and RP were correlated.
Results: The median age and preoperative PSA of the patients was 60 years (range 38-75) and 6.9 ng/mL (range 1.2-27.7), respectively. The prostate specimen median weight was 48 g (range 25-274). In 37 (51.4%) men, the Bx findings correlated with the RP findings. In the remaining 35 patients (48.6%), 51 PCA foci, ranging from 1 to 4 per RP, were missed by Bx. Of the 51 missed PCA foci, 32 were significant PCA (>5 mm and GS6). The significant PCA were GS6 (n=22) and GS7 (n=10); their TV ranged from 8 to 200 mm; the location was distributed as follows: 14 transitional zone (TZ) (44%), 7 apex/anterior zone (22%), 7 mid peripheral zone(22%) and 4 posterior peripheral zone (12%). In 39/72 (54.2%) cases, the Bx was positive only on one side (right in 26 and left in 13 cases), meanwhile the RP specimen showed significant PCA in both sides in 22 specimens (false negative [FN])(negative predictive value [NPV] = 43.6%). There was no statistical difference in patient's age, PSA, and prostate specimen weight between FN and true negative cases.
Conclusions: A negative saturation needle biopsy does not confirm the absence of PCA in the corresponding side of the RP and cannot be used as single determinant when considering a patient for focal treatment. Considering that most of the PCA foci missed by Bx were located in the transitional zone, TZ biopsies could be suggested before taking surgical decision such as focal therapy.
Category: Genitourinary (including renal tumors)

Wednesday, March 11, 2009 9:30 AM

Poster Session V # 116, Wednesday Morning