Probability Of Extracapsular Extension Research Articles

MP80-06 INTRAOPERATIVE BIMANUAL EXAMINATION AND FROZEN-SECTION ANALYSIS DURING ROBOT-ASSISTED RADICAL PROSTATECTOMY: A NOVEL TECHNIQUE FOR REDUCING POSITIVE SURGICAL MARGINS

INTRODUCTION AND OBJECTIVES: To describe the feasibility and early outcomes of a Modification to robot-assisted radical prostatectomy (RARP) that allows for mitigation of the lack of tactile feedback during RARP by allowing immediate Organ Retrieval for Examination and targeted frozen-section biopsies (MORE technique). METHODS: MORE consists of a GelPOINT device inserted periumbilically. Prostate is excised and retrieved through the GelPOINT without undocking the robot, and examined bimanually on-table by the surgeon. Lesions suspicious for positive surgical margin (PSM) are sent for frozen section analysis (Figure). Biopsies positive/suspicious for cancer resulted in more tissue excision from the corresponding pelvic bed site. 352 patients with a probability of extracapsular extension (EPE) >25% (Partin table) were selected to undergo MORE RARP. MORE RARP patients with pT3a at final pathology (n1⁄4103) were compared to a control group of 74 consecutive patients with pT3a after conventional RARP. RESULTS: Except a greater proportion of clinically palpable disease in the MORE RARP vs. control group (43.7 vs. 17.6%; p1⁄40.005), the two groups had comparable rates of nodal dissection, nerve sparing, pathological stage, grade and nodal status. The PSM rate in the MORE group was 17.5% (18/103) compared to 36.5% (27/74) in the control group (p1⁄40.004); the odds ratio was 0.37 (CI: 0.18-0.74; p1⁄40.005). 8 patients in each group had biochemical recurrence; short follow-up (median 16.6 and 15.4 months respectively) precluded detection of any significant difference. Frozen section biopsy site matched the EPE site at final pathology in 59/79 (73.4%) cases selected for frozen section analyses. CONCLUSIONS: Adoption of the MORE technique led to a significant reduction in the PSM rate following RARP in patients harboring locally advanced disease without increasing operative time. Its easy reproducibility may also allow potential utility in other robotassisted urologic oncologic procedures. Source of Funding: none

845 BIMANUAL EXAMINATION OF RETRIEVED SPECIMEN DURING ROBOT-ASSISTED RADICAL PROSTATECTOMY: A NOVEL TECHNIQUE FOR REDUCING THE POSTIVE SURGICAL MARGIN

INTRODUCTION AND OBJECTIVES: A putative drawback of robot-assisted radical prostatectomy (RARP) is the lack of tactile sensation and the ability to determine possible tumor margins. We describe a modified technique of RARP that allows immediate organ retrieval for intraoperative examination and targeted frozen section biopsies (MORE procedure). The aim of this study was to determine feasibility and early outcomes. METHODS: 117 patients with a probability of extracapsular extension (EPE) 25% by Partinos tables were selected to undergo MORE-RARP. MORE consists of a GelPOINT” access port (Applied Medical, CA, USA) placed in the periumbilical region with a 12mm camera port and 10mm port for retrieval. Following excision of the prostate, it is retrieved through the GelPOINT, and examined on-table by the surgeon. Lesions suspicious for positive margins are sent for frozen section biopsy. Biopsies positive or suspicious for cancer resulted in more tissue being removed. Patients undergoing MORE with pT3a at final pathology were compared to a control group of patients with pT3a after conventional RARP. RESULTS: In the MORE group, 30 out of 117 patients were diagnosed with pT3a disease. There were no significant differences in baseline characteristics between control patients and patients undergoing MORE procedure. 8/30 patients in the MORE group and 5/30 patients in the control group had GS 8 at biopsy. Total operating times between MORE vs control groups were not significantly different (182.5 vs 175.9 minutes respectively, p 0.69). The PSM rate in the control group was 43.3% (13/30) compared to 16.7% (5/30) in MORE (p 0.047), and the relative risk ratio was 2.6 (CI: 1.06 6.33; p 0.037) (Table 1). In 70.8% of MORE, the site selected for frozen section biopsy matched the EPE site at final pathology. CONCLUSIONS: Using GelPoint allowed to examine the retrieved prostate bimanually. In this pilot study, adoption of the MORE procedure at RARP led to a significant reduction in the PSM rate in pT3a prostate cancer. MORE is a promising technique that has potential in other minimally invasive urologic oncologic procedures.

Prediction of extracapsular extension of prostate cancer based on systematic core biopsies

To evaluate the clinical utility of transrectal ultrasound-guided systematic sextant or octant biopsies for the prediction of extracapsular extension (ECE) at radical prostatectomy. We performed a retrospective analysis of 84 patients who underwent preoperative staging and transrectal ultrasound-guided systematic sextant (n=60) or octant (n=24) biopsy. The presence of ECE was correlated with the number of positive biopsies on each side of the prostate by chi(2) analysis. Sensitivity, specificity and positive and negative predictive values were calculated for both positive (two or three positive biopsies per side) and negative (none or one positive biopsy per side) test results. The number of positive cores was thereafter combined with two other parameters: prostate-specific antigen (PSA) level and Gleason score. ECE was evidenced at radical prostatectomy in 24% of patients (20/84). chi(2) analysis demonstrated a significant correlation between the number of positive biopsies and the presence of ECE. Analysis of the 168 prostate sides and dominant sides revealed that systematic needle biopsies had positive predictive values of 46.7% and 37%, respectively and negative predictive values of 89% and 94%, respectively. Use of a combination of parameters (biopsy Gleason score > or =7 vs <7; PSA >10 vs < or = 10 ng/ml; and >1 positive core vs none or one positive cores) identified patients at high or low risk of ECE. At the extremes, none of the 10 patients in the low-risk group had ECE at radical prostatectomy, compared to 77% of those in the high-risk group. The probability of ECE at radical prostatectomy can be accurately predicted based on the number of positive sextant and octant biopsies, either alone or in combination with other parameters.

Statistical Modeling Using Preoperative Prognostic Variables in Predicting Extracapsular Extension and Progression after Radical Prostatectomy for Prostate Cancer

To predict the risk of extracapsular extension and postoperative recurrence before radical prostatectomy (RP) for prostate cancer. We performed multivariate Cox regression analysis on preoperative variables in 260 clinically localized prostate cancer patients who underwent RP. With these data, we constructed a relative risk of recurrence (Rr) equation and an equation to predict the probability of extracapsular extension (PECE) before RP. Rr is calculated as exp[(0.47 x race + 0.14 x PSAST) + (0.13 x worst biopsy Gleason sum) + (1.03 x stage T1c) + (1.55 x stage T2b,c)], where PSAST indicates a sigmoidal transformation of prostate-specific antigen. PECE is calculated as 1/[1 + exp(-Z)], where Z = -2.47 + 0.15 (PSAST) + 0.31 (worst biopsy Gleason sum) + 0.18 (race) + 0.16 (stage T1c) + 0.38 (stage T2b,c). These two equations can be used preoperatively to predict the probability of extracapsular disease and the risk of prostate-specific antigen recurrence in patients undergoing RP.

Systematic sextant biopsies in the prediction of extracapsular extension at radical prostatectomy

To evaluate the clinical utility of transrectal ultrasound-guided systematic sextant needle biopsies in the prediction of extracapsular extension (ECE) at radical prostatectomy. A retrospective analysis of 104 men who underwent systematic biopsy and radical prostatectomy at our institution was performed. All patients underwent preoperative staging by transrectal ultrasound and transrectal ultrasound-guided systematic sextant biopsy. The presence of pathologic ECE was correlated to the number of positive core biopsies on each side of the prostate by chi-square analysis. Sensitivity, specificity, positive and negative predictive values, and likelihood ratios (LRs) were calculated for both positive (two or three biopsies positive per side) and negative (no or one positive biopsy per side) test results. Forty-two (20.2%) of 208 sides demonstrated evidence of ECE at radical prostatectomy. Chi-square analysis demonstrated a significant correlation between the number of positive biopsies and the presence of ECE at radical prostatectomy (P = 0.001). Overall, the finding of multiple positive core biopsies (two or three per side) had predictive value with regard to the presence of ECE (sensitivity 62%, specificity 77%, positive predictive value 40%, negative predictive value 89%). The corresponding LRs were 2.5 for a positive and 0.5 for a negative test result. The probability of ECE at radical prostatectomy can be more accurately assessed preoperatively by the combined use of transrectal ultrasound and systematic sextant needle biopsies.