[914] Utility of Intraoperative Frozen Section in Assessing the Surgical Margin of Robotic Prostatectomy Specimens

GQ Xiao, DB Samadi, S Noreen, M Mikulasovich, F Nabizada-Pace, PD Unger. Mount Sinai School of Medicine, New York, NY

Background: Intraoperative frozen section utilized to achieve surgical margin free of prostatic glands has rarely been reported in robotic prostatectomy.
Design: From 584 robotic prostatectomies performed between '07 - '08, frozens were sent in 116 cases. Frozens were requested by the surgeon because of visual suspicion for prostatic glands at the prostatic bed. To evaluate the utility of frozen in assessing prostatic glands (benign/malignant) at the periphery of the specimens, all the frozen and corresponding permanent sections from these cases were retrospectively reviewed.
Results: A total of 165 frozens were performed. The results were summarized in Table 1.

Table 1: Summary of the margins and the diagnoses in frozen section (FS) and corresponding permanent section (PS)

115 Frozen sections showing fibromuscular/fibroconnective tissue:

--- PS showing fibromuscular/fibroconnective in 108 cases

-------41 Apex

-------44 Base

-------23 Mid-lateral

--- PS showing benign ptostatic glands in 7 cases

-------4 Base

-------2 Mid-lateral

-------1 Apex

39 FS showing benign prostatic glands

--- PS showing benign prostatic glands in 38 cases

--------8 Apex

--------22 base

------- 8 Mid-lateral

--- PS reverted into prostatic carcinoma in 1 case

9 FS showing prostatic carcinoma

--- PS showing ptostatic carcinoma in 8 cases

-------2 Apex

-------3 Base

-------3 Mid-lateral

--- PS reverted into benign prostatic tissue in 1 case

The predictive value of a positive and negative carcinoma by frozen was 89% and 97%, respectively. The positive predictive value of a negative prostatic gland by frozen was 93%. When prostatic glands were present on frozen, the predictive value of a positive carcinoma by frozen was 19%. The predictive value of a positive prostatic gland (including carcinoma) by intraoperative macroscopic assessment was 34%.
Conclusions: Frozen section has both high positive and negative predictive values in assessing prostatic glands/carcinoma. Given the adverse effect of a carcinoma margin on disease recurrence and survival, a 19% of positive predictive value for carcinoma when prostatic glands present on frozen merits an attention and obtaining of a margin free of prostatic glands should be sought. Intraoperative macroscopic assessment has low predicative value for prostatic glands, which may be related to the degree of accuracy of the examining device used. In conclusion, frozen section is a reliable method to obtain margins free of prostatic glands, including carcinoma.
Category: Genitourinary (including renal tumors)

Tuesday, March 10, 2009 9:30 AM

Poster Session III # 89, Tuesday Morning