ERUS 2018: Intraoperative Frozen Section of the Dorsal Vein for Prediction of Anterior Extracapsular Extension after Robotic-Assisted Radical Prostatectomy

Marseille, France ( Dr. Wong presented a study on the utilization of intraoperative frozen section of the dorsal vein for the prediction of anterior extracapsular extension (ECE) in robotic radical prostatectomy (RALP).

The study took place between 2007 and 2016. A total of 141 patients who underwent RALP had intraoperative froze section of the dorsal vein. Tumor location of these patients was divided into six different regions (apex, mid base) and anterior and posterior. Multiparametric MRI results and pathologic results were compared. Baseline characteristics are demonstrated in table 1, and the accuracy of the MRI results are shown in table 2.

UroToday ERUS2018 Baseline characteristics
Table 1 – Baseline characteristics

UroToday ERUS2018 Accuracy of the MRI results
Table 2 – Accuracy of the MRI results

Logistic regression analysis demonstrated that positive frozen dorsal vein, MRI showing anterior ECE, and initial PSA were all predictors of anterior ECE. Furthermore, logistic regression analysis also demonstrated that Pathologic Gleason score of 8 or more (compared to 7 or less), the percentage of tumor volume, the presence of lymphovascular invasion, initial PSA, and anterior prostate ECE were all predictors of a positive frozen dorsal vein.

The authors concluded that anterior ECE was associated with the positive dorsal vein frozen section. Therefore, if the frozen section of the dorsal vein is positive, wide excision of the anterior prostate is warranted to avoid positive surgical margins.

The study has a statistical flaw that the logistic regression model predicting positive frozen dorsal vein section had eight variables, and the number of events was only 10. Therefore, the number of variables in the model is too high. Despite this, the presented study is quite novel, and it won an award for best poster at the ERUS 2018 meeting.

Presented by: W. Song, Seoul, South Korea

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre, Twitter:@GoldbergHanan at the EAU Robotic Urology Section (ERUS) Meeting - September 5 - 7, 2018 - Marseille, France