Intraoperative T staging in radical retropubic prostatectomy: is it reliable?

During radical prostatectomy, wide local excision of the lateral prostatic fascia and neurovascular bundle on the ipsilateral side of the tumor is advocated if nerve sparing is likely to result in a positive surgical margin. Our intent was to validate whether intraoperative T staging can predict the presence of positive surgical margins and aid in the decision of whether to perform nerve-sparing prostatectomy.

One surgeon performed 100 consecutive radical prostatectomies, and one pathologist interpreted the pathologic findings. Topographic distribution of tumor within the specimen was assessed intraoperatively by palpation. The margin status was similarly assessed. This tactile clinical impression was compared with the final pathologic findings.

The surgical margins were positive in 39 (39%) of 100 cases. The intraoperative assessment of the margin status had a high false-negative rate and a sensitivity of only 7%. However, the specificity was 96%, because few margins were falsely positive. The overall accuracy was 62%, with a negative predictive value of 62%. The sensitivity of the intraoperative assessment of tumor location was 73%, and the positive predictive value was 65%.

The results of our study indicate that the intraoperative assessment of the margin status is not accurate and thus cannot help determine which patients require excision of the neurovascular bundle. We believe the decision to preserve the neurovascular bundle should be based on the preoperative prognostic factors and the presence of an intact capsule covering the region of the gland adjacent to this structure.