The surface frozen section technique is associated with a low false-negative surgical margin rate. It might allow for safer preservation of functional anatomical structures in misclassified patients or even patients at higher preoperative risk.

Objectives We sought to evaluate the ethnic variation in pelvimetry and its impact as a predictor of positive surgical margins (PSM) at radical prostatectomy (RP). Methods Preoperative MRI was performed in 482 Caucasian and 103 African-American (AA) men undergoing RP without prior treatment from 07/03-01/05 and 11/01-06/07, respectively. We measured bony and soft tissue dimensions on MRI to evaluate the pelvic inlet, midplane, prostate size and apical depth. Analysis of covariance was performed to determine the effect of ethnicity on the midpelvic area (MPA). We performed multivariate logistic regression analysis for prediction of overall and site-specific PSM. Results AA men had a significantly steeper symphysis pubis angle (median 43.1° vs 41.3°, respectively, p=0.001) and smaller MPA (median 78.5 vs 83.9 cm2, respectively, p=0.004). Ethnicity and BMI were found to have a significant effect on MPA. Apical depth of the prostate was identified as a significant independent predictor of apical PSM with a more pronounced effect in AA men. Pelvimetric measures were not a significant predictor of other sites of PSM. Conclusions AA men have a significantly smaller MPA and steeper symphysis angle. The adverse impact of a deep pelvis, as measured by the apical prostatic depth, on apical PSM was found to be greater in AA men. Evaluation of pelvic dimensions and prostate parameters in preoperative MRI imaging may add to our understanding of their impact on surgical outcomes.

Study Type – Therapy (case series)
Level of Evidence 4 OBJECTIVE To determine the effect of a deep and narrow pelvis on apical positive surgical margins (PSM) at radical prostatectomy (RP), controlling for other clinical and pathological variables and surgical approach, i.e. open retropubic (RRP) vs laparoscopic (LRP), as apical dissection is expected to be more challenging at RP with a prostate situated deep in a narrow pelvis. PATIENTS AND METHODS From July 2003 to January 2005, 512 consecutive patients with preoperative prostate magnetic resonance imaging (MRI) underwent RRP or LRP with no previous radio‐ or hormonal therapy. An additional 74 patients with preoperative MRI undergoing RP from December 2001 to June 2007 who had an apical PSM were also included, with 586 patients comprising the study population. Bony and soft‐tissue pelvic dimensions, including interspinous distance (ISD), bony (BFW) and soft tissue (SW) pelvic width, apical prostate depth (AD) and symphysis pubis angle, were measured on preoperative MRI. The pelvic dimension index (PDI), bony width index (BWI) and soft‐tissue width index (SWI) were defined as ISD/AD, BFW/AD and SW/AD, respectively. Multivariate logistic regression was used to assess the effect of pelvic dimensions on apical PSM, controlling for surgical approach and clinical and pathological variables. RESULTS There was no significant difference in ISD, BFW, SW or symphysis angle between patients with and without apical PSM. The AD was significantly greater in men with an apical PSM and consequently PDI, BWI and SWI were significantly lower in men with an apical PSM. Each of PDI, AD, BWI and SWI was a significant independent predictor of apical PSM, independent of surgical approach, and other clinicopathological variables. The main limitations of the study were that it was retrospective, and the relatively few patients with apical PSM. CONCLUSIONS Apical prostate depth is an independent risk factor for apical PSM at RP. MRI pelvimetry might allow for preoperative planning of the approach to RP.