Assessing the extirpative quality of a radical prostatectomy technique: categorisation and mapping of technical errors

Objective To examine the extirpative quality of an open radical prostatectomy (RP) technique by first categorising and mapping all intraprostatic incisions into benign tissue and then determining a cumulative technical error rate given by all intraprostatic incisions into benign and malignant tissue. Patients and Methods We performed a retrospective review of prospectively collected data relating to 1065 men with clinically localised prostate cancer who underwent open retropubic RP (70.6% nerve-sparing surgery [NSS]) by a single surgeon (January 2005 to December 2011). We recorded all intraprostatic incisions: (i) iatrogenic positive surgical margins (PSMs), (ii) deep or superficial benign capsular incisions (BCIs), (iii) incisions into benign prostate glands at the prostate apex or bladder neck (benign glandular tissue incisions [BGTIs]), and determined incision location, length and nature (solitary/multiple). We evaluated: (i) associations between benign incisions, NSS and PSMs, (ii) significant predictors for PSM risk by multivariate analysis, (iii) postoperative biochemical recurrence (BCR)-free survival (Kaplan–Meier method). Results Intraprostatic incision rates were 2.3% pT2 PSMs, 6.0% BCIs and 5.4% BGTIs. There were slight variations in rate over time and with NSS technique. Benign incisions were located as follows: 46.8% right posterolateral, 37.5% left posterolateral, and 15.7% bilateral for BCIs; 58.6% bladder neck and 41.4% apical for BGTIs. The median (range) incision length, for solitary and multiple incisions respectively, was 4 (1–13) and 9 (2–25) mm for BCIs and 1 (1–5) and 2 (2–6) mm for BGTIs. BCI rate, but not BGTI rate, was significantly associated with NSS (P = 0.004) and PSM (P = 0.005), and increased PSM risk 3.6-fold. A PSM increased BCR risk two-fold (odds ratio 2.078, 95% confidence interval 1.383–3.122). BCR-free survival decreased significantly even for short PSMs (<1 mm; P < 0.001). Conclusions Although the pT2 PSM rate was low (2.3%), the cumulative technical error rate (patients with at least one pT2 PSM, BCI or BGTI) was five-fold higher (12.5%). Categorising and mapping intraprostatic incisions is a tool surgeons can use in self-audits to identify areas of potential improvement, reduce errors, and improve surgical skills.