Clinical factors affecting perioperative outcomes in robot-assisted radical prostatectomy

High-volume surgeons decrease operating time in robot-assisted radical prostatectomy: results in 1229 patients

BACKGROUND

The aim is to evaluate factors impacting operating time (OT) during robot-assisted radical prostatectomy (RARP) with or without extended pelvic lymph node dissection (ePLND) for prostate cancer.

METHODS

Overall, 1289 patients underwent RARP from January 2013 to December 2021. ePLND was performed in 825 cases. Factors potentially associated with OT variations were assessed. Three low-volume (LVS) and two high-volume surgeons (HVS) performed the procedures. A linear regression model was computed to assess associations with OT variations.

RESULTS

When RARP was performed by HVS an OT decrease was observed independently by significant clinical (Body Mass Index [BMI]; prostate volume [PV]) and anatomical/perioperative features (prostate weight [PW]; intraoperative blood loss [BL]) both in clinical (change in OT: -42.979 minutes; 95% CI: -51.789; -34.169; P<0.0001) and anatomical/perioperative models (change in OT: -40.020 minutes; 95% CI: -48.494; -31.587; P<0.0001). A decreased OT was observed in clinical (change in OT: -27.656 minutes; 95% CI: -33.449; -21.864; P<0.0001) and anatomical/perioperative (change in OT: -24.935 minutes; 95% CI: -30.562; -19.308; P<0.0001) models also in case of RARP with ePLND performed by HVS, independently by BMI, PV, PSA as well as for PW, seminal vesicle invasion, positive surgical margins, and BL.

CONCLUSIONS

In a tertiary academic referral center, OT decreased when RARP was performed by HVS, independently of adverse clinical and anatomical/perioperative factors. Available OT loads can be planned to optimize waiting lists, teaching tasks, operative costs, and surgeon's volume.

Novel nomogram to predict biochemical recurrence-free survival after radical prostatectomy

PURPOSE

Conditional survival represents the probability of subsequent survival given that patients have already survived a certain length of time. Several models predict biochemical recurrence (BCR) after radical prostatectomy. However, none of them include postoperative prostate-specific antigen (PSA). We aimed to analyze BCR-free survival evolution over time and develop a nomogram incorporating the postoperative PSA value to predict BCR-free survival.

MATERIAL AND METHODS

We included patients treated with robot-assisted radical prostatectomy (RARP) for prostate cancer between 2009 and 2021 and calculated conditional survival. Cox proportional hazard regression analysis was used to assess the predictive variables of BCR. We developed a nomogram predicting BCR-free survival three and five years after RARP. We used c-index and decision curve analyses to compare the nomogram with the Cancer of the Prostate Risk Assessment post-Surgical (CAPRA-S) score.

RESULTS

We included 718 patients. The overall 3- and 5-year BCR-free survival rates were 85.1% and 75.7%, respectively. The 5-year BCR-free survival rates increased to 78.9%, 82.9%, 85.2%, and 84.7% for patients surviving 1, 2, 3, and 4 years without BCR, respectively. We developed a nomogram including the pathological Gleason score and T stage, positive surgical margin, PSA ≥ 0.05 ng/mL at one year, and lymph node involvement to predict BCR at 3 and 5 years postoperatively. Our nomogram presented a higher c-index (0.89) than the CAPRA-S score (0.78; p = 0.001) and a positive net benefit at 3 and 5 years postoperatively in the decision curve analyses.

CONCLUSION

The 5-year conditional BCR-free survival increased with survival without BCR. The developed nomogram significantly improved the accuracy in predicting BCR-free survival after RARP.

The 'prostate-muscle index': a simple pelvic cavity measurement predicting estimated blood loss and console time in robot-assisted radical prostatectomy

This study was to show the impact of ‘prostate-muscle index (PMI)’, which we developed as a novel pelvic cavity measurement, in patients undergoing robot-assisted radical prostatectomy (RARP). We defined PMI as the ‘distance between the inner edge of the obturator internus muscle and the lateral edge of the prostate at the magnetic resonance imaging (MRI) slice showing the maximum width of the prostate’. Seven hundred sixty patients underwent RARP at the University of Tokyo Hospital from November 2011 to December 2018. MRI results were unavailable in 111 patients. In total, 649 patients were eligible for this study. Median values of blood loss and console time were 300 mL and 168 min. In multivariate analysis, body mass index (BMI), prostate volume-to-pelvic cavity index (PV-to-PCI), PMI, and surgical experience were significantly associated with blood loss > 300 mL (P = 0.0002, 0.002, < 0.0001, and 0.006 respectively). Additionally, BMI, PMI, and surgical experience were also significantly associated with console time > 160 min in multivariate analysis (P = 0.04, 0.004, and < 0.0001, respectively). In conclusion, PMI may provide useful information to surgeons and patients in preoperative decision-making.

The Effect of Adverse Patient Characteristics on Perioperative Outcomes in Open and Robot-Assisted Radical Prostatectomy

Objective: To analyze the effect of adverse preoperative patient and tumor characteristics on perioperative outcomes of open (ORP) and robot-assisted radical prostatectomy (RARP).

Material and Methods: We retrospectively analyzed 656 patients who underwent ORP or RARP according to intraoperative blood loss (BL), operation time (OR time), neurovascular bundle preservation (NVBP) and positive surgical margins (PSM). Univariable and multivariable logistic regression models were used to identify risk factors for impaired perioperative outcomes.

Results: Of all included 619 patients, median age was 66 years. BMI (<25 vs. 25-30 vs. ≥30) had no influence on blood loss. Prostate size >40cc recorded increased BL compared to prostate size ≤ 40cc in patients undergoing ORP (800 vs. 1200 ml, p < 0.001), but not in patients undergoing RARP (300 vs. 300 ml, p = 0.2). Similarly, longer OR time was observed for ORP in prostates >40cc, but not for RARP. Overweight (BMI 25-30) and obese ORP patients (BMI ≥30) showed longer OR time compared to normal weight (BMI <25). Only obese patients, who underwent RARP showed longer OR time compared to normal weight. NVBP was less frequent in obese patients, who underwent ORP, relative to normal weight (25.8% vs. 14.0%, p < 0.01). BMI did not affect NVPB at RARP. No differences in PSM were recorded according to prostate volume or BMI in ORP or RARP. In multivariable analyses, patient characteristics such as prostate volume and BMI was an independent predictor for prolonged OR time. Moreover, tumor characteristics (stage and grade) predicted worse perioperative outcome.

Conclusion: Patients with larger prostates and obese patients undergoing ORP are at risk of higher BL, OR time or non-nervesparing procedure. Conversely, in patients undergoing RARP only obesity is associated with increased OR time. Patients with larger prostates or increased BMI might benefit most from RARP compared to ORP.