Apical Surgical Margins Status in Robot-Assisted Laparoscopic Radical Prostatectomy Does Not Depend on Disease Characteristics

Integration of Multiparameter MRI into Conventional Pretreatment Risk Factors to Predict Positive Surgical Margins After Radical Prostatectomy

INTRODUCTION/BACKGROUND

Positive surgical margins (PSMs) after radical prostatectomy (RP) can increase the risk of biochemical recurrence in prostate cancer (PCa) patients. However, the prediction of the likelihood of PSMs in patients undergoing similar surgical procedures remains a challenge. We aim to develop a predictive model for PSMs in patients undergoing non-nerve-sparing RP.

PATIENTS AND METHODS

In this retrospective study, we analyzed data from PCa patients who underwent minimally invasive non-nerve-sparing RP at our hospital between June 2017 and June 2021. We identified independent risk factors associated with PSMs using clinical and MRI-based parameters in univariate and multivariate logistic regression analyzes. These factors were then used to develop a nomogram for predicting the probability of PSMs. The predictive performance was validated using calibration and receiver operating characteristic curve, area under the curve ,and decision curve analysis.

RESULTS

Multivariate analyzes revealed prostate-specific antigen density, tumor size, tumor location at the apex, tumor contact length, extracapsular extension (ECE) level, and apparent diffusion coefficient value as independent risk factors. A nomogram was developed and validated with high accuracy (C-index = 0.78). Furthermore, we found that 44.2% of patients diagnosed with organ-confined disease had ECE after surgery, and 29.1% of patients with Gleason scores ≤7 had higher pathological scores. Interestingly, the tumor burden calculated from PCa biopsy cores was overestimated when compared to postoperative PCa specimens.

CONCLUSION

We developed a reliable nomogram for predicting the risk of PSMs in PCa patients undergoing non-nerve-sparing RP. The study highlights the importance of incorporating these parameters in personalized surgical management.

Clinical outcomes for men with positive surgical margins after radical prostatectomy-results from the South Australian Prostate Cancer Clinical Outcomes Collaborative community-based registry

Objective

Positive surgical margins (PSMs) after radical prostatectomy (RP) indicate failure of surgery to completely clear cancer. PSMs confer an increased risk of biochemical recurrence (BCR), but how more robust outcomes are affected is unclear. This study investigated factors associated with PSMs following RP and determined their impact on clinical outcomes (BCR, second treatment [radiotherapy and/or androgen deprivation therapy], and prostate cancer-specific mortality [PCSM]).

Methods

The study cohort included men diagnosed with prostate cancer (pT2-3b/N0/M0) between January 1998 and June 2016 who underwent RP from the South Australian Prostate Cancer Clinical Outcomes Collaborative database. Factors associated with risk of PSMs were identified using Poisson regression. The impact of PSMs on clinical outcomes (BCR, second treatment, and PCSM) was assessed using competing risk regression.

Results

Of the 2827 eligible participants, 28% had PSMs-10% apical, 6% bladder neck, 17% posterolateral, and 5% at multiple locations. Median follow-up was 9.6 years with 81 deaths from prostate cancer recorded. Likelihood of PSM increased with higher pathological grade and pathological tumor stage, and greater tumour volume, but decreased with increasing surgeon volume (odds ratio [OR]: 0.93; 95% confidence interval [CI]: 0.88-0.98, per 100 previous prostatectomies). PSMs were associated with increased risk of BCR (adjusted sub-distribution hazard ratio [sHR] 2.5; 95% CI 2.1-3.1) and second treatment (sHR 2.9; 95% CI 2.4-3.5). Risk of BCR was increased similarly for each PSM location, but was higher for multiple margin sites. We found no association between PSMs and PCSM.

Conclusion

Our findings support previous research suggesting that PSMs are not independently associated with PCSM despite strong association with BCR. Reducing PSM rates remains an important objective, given the higher likelihood of secondary treatment with associated comorbidities.

Prediction of a positive surgical margin and biochemical recurrence after robot-assisted radical prostatectomy

The positive surgical margin (PSM) and biochemical recurrence (BCR) are two main factors associated with poor oncotherapeutic outcomes after prostatectomy. This is an Asian population study based on a single-surgeon experience to deeply investigate the predictors for PSM and BCR. We retrospectively included 419 robot-assisted radical prostatectomy cases. The number of PSM cases was 126 (30.1%), stratified as 22 (12.2%) in stage T2 and 103 (43.6%) in stage T3. Preoperative prostate-specific antigen (PSA) > 10 ng/mL (p = 0.047; odds ratio [OR] 1.712), intraoperative blood loss > 200 mL (p = 0.006; OR 4.01), and postoperative pT3 stage (p < 0.001; OR 6.901) were three independent predictors for PSM while PSA > 10 ng/mL (p < 0.015; hazard ratio [HR] 1.8), pT3 stage (p = 0.012; HR 2.264), International Society of Urological Pathology (ISUP) grade > 3 (p = 0.02; HR 1.964), and PSM (p = 0.027; HR 1.725) were four significant predictors for BCR in multivariable analysis. PSMs occurred mostly in the posterolateral regions (73.8%) which were associated with nerve-sparing procedures (p = 0.012) while apical PSMs were correlated intraoperative bleeding (p < 0.001). A high ratio of pT3 stage after RARP in our Asian population-based might surpass the influence of PSM on BCR. PSM was less significant than PSA and ISUP grade for predicting PSA recurrence in pT3 disease. Among PSM cases, unifocal and multifocal positive margins had a similar ratio of the BCR rate (p = 0.172) but ISUP grade > 3 (p = 0.002; HR 2.689) was a significant BCR predictor. These results indicate that PSA and pathological status are key factors influencing PSM and BCR.

Should the involvement of skeletal muscle by prostatic adenocarcinoma be reported on biopsies?

Skeletal muscle is seen at the distal part of the prostate apex, where benign glands may reside as part of normal anatomy and histology, and extends more proximally anteriorly. At times, prostatic adenocarcinoma can be seen admixed with skeletal muscle, raising the question of extraprostatic extension. Although there has been increased attention regarding biopsy sampling of the distal apex to guide the performing of the apical dissection on radical prostatectomy, the finding of skeletal muscle involvement by prostatic adenocarcinoma has not been consistently reported by pathologists on biopsies. We searched our database spanning 12 years from 2000 to 2012 for all patients who had prostatic adenocarcinoma Gleason score 3 + 3 = 6 involving skeletal muscle on biopsy. We identified 220 patients who met the criteria. Of the 220 patients, 101 underwent prostatectomy, which comprised the "study group." Prostatectomy reports from these patients were compared with those of a "control group," which consisted of 201 contemporaneous patients with Gleason score 3 + 3 = 6 prostatic adenocarcinoma on biopsy without skeletal muscle involvement. The results showed a significantly higher percentage of positive margins in the study group compared with the control group (P = .006). The study group also had a higher percentage of positive margins at the apex admixed with skeletal muscle (P = .008). In summary, the findings in this study support that pathologists should report the involvement of skeletal muscle by tumor, and recommend that urologists performing radical prostatectomies on these patients try to ensure adequate excision in the apical area to avoid positive apical margin.

Systematic review of learning curves for minimally invasive abdominal surgery: a review of the methodology of data collection, depiction of outcomes, and statistical analysis

OBJECTIVE

To determine how minimally invasive surgical learning curves are assessed and define an ideal framework for this assessment.

BACKGROUND

Learning curves have implications for training and adoption of new procedures and devices. In 2000, a review of the learning curve literature was done by Ramsay et al and it called for improved reporting and statistical evaluation of learning curves. Since then, a body of literature is emerging on learning curves but the presentation and analysis vary.

METHODS

A systematic search was performed of MEDLINE, EMBASE, ISI Web of Science, ERIC, and the Cochrane Library from 1985 to August 2012. The inclusion criteria are minimally invasive abdominal surgery formally analyzing the learning curve and English language. 592 (11.1%) of the identified studies met the selection criteria.

RESULTS

Time is the most commonly used proxy for the learning curve (508, 86%). Intraoperative outcomes were used in 316 (53%) of the articles, postoperative outcomes in 306 (52%), technical skills in 102 (17%), and patient-oriented outcomes in 38 (6%) articles. Over time, there was evidence of an increase in the relative amount of laparoscopic and robotic studies (P < 0.001) without statistical evidence of a change in the complexity of analysis (P = 0.121).

CONCLUSIONS

Assessment of learning curves is needed to inform surgical training and evaluate new clinical procedures. An ideal analysis would account for the degree of complexity of individual cases and the inherent differences between surgeons. There is no single proxy that best represents the success of surgery, and hence multiple outcomes should be collected.

EAU guidelines on robotic and single-site surgery in urology

CONTEXT

This is a short version of the European Association of Urology (EAU) guidelines on robotic and single-site surgery in urology, as created in 2013 by the EAU Guidelines Office Panel on Urological Technologies.

OBJECTIVE

To evaluate current evidence regarding robotic and single-site surgery in urology and to provide clinical recommendations.

EVIDENCE ACQUISITION

A comprehensive online systematic search of the literature according to Cochrane recommendations was performed in July 2012, identifying data from 1990 to 2012 regarding robotic and single-site surgery in urology.

EVIDENCE SYNTHESIS

There is a lack of high-quality data on both robotic and single-site surgery for most upper and lower urinary tract operations. Mature evidence including midterm follow-up data exists only for robot-assisted radical prostatectomy. In the absence of high-quality data, the guidelines panel's recommendations were based mostly on the review of low-level evidence and expert opinions.

CONCLUSIONS

Robot-assisted urologic surgery is an emerging and safe technology for most urologic operations. Further documentation including long-term oncologic and functional outcomes is deemed necessary before definite conclusions can be drawn regarding the superiority or not of robotic assistance compared with the conventional laparoscopic and open approaches. Laparoendoscopic single-site surgery is a novel laparoscopic technique providing a potentially superior cosmetic outcome over conventional laparoscopy. Nevertheless, further advantages offered by this technology are still under discussion and not yet proven. Due to the technically demanding character of the single-site approach, only experienced laparoscopic surgeons should attempt this technique in clinical settings.

PATIENT SUMMARY

This work represents the shortened version of the 2013 European Association of Urology guidelines on robotic and single-site surgery. The authors systematically evaluated published evidence in these fields and concluded that robotic assisted surgery is possible and safe for most urologic operations. Whilst laparoendoscopic single-site surgery is performed using the fewest incisions, the balance between risk and benefit is currently unclear. The evidence to support the conclusions in this guideline was generally poor, but best for robotic assisted radical prostatectomy. As such, these recommendations were based upon expert opinion, and further high-quality research is needed in this field.