Evaluation of image-based prognostic parameters of post-prostatectomy urinary incontinence: A literature review

Integrating clinical and image-based parameters for prediction of early post-prostatectomy incontinence recovery: simplified nomogram approach

PURPOSE

This study aimed to develop a novel model that combines both clinical and image-based parameters to predict early recovery of urinary incontinence after robotic-assisted radical prostatectomy (RARP) more easily and precisely.

MATERIALS AND METHODS

We retrospectively enrolled data from patients who underwent RARP performed by a single surgeon. Clinical parameters were collected through medical chart review. All patients received cystography one week after RARP to evaluate the anastomosis healing condition. All cystography images were analyzed by a single radiologist who was blinded to the clinical status of the patients. Multivariate analysis was performed to select significant predictors for early post-prostatectomy incontinence (PPI) recovery, defined as being pad-free within four weeks after surgery.

RESULTS

A total of 293 patients were enrolled in this study. Among them, 26.7% experienced immediate dryness after surgery, while 47.6% achieved being pad-free within one month. The overall continence rate was over 90% six months after surgery. In univariate analysis, factors associated with early PPI recovery were BMI, T stage, NVB preservation, surgical margin status, downward bladder neck, and bladder neck angle on cystography. BMI, NVB preservation, and downward bladder neck remained significant in multivariate analysis (p-values = 0.041, 0.027, and 0.023, respectively). A nomogram model was established based on these three predictors.

CONCLUSION

This is the first model to combine preoperative clinical factors, peri-surgical factors, and postoperative image-based factors to predict PPI recovery after RARP. This model can assist clinicians in taking optimal actions for PPI and also reduce patient anxiety.

The predictors of short and long term urinary continence recovery after laparoscopic radical prostatectomy: a single cancer center report in China

PURPOSE

To evaluate the predictors for short and long term urinary continence (UC) recovery after laparoscopic radical prostatectomy (LRP) from clinical and oncological variables.

METHODS

We retrospectively collected data from 142 prostate cancer patients who underwent LRP between September 2014 and June 2021 at a tumor specialist diagnosis and treatment center in China. The rate of post-prostatectomy incontinence (PPI) was evaluated from immediate and at 3, 6 and 12 mo after LRP, and UC was defined as the use of no or one safety pad. Sixteen clinical and oncological variables were analyzed by univariate and multivariate regression analysis to determine whether they were associated with short (3 mo) or long term (12 mo) UC recovery after LRP.

RESULTS

After eliminating patients who were lost to follow-up, 129 patients were eventually included. The mean ± SD age was 68 ± 6.3 years. The UC rates of immediate, 3, 6 and 12 mo after the operation were 27.9%, 54.3%, 75.2% and 88.4%, respectively. Multivariate analyses revealed that membranous urethral length (MUL) was a protective predictor of UC after catheter extraction(P < 0.001), and at 3 mo (P < 0.001), 6 mo (P < 0.001) and 12 mo (P = 0.009) after surgery.

CONCLUSION

MUL is a significant independent factor that can contribute to short and long term UC recovery post-LRP, which may assist clinicians and their patients in counseling of treatment.

Detection of intraductal carcinoma in prostate cancer patients with small tumor volume

OBJECTIVES

The purpose of this study was to investigate intraductal carcinoma of the prostate (intraductal carcinoma) and significant cancer (SC) in patients with small tumor volume (<0.5 cm³ ) in prostatectomy specimens.

METHODS

Data from 639 patients undergoing radical prostatectomy between April 2006 and December 2017 at Chiba University Hospital and 2 affiliated institutions were retrospectively reviewed. Tumor volume in prostatectomy specimens was measured, and with a tumor volume of less than 0.5 cm³ , the presence of intraductal carcinoma and SC was examined. SC was defined as one that did not meet the definition of pathological insignificant cancer (organ-confined cancer, Grade Group 1, tumor volume < 0.5 cm³ ). The number of patients who met four active surveillance (AS) protocols was also examined.

RESULTS

A total of 83 patients with tumor volume < 0.5 cm³ were identified in this study population (SC: 43 patients [52%], intraductal carcinoma: 5 patients [6%]). The median follow-up was 34.6 months (range: 18-57 months). Four (5%) developed biochemical recurrence. The number of positive biopsy cores ≥ 2 was an independent predictor of SC in patients with tumor volume < 0.5 cm³ (hazard ratio: 4.39; 95% confidence interval: 1.67-11.56; p = 0.003). In tumor volume < 0.5 cm³ , tumor volume was significantly correlated with the International Society of Urological Pathology Grade Group (1 vs. 4-5, p = 0.002) and the presence of intraductal carcinoma (p = 0.004). In intraductal carcinoma-positive cases, four of five patients (80%) had the predictor of SC, which was two or more positive biopsy cores. Of the four AS protocols, the criteria for Prostate Cancer Research International: Active Surveillance were met most frequently in 46 cases (55%) of tumor volume less than 0.5 cm³ if targeted biopsy by magnetic resonance imaging was available.

CONCLUSION

The results of the present study suggest that intraductal carcinoma was present even in cases with small tumor volumes. Grade Group and intraductal carcinoma showed a positive correlation with tumor volume.

Inter-observer variability in male pelvic-floor MRI measurements that might predict post-prostatectomy incontinence

INTRODUCTION

Current studies are focusing on the relationship between anatomical variables in preoperative prostate MRI and the development of post-prostatectomy incontinence (PPI). Nevertheless, there is little evidence regarding the reliability of these measurements. The objective of this study was to analyze the concordance between urologists and radiologists for anatomical measurements that might be PPI predictors.

MATERIAL AND METHODS

Pelvic floor measurements with 3T-MRI were performed by two radiologists and two urologists independently and blindly. Interobserver agreement was determined using the intraclass correlation coefficient (ICC) and the Bland-Altman plot.

RESULTS

The concordance was good-acceptable for most measurements, except for the levator ani and puborectalis muscle thickness (some ICC values  < 0.20/p value > 0.05). The anatomical parameters with the highest degree of agreement were intravesical prostatic protrusion (IPP) and prostate volume (most of the ICC values > 0.60). The membranous urethral length (MUL) and the angle of the membranous urethra-prostate axis (aLUMP) presented ICC > 0.40. The obturator internus muscle thickness (OIT), urethral width and intraprostatic urethral length presented a fair-moderate degree of agreement (ICC > 0.20). Regarding the agreement between different specialists, the highest degree was obtained for the two radiologists and for urologist 1-radiologist 2 (moderate median agreement), while urologist 2 with each of the radiologists had a regular median agreement.

CONCLUSIONS

MUL, IPP, prostate volume, aLUMP, OIT, urethral width and prostatic length show acceptable inter-observer concordance and they would be reliable as possible predictors of PPI. Levator ani and puborectalis muscle thickness show bad agreement. Interobserver agreement might not be greatly influenced by previous professional experience.

Recognition of Postoperative Cystography Features by Artificial Intelligence to Predict Recovery from Postprostatectomy Urinary Incontinence: A Rapid and Easy Way to Predict Functional Outcome

Purpose: Post-operative cystography has been used to predict the recovery of postprostatectomy urinary incontinence (PPI) in patients with localized prostate cancer. This study aimed to validate the predictive value of cystography for PPI and utilize a deep learning model to identify favorable and unfavorable features. Methods: Medical records and cystography images of patients who underwent robotic-assisted radical prostatectomy for localized prostate cancer were retrospectively reviewed. Specific cystography features, including anastomosis leakage, a downward bladder neck (BN), and the bladder neck angle, were analyzed for the prediction of PPI recovery. Favorable and unfavorable patterns were categorized based on the three cystography features. The deep learning model used for transfer learning was ResNet 50 and weights were trained on ImageNet. We used 5-fold cross-validation to reduce bias. After each fold, we used a test set to confirm the model’s performance. Result: A total of 170 consecutive patients were included; 31.2% experienced immediate urinary continence after surgery, while 93.5% achieved a pad-free status and 6.5% were still incontinent in the 24 weeks after surgery. We divided patients into a fast recovery group (≤4 weeks) and a slow recovery group (>4 weeks). Compared with the slow recovery group, the fast recovery group had a significantly lower anastomosis leakage rate, less of a downward bladder neck, and a larger bladder neck angle. Test data used to evaluate the model’s performance demonstrated an average 5-fold accuracy, sensitivity, and specificity of 93.75%, 87.5%, and 100%, respectively. Conclusions: Postoperative cystography features can predict PPI recovery in patients with localized prostate cancer. A deep-learning model can facilitate the identification process. Further validation and exploration are required for the future development of artificial intelligence (AI) in this field.

Transperineal Ultrasound Before and After Prostatectomy: Technical Approach and Description

This study assessed the feasibility of dynamic transperineal ultrasound (TPUS) pre/post-radical prostatectomy (RP). Ninety-eight patients were scanned pre-operatively and at four time-points post-operatively. TPUS was performed in 98 patients using an abdominal transducer at rest, during pelvic floor contraction (PFC) and Valsalva (VS) maneuver in supine and standing positions. Urodynamic evaluations included bladder neck angle at rest/PFC/VS, and degree of bladder neck movement. Pre-operative and post-operative measurements were technically feasible in >85% (supine) and >90% (standing) of patients. TPUS offers a reliable non-invasive dynamic assessment of the pelvic floor post-prostatectomy and may prove a useful adjunct for guiding exercises to preserve continence.

Value of Different Magnetic Resonance Imaging-based Measurements of Anatomical Structures on Preoperative Prostate Imaging in Predicting Urinary Continence After Radical Prostatectomy in Men with Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

Measurements of anatomical structures on preoperative prostate magnetic resonance imaging (MRI) are used in risk models for treatment decisions to predict urinary continence (UC) following radical prostatectomy (RP). However, the association between these parameters and UC is unclear.

OBJECTIVE

To systematically summarize the literature on prognostic preoperative prostate MRI measurements of (peri)prostatic structures in relation to time to recovery of postoperative UC in men with prostate cancer.

EVIDENCE ACQUISITION

Online libraries were searched up to August 27, 2021. Article selection and critical appraisal were performed by two reviewers. All papers reporting on preoperative MRI measurements with UC correlation in univariable or multivariable analyses were included.

EVIDENCE SYNTHESIS

In the 50 studies included (mostly retrospective), 57 MRI parameters were evaluated. The pooled analyses showed that greater membranous urethra length (MUL) was prognostic for regaining UC at 1 mo (odds ratio [OR] 1.15, 95% confidence interval [CI] 1.10-1.21), 3 mo (OR 1.23, 95% CI 1.16-1.31), 6 mo (OR 1.16, 95% CI 1.08-1.25), and 12 mo (OR 1.19, 95% CI 1.10-1.29). Several other anatomical structures showed at least in one study a significant correlation with later return to UC: four prostate-related parameters (greater depth, apical protrusion, larger intravesical protrusion, small dorsal vascular complex), five urethra-related parameters (thicker wall, severe fibrosis, smaller volume, larger preoperative angle between the prostate axis and membranous urethra, shorter minimal residual MUL), and six musculoskeletal-related parameters (lower perfusion ratio, thinner levator ani muscle, larger inner or outer levator distance, shorter pelvic diaphragm length, and larger midpelvic area).

CONCLUSIONS

Greater MUL as measured on preoperative MRI was an independent prognostic factor for return to UC within 1 mo after RP and remained prognostic at 12 mo. Other anatomical structures may potentially be predictive, but these would need to be substantiated in prospective trials before being adopted in postoperative UC risk models for treatment decisions in men with prostate cancer.

PATIENT SUMMARY

We summarized study data on the relation between measurements of anatomical structures on preoperative magnetic resonance imaging scans and urinary continence after removal of the prostate. Greater length of one part of the urethra (membranous urethra) is associated with faster return to continence. Other anatomical structures have potential for predicting postoperative continence, but need further investigation.

Urethral Sphincter Length but Not Prostatic Apex Shape in Preoperative MRI Is Associated with Mid-Term Continence Rates after Radical Prostatectomy

Background: To test the impact of urethral sphincter length (USL) and anatomic variants of prostatic apex (Lee-type classification) in preoperative multiparametric magnet resonance imaging (mpMRI) on mid-term continence in prostate cancer patients treated with radical prostatectomy (RP). Methods: We relied on an institutional tertiary-care database to identify patients who underwent RP between 03/2018 and 12/2019 with preoperative mpMRI and data available on mid-term (>6 months post-surgery) urinary continence, defined as usage 0/1 (-safety) pad/24 h. Univariable and multivariable logistic regression models were fitted to test for predictor status of USL and prostatic apex variants, defined in mpMRI measurements. Results: Of 68 eligible patients, rate of mid-term urinary continence was 81% (n = 55). Median coronal (15.1 vs. 12.5 mm) and sagittal (15.4 vs. 11.1 mm) USL were longer in patients reporting urinary continence in mid-term follow-up (both p < 0.01). No difference was recorded for prostatic apex variants distribution (Lee-type) between continent vs. incontinent patients (p = 0.4). In separate multivariable logistic regression models, coronal (odds ratio (OR): 1.35) and sagittal (OR: 1.67) USL, but not Lee-type, were independent predictors for mid-term continence. Conclusion: USL, but not apex anatomy, in preoperative mpMRI was associated with higher rates of urinary continence at mid-term follow-up.