Total mesorectal excision--does the choice of dissection technique have an impact on pelvic autonomic nerve preservation?

Comparison of postoperative laparoscopic and open total mesorectal excision on lower urinary tract function in men with rectal cancer

OBJECTIVES

This study investigated male voiding dysfunction (VD) or lower urinary tract function in rectal cancer (RC) patients after laparoscopic or open total mesorectal excision with pelvic autonomic nerve preservation (PANP).

METHODS

One hundred and eighty-seven male RC patients admitted between January 2016 and May 2019 were enrolled in this study, 112 of whom underwent laparoscopic total mesorectal excision (LTME) and 75 underwent open total mesorectal excision (OTME). The International Prostatic Symptom Score (IPSS) was compared between the two groups.

RESULTS

The postoperative IPSS in patients with RC was elevated on day 7 and gradually decreased during the first month after surgery. Compared with the OTME group, the IPSS scores decreased less in the LTME group at week 1, and months 1 and 3 postoperatively (6.82 ± 2.13 vs 10.15 ± 3.86, 5.70 ± 2.45 vs 7.21 ± 2.0, and 5.01 ± 2.09 vs 5.75 ± 2.55, respectively; P < 0.05). The VD rate was significantly lower in the LTME group than the OTME group at 1, 2, and 3 weeks postoperatively (21.4% vs 26.8%,13.4% vs 25.3%, and 9.8% vs18.6%, respectively; P < 0.05); however, there was no major difference in the incidence of VD 6 months postoperatively between the two groups (P > 0.05). VD was more frequent in the OTME group than the LTME group 6 months postoperatively, but the difference was not statistically significant (odds ratio = 1.857, 95% CI, 0.964-3.645, P = 0.064).

CONCLUSIONS

LTME may be superior to OTME with respect to PANP of lower urinary tract function in males with RC.

Identification of the surgical indication line for the Denonvilliers' fascia and its anatomy in patients with rectal cancer

Background

The high rate of urogenital dysfunction after traditional total mesorectal excision (TME) has caused doubts among scholars on the standard fashion of dissection. We have proposed the necessity to preserve the Denonvilliers’ fascia in patients with rectal cancer. However, how to accurately locate the Denonvilliers’ fascia is unclear. This study aimed to explore anatomical features of the Denonvilliers’ fascia by comparing autopsy findings and observations of surgical videos so as to propose a dissection method for the preservation of pelvic autonomic nerves during rectal cancer surgery.

Methods

Five adult male cadaver specimens were dissected, and surgical videos of 135 patients who underwent TME for mid‐low rectal cancer between January 2009 and February 2019 were reviewed to identify and compare the structure of the Denonvilliers’ fascia.

Results

The monolayer structure of the Denonvilliers’ fascia was observed in 5 male cadaver specimens, and it was located between the rectum, the bottom of the bladder, the seminal vesicles, the vas deferens, and the prostate. The Denonvilliers’ fascia was originated from the rectovesical pouch (or rectum‐uterus pouch), down to fuse caudally with the rectourethral muscle at the apex of the prostate, and fused to the lateral ligaments on both sides. The fascia was thinner on the midline with a thickness of 1.06 ± 0.10 mm. The crown shape of the Denonvilliers’ fascia was slightly triangular, with a height of approximately 5.42 ± 0.16 cm at midline. Nerves were more densely distributed in front of the Denonvilliers’ fascia than behind, especially on both sides of it. Under laparoscopic view, the Denonvilliers’ fascia was originated at the lowest point of the rectovesical pouch (or rectum‐uterus pouch), with a thickened white line which was a good mark for identifying the Denonvilliers’ fascia.

Conclusion

Identification of the surgical indication line for the Denonvilliers’ fascia could help us identify the Denonvilliers’ fascia, and it would improve our ability to protect the pelvic autonomic function of patients undergoing TME for rectal cancer.

Preservation of Denonvilliers' fascia for nerve-sparing laparoscopic total mesorectal excision: A neuro-histological study

Urogenital complications due to pelvic autonomic nerve damage frequently occur following rectal surgery. We investigated whether total mesorectal excision (TME) with preservation of the Denonvilliers' fascia (DVF) can effectively prevent the removal of pelvic autonomic nerves through microscopy. Twenty consecutive male patients with mid-low rectal cancer who received TME with preservation or resection of the Denonvilliers' fascia (P and R groups, respectively) were included. Serial transverse sections from surgical specimens were studied histologically. Nerve fibers at the surfaces of the mesorectum were counted. Clinical correlation between the amount of nerve fibers removed and post-operative sexual function was analyzed. Nerve fibers closely localized to the DVF in the R group displaying rich erectile activity (positive anti-nNOS immunostaining). At the anterior surface of the mesorectum, the mean numbers of nNOS-positive nerve fibers per specimen in the P group were significantly lower than the R group (3.0 ± 1.8 vs. 5.0 ± 2.3, P < 0.05). Compared to the R group, patients in the P group had higher IIEF scores and better erectile function at 3 and 6 months post-operatively. The DVF is a key risk zone for pelvic denervation during laparoscopic TME. Preservation of the DVF can prevent the removal of autonomic nerves and protect post-operative erectile function. Clin. Anat. 32:439-445, 2019. © 2019 Wiley Periodicals, Inc.

Pathophysiological aspects of the low anterior resection syndrome for treatment of rectal cancer

The number of patients with bowel dysfunction due to the treatment of rectal cancer has increased during the recent decades. Anatomical and functional disorders after the removal of the rectum are followed by increased stool frequency, urgency, multiple evacuations and flatus or stool incontinence characterizing the low anterior resection syndrome - LARS. The purpose of this article is to present a review of the literature on current concepts and pathophysiological aspects of bowel dysfunction after resection of rectal cancer. It is essential to understand these mechanisms for a better management of patients and recovery of their quality of life.

Effect of preservation of Denonvilliers' fascia during laparoscopic resection for mid-low rectal cancer on protection of male urinary and sexual functions

The aim of this study was to investigate the effect of preservation of Denonvilliers' fascia (DF) during laparoscopic resection for mid-low rectal cancer on protection of male urogenital function. Whether preservation of DF during TME is effective for protection of urogenital function is largely elusive.Seventy-four cases of male mid-low rectal cancer were included. Radical laparoscopic proctectomy was performed, containing 38 cases of preservation of DF (P-group) and 36 cases of resection of DF (R-group) intraoperatively. Intraoperative electrical nerve stimulation (INS) on pelvic autonomic nerve was performed and intravesical pressure was measured manometrically. Urinary function was evaluated by residual urine volume (RUV), International Prostatic Symptom Score (IPSS), and quality of life (QoL). Sexual function was evaluated using the International Index of Erectile Function (IIEF) scale and ejaculation function classification.Compared with performing INS on the surfaces of prostate and seminal vesicles in the R-group, INS on DF in the P-group exhibited higher increasing intravesical pressure (7.3 ± 1.5 vs 5.9 ± 2.4 cmH2O, P = 0.008). In addtion, the P-group exhibited lower RUV (34.3 ± 27.2 vs 57.1 ± 50.7 mL, P = 0.020), lower IPSS and QoL scores (7 days: 6.1 ± 2.4 vs 9.5 ± 5.9, P = 0.002 and 2.2 ± 1.1 vs 2.9 ± 1.1, P = 0.005; 1 month: 5.1 ± 2.4 vs 6.6 ± 2.2, P = 0.006 and 1.6 ± 0.7 vs 2.1 ± 0.6, P = 0.003, respectively), higher IIEF score (3 months: 10.7 ± 2.1 vs 8.9 ± 2.0, P = 0.000; 6 months: 14.8 ± 2.2 vs 12.9 ± 2.2, P = 0.001) and lower incidence of ejaculation dysfunction (3 months: 28.9% vs 52.8%, P = 0.037; 6 months: 18.4% vs 44.4%, P = 0.016) postoperatively.Preservation of DF during laparoscopic resection for selective male mid-low rectal cancer is effective for protection of urogenital function.

Effect of intra-operative autonomic nerve stimulation on pelvic nerve preservation during radical laparoscopic proctectomy

AIM

This study assessed the effect of intra-operative electrical nerve stimulation (INS) on pelvic autonomic nerve preservation (PANP) during laparoscopic resection for rectal cancer.

METHOD

A total of 189 consecutive cases of radical laparoscopic proctectomy were included. PANP was assessed visually or with INS. Urinary function was evaluated by residual urine volume (RUV), International Prostatic Symptom Score (IPSS) and recatheterization rate. Erectile function was evaluated using the International Index of Erectile Function (IIEF-5) scale.

RESULTS

INS successfully confirmed PANP in 65 (91.5%) patients, while direct vision confirmed PANP in only 72 (61.0%) patients. Compared with the successfully confirmed patients, failed patients in the INS group exhibited higher postoperative RUV (100.0 ± 34.6 vs 25.2 ± 13.6 ml, P = 0.003), higher IPSS (7 days, 20.0 ± 8.6 vs 6.5 ± 2.4, P = 0.012; 1 month, 13.5 ± 6.0 vs 5.3 ± 1.9, P = 0.020; 6 months, 11.7 ± 5.1 vs 4.5 ± 1.7, P = 0.018), a greater number of incidences of a micturition disorder (66.7% vs 1.5%, P = 0.000), higher recatheterization rates (33.3% vs 1.5%, P = 0.017) and a lower IIEF score at 3 months (8.25 ± 0.96 vs 10.93 ± 1.99, P = 0.012) and 6 months (12.50 ± 1.29 vs 15.63 ± 1.65, P = 0.001) postoperatively. Compared with the vision group, the INS group had less deterioration in postoperative RUV (31.5 ± 26.4 vs 54.0 ± 46.7 ml, P = 0.000), lower IPSS (7 days, 7.7 ± 5.0 vs 11.0 ± 6.6, P = 0.000; 1 month, 6.0 ± 3.3 vs 7.6 ± 5.4, P = 0.012) and higher IIEF score (3 months, 10.69 ± 2.07 vs 9.42 ± 2.05, P = 0.001; 6 months, 15.36 ± 1.85 vs 13.64 ± 2.00, P = 0.000) as well as a lower incidence of urination disorders (7.0% vs 17.8%, P = 0.038).

CONCLUSION

INS is effective for the accurate evaluation of PANP during radical laparoscopic proctectomy. Combined with INS, laparoscopic proctectomy is more effective in urogenital function protection.

Pathologic processing of the total mesorectal excision

Total mesorectal excision (TME) is the current optimal surgical treatment for patients with rectal carcinoma. A complete TME is related to lower local recurrence rates and increased patient survival. Many confounding factors in the patient's anatomy and prior therapy can make it difficult to obtain a perfect plane, and thus a complete TME. The resection specimen can be thoroughly evaluated, grossly and microscopically, to identify substandard surgical outcomes and increased risk of local recurrence. Complete and accurate data reporting is critical for patient care and helps surgeons improve their technique.

A prospective video-controlled study of genito-urinary disorders in 35 consecutive laparoscopic TMEs for rectal cancer

INTRODUCTION

Genito-urinary disorders (GUD) for radical rectal cancer surgery range from 10 to 30%. In this study, primary endpoint is to prospectively assess their incidence in patients undergoing Laparoscopic Total Mesorectal Excision (LTME) without neoadjuvant chemo-radiation (NCR). Secondary endpoint is to detect the potential lesion site evaluating video-recordings of surgery.

PATIENTS AND METHODS

A study of 35 consecutive patients treated by LTME for extra-peritoneal rectal cancer not subjected to NCR, M:F = 23:12, median age 70, was evaluated preoperatively by Uroflowmetry and US postvoid residual urine measurement (PVR), International Prostatic Symptoms Score (IPSS), and International Consultation on Incontinence Modular Questionnaire (ICIQ) at 1 and 9 months post-operatively. Evaluation of sexual function was carried out by International Index of Erectile Function (IIEF) in males. Data were analyzed performing Fisher and paired samples t tests. Surgical videos of patients affected by GUD were reviewed to identify lesion sites.

RESULTS

Urinary function:IPSS average score: baseline 6.03 ± 5.51, 8.93 ± 6.42 (p = .005) at 1 month, and 7.26 ± 5.55 (p = .041) at 9 months. ICIQ baseline 2.67 ± 5.42, 4.27 ± 6.19 (p = NS) at 1 month, and 3.63 ± 5.23 (p = NS) at 9 months. Maximum urine flow rate baseline 15.95 ± 4.78 ml/s, 14.23 ± 5.27 after 1 month (p = .041), and 15.22 ± 4.01 after 9 months (p = NS). Mean urine flow rate baseline 9.15 ± 2.96 ml/s, 7.99 ± 4.12 ml/s at 1 month (p = .044), and 8.54 ± 4.19 ml/s at 9 months (p = NS). PVR baseline 59.62 ± 54.49, 64.59 ± 58.71 (p = NS) at 1 month, and 68.82 ± 77.72 (p = NS) at 9 months. Sexual function: IIEF baseline 19.38 ± 6.25, 14.06 ± 8.65 at 1 month (p = .011), and 15.4 ± 8.41 at 9 months, (p = NS). Video review of patients with disorders showed potential damage at the site of ligation of IMA (high hypogastric plexus) in 1 case, lateral and posterior mesorectum dissection (hypogastric nerves) in 2 cases, anterior dissection of the Denonvilliers fascia from seminal vesicles in 2 cases.

CONCLUSIONS

GUD at 1 month from LTME for rectal cancer are significant but improve at 9 months. Surgical video review of patients with GUD provides an important tool for detection of lesion sites.

Clinical value of pelvic autonomic nerve preservation during laparoscopic surgery for low rectal cancer

AIM: To observe the function of pelvic autonomic nerve preservation (PANP) during laparoscopic surgery for low rectal cancer.

METHODS: Seventy-six elderly patients who underwent laparoscopic surgery for low rectal cancer were included in this study. These patients were divided into either an observation group (n = 40) or a control group (n = 36). The observation group underwent PANP, while the control group did not undergo PANP. After treatment, the short-term and long-term micturition function was observed. In addition, a three-year follow-up was performed, and the quality of life was scored at the last follow-up.

RESULTS: The percentage of patients who had improved short-term and long-term micturition function was significantly higher in the observation group than in the control group (17.50% vs 47.22%, 0% vs 5.56%, both P < 0.05). Psychological state (SAS, SDS) and self esteem (SES) scores were significantly better in the observation group than in the control group (36.64 ± 4.27 vs 42.37 ± 4.35, 32.84 ± 3.21 vs 39.43 ± 3.92, 24.45 ± 4.20 vs 18.54 ± 3.20, all P < 0.01).

CONCLUSION: PANP during laparoscopic surgery for low rectal cancer can improve micturition function and patient's quality of life.

Laparoscopic neuromapping in pelvic surgery: scopes of application

BACKGROUND

New developments in intraoperative electrophysiological neuromonitoring for conventional surgery are providing further insights into functional neuroanatomy and nerve-sparing in the minor pelvis. The aim of this study was to open up potential scopes of application in laparoscopy.

METHODS

Ten patients with different indications for surgery (presacral tumor excision, n = 2; resection rectopexy. n = 2; low anterior rectal resection, n = 2; proctocolectomy. n = 2; abdomino-perineal excision of the rectum, n = 2) were investigated prospectively. The pelvic autonomic nerves were bilaterally mapped by laparoscopic electric stimulation under simultaneous electromyography of the internal anal sphincter and manometry of the bladder. Stimulation results were compared to patients' anorectal and urogenital functional outcome.

RESULTS

In all the operations laparoscopic neuromapping (LNM) was technically feasible. Laparoscopy enabled excellent visibility of pelvic neural structures for simple and differentiated electric stimulation. In all cases LNM resulted in significantly evoked electromyographic potentials and intravesical pressure rises. The technique facilitated electrophysiological determination of functional neuroanatomical topography in the minor pelvis. The stimulation results were suitable to confirm laparoscopic nerve-sparing and compatible with patients' anorectal and urogenital functional outcome.

CONCLUSIONS

LNM is technically feasible and opens up a new dimension for verification of functional nerve integrity. Further developments and investigations are mandatory to evaluate its role for laparoscopic nerve-sparing procedures.

Is intraoperative neuromonitoring associated with better functional outcome in patients undergoing open TME? Results of a case-control study

AIMS

Intraoperative neuromonitoring (IONM) aims to control nerve-sparing total mesorectal excision (TME) for rectal cancer in order to improve patients' functional outcome. This study was designed to compare the urogenital and anorectal functional outcome of TME with and without IONM of innervation to the bladder and the internal anal sphincter.

METHODS

A consecutive series of 150 patients with primary rectal cancer were analysed. Fifteen match pairs with open TME and combined urogenital and anorectal functional assessment at follow up were established identical regarding gender, tumour site, tumour stage, neoadjuvant radiotherapy and type of surgery. Urogenital and anorectal function was evaluated prospectively on the basis of self-administered standardized questionnaires, measurement of residual urine volume and longterm-catheterization rate.

RESULTS

Newly developed urinary dysfunction after surgery was reported by 1 of 15 patients in the IONM group and by 6 of 15 in the control group (p = 0.031). Postoperative residual urine volume was significantly higher in the control group. At follow up impaired anorectal function was present in 1 of 15 patients undergoing TME with IONM and in 6 of 15 without IONM (p = 0.031). The IONM group showed a trend towards a lower rate of sexual dysfunction after surgery.

CONCLUSIONS

In this study TME with IONM was associated with significant lower rates of urinary and anorectal dysfunction. Prospective randomized trials are mandatory to evaluate the definite role of IONM in rectal cancer surgery.

Evaluation of two-dimensional intraoperative neuromonitoring for predicting urinary and anorectal function after rectal cancer surgery

PURPOSE

The aim of this study was to compare the results of two-dimensional intraoperative neuromonitoring (IONM) with the postoperative urinary and anorectal function of rectal cancer patients.

METHODS

A consecutive series of 35 patients undergoing low anterior resection were investigated prospectively. IONM was performed with electric stimulations of the pelvic splanchnic nerves under simultaneous manometry of the bladder and electromyography (EMG) of the internal anal sphincter (IAS). Urinary and anorectal function were evaluated preoperatively and at follow-up by standardized questionnaires, digital rectal examination scoring system, and long-term catheterization rate.

RESULTS

The rate of postoperative newly developed bladder dysfunction was 17 %. IONM with bladder manometry had a sensitivity of 100 %, specificity of 96 %, positive predictive value of 83 %, negative predictive value of 100 %, and overall accuracy of 97 %, respectively. The proportion of patients with severely impaired anorectal function at follow-up was 8 %. The sensitivity, specificity, and positive and negative predictive values for IONM with EMG of the IAS were, respectively, 100, 96, 67, and 100 % with an accuracy of 96 %. The degree of agreement for IONM with EMG of the IAS was good for anorectal function (к = 0.780) and poor for urinary function (к = 0.119). IONM with bladder manometry yielded a very good degree of agreement for urinary function (к = 0.891) and a fair agreement for anorectal function (к = 0.336).

CONCLUSIONS

The two-dimensional IONM method is suitable for verification of bladder and IAS innervation. Accurate prediction of urinary and anorectal function necessitates both bladder manometry and EMG of the IAS.