The 'multilayer' theory of Denonvilliers' fascia: anatomical dissection of cadavers with the aim to improve neurovascular bundle preservation during rectal mobilization

The "Y"-shaped Denonvilliers' fascia and its adjacent relationship with the urogenital fascia based on a male cadaveric anatomical study

BACKGROUND

Controversies regarding the anatomical structure of Denonvilliers' fascia and its relationship with surrounding fasciae have sparked a heated discussion, especially concerning whether Denonvilliers' fascia is multilayered. This study aimed to expound on the anatomical structure of Denonvilliers' fascia and its correlation with the peritoneum from the sagittal view and clarify the complex fascial relationship.

METHODS

Our study was performed on 20 adult male pelvic specimens fixed in formalin, including 2 entire pelvic specimens and 18 semipelvic specimens. The local adjacent organs and fasciae were dissected, and Denonvilliers' fascia was observed and removed for histological examination.

RESULTS

Denonvilliers' fascia was typically single-layered and tough. On the sagittal plane, the peritoneum constituting the peritoneal reflection and Denonvilliers' fascia formed a "Y" shape. Denonvilliers' fascia originated from the peritoneal reflection, extended along the ventral side of the seminal vesicles and prostate, continuing caudally; its bilateral sides closely connected to the urogenital fascia (UGF) of the pelvic wall. In addition, histology preliminarily indicated that the basal cell layers of the peritoneum and Denonvilliers' fascia were continuous and formed a "Y" shape. Furthermore, the basal cells of the two peritonea extended to Denonvilliers' fascia, creating a fused double-layered structure. Some tiny blood vessels or a network of such vessels extended from the peritoneum to Denonvilliers' fascia.

CONCLUSION

Denonvilliers' fascia, the extension of the peritoneum in the pelvic floor, appears as a single-layered "Y"-shape on the sagittal plane. Our study provides new support for the peritoneal fusion theory. Understanding the anatomical characteristics of Denonvilliers' fascia and its relationship with the UGF is of guiding significance for inexperienced colorectal surgeons to conduct rectal cancer surgery.

The "terminal line": a novel sign for the identification of distal mesorectum end during TME for rectal cancer

Background

Although the clinical importance of complete, intact total mesorectal excision (TME) is the widely accepted standard for decreasing local recurrence of rectal cancer, the residual mesorectum still represents a significant component of resection margin involvement. This study aimed to use a visible intraoperative sign to detect the distal mesorectal end to ensure complete inclusion of the mesorectum and avoid unnecessary over-dissection.

Methods

The distal mesorectum end was investigated retrospectively through a review of 124 operative videos at the Union Hospital of Fujian Medical University (Fujian, China) and Cleveland Clinic (Ohio, USA) by two independent surgeons who were blinded to each other. Furthermore, 28 cadavers and 44 post-operative specimens were prospectively examined by hematoxylin and eosin (H&E) staining and Masson's staining to validate and confirm the findings of the retrospective part. Univariate and multivariate analyses were carried out to detect the independent factors that can affect the visualization of the distal mesorectal end.

Results

The terminal line (TL) is the distal mesorectal end of the transabdominal and transanal TME (taTME) and appears as a remarkable pearly white fascial structure extending posteriorly from 2 to 10 o'clock. Histopathological examination revealed that the fascia propria of the rectum merges with the presacral fascia at the TL, beyond which the mesorectum ends, with no further downward extension. In the retrospective observation, the TL was seen in 56.6% of transabdominal TME and 56.0% of taTME operations. Surgical approach and tumor distance from the anal verge were the independent variables that directly influenced the detection of the TL (P = 0.03 and P = 0.01).

Conclusion

The TL is a visible sign where the transabdominal TME should end and the taTME should begin. Recognition of the mesorectal end may impact the certainty of complete mesorectum inclusion. Further clinical trials are needed to confirm the preliminary findings.

Effect of partial preservation versus complete preservation of Denonvilliers' fascia on postoperative urogenital function in male patients with low rectal cancer (PREDICTION): protocol of a multicentre, prospective, randomised controlled clinical trial

INTRODUCTION

Total mesorectal excision (TME) has been the gold standard for the surgical treatment of mid-low rectal cancer, but traditional TME removal of Denonvilliers' fascia (DVF) is too low and is prone to damage the connecting branches of the bilateral neurovascular bundles, which can lead to posturogenital dysfunction. A recently published multicenter randomised controlled trial revealed that TME with complete preservation of DVF (CP-DVF) has protective effects on postoperative urogenital function for male patients with rectal cancer with specific staging and location (preoperative staging T1-4N0-2M0, but T1-2 for anterior rectal wall). Our previous studies have confirmed that TME with partial preservation of DVF (PP-DVF) could also achieve satisfactory results regardless of the circumferential location of the tumour. However, there is a lack of randomised controlled trials to prove that the efficacy of TME with PP-DVF is equivalent to that with CP-DVF with respect to postoperative urogenital function.

METHODS AND ANALYSIS

This study is a prospective, multicentre, equivalent design, open-label randomised clinical trial in which 278 male patients with low rectal cancer will be recruited from 11 large-scale gastrointestinal medical centres in China. Patients will be randomly assigned to undergo PP-DVF or CP-DVF. We will test the hypothesis that PP-DVF is similar to CP-DVF with respect to sexual function at postoperative month 12 (5-item version of the International Erectile Function Index Questionnaire and ejaculation function classification). The secondary outcomes include the assessment of urinary function, surgical safety and oncological outcomes.

ETHICS AND DISSEMINATION

This trial has been approved by the Institutional Review Board of Fujian Medical University Union Hospital (2020YF016-01) and is filed on record by all other centres. Written informed consent will be obtained from all eligible participants before enrolment. The trial's results will be disseminated via peer-reviewed scientific journals and conference presentations.

TRIAL REGISTRATION NUMBER

ChiCTR2000034892.

Anatomy of the vesicovaginal fascia and its relation to branches of the inferior hypogastric plexus

The inferior hypogastric plexus (IHP) lies in the extraperitoneal pelvis, and supplies branches to pelvic and perineal viscera. In men, the rectoprostatic fascia (Denonvillier's fascia) forms a distinct double fascial layer between the seminal glands and the rectum. The hypogastric nerve projections to the prostate and seminal glands run anterior to this. An analagous fascial layer in women between the vagina and cervix posteriorly and the urinary bladder anteriorly has recently been described. The purpose of this study was to examine the anatomy of the vesicovaginal fascia (VVF) and to determine its relationship to the anterior branches of the IHP. This dissection study examined the fascial layers between the posterior urinary bladder and anterior vagina/cervix (VVF) in 15 female embalmed cadavers and three fresh specimens. Anterior branches of the IHP were identified and followed distally. The relationship between these nerve projections and the VVF was examined. In 16 dissection, the VVF was identified as a complete fascial plane extending beneath the vesicouterine pouch to the neck of the bladder inferiorly and to the endopelvic fascia laterally. Anterior projections from the hypogastric nerves and IHP maintained an extraperitoneal course passing anteriorly to the VVF towards the urinary bladder The VVF is a distinct fascial structure and projections of the hypogastric nerves pass anterior to this. This may have implications for nerve sparing hysterectomy.

Navigating surgical anatomy of the Denonvilliers’ fascia and dissection planes of the anterior mesorectum with a cadaveric simulation model

Anterior dissection of the rectum in the male pelvis represents one of the most complex phases of total meso-rectal excision. However, the possible existence of different anatomical planes is controversial and the exact anatomical topography of Denonvilliers’ fascia is still debated. The aim of the study is to accurately define in a cadaveric simulation model the existence and boundaries of Denonvilliers’ fascia, identifying the anatomical planes suitable for surgical dissection. The pelvises of 31 formalin-preserved male cadavers were dissected. Careful and detailed dissection was carried out to visualize the anatomical structures and the potential dissection planes, simulating an anterior meso-rectum dissection. Denonvilliers’ fascia was identified in 100% of the pelvises, as a single-layer fascia that originates from the peritoneal reflection and descends until its firm adhesion to the prostate capsule. The fascia divides the space providing an anterior and a posterior plane. Anteriorly to the fascia, during the caudal dissection, its firm adhesion to the prostate capsule forces to section it sharply. The cadaveric simulation model allowed an accurate description of Denonvilliers’ fascia, defining several planes for anterior dissection of the meso-rectum.

Denonvilliers’ Fascia: The Prostate Border to the Outside World

Simple Summary

Prostate cancer is a very common neoplasm in men, with surgery being a valuable tool for its successful management. The prostate gland lies deep in the male pelvis with several sheets of fibrous membranes surrounding it along anterior, lateral, and posterior surfaces. These membranes are called fasciae. Arteries, veins, and nerve fibers that are important for erectile function and continence can be found within these fasciae. An important fascia covering the posterior surface of the prostate and separating it from the rectum is Denonvilliers’ fascia. This structure is important for the confinement of cancer within the prostate and for completing an operation without damaging the nerves responsible for erectile function and continence while also removing all neoplastic tissue. This review covers the anatomical aspects of this structure, along with providing some clinical insight on how to use this knowledge to improve clinical outcomes.

Abstract

The fascial structure around the prostate has been a controversial issue for several decades, but its role in radical prostatectomy is crucial to achieving successful nerve-sparing surgery. One of the fasciae surrounding the prostate is Denonvilliers’ fascia, forming its posterior border with the rectum and enclosing along its layers several fibers of the neurovascular bundle. This review focuses on embryological and anatomical points of Denonvilliers’ fascia, aiming to provide a summary for the operating general surgeons and urologists of this area.

OUP accepted manuscript

Background

The relative anatomical understanding of the perirectal fasciae is of paramount importance for the proper performance of total mesorectal excision (TME). This study was to demonstrate the planes of TME and validates the intraoperative findings using cadaveric observations.

Methods

In this combined retrospective and prospective study, bilateral attachment of the rectosacral fascia (RSF) was observed in 28 cadaveric specimens (male, n = 14; female, n = 14). From January 2018 to December 2019, surgical videos of 67 patients who underwent laparoscopic TME at the Affiliated Union Hospital of Fujian Medical University (Fuzhou, China) were reviewed and interpreted with the cadaveric findings.

Results

The RSF (synonym: Waldeyer's fascia) is the end of the pre-hypogastric fascia at the level of S4 and comprises two layers (upper and lower). These two layers provide double fascial protection for the venous sacral plexus. It inserts into the fascia propria of the rectum along a broad horizontal arc that merges anterolaterally in an oblique downward direction until it meets the posterolateral merge of Denonvilliers' fascia at the lateral rectal ligament (LRL). This ligament does not look like a true ligament but is more likely to be a fascial combination that cushions the rectal innervation and middle rectal vessels.

Conclusions

Understanding the lateral attachment of RSF and its contribution to LRL provides invaluable surgical guidance to dissect this critical area. Therefore, lateral dissection is proposed from the anterior to the posterior direction to find the correct plane that guarantees an intact mesorectal envelope to protect the important nearby nerve structures.

Denonvilliers’ fascia acts as the fulcrum and hammock for continence after radical prostatectomy

Background

Radical prostatectomy (RP) is the primary treatment of localized prostate cancer. Immediate urinary incontinence post-RP was still common and depressing without specific reason.

Methods

A multicenter cohort of 154 consecutive patients from 2018 to 2020, who was diagnosed with localized prostate cancer underwent either modified mini-incision retropubic radical prostatectomy (Mmi-RRP) or laparoscopic radical prostatectomy (LRP) or robotic-assisted radical prostatectomy (RARP). Seventy-two patients with Denonvilliers’ fascia (DF) spared were included in DFS (Denonvilliers’ fascia sparing) group. Whereas eighty-two patients with DF completely or partially dissected were set as Group Control. The primary outcome was immediate continence (ImC). Continuous data and categorical data were analyzed with t-test and Chi-square test, respectively. Odds ratios (ORs) were calculated with logistic regression.

Results

Urinary continence of Group DFS was significantly better than that of Group Control at each time point within one year after operation. Incidence rate of continence in Group DFS and Group Control were 83.3% vs 13.4% (P < 0.01) for ImC, 90.3% vs 30.5% (P < 0.01) at 3 months, 91.7% vs 64.6% (P < 0.01) at 6 months, and 93.1% vs 80.5% (P = 0.02) at 1 year after operation, respectively. Positive surgical margin (PSM) showed no significant difference (20.8% vs 20.7%, P = 1.0). In multivariate analysis, DFS showed importance for ImC post RP (OR = 26.4, P < 0.01).

Conclusions

Denonvilliers’ fascia acted as the fulcrum and hammock for continence post RP. Preservation of DF contributed to better continence after RP without increase of PSM.

Trail registration Our research was conducted retrospectively and approved by the ethical committees of Minhang Hospital, but not registered.

Three-dimensional anatomy of the Denonvilliers' fascia after micro-CT reconstruction

An understanding of the anatomy of the Denonvilliers’ fascia is essential for successful surgical outcomes for patients with rectal cancer in the mid- to lower regions, especially near the seminal vesicles and prostate in males. Whether the correct surgical plane during a total mesorectal excision should be anterior or posterior to the Denonvilliers’ fascia is currently under debate. This study aimed to investigate the Denonvilliers’ fascia using micro-computed tomography (micro-CT) to acquire three-dimensional images nondestructively for assessments of the relationship between the Denonvilliers’ fascia, the mesorectal fascia, and neurovascular bundles to elucidate the correct anterior total mesorectal excision plane. Eight specimens were obtained bilaterally from four fresh human cadavers. Four specimens were stained with phosphotungstic acid to visualize the soft tissue, and micro-CT images were obtained; the other four specimens were stained with Masson’s trichrome to visualize connective tissue. Micro-CT images corroborate that the Denonvilliers’ fascia consists of a multilayered structure that separates the rectum from the seminal vesicles and the prostate. Specimens stained with Masson’s trichrome showed that the urogenital neurovascular bundle located at the posterolateral corner of the prostate is separated from the mesorectum by the Denonvilliers’ fascia. For the preservation of autonomic nerves necessary for urogenital function and optimal oncologic outcomes in patients with rectal cancer, a successful mesorectal excision requires a dissection plane posterior to the Denonvilliers’ fascia.

Analysis of presacral tissue structure in LARS and the prevention of LARS by reconstruction of presacral mesorectum with pedicled greater omentum flap graft

BACKGROUND

The greater omentum has played a unique biological role in regenerative surgery. The aim of our study was to alter the anterior sacral structure by filling the anterior sacral space with the greater omentum and evaluate its effect on the low anterior resection syndrome (LARS) after total mesorectal excision (TME) surgery for low rectal cancer.

METHODS

We retrospectively collected clinical data of patients with primary low rectal cancer who underwent TME and ileostomy closure in our hospital from March 2018 to March 2020. Spearman correlation analysis was conducted to analyze the correlation between postoperative mesorectal fascia (MRF) thickness and LARS score. Subsequently, we prospectively used a tipped greater omental flap graft to reconstruct the anterior rectal sacral structures (MRF reconstruction) in 17 patients and compared LARS scores and rectal compliance (RC) at week 12 after closure of the ileostomy in both groups.

RESULTS

There were 47 patients with No-MRF reconstruction (31 males, mean age 60.68 ± 9.21 years) and 17 with MRF reconstruction (10 males, mean age 49.82 ± 14.74 years). Correlation analysis indicated that MRF thickness and RC were negatively correlated with LARS severity (p < 0.05). The LARS score of patients with MRF reconstruction at 12 weeks was significantly better than that of those with No-MRF reconstruction (32.97 ± 2.65 vs. 26.94 ± 1.52, p = 0.001), and the RC of MRF reconstruction were lower (2.80 ± 0.55 vs. 3.67 ± 0.38, p = 0.001). In addition, MRF reconstruction and No-MRF reconstruction have the similar incidence of postoperative complications (p = 0.156). No hemorrhage or necrosis of the greater omentum flap was observed in any of the patients.

CONCLUSIONS

Greater omentum flap transplantation can significantly improve the symptoms of LARS at 12 weeks after ileostomy closure and we expect it to become a new surgical procedure for the treatment of low rectal cancer.

Positional relationship between the lateral border of Denonvilliers' fascia and pelvic plexus

Denonvilliers' fascia is an important landmark of the dissection layer during prostate or rectal surgeries. However, there are few reports on its lateral extension. This anatomical study aimed to define the lateral border of Denonvilliers' fascia and use it as an anatomical landmark to identify the origin and distribution of the nerve branches of the pelvic plexus. We investigated the lateral extent and position of the lateral border of Denonvilliers' fascia through macroscopic examination of 12 pelvic halves from eight cadavers and histological examination of two cadavers. The Denonvilliers' fascia extended laterally to be attached to the pelvic plexus on the lateral border. The origins of nerve branches from the pelvic plexus to the pelvic organs, except the rectum, were located anterior or anterosuperior to the lateral border of Denonvilliers' fascia. The origins of nerve branches to the prostate were mainly anterior to the lateral border of Denonvilliers' fascia; however, in 3/12 pelvic halves, the nerve branches originated in the region posteroinferior to the lateral border of Denonvilliers' fascia. The attachment point of Denonvilliers' fascia to the prostate was more superior in these three pelvic halves (distance from the top point of the posterior surface of the prostate to the attachment point, 5.6 ± 1.9 mm) than that in the other nine pelvic halves (10.1 ± 3.6 mm). The lateral border of Denonvilliers' fascia is closely related to the pelvic plexus, suggesting its usefulness as an anatomical landmark to identify the origin of nerve branches from the pelvic plexus.

The Female Pelvic Floor Fascia Anatomy: A Systematic Search and Review

The female pelvis is a complex anatomical region comprising the pelvic organs, muscles, neurovascular supplies, and fasciae. The anatomy of the pelvic floor and its fascial components are currently poorly described and misunderstood. This systematic search and review aimed to explore and summarize the current state of knowledge on the fascial anatomy of the pelvic floor in women. Methods: A systematic search was performed using Medline and Scopus databases. A synthesis of the findings with a critical appraisal was subsequently carried out. The risk of bias was assessed with the Anatomical Quality Assurance Tool. Results: A total of 39 articles, involving 1192 women, were included in the review. Although the perineal membrane, tendinous arch of pelvic fascia, pubourethral ligaments, rectovaginal fascia, and perineal body were the most frequently described structures, uncertainties were identified in micro- and macro-anatomy. The risk of bias was scored as low in 16 studies (41%), unclear in 3 studies (8%), and high in 20 studies (51%). Conclusions: This review provides the best available evidence on the female anatomy of the pelvic floor fasciae. Future studies should be conducted to clarify the discrepancies highlighted and accurately describe the pelvic floor fasciae.

Surgical Anatomy of the Rectovaginal Space: Does a Standalone Rectovaginal Septum or Denonvilliers Fascia Exist in Women?

BACKGROUND

Below the anterior peritoneal reflection, the anterior rectal wall and mesorectum are separated from the posterior vaginal wall by a virtual rectovaginal space. In this space, the description of a specific and independent rectovaginal septum as a female counterpart of Denonvilliers fascia has been the subject of debate over the years.

OBJECTIVE

The aim of this study is to perform an accurate anatomical study of the rectovaginal area in a cadaveric simulation model of total mesorectal excision to evaluate the possible structures and the dissection planes contained within the rectovaginal space.

DESIGN AND SETTING

This is a cadaveric study performed at the University of Valencia.

PATIENTS

The pelvises of 25 formalin-preserved female cadavers were dissected. All the included specimens were sectioned in a midsagittal plane, at the level of the middle axis of the anal canal.

MAIN OUTCOME MEASURES

Careful and detailed dissection was performed to visualize the anatomical structures and potential dissection planes during anterior mesorectal dissection in cadavers. Histological sections were made of the posterior vaginal wall.

RESULTS

The rectovaginal space contains loose areolar tissue that allows an easy dissection plane distally. A distinct and independent rectovaginal fascia or septum is not present. The existence of 3 layers fused together in the posterior vaginal wall can be identified more or less precisely because of their different coloration. The histological study confirms this macroscopic arrangement of the posterior vaginal wall in 3 layers: the mucosa, the muscular, and the adventitia. An independent rectovaginal septum can be generated only with a splitting of the adventitia.

LIMITATIONS

The cadaveric pelvic specimens of the oldest donors might have had age-related degeneration.

CONCLUSIONS

The present anatomical study has shown only a plane of loose areolar tissue between the rectal and vaginal wall. We can conclude that there is no independent fascia or septum in the rectovaginal space. See Video Abstract at http://links.lww.com/DCR/B456. ANATOMÍA QUIRÚRGICA DEL ESPACIO RECTOVAGINAL: ¿EXISTE UN TABIQUE RECTOVAGINAL INDEPENDIENTE O UNA FASCIA DE DENONVILLIERS EN LAS MUJERES: Debajo del reflejo peritoneal anterior, la pared rectal anterior y el mesorrecto están separados de la pared vaginal posterior por un espacio rectovaginal virtual. En este espacio, la descripción de un tabique rectovaginal independiente específico como contraparte femenina de la fascia de Denonvilliers ha sido objeto de debate a lo largo de los años.Realizar un estudio anatómico preciso del área rectovaginal en un modelo de simulación cadavérica de escisión mesorrectal total, con el fin de evaluar las posibles estructuras y los planos de disección contenidos en el espacio rectovaginal.estudio cadavérico realizado en la Universidad de Valencia.Se disecaron las pelvis de 25 cadáveres femeninos conservados en formalina. Todas las muestras incluidas fueron seccionadas en un plano medio sagital, a la altura del eje medio del canal anal.Se llevó a cabo una disección cuidadosa y detallada para visualizar las estructuras anatómicas y los posibles planos de disección durante la disección mesorrectal anterior en cadáveres. Se realizaron cortes histológicos de la pared vaginal posterior.El espacio rectovaginal contiene tejido areolar laxo que permite un plano de disección fácil distalmente. No hay fascia o tabique rectovaginal distinto e independiente. La existencia de tres capas fusionadas en la pared vaginal posterior puede identificarse con mayor o menor precisión debido a su diferente coloración. El estudio histológico confirma esta disposición macroscópica de la pared vaginal posterior en tres capas: la mucosa, la muscular y la adventicia. Un tabique rectovaginal independiente solo se puede generar con una división de la adventicia.Las muestras pélvicas de cadáveres de los donantes más antiguos pueden haber tenido degeneración relacionada con la edad.El estudio anatómico actual solo ha mostrado un plano de tejido areolar laxo entre la pared rectal y vaginal. Podemos concluir que no hay fascia o tabique independiente en el espacio rectovaginal. Consulte Video Resumen en http://links.lww.com/DCR/B456. (Traducción-Dr. Adrian Ortega).

Optimal Complete Rectum Mobilization Focused on the Anatomy of the Pelvic Fascia and Autonomic Nerves: 30 Years of Experience at Severance Hospital

The primary goal of surgery for rectal cancer is to achieve an oncologically safe resection, i.e., a radical resection with a sufficient safe margin. Total mesorectal excision has been introduced for radical surgery of rectal cancer and has yielded greatly improved oncologic outcomes in terms of local recurrence and cancer-specific survival. Along with oncologic outcomes, functional outcomes, such as voiding and sexual function, have also been emphasized in patients undergoing rectal cancer surgery to improve quality of life. Intraoperative nerve damage or combined excision is the primary reason for sexual and urinary dysfunction. In the past, these forms of damage could be attributed to the lack of anatomical knowledge and poor visualization of the pelvic autonomic nerve. With the adoption of minimally invasive surgery, visualization of nerve structure and meticulous dissection for the mesorectum are now possible. As the leading hospital employing this technique, we have adopted minimally invasive platforms (laparoscopy, robot-assisted surgery) in the field of rectal cancer surgery and standardized this technique globally. Here, we review a standardized technique for rectal cancer surgery based on our experience at Severance Hospital, suggest some practical technical tips, and discuss a couple of debatable issues in this field.

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.

Seminal Vesicle Adherent to Rectal Wall Following Neoadjuvant Chemoradiotherapy: A Potential False-Positive Diagnostic Pitfall

The standard of care for stage T3 and stage T4 rectal adenocarcinomas involves neoadjuvant chemoradiotherapy followed by either low anterior resection or abdominopelvic resection. The presence of residual adenocarcinoma or positive surgical margins provides useful prognostic information and can influence ongoing adjuvant therapy. Although uncommon, mimics of treated adenocarcinoma may be present in the surgical specimen. A high index of suspicion is critical in avoiding potential false-positive pitfalls, and the exclusion of mimics of treated adenocarcinoma is paramount to accurate diagnosis and treatment. Seminal vesicle epithelium has long been a challenge in differentiating prostatic adenocarcinoma from benign epithelium. However, the role of incidental seminal vesiculectomy in rectal resections due to fibrous adhesion to the rectal wall secondary to chemoradiation has not been studied. As the seminal vesicle epithelium can show markedly atypical nuclei with radiation-type effect at baseline, the potential risk of misinterpretation as residual adenocarcinoma is high. In this article, we present 2 case reports of rectal adenocarcinoma treated with neoadjuvant chemoradiotherapy followed by transabdominal resection (low anterior resection or abdominopelvic resection) with incidental seminal vesiculectomies mimicking either residual adenocarcinoma or residual adenocarcinoma at a margin of resection.