Mesorectum, is it an appropriate term?

Mesenteric excision of upper esophagus: a concept for rational anatomical lymphadenectomy of the recurrent laryngeal nodes in thoracoscopic esophagectomy

BACKGROUND

The recurrent laryngeal nerve (RLN) lymph nodes are among the most frequently involved lymph nodes in esophageal cancer. Surgical removal of these lymph nodes is considered beneficial for postoperative prognosis, especially in patients with squamous cell carcinoma. Unfortunately, the precise surgical anatomy of the upper mediastinum is not well understood and no distinct high-resolution images are currently available.

METHODS

In this article, we provide a simple intuitive concept of upper mediastinal surgical anatomy that could facilitate rational anatomical lymphadenectomy of the RLN lymph nodes. The essential concept of this mesenteric excision is to mobilize mesoesophagus including RLN in an en bloc fashion and to save RLN laterally by incising visceral sheath. This is applicable identically to both right and left upper mediastinum.

RESULTS

Between January 2009 and December 2017, thoracoscopic esophagectomy with upper mediastinal lymphadenectomy for primary esophageal cancer was performed in 189 patients. Median thoracoscopic procedure time was 297 (range 205-568) min and median intraoperative blood loss was 70 ml (range unmeasurable up to 2545 ml). Median number of harvested upper mediastinal lymph nodes was 12. Postoperative complication of Clavien-Dindo classification grade III or higher events was observed in 14% of patients. RLN palsy of grade II or higher occurred in 20 patients (11%).

CONCLUSION

The mesoesophagus in the upper mediastinum is an anatomical unit surrounded by fibrous connective tissue containing the esophagus, trachea, tracheoesophageal vessels, lymphatic tissue, and RLNs. Thus, mesenteric excision of esophagus is defined to resect this area by sparing trachea and RLNs for rational anatomical lymphadenectomy. We believe that this concept makes upper mediastinal lymphadenectomy safer and more appropriate.

Urogenital dysfunctions after treatment of rectal cancer

A significant part of rectal cancer survivors will experience urogenital dysfunction induced by the treatment. Significant progress has been made in order to improve the total mesorectal technique through different approaches (open, laparoscopic, robotic, transanal). Rectal cancer surgery is technically difficult notably deep in the pelvis, and therefore the most frequent cause of the postoperative dysfunction is the surgical nerve damage of the autonomic nerves at this level. The main objectives of these efforts were to obtain maximal oncological results and to achieve better functional outcomes including less postoperative urogenital dysfunctions. Our purpose was to build a comprehensive review of the existing literature data regarding this issue from past to present.

Magnetic resonance imaging cannot predict histological tumour involvement of a circumferential surgical margin in rectal cancer

AIM

Several recent studies have attempted to evaluate the accuracy of preoperative magnetic resonance imaging (MRI) in predicting the likelihood of tumour involvement of the postoperative circumferential resection margin (CRM) in rectal cancer with the intention of selecting patients who might benefit from neoadjuvant therapy and as a guide to surgery. The aim of this study was to assess whether such studies can provide a valid answer as to whether preoperative MRI can accurately predict CRM involvement by tumour.

METHOD

The study design and methodology of studies on this topic were critically examined.

RESULTS

Features identified as affecting the efficacy of these studies were: representativeness of patients, definition of the margin assessed by MRI and by histology, lack of blinding of surgeons and pathologists to MRI results, effect of neoadjuvant treatment, and number of patients studied.

CONCLUSION

Because of methodological inadequacies in studies completed to date, there is insufficient evidence of the ability of a positive MRI result to predict an involved CRM. Although MRI may be able to identify a tumour that has extended to the mesorectal fascia and/or intersphincteric plane, logically, it cannot indicate where the surgical boundary of the resection will ultimately lie, and therefore cannot validly predict an involved CRM and should not be relied upon for this purpose.

Anatomy of the lateral ligaments of the rectum: A controversial point of view

The existence and composition of the lateral ligaments of the rectum (LLR) are still the subjects of anatomical confusion and surgical misconception up to now. Since Miles proposed abdominoperineal excision as radical surgery for rectal cancer, the identification by “hooking them on the finger” has been accepted by many surgeons with no doubt; clamping, dividing and ligating are considered to be essential procedures in mobilization of the rectum in many surgical textbooks. But in cadaveric studies, many anatomists could not find LLR described by the textbooks, and more and more surgeons also failed to find LLR during the proctectomy according to the principle of total mesorectal excision. The anatomy of LLR has diverse descriptions in literatures. According to our clinical observations, the traditional anatomical structures of LLR do exist; LLR are constant dense connective bundles which are located in either lateral side of the lower part of the rectum, run between rectal visceral fascia and pelvic parietal fascia above the levator ani, and covered by superior fascia of pelvic diaphragm. They are pathways of blood vessels and nerve fibers toward the rectum and lymphatic vessels from the lower rectum toward the iliac lymph nodes.