The development and structure of the mesentery.

The position of abdominal organs, and mechanisms by which these are centrally connected, are currently described in peritoneal terms. As part of the peritoneal model of abdominal anatomy, there are multiple mesenteries. Recent findings point to an alternative model in which digestive organs are connected to a single mesentery. Given that direct evidence of this is currently lacking, we investigated the development and shape of the entire mesentery. Here we confirm that, within the abdomen, there is one mesentery in which all abdominal digestive organs develop and remain connected to. We show that all abdominopelvic organs are organised into two, discrete anatomical domains, the mesenteric and non-mesenteric domain. A similar organisation occurs across a range of animal species. The findings clarify the anatomical foundation of the abdomen; at the foundation level, the abdomen comprises a visceral (i.e. mesenteric) and somatic (i.e. musculoskeletal) frame. The organisation at that level is a fundamental order that explains the positional anatomy of all abdominopelvic organs, vasculature and peritoneum. Collectively, the findings provide a novel start point from which to systemically characterise the abdomen and its contents.

Propensity score-matched analysis comparing laparoscopic to robotic surgery for colorectal cancer shows comparable clinical and oncological outcomes.

Robotic colorectal surgery is gaining popularity. The objective of this study was to compare clinical and cancer outcomes in propensity-score matched cohorts (PSM-1:1) undergoing colorectal cancer (CRC) surgery performed using laparoscopic or robotic surgery in a single institution. A PSM cohort comparison was performed in a tertiary referral cancer and National accredited rectal cancer surgery centre. Patients with CRC undergoing laparoscopic or robotic resection with curative intent from 2016 to 2019 (inclusive) were assessed for inclusion. Matched cohorts were selected using a 1:1 ratio. Statistical analysis was performed using SPSS, version 22. 128 patients were analysed [laparoscopic (n = 64); robotic (n = 64)]. Median age was 64 years (29-84 years). 55% (n = 70) of patients were male, 45% female (n = 58). SSI rates were slightly lower in the robotic group [10.9% (n = 7) v 12.5% (n = 8) p = 0.40]. Anastomotic leak rates were equal in both groups [5.4% (n = 3)]. All but one patient received an R0 resection in each group, median LNY was 14 in the robotic group and 12 in the laparoscopic group (p = 0.004) and no difference in disease recurrence (p = 0.465) or survival (p = 0.886) was observed. Structured introduction of a robotic colorectal programme over a 3-year period has resulted in equivalent outcomes with an established laparoscopic programme for CRC.