Reconstructing topography and extent of injury to the superior mesenteric artery plexus in right colectomy with extended D3 mesenterectomy: a composite multimodal 3-dimensional analysis

Robotic right-sided colon cancer surgery: Dissecting the outermost layer of the autonomic nerve along the superior mesenteric artery

In right-sided colon cancer surgery, lymph node dissection around the superior mesenteric artery is necessary but technically challenging. Here we introduce the concept of "outermost layer-oriented robotic surgery" to improve the safety, efficacy, and reproducibility of superior mesenteric artery nodal dissection. In this procedure, the thin, loose connective tissue layer between the autonomic nerve sheath of the superior mesenteric artery and adipose tissue bearing lymph nodes, termed "the outermost layer of the autonomic nerve," is dissected. The procedure exposes the outermost layer of the nerve plexus covering the surface of the superior mesenteric artery with a width of approximately 1 cm, enabling direct visualization of the anatomy of the main arteries and, if they exist, jejunal veins which cross the superior mesenteric artery ventrally. This allows for sufficient dissection of main lymph nodes at the roots of the ileocolic artery, right colic artery, and middle colic artery and minimizes the risk of unforeseen bleeding. Thirty-nine patients underwent robotic right hemicolectomy with this procedure. No intraoperative complications were observed. The median number of dissected lymph nodes was 50, including 16 main lymph nodes. The median operative time was 284 min, blood loss was 50 mL, and the median postoperative hospital stay was 8 days. Postoperative complications included two cases of Clavien-Dindo classification grade II, with no cases of grade III or higher. Chylous leakage as well as intractable diarrhea were not observed in any case. These findings demonstrate that the procedure can achieve safe and reliable lymph node clearance.

Gastrointestinal functions after laparoscopic right colectomy with intracorporeal anastomosis: a pilot randomized clinical trial on effects of abdominal drain, prolonged antibiotic prophylaxis, and D3 lymphadenectomy with complete mesocolic excision

PURPOSE

Routine use of abdominal drain or prolonged antibiotic prophylaxis is no longer part of current clinical practice in colorectal surgery. Nevertheless, in patients undergoing laparoscopic right hemicolectomy with intracorporeal anastomosis (ICA), it may reduce perioperative abdominal contamination. Furthermore, in cancer patients, prolonged surgery with extensive dissection such as central vascular ligation and complete mesocolon excision with D3 lymphadenectomy (altogether radical right colectomy RRC) is called responsible for affecting postoperative ileus. The aim was to evaluate postoperative resumption of gastrointestinal functions in patients undergoing right hemicolectomy for cancer with ICA and standard D2 dissection or RRC, with or without abdominal drain and prolonged antibiotic prophylaxis.

METHODS

Monocentric factorial parallel arm randomized pilot trial including all consecutive patients undergoing laparoscopic right hemicolectomy and ICA for cancer, in 20 months. Patients were randomized on a 1:1:1 ratio to receive abdominal drain, prolonged antibiotic prophylaxis or neither (I level), and 1:1 to receive RRC or D2 colectomy (II level). Patients were not blinded. The primary aim was the resumption of gastrointestinal functions (time to first gas and stool, time to tolerated fluids and food). Secondary aims were length of stay and complications' rate.

CLINICALTRIALS

gov no. NCT04977882.

RESULTS

Fifty-seven patients were screened; according to sample size, 36 were randomized, 12 for each arm for postoperative management, and 18 for each arm according to surgical techniques. A difference in time to solid diet favored the group without drain or antibiotic independently from standard or RRC. Furthermore, when patients were divided with respect to surgical technique and into matched cohorts, no differences were seen for primary and secondary outcomes.

CONCLUSION

Abdominal drainage and prolonged antibiotic prophylaxis in patients undergoing right hemicolectomy for cancer with ICA seem to negatively affect the resumption of a solid diet after laparoscopic right hemicolectomy with ICA for cancer. RRC does not seem to influence gastrointestinal function recovery.

Are Metastatic Central Lymph Nodes (D3 volume) in right-sided Colon Cancer a Sign of Systemic Disease? A sub-group Analysis of an Ongoing Multicenter Trial

OBJECTIVE

Assess outcomes of patients with right-sided colon cancer with metastases in the D3 volume after personalized surgery.

BACKGROUND

Patients with central lymph node metastasis (D3-PNG) are considered to have a systemic disease with a poor prognosis. A 3-dimensional definition of the dissection volume allows the removal of all central nodes.

MATERIALS AND METHODS

D3-PNG includes consecutive patients from an ongoing clinical trial. Patients were stratified into residual disease negative (D3-RDN) and residual disease positive (D3-RDP) groups. D3-RDN was further stratified into 4 periods to identify a learning curve. A personalized D3 volume (defined through arterial origins and venous confluences) was removed " en bloc" through medial-to-lateral dissection, and the D3 volume of the specimen was analyzed separately.

RESULTS

D3-PNG contained 42 (26 females, 63.1 SD 9.9 y) patients, D3-RDN:29 (17 females, 63.4 SD 10.1 y), and D3-RDP:13 (9 females, 62.2 SD 9.7 y). The mean overall survival (OS) days were D3-PNG:1230, D3-RDN:1610, and D3-RDP:460. The mean disease-free survival (DFS) was D3-PNG:1023, D3-RDN:1461, and D3-RDP:74 days. The probability of OS/DFS were D3-PNG:52.1%/50.2%, D3-RDN:72.9%/73.1%, D3-RDP: 7.7%/0%. There is a significant change in OS/DFS in the D3-RDN from 2011-2013 to 2020-2022 (both P =0.046) and from 2014-2016 to 2020-2022 ( P =0.028 and P =0.005, respectively).

CONCLUSION

Our results indicate that surgery can achieve survival in most patients with central lymph node metastases by removing a personalized and anatomically defined D3 volume. The extent of mesenterectomy and the quality of surgery are paramount since a learning curve has demonstrated significantly improved survival over time despite the low number of patients. These results imply a place for the centralization of this patient group where feasible.

Visible Lymph Affluents in the D3 Volume: An MDCTA Pictorial Essay

BACKGROUND

There seems to be a gap in knowledge of the anatomy of mesenteric lymphatics between the superior mesenteric nodes and the intestinal trunk. To our knowledge, these central lymph vessels were not hitherto systematically searched for, described, or morphometrically analyzed. Our aim was to identify those vessels on the routine multidetector computerized tomography angiography (MDCTA), performed prior to right colectomy for cancer, with extended mesenterectomy, central vascular ligation, and D3 lymphadenectomy.

METHODS

A total of 420 MDCTA datasets were analyzed utilizing manual segmentation and 3D reconstruction, with the aid of image processing software Osirix, Mimics, and 3-matic. The 3D models and masks underwent a detailed topographic and morphometric analysis.

RESULTS

Significant vascular-like structures, having neither origin nor termination on the blood vessels, were noted in 18 cases (4.3%) in the D3 volume. The dimensions of visible lymph vessels varied, their mean diameter was 1.81 ± 0.61 mm, and the mean length was 38.07 ± 22.19 mm. In the vast majority of cases, the lymph vessels were situated in front of the superior mesenteric artery (SMA), coursing either longitudinally cranially (13 cases) or transversely/obliquely to the left (5 cases). In all cases but one, the lymph vessel passed at the left-hand side of the middle colic artery. As for the course shape, in seven cases, the lymph vessel appeared highly serpiginous.

CONCLUSIONS

The regular MDCTA can provide valuable information on mesenteric lymphatics and aid in surgical planning.