Background: The anastomosis leak in colon resections is a crucial post-operative complication with significant morbidity and mortality. Methods: Forty (40) Wistar rats were allocated in two groups. In SHAM group only anastomosis was performed. In ILEUS group anastomosis was performed following one day of ileus. Animals in both groups were subdivided in two groups according to the day they were sacrificed, 4th or 8th post-operative day. A number of variables between the groups were estimated. Results: Body weight loss was higher following obstructive ileus on both days. Adhesion score in 4th and 8th post-operative day was higher in ILEUS1, ILEUS2 groups compared to SHAM1, SHAM2 groups respectively (p<0.001 for both). Neovascularization decreased following obstructive ileus compared to control on the 4th day (ILEUS1 vs. SHAM1, p=0.038). Bursting pressure was lower in ILEUS2 group than SHAM2 group (p<0.001). The number of fibroblasts decreased following obstructive ileus compared to control on the 4th and 8th day (ILEUS1 vs. SHAM1, p=0.001, ILEUS2 vs SHAM2, p=0.016). Hydroxyproline concentration was decreased in ILEUS2 group compared to SHAM2 group (p<0.001). Conclusions: The balance of collagenolysis and collagenogenesis plays a decisive role in the healing of anastomoses following bowel obstruction. Under those circumstances, anastomosis’ bursting pressure is reduced owning to decreased neovascularization, reduced fibroblast presence and lower hydroxyproline concertation. In our study, local inflammation, neocollagen concentration and collagenase activity were not associated with this adverse effect. However, further research should delineate the mechanisms of healing of colonic anastomoses and identify those factors that can improve our outcomes.

Background: This systematic review, using pairwise and network meta-analyses, aimed to compare the intraoperative, short-term, and long-term postoperative outcomes of minimally invasive surgery (MIS) and open surgery (OS) for the management of pancreatic neuroendocrine tumors (pNETs). Methods: Studies reporting on the effects of robotic, laparoscopic, and open surgery on pNETs published before November 2023 on PubMed, Scopus, and CENTRAL were analyzed. Results: Thirty-two studies with 5379 patients were included in this review, encompassing 2251 patients undergoing MIS (1334 laparoscopic, 508 robotic, and 409 unspecified MIS) and 3128 patients undergoing OS for pNETs management. Pairwise meta-analysis revealed that the MIS group had a significantly shorter length of hospital stay ((a low certainty of evidence), MD of −4.87 (−6.19 to −3.56)); less intraoperative blood loss ((a low certainty of evidence), MD of −108.47 (−177.47 to −39.47)); and decreased tumor recurrence ((a high certainty of evidence), RR of 0.46, 95% CI (0.33 to 0.63)). Subgroup analysis indicated a higher R0 resection rate and prolonged operative time for laparoscopic surgery than for OS. The network meta-analysis ranked the robotic approach as superior in terms of the length of hospital stay, followed by the laparoscopic and OS arms. Furthermore, it favored both MIS approaches over OS in terms of the R0 resection rate. No significant differences were found in severe postoperative complications, postoperative fistula formation, mortality, readmission, reoperation, or conversion rates. Conclusions: This review supports the safety of MIS for the treatment of pNETs. However, the varying certainty of evidence emphasizes the need for higher-quality studies.