Incidence of and risk factors for postoperative ileus between right and left laparoscopic colectomy using propensity-score-matched analysis: A retrospective multicenter study.

INSTRUCTION: In colon cancer, the incidence of postoperative ileus is reportedly higher for the right-side than for the left-side colon, but those studies included small numbers of subjects and contained several biases. Furthermore, risk factors for postoperative ileus remain unclear. METHODS: This multicenter study reviewed 1986 patients who underwent laparoscopic colectomy between 2016 and 2021 for right-side (n = 907) and left-side (n = 1079) colon cancer. After propensity score matching, 803 patients in each group were matched. RESULTS: Postoperative ileus occurred in 97 patients. Before matching, the proportion of female patients and median age were higher and frequency of preoperative stent insertion was lower with right colectomy (P < .001 each). After matching, the number of retrieved lymph nodes (17 vs 15, P < .001) and greater rates of undifferentiated adenocarcinoma (10.6% vs 5.1%, P < .001) and postoperative ileus (6.4% vs 3.2%, P = .004) were higher in right colectomy. Multivariate analysis revealed male gender (hazard ratio, 1.798; 95% confidence interval, 1.049-3.082; P = .32) and history of abdominal surgery (hazard ratio, 1.909; 95% confidence interval, 1.073-3.395; P = .027) as independent predictors of postoperative ileus in right-side colon cancer. CONCLUSION: This study revealed a higher risk of postoperative ileus after right colectomy with laparoscopic surgery. Male gender and history of abdominal surgery were risk factors for postoperative ileus after right colectomy.

Regeneration of the ureter using a scaffold-free live-cell structure created with the bio-three-dimensional printing technique.

Ureteral strictures, which can be caused by ureteral injury, radiation therapy, ureterolithiasis, urinary tract infections, and ureteral endometriosis, typically require ureteral reconstruction. Although tissue engineering, autologous alternative tissue transplantation, and surgical techniques applying various flaps have been carried out for ureteral regeneration, all with some success, each method has its advantages and disadvantages. As an alternative, we created the first artificial ureter structures using only live cells and grafted them into healthy rat ureters. Spheroids were created using normal human dermal fibroblasts and human umbilical vein endothelial cells and subsequently laminated using a bio-three-dimensional printer. After molding the laminated spheroids into tubular structures, the artificial ureters were transplanted into live rats. After 2-12 weeks, the animals were sacrificed and their gross and pathological features were examined. In the artificial ureteral lumen of rats with Grade 0-1 hydronephrosis, regeneration of the ureteral epithelium was observed, the thickness of which increased over the course of the experiment. Regeneration of the muscular layer was also observed, extending from the normal ureteral side toward the artificial ureter structure over time. However, complete regeneration was not observed at the end of 12 weeks. Although ureteral peristalsis was noted in all cases, it was weaker than expected. Therefore, we achieved short-segment ureteral regeneration using a cell-only structure. This finding suggests that by applying alternative strategies to this method, such as changing the cell type and composition, regeneration over the entire length of the ureter may be possible in the future. STATEMENT OF SIGNIFICANCE: Until now, ureteral regeneration techniques have been dominated by the use of high-molecular-weight compounds and autologous tissues, and there have been no reports of regeneration using structures made entirely of cells. This is the first report of ureteral regeneration using a tubular structure made from stacked spheroids. Although this study only attained short-segment ureteral regeneration, regeneration of the ureter over a much longer proportion of its length can be achieved in the future by applying other strategies, such as changing the cell type. This study provides a foundation to achieve the future goal of complete regeneration.

[A Trial of the Prevention of Postoperative Acute Exacerbation of Interstitial Pneumonia in Patients with Lung Cancer].

On preventing postoperative acute exacerbation (AE) of interstitial pneumonia (IP) in patients with lung cancer, the effect of administration of sivelestat sodium, steroids and erythromycin (EM) was assessed in 24 patients who was diagnosed as having IP and underwent surgery between April 2007 and October 2016. Oral administration of EM (400 mg) was started one week before the surgery, and methylprednisolone (125 mg) was administered intravenously at the time of anesthesia induction, postoperative day 1 and 2. Sivelestat sodium was administered intravenously at 4.8 mg/kg/day during the surgery, which was continued for 3-5 days. AEs occurred in two cases (8.3%). One patient developed AEs on postoperative day 5 and died in the hospital on postoperative day 76. The other patient developed AEs on postoperative day 38 and died in the hospital on postoperative day 43. In addition to the perioperative administration of steroids and EM in patients with lung cancer and IP, intraoperative administration of sivelestat sodium was suggested to be safe and to potentially prevent AEs.