[Meta-analysis of laparoscopic versus open surgery for palliative resection of the primary tumor in stage IV colorectal cancer].

Objective: To systematically evaluate the safety and efficacy of laparoscopic versus open surgery for palliative resection of the primary tumor in stage IV colorectal cancer. Methods: The databases of CNKI, Wanfang, VIP, PubMed, EMBASE and Cochrane Library were searched to retrieve randomized controlled trials (RCT) or clinical controlled trials (CCT) comparing laparoscopic surgery with open surgery for palliative resection of the primary tumor in stage IV colorectal cancer published from January 1991 to May 2019. Chinese search terms included "colorectum/colon/rectum" , "cancer/malignant tumor" , "laparoscopy" , "metastasis" , " IV" ; English search terms included "laparoscop*" , "colo*" , "rect*" , "cancer/tumor/carcinoma/neoplasm" , " IV" , "metasta*" . Inclusion criteria: (1) RCT or CCT, with or without allocation concealment or blinding; (2) patients with stage IV colorectal cancer that was diagnosed preoperatively and would receive resection of the primary tumor; (3) the primary tumor that was palliatively resected by laparoscopic or open procedure. Exclusion criteria: (1) no valid data available in the literature; (2) single study sample size ≤20; (3) subjects with colorectal benign disease; (4) metastatic resection or lymph node dissection was performed intraoperatively in an attempt to perform radical surgery; (5) duplicate publication of the literature. Two researchers independently evaluated the quality of the included studies. In case of disagreement, the evaluation was performed by discussion or a third researcher was invited to participate. The data were extracted from the included studies, and the Cochrane Collaboration RevMan 5.1.0 version software was used for this meta-analysis. Results: Four CCTs with a total of 864 patients were included in this study, including 216 patients in the laparoscopic group and 648 patients in the open group. Compared with the open group, except for longer operation time (WMD=37.60, 95% CI: 26.11 to 49.08, P<0.05), laparoscopic group had less intraoperative blood loss (WMD=-74.89, 95% CI: -144.78 to -5.00, P<0.05), earlier first flatus and food intake after surgery (WMD=-1.00, 95% CI: -1.12 to -0.87, P<0.05; WMD=-1.61, 95%CI: -2.16 to -1.06, P<0.05), shorter hospital stay (WMD=-2.01, 95% CI: -2.21 to -1.80, P<0.05) and lower morbidity of postoperative complication (OR=0.52, 95% CI: 0.35 to 0.77, P<0.05). However, no significant differences were found in time to start postoperative chemotherapy, postoperative chemotherapy rate, and mortality (P > all 0.05). Conclusion: Laparoscopic surgery for palliative resection of the primary tumor is safe and feasible to enhance recovery after surgery by promoting postoperative bowel function recovery, shortening hospital stay and reducing postoperative complication in stage IV colorectal cancer.

Acute insulin resistance following surgical trauma in rats.

OBJECTIVE: To unravel the possible mechanism of acute posttraumatic insulin resistance in rats. METHODS: Resection of small intestine was performed to establish the surgical trauma model. The blood glucose and serum insulin level were detected and the HOMA index was calculated. The Hyperinsulinemic-euglycemic clamp was performed to investigate the glucose disposal rate by peripheral tissue. The content and phosphorylation state of IRS-1, p85 of PI3-K and PKB/Akt in skeletal muscle were measured respectively. Finally, the [3H] labeled glucose uptake experiment was carried out. RESULTS: The blood glucose elevated significantly after resection of small intestine in rats. The level of serum insulin decreased during the first 30 min after operation but elevated in the following time. The HOMA-IR in trauma group was significantly greater than control group; however the HOMA-ß in trauma group was less than control group. The glucose disposal rate was decreased 49% after operation. The p-IRS-1(Ser307) was significantly enhanced 95% after trauma while the p-IRS-1 (Tyr612) was attenuated by 38%. The phosphorylation of its downstream target, p-PKB/Akt(Ser473) was attenuated by 48%. Accordingly, the glucose uptaken by skeletal muscle was significantly decreased in trauma group. CONCLUSION: We demonstrated the posttraumatic insulin resistance occurred soon after surgical trauma in rats. The level of insulin was relatively insufficient because of the decreased sensitivity in peripheral tissue. Trauma induced Ser phosphorylation instead of Tyr phosphorylation eliminated the ability of IRS-1 to activate downstream effector molecules such as PKB/Akt and resulted in severe impairment of insulin signal transduction and glucose transport in skeletal muscle.