[Incidence of postoperative complications in Chinese patients with gastric or colorectal cancer based on a national, multicenter, prospective, cohort study]

Objective: To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications. Methods: This was a national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo grading criteria. The incidence of postoperative complications of different grades are presented as bar charts. Independent risk factors for occurrence of postoperative complications were identified by multifactorial unconditional logistic regression. Results: The study cohort comprised 3926 patients with gastric or colorectal cancer, 657 (16.7%) of whom had a total of 876 postoperative complications. Serious complications (Grade III and above) occurred in 4.0% of patients (156/3926). The rate of Grade V complications was 0.2% (7/3926). The cohort included 2271 patients with gastric cancer with a postoperative complication rate of 18.1% (412/2271) and serious complication rate of 4.7% (106/2271); and 1655 with colorectal cancer, with a postoperative complication rate of 14.8% (245/1655) and serious complication rate of 3.0% (50/1655). The incidences of anastomotic leakage in patients with gastric and colorectal cancer were 3.3% (74/2271) and 3.4% (56/1655), respectively. Abdominal infection was the most frequently occurring complication, accounting for 28.7% (164/572) and 39.5% (120/304) of postoperative complications in patients with gastric and colorectal cancer, respectively. The most frequently occurring grade of postoperative complication was Grade II, accounting for 65.4% (374/572) and 56.6% (172/304) of complications in patients with gastric and colorectal cancers, respectively. Multifactorial analysis identified (1) the following independent risk factors for postoperative complications in patients in the gastric cancer group: preoperative comorbidities (OR=2.54, 95%CI: 1.51-4.28, P<0.001), neoadjuvant therapy (OR=1.42, 95%CI:1.06-1.89, P=0.020), high American Society of Anesthesiologists (ASA) scores (ASA score 2 points:OR=1.60, 95% CI: 1.23-2.07, P<0.001, ASA score ≥3 points:OR=0.43, 95% CI: 0.25-0.73, P=0.002), operative time >180 minutes (OR=1.81, 95% CI: 1.42-2.31, P<0.001), intraoperative bleeding >50 mL (OR=1.29,95%CI: 1.01-1.63, P=0.038), and distal gastrectomy compared with total gastrectomy (OR=0.65,95%CI: 0.51-0.83, P<0.001); and (2) the following independent risk factors for postoperative complications in patients in the colorectal cancer group: female (OR=0.60, 95%CI: 0.44-0.80, P<0.001), preoperative comorbidities (OR=2.73, 95%CI: 1.25-5.99, P=0.030), neoadjuvant therapy (OR=1.83, 95%CI:1.23-2.72, P=0.008), laparoscopic surgery (OR=0.47, 95%CI: 0.30-0.72, P=0.022), and abdominoperineal resection compared with low anterior resection (OR=2.74, 95%CI: 1.71-4.41, P<0.001). Conclusion: Postoperative complications associated with various types of infection were the most frequent complications in patients with gastric or colorectal cancer. Although the risk factors for postoperative complications differed between patients with gastric cancer and those with colorectal cancer, the presence of preoperative comorbidities, administration of neoadjuvant therapy, and extent of surgical resection, were the commonest factors associated with postoperative complications in patients of both categories.

[A multicenter retrospective study on the efficacy of different anti-reflux reconstruction methods after proximal gastrectomy for gastric cancer]

Objective: To examine the clinical efficacy of 3 anti-reflux methods of digestive tract reconstruction after proximal gastrectomy for gastric cancer. Methods: The clinical data and follow-up data of gastric cancer patients who underwent anti-reflux reconstruction after proximal gastrectomy in 11 medical centers of China from September 2016 to August 2021 were retrospectively collected, including 273 males and 65 females, aging of (63±10) years (range: 28 to 91 years). Among them, 159 cases were performed with gastric tube anastomosis (GTA), 107 cases with double tract reconstruction (DTR), and 72 cases with double-flap technique (DFT), respectively. The duration of operation, length of postoperative hospital stay and early postoperative complications (referring to Clavien-Dindo classification) of different anti-reflux reconstruction methods were assessed. Body mass index, hemoglobin and albumin were used to reflect postoperative nutritional status. Reflux esophagitis was graded according to Los Angeles criteria based on the routinely gastroscopy within 12 months after surgery. The postoperative quality of life (QoL) was evaluated by Visick score system. The ANOVA analysis, Kruskal-Wallis rank sum test, χ² test and Fisher's exact test were used for comparison between multiple groups, and further comparison among groups were performed with LSD, Tamhane's test or Bonferroni corrected χ² test. The mixed effect model was used to compare the trends of Body mass index, hemoglobin and albumin over time among different groups. Results: The operation time of DFT was significantly longer than that of GTA and DTR ((352±63) minutes vs. (221±66) minutes, (352±63) minutes vs. (234±61) minutes, both P<0.01). The incidence of early complications with Clavien-Dindo grade Ⅱ to Ⅴ in GTA, DFT and DTR groups was 17.0% (27/159), 9.7% (7/72) and 10.3% (11/107), respectively, without significant difference among these three groups (χ²=3.51, P=0.173). Body mass index decreased more significantly in GTA than DFT group at 6 and 12 months after surgery (mean difference=1.721 kg/m², P<0.01; mean difference=2.429 kg/m², P<0.01). body mass index decreased significantly in DTR compared with DFT at 12 months after surgery (mean difference=1.319 kg/m², P=0.027). There was no significant difference in hemoglobin or albumin fluctuation between different reconstruction methods perioperative. The incidence of reflux esophagitis one year after surgery in DTR group was 12.9% (4/31), which was lower than that in DFT (45.9% (17/37), χ²=8.63, P=0.003). Follow-up of postoperative quality of life showed the incidence of Visick grade 2 to 4 in DFT group was lower than that in GTA group (10.4% (7/67) vs. 34.6% (27/78), χ²=11.70, P=0.018), while there was no significant difference between DFT and DTR group (10.4% (7/67) vs. 22.2% (8/36, P>0.05). Conclusions: Compared with GTA and DTR, DFT is more time-consuming, but there is no significant difference in early complications among three methods. DFT reconstruction is more conducive to maintain postoperative nutritional status and improve QoL, especially compared with GTA. The risk of reflux esophagitis after DTR reconstruction is lower than that of DFT.

Cloning and transformation analysis of isoflavone synthase gene into Minshan Trifolium pratense

The aim of this study was to clone the isoflavone synthase (IFS) gene and establish the recombinant Minshan Trifolium pratense. The IFS gene was cloned from the callus of Minshan T. pratense using reverse transcription-polymerase chain reaction. The plant expression vector pRI101-AN-IFS was constructed and introduced into Agrobacterium tumefaciens strain LBA4404, and then screened under cephalosporin. IFS expression was detected by reverse transcription-polymerase chain reaction. The IFS gene was cloned successfully. Sequence analysis indicated that IFS gene had high homology with similar genes from other plants. The IFS-overexpressing callus was obtained by introducing the LBA4404-harboring IFS-pRI101-AN-IFS vector into T. pratense calluses.