[Clinicopathological and molecular diagnostic features of early-onset gastric cancer: a study based on data from a single-center dedicated gastric cancer database].

Objective: To clarify the clinicopathological, especially molecular, features of early-onset gastric cancer with the aim of informing analysis of treatment strategies. Methods: In this retrospective case-control study, we examined data from a dedicated gastric cancer database in Zhongshan Hospital affiliated to Fudan University. The original cohort comprised 2506 patients with gastric cancer who had undergone gastrectomy in Zhongshan Hospital Fudan University from July 2020 to October 2021, including 198 with early-onset gastric cancer (aged ≤45 years) and 2,308 with non-early gastric cancer. We used a simple random sampling method to select 396 of the 2,308 patients aged >45 years (ratio of 1:2) as the control group and then compared molecular diagnostic data and clinicopathological features of the two groups. Results: The median age was 39 years in the early-onset gastric cancer group, while 66 years in the control group. The clinicopathological features of early-onset gastric cancer included female predominance (59.1% [117/198] vs. 27.8% [110/396], χ2=54.816, P<0.001), less comorbidity (32.3% [64/198] vs. 57.1% [226/396], χ2=32.355, P<0.001), poorer differentiation (93.9% [186/198] vs. 74.5% [295/396], χ2=30.777, P<0.001) and higher proportion of diffuse type (40.4% [80/198] vs. 15.9% [63/396], χ2=69.639, P<0.001), distant metastasis (7.1% [14/198] vs. 2.8% [11/396], χ2=6.034, P=0.014). Regarding treatment, distal gastrectomy was more commonly performed than proximal gastrectomy (55.1% [109/198] vs. 47.0% [186/396], 1.5% [3/198] vs. 8.3% [33/396], χ2=11.644, P=0.003). Family history of gastric cancer, TNM stage, tumor size, lymph node dissection, nerve invasion, nodes harboring metastases, range of lymph node dissection, digestive tract reconstruction procedure, implementation of laparoscopic surgery, combined resection, and preoperative treatment did not differ significantly between the two groups (all P>0.05). Molecular diagnosis showed there was a smaller percentage of mismatch repair deficiency in the early-onset gastric cancer than in the control group (1.0% [2/198] vs. 10.1% [40/396], χ2=16.301, P<0.001), and a higher rate of positivity for Claudin 18.2 (77.8% [154/198] vs. 53.0% [210/396], χ2=5.442,P<0.001). HER-2 and Epstein-Barr virus positivity rates did not differ significantly between the two groups. Conclusion: Early-onset gastric cancer is a distinct type of gastric cancer with a high degree of malignancy, and treatment targeting Claudin 18.2 may be effective.

[Efficacy of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy for gastric cancer].

Objective: To evaluate the efficacy of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy for gastric cancer in preventing duodenal stump leakage. Methods: A descriptive cohort study was conducted to retrospectively collect clinical data of 211 patients with gastric adenocarcinoma who underwent laparoscopic radical gastrectomy with Roux-en-Y or Billroth Ⅱ reconstruction and reinforcement on duodenal stump using laparoscopic single purse-string suture in Zhongshan Hospital of Fudan University between January 2013 and December 2016. Of 211 patients, 136 were male and 75 were female with mean age of (57.5±11.1)(24 to 87) years. Tumors locating at gastric upper 1/3, middle 1/3 and low 1/3 were found in 62, 68 and 81 patients respectively. Eighty-three cases underwent total gastrectomy, 128 underwent distal subtotal gastrectomy, 107 underwent Roux-en-Y reconstruction and 104 underwent Billroth II reconstruction. The procedure of reinforcement on duodenal stump using single purse-string suture during laparoscopic radical gastrectomy was as follows: (1) after cutting the duodenal stump to about 2.0 cm in length, use a 3-0 single-strand absorbable suture to make a muscle layer purse at a distance of 1.0 to 1.5 cm from the duodenal stump; (2) use the purse line to make a slipknot; (3) push the duodenum stump into the purse with a needle holder or grasper; (4) tighten the knot of the purse string, and then make 4 to 5 knots for reinforcement. Postoperative complications were defined and graded according to the Clavien-Dindo grading criteria, and the incidence of early complications was recorded. Clinicopathologic features and postoperative outcomes were analyzed. Results: All patients completed operations successfully. The mean time of laparoscopic single purse-string suture was (5.1±1.6) (3.6 to 10.2) minutes. Postoperative early complication occurred in 31 cases (14.7%), of whom 27 cases developed surgery-related complications (12.8%), including 7 cases (3.3%) of peritoneal infection, 6 (2.8%) of pancreatic leakage, 4 (1.9%) of wound infection, 4 (1.9%) of gastroplegia, 2 (0.9%) of peritoneal hemorrhage, 2 (0.9%) of intestinal obstruction, 2 (0.9%) of lymphatic leakage, and no duodenal stump leakage; while 4 cases (1.9%) developed internal non-surgical complication, including 3 cases (1.4%) of pulmonary infection and 1 (0.5%) of cardiovascular event. The patient with peritoneal hemorrhage was healed after re-operation and all other patients were discharged uneventfully after conservative treatment. Four cases (1.9%) developed complications beyond grade III a of Clavien-Dindo criteria. Conclusion: Reinforcement on duodenal stump using laparoscopic single purse-string suture during laparoscopic radical gastrectomy with Roux-en-Y or Billroth II reconstruction is simple and effective, and can prevent the risk of development of duodenal stump leakage.