Background and Aims:The completeness of lymph node dissection in laparoscopic radical gastrectomy for gastric cancer directly affects postoperative patient prognosis.Indocyanine green(ICG)fluorescence-guided navigation,as an emerging auxiliary technique,enables real-time visualization of lymphatic drainage pathways and enhances surgical precision.This study was performed to evaluate the impact of ICG fluorescence navigation on lymph node dissection,positive lymph node detection,and patient prognosis during laparoscopic D2 radical gastrectomy for gastric cancer.Methods:The clinical data of 168 patients who underwent laparoscopic radical gastrectomy at Zhangzhou Affiliated Hospital of Fujian Medical University from January 2021 to December 2022 were retrospectively analyzed.Among them,51 patients received ICG-guided surgery(ICG group),and 117 underwent conventional surgery(non-ICG group).Perioperative variables,extent of lymph node dissection,positive lymph node detection efficiency,and postoperative survival outcomes were compared between the two groups.Results:There were no statistically significant differences between the two groups in baseline clinicopathologic characteristics,as well as operative time,intraoperative blood loss,postoperative recovery,and incidence of surgical complications(all P>0.05).The ICG group had a significantly higher mean number of lymph nodes dissected than the non-ICG group(48.62 vs.37.20,P<0.001),with a greater proportion of patients achieving≥30 nodes dissected(92.16％vs.69.23％,P=0.001).Stratified analysis showed a significantly higher number of dissected lymph nodes in the ICG group at D2 stations,the supra-pancreatic region(stations 7,8,9,11),in total gastrectomy,T3-4 stage,and stage Ⅲ patients(all P<0.01).In the ICG group,the number and positivity rate of fluorescent lymph nodes were significantly higher than those of non-fluorescent nodes(30.31 vs.17.36;2.03 vs.0.94,both P<0.05).The diagnostic sensitivity of ICG fluorescence imaging for positive lymph nodes was 68.4％,with a negative predictive value of 94.6％for non-fluorescent nodes.No significant differences were observed between the two groups in terms of adjuvant therapy,overall survival(HR=0.737,P=0.471),or disease-free survival(HR=0.502,P=0.089).Conclusion:ICG-guided navigation in laparoscopic radical gastrectomy for gastric cancer is safe and significantly improves lymph node yield,particularly in the supra-pancreatic region,total gastrectomy,and advanced-stage patients.It also enhances positive node detection.However,no survival benefit has been observed in the short term.Further multicenter studies with long-term follow-up are warranted to confirm its clinical value and optimize intraoperative navigation strategies.

Objective:To investigate the impact of neoadjuvant immunotherapy combined with chemotherapy on the safety and efficacy of radical resection in patients with cT3-4NxM0 gastric cancer.Methods:A retrospective cohort study method was used. The clinicopathological data of 515 patients who underwent radical gastrectomy after neoadjuvant treatment at Second Department of Gastric Surgery,Fudan University Shanghai Cancer Center and Department of Gastric Surgery,Zhangzhou Hospital Affiliated to Fujian Medical University from January 2020 to June 2023 were collected. Among them,379 patients received neoadjuvant chemotherapy alone(chemotherapy group),and 136 patients received neoadjuvant immunotherapy combined with chemotherapy(immunotherapy group). There were 382 males and 133 females,with an age of (58.4±10.9)years(range:26 to 85 years). To reduce the influence of potential confounding factors,a 1∶1 propensity score matching method was adopted,and the clamp value was 0.02. The peri-operative safety,imaging and postoperative pathological tumor regression,and prognosis were compared by independent sample t-test, Mann-Whitney U test, χ 2 test or Fisher exact probability method between the two groups. The Kaplan-Meier method was used to draw survival curves, and the differences between groups were compared by Log-rank test. Results:After matching, there were 101 patients in each of the chemotherapy group and the immunotherapy group. The baseline data of the patients in the two groups were evenly distributed (all P>0.05). According to the RECIST 1.1 criteria, the complete response rate (11.9% (12/101) vs. 4.0% (4/101)), partial response rate(68.3%(69/101) vs. 53.4%(54/101)), stable disease rate (17.8%(18/101) vs. 39.6%(40/101)) and disease progression rate (2.0%(2/101) vs. 3.0%(3/101)) between the immunotherapy group and the chemotherapy group were no statistical defferences ( χ2=14.374, P=0.002), and objective response rate (80.2%(81/101) vs. 57.4%(58/101), χ2=12.203, P<0.01) in the immunotherapy group was higher than that in the chemotherapy group. The results of postoperative pathological examination showed that the immunotherapy group had a higher complete response rate (16.8%(17/101) vs. 6.9% (7/101), χ2=4.728, P=0.030) and major pathological response rate (42.6%(43/101) vs. 23.8% (24/101), χ2=8.062, P=0.005). For the two groups, the operation time (175.0(76.0)minutes vs. 160.0 (30.0)minutes, Z=-0.059, P=0.953), intraoperative blood loss (110.0 (150.0)ml vs. 100.0 (120.0)ml, Z=-0.370, P=0.712), overall incidence of postoperative complications (20.8%(21/101) vs. 18.8%(19/101), χ2=0.125, P=0.724) and incidence of severe complications (5.0%(5/101) vs. 3.0%(3/101), χ2=0.130, P=0.718) were comparable. The median follow-up time of all patients was 46 months(range: 19 to 61 months). The 3-year overall survival rate (63.2% vs. 54.4%, P=0.035) and progression-free survival rate (59.1% vs. 45.6%, P=0.022) of the immunotherapy group were higher than those of the chemotherapy group. Meanwhile, there were no statistically significant differences in the incidence of neoadjuvant-treatment-related adverse events (48.5%(49/101) vs. 40.6% (41/101), χ2=1.283, P=0.411) and the incidence of severe adverse reactions of grade 3 or above (13.9% (14/101) vs. 10.9% (11/101), χ2=0.257, P=0.522) between the two groups. Conclusion:Neoadjuvant immunotherapy combined with chemotherapy can significantly improve the imaging and postoperative pathological tumor response rates and 3-year survival rate of patients with locally advanced gastric cancer,without increasing the incidence of postoperative complications and neoadjuvant treatment-related adverse event.

Objective:To explore the optimal age cutoff for diagnosis and the prognosis of early-onset gastric cancer in young patients.Methods:Clinicopathological data of patients with gastric adenocarcinoma aged ≤45 years who had undergone radical gastrectomy in the Department of Gastric Surgery, Fudan University Shanghai Cancer Center from January 2013 to December 2018 were retrospectively collected. Patients with distant metastases, other malignant tumors, combined organ resection, gastric stump cancer, positive margin, and incomplete clinical or follow-up data were excluded. X-tile software analysis of the actual overall survival of the collected cases yielded an optimal cut-off of 32 years. Accordingly, the enrolled cases were divided into an early-onset young group (age ≤32 years) and young adult group (age >32 years). Clinicopathological characteristics, long-term survival, and postoperative recurrence were compared between the two groups. Univariate and multivariate analyses were performed using the Cox proportional hazards model to identify the factors affecting the prognosis of young patients with gastric cancer.Results:The study cohort comprised 462 patients, including 256 (55.4%) women, 419 (90.7%) with middle and lower gastric cancers, and 343 (74.2%) with poorly differentiated tumors. There were 101 patients in the early-onset young group and 361 in the young adult group. These groups did not differ significantly in terms of sex, body mass index, tumor location, tumor size, surgical procedure, neurovascular invasion, or tumor stage (all P>0.05). The proportion of patients with poorly differentiated tumors in the early-onset young group was significantly higher than that in the young adult group (89.1%[90/101] vs. 70.1%[253/361], χ 2=15.26, P<0.001). All study patients completed 5 years of follow-up, the median duration of which was 101 months (61-133 months). Death or tumor recurrence occurred in 151 patients (32.7%), in 118 of whom the sites of recurrence and metastasis could be identified, 38 in the early-onset young group and 80 in the young adult group. Fifty-five (46.6%) patients developed peritoneal metastases and 40 (33.9%) hematogenous metastases. In the early-onset young group, 20 patients developed peritoneal metastases, 11 hematogenous metastases, five distant lymph node metastases, and two local recurrence. In the young adult group, 35 patients developed peritoneal metastases, 29 hematogenous metastases, six local recurrences, and 10 distant lymph node metastases. The 5-year overall survival and disease-free survival rates were significantly higher in the young adult group than in the early-onset young group (73.7% vs. 57.4%, P=0.002 and 70.6% vs. 55.4%, P=0.004, respectively). Cox multivariate analysis showed that age >32 years (HR=0.63, 95%CI: 0.43-0.90, P=0.012) was an independent protective factor for overall survival, whereas later N stage (HR=1.67, 95%CI:1.09-2.57, P=0.018) was an independent risk factor for overall survival after surgery ( P<0.05). Age >32 years (HR=0.60, 95%CI: 0.41-0.86, P=0.006) was also an independent protective factor for disease-free survival, whereas later N stage was an independent risk factor (HR=1.69, 95%CI: 1.08-2.64, P=0.021). Conclusion:Young patients with early-onset gastric cancer aged ≤32 years have worse tumor differentiation and prognosis.

Objective:To investigate the impact of bedside ultrasound-guided hyperthermic intraperitoneal chemotherapy (HIPEC) after laparoscopic gastric cancer surgery on the prognosis of patients with only positive peritoneal lavage cytology (CY+) and no other distant metastases.Methods:The clinicopathological data of 49 patients with only positive peritoneal lavage cytology who underwent laparoscopic gastrectomy and D2 lymph node dissection from December 2017 to December 2022 were retrospectively analyzed. The patients were divided into the HIPEC group (27 cases) and the non-HIPEC group (22 cases) based on whether they received postoperative bedside ultrasound-guided HIPEC. The patterns of postoperative recurrence and metastasis and the 3-year survival rates were compared between the two groups. Univariate and multivariate analyses using the Cox proportional hazards model were conducted to determine the prognostic factors.Results:There was no statistically significant difference in all baseline clinicopathological data between the two groups ( P>0.05); the median follow-up time for all patients was 31 months (ranging from 13 to 73 months), and the overall recurrence rate for all patients was 55.1% (27/49). Among them, 12 cases (24.5%) had peritoneal metastasis, 7 cases (14.3%) had hematogenous recurrence, 5 cases (10.2%) had distant lymph node metastasis, and 3 cases (6.1%) had local recurrence. The overall recurrence rates of patients in the HIPEC group and the non-HIPEC group were 51.8% (14/27) and 59.1% (13/22), respectively. There was no statistically significant difference (χ 2=0.26, P=0.612). The peritoneal metastasis rate of patients in the HIPEC group was 18.5% (5/27), which was lower than that of the non-HIPEC group at 31.8% (7/22). However, there was no statistically significant difference (χ 2=1.16, P=0.282). The proportions of local recurrence, hematogenous metastasis, and distant lymph node metastasis were comparable between the two groups (all P>0.05). The cumulative 3-year recurrence rates of the two groups were similar (70.7% vs. 71.3%, P=0.266). In the HIPEC group, the 3-year overall survival rate was 61.1%, which was significantly higher than that of the non-HIPEC group (31.5%). The difference was statistically significant ( P=0.014). The disease-free progression survival rates of the two groups were 29.3% and 28.7% respectively, and there was no statistically significant difference between them ( P=0.266). Cox multivariate analysis showed that no postoperative HIPEC (HR=5.21, 95%CI:1.90-14.31, P=0.001), poor tumor differentiation (HR=3.78, 95%CI:1.07-13.26, P=0.038), and later N stage (HR=6.18, 95%CI:1.39-7.59, P=0.017) were independent risk factors for the overall survival rate after surgery ( P<0.05). Later N stage (HR=3.67, 95%CI:1.07-12.55, P=0.038) was an independent risk factor for the disease-free progression survival rate after surgery ( P<0.05). Conclusion:Bedside ultrasound-guided HIPEC after laparoscopic gastrectomy and D2 lymph node dissection can improve the overall survival of CY+ gastric cancer patients.

Objective:To investigate the influencing factors and prognosis of early recurrence after gastrectomy for gastric cancer.Methods:The retrospective cohort study was conducted. The clinicopathological data of 2 078 patients who underwent gastrectomy for gastric cancer at six medical centers across China, including Fudan University Shanghai Cancer Center et al, between January 2012 and June 2023 were collected. There were 1 449 males and 629 females, aged (59±11) years. Patients were classified as early recurrence and late recurrence based on the time of post-operative recurrence. Observation indicators: (1) comparison of clinicopathological characteristics between gastric cancer patients with different recurrence types; (2) recurrence and metastasis of tumor; (3) survival of patients after postoperative recurrence of gastric cancer; (4) analysis of influencing factors for early recurrence after gastrectomy for gastric cancer. Comparison of measurement data with normal distribution between groups was conducted using the independent sample t test. Comparison of measurement data with skewed distribution between groups was conducted using the Mann-Whitney U test. Comparison of count data between groups was conducted using the chi-square test. Comparison of ordinal data between groups was conducted using the rank sum test. Multivariate analysis was conducted using the Logistic regression model. Kaplan-Meier method was used to calculate survival rate and plot survival curve, and Log-rank test was used for survival analysis. Results:(1) Comparison of clinicopathological characteristics between gastric cancer patients with different recurrence types. Among the 2 078 patients, 1 452 cases had early recurrence and 626 cases had late recurrence. There were significant differences in preoperative carcinoembryonic antigen, preoperative CA19-9, preoperative CA72-4, preoperative albumin, tumor diameter, neoadjuvant therapy, R 0 resection, combined organ resection, scope of gastric resection, nerve and vessel infiltration, degree of tumor differentiation, pathological N staging, pathological TNM staging between early and late recurrence patients ( P<0.05). (2) Recurrence and metastasis of tumor. Among the 2 078 patients, 200 cases had local recurrence, 1 213 cases had hematogenous metastases, 392 cases had distant lymph node metastases, and 731 cases had peritoneal metastases. Among the 1 452 early recurrence patients, 142 cases had local recurrence, 834 cases had hematogenous metastases, 289 cases had distant lymph node metastases, and 507 cases had peritoneal metastases. Among the 626 late recurrence patients, 58 cases had local recurrence, 379 cases had hematogenous metastases, 103 cases had distant lymph node metastases, and 224 cases had peritoneal metastases. One patient may have multiple forms of recurrence and metastasis. There was no significant difference in the above indica-tors between early and late recurrence patients ( χ2=0.13, 1.74, 3.40, 0.14, P>0.05). (3) Survival of patients after postoperative recurrence of gastric cancer. All 2 078 patients were followed up until death after recurrence, with a follow-up time of 31(range, 9?147)months. The 1-, 2-, 3-, and 5-year overall survival rates after recurrence were 33.5%, 17.2%, 10.1%, and 3.3% in early recurrence patients, versus 44.2%, 21.6%, 12.8%, and 5.8% in late recurrence patients, respectively, showing a significant difference in overall survival after recurrence between the two groups ( hazard ratio=0.84, 95% confidence interval as 0.76?0.92, P<0.05). (4) Analysis of influencing factors for early recurrence after gastrectomy for gastric cancer. Results of multivariate analysis showed that combined organ resection, total gastrectomy, pathological TNM staging as stage Ⅲ were independent risk factors for early recurrence after gastrectomy for gastric cancer ( odds ratio=1.31, 1.32, 1.34, 95% confidence interval as 1.01?1.70, 1.06?1.65, 1.05?1.71, P<0.05) and normal preoperative tumor markers, neoadjuvant therapy, R 0 resection were independent protective factors for early recurrence ( odds ratio=0.61, 0.50, 0.38, 95% confidence interval as 0.49?0.76, 0.35?0.72, 0.25?0.58, P<0.05). Conclusions:Compared with patients with late recurrence after gastric cancer surgery, patients with early recurrence have a poor prognosis, in which liver metastases is more common. Combine organ resection, total gastrectomy, pathological TNM staging as stage Ⅲ are independent risk factors for early recurrence, and normal preoperative tumor markers, neoadjuvant therapy, R 0 resection are independent protective factors for early recurrence after gastrectomy for gastric cancer.

Background and Aims:The completeness of lymph node dissection in laparoscopic radical gastrectomy for gastric cancer directly affects postoperative patient prognosis.Indocyanine green(ICG)fluorescence-guided navigation,as an emerging auxiliary technique,enables real-time visualization of lymphatic drainage pathways and enhances surgical precision.This study was performed to evaluate the impact of ICG fluorescence navigation on lymph node dissection,positive lymph node detection,and patient prognosis during laparoscopic D2 radical gastrectomy for gastric cancer.Methods:The clinical data of 168 patients who underwent laparoscopic radical gastrectomy at Zhangzhou Affiliated Hospital of Fujian Medical University from January 2021 to December 2022 were retrospectively analyzed.Among them,51 patients received ICG-guided surgery(ICG group),and 117 underwent conventional surgery(non-ICG group).Perioperative variables,extent of lymph node dissection,positive lymph node detection efficiency,and postoperative survival outcomes were compared between the two groups.Results:There were no statistically significant differences between the two groups in baseline clinicopathologic characteristics,as well as operative time,intraoperative blood loss,postoperative recovery,and incidence of surgical complications(all P>0.05).The ICG group had a significantly higher mean number of lymph nodes dissected than the non-ICG group(48.62 vs.37.20,P<0.001),with a greater proportion of patients achieving≥30 nodes dissected(92.16％vs.69.23％,P=0.001).Stratified analysis showed a significantly higher number of dissected lymph nodes in the ICG group at D2 stations,the supra-pancreatic region(stations 7,8,9,11),in total gastrectomy,T3-4 stage,and stage Ⅲ patients(all P<0.01).In the ICG group,the number and positivity rate of fluorescent lymph nodes were significantly higher than those of non-fluorescent nodes(30.31 vs.17.36;2.03 vs.0.94,both P<0.05).The diagnostic sensitivity of ICG fluorescence imaging for positive lymph nodes was 68.4％,with a negative predictive value of 94.6％for non-fluorescent nodes.No significant differences were observed between the two groups in terms of adjuvant therapy,overall survival(HR=0.737,P=0.471),or disease-free survival(HR=0.502,P=0.089).Conclusion:ICG-guided navigation in laparoscopic radical gastrectomy for gastric cancer is safe and significantly improves lymph node yield,particularly in the supra-pancreatic region,total gastrectomy,and advanced-stage patients.It also enhances positive node detection.However,no survival benefit has been observed in the short term.Further multicenter studies with long-term follow-up are warranted to confirm its clinical value and optimize intraoperative navigation strategies.

Objective:To explore the optimal age cutoff for diagnosis and the prognosis of early-onset gastric cancer in young patients.Methods:Clinicopathological data of patients with gastric adenocarcinoma aged ≤45 years who had undergone radical gastrectomy in the Department of Gastric Surgery, Fudan University Shanghai Cancer Center from January 2013 to December 2018 were retrospectively collected. Patients with distant metastases, other malignant tumors, combined organ resection, gastric stump cancer, positive margin, and incomplete clinical or follow-up data were excluded. X-tile software analysis of the actual overall survival of the collected cases yielded an optimal cut-off of 32 years. Accordingly, the enrolled cases were divided into an early-onset young group (age ≤32 years) and young adult group (age >32 years). Clinicopathological characteristics, long-term survival, and postoperative recurrence were compared between the two groups. Univariate and multivariate analyses were performed using the Cox proportional hazards model to identify the factors affecting the prognosis of young patients with gastric cancer.Results:The study cohort comprised 462 patients, including 256 (55.4%) women, 419 (90.7%) with middle and lower gastric cancers, and 343 (74.2%) with poorly differentiated tumors. There were 101 patients in the early-onset young group and 361 in the young adult group. These groups did not differ significantly in terms of sex, body mass index, tumor location, tumor size, surgical procedure, neurovascular invasion, or tumor stage (all P>0.05). The proportion of patients with poorly differentiated tumors in the early-onset young group was significantly higher than that in the young adult group (89.1%[90/101] vs. 70.1%[253/361], χ 2=15.26, P<0.001). All study patients completed 5 years of follow-up, the median duration of which was 101 months (61-133 months). Death or tumor recurrence occurred in 151 patients (32.7%), in 118 of whom the sites of recurrence and metastasis could be identified, 38 in the early-onset young group and 80 in the young adult group. Fifty-five (46.6%) patients developed peritoneal metastases and 40 (33.9%) hematogenous metastases. In the early-onset young group, 20 patients developed peritoneal metastases, 11 hematogenous metastases, five distant lymph node metastases, and two local recurrence. In the young adult group, 35 patients developed peritoneal metastases, 29 hematogenous metastases, six local recurrences, and 10 distant lymph node metastases. The 5-year overall survival and disease-free survival rates were significantly higher in the young adult group than in the early-onset young group (73.7% vs. 57.4%, P=0.002 and 70.6% vs. 55.4%, P=0.004, respectively). Cox multivariate analysis showed that age >32 years (HR=0.63, 95%CI: 0.43-0.90, P=0.012) was an independent protective factor for overall survival, whereas later N stage (HR=1.67, 95%CI:1.09-2.57, P=0.018) was an independent risk factor for overall survival after surgery ( P<0.05). Age >32 years (HR=0.60, 95%CI: 0.41-0.86, P=0.006) was also an independent protective factor for disease-free survival, whereas later N stage was an independent risk factor (HR=1.69, 95%CI: 1.08-2.64, P=0.021). Conclusion:Young patients with early-onset gastric cancer aged ≤32 years have worse tumor differentiation and prognosis.

Objective:To investigate the impact of bedside ultrasound-guided hyperthermic intraperitoneal chemotherapy (HIPEC) after laparoscopic gastric cancer surgery on the prognosis of patients with only positive peritoneal lavage cytology (CY+) and no other distant metastases.Methods:The clinicopathological data of 49 patients with only positive peritoneal lavage cytology who underwent laparoscopic gastrectomy and D2 lymph node dissection from December 2017 to December 2022 were retrospectively analyzed. The patients were divided into the HIPEC group (27 cases) and the non-HIPEC group (22 cases) based on whether they received postoperative bedside ultrasound-guided HIPEC. The patterns of postoperative recurrence and metastasis and the 3-year survival rates were compared between the two groups. Univariate and multivariate analyses using the Cox proportional hazards model were conducted to determine the prognostic factors.Results:There was no statistically significant difference in all baseline clinicopathological data between the two groups ( P>0.05); the median follow-up time for all patients was 31 months (ranging from 13 to 73 months), and the overall recurrence rate for all patients was 55.1% (27/49). Among them, 12 cases (24.5%) had peritoneal metastasis, 7 cases (14.3%) had hematogenous recurrence, 5 cases (10.2%) had distant lymph node metastasis, and 3 cases (6.1%) had local recurrence. The overall recurrence rates of patients in the HIPEC group and the non-HIPEC group were 51.8% (14/27) and 59.1% (13/22), respectively. There was no statistically significant difference (χ 2=0.26, P=0.612). The peritoneal metastasis rate of patients in the HIPEC group was 18.5% (5/27), which was lower than that of the non-HIPEC group at 31.8% (7/22). However, there was no statistically significant difference (χ 2=1.16, P=0.282). The proportions of local recurrence, hematogenous metastasis, and distant lymph node metastasis were comparable between the two groups (all P>0.05). The cumulative 3-year recurrence rates of the two groups were similar (70.7% vs. 71.3%, P=0.266). In the HIPEC group, the 3-year overall survival rate was 61.1%, which was significantly higher than that of the non-HIPEC group (31.5%). The difference was statistically significant ( P=0.014). The disease-free progression survival rates of the two groups were 29.3% and 28.7% respectively, and there was no statistically significant difference between them ( P=0.266). Cox multivariate analysis showed that no postoperative HIPEC (HR=5.21, 95%CI:1.90-14.31, P=0.001), poor tumor differentiation (HR=3.78, 95%CI:1.07-13.26, P=0.038), and later N stage (HR=6.18, 95%CI:1.39-7.59, P=0.017) were independent risk factors for the overall survival rate after surgery ( P<0.05). Later N stage (HR=3.67, 95%CI:1.07-12.55, P=0.038) was an independent risk factor for the disease-free progression survival rate after surgery ( P<0.05). Conclusion:Bedside ultrasound-guided HIPEC after laparoscopic gastrectomy and D2 lymph node dissection can improve the overall survival of CY+ gastric cancer patients.

Objective:To investigate the influencing factors and prognosis of early recurrence after gastrectomy for gastric cancer.Methods:The retrospective cohort study was conducted. The clinicopathological data of 2 078 patients who underwent gastrectomy for gastric cancer at six medical centers across China, including Fudan University Shanghai Cancer Center et al, between January 2012 and June 2023 were collected. There were 1 449 males and 629 females, aged (59±11) years. Patients were classified as early recurrence and late recurrence based on the time of post-operative recurrence. Observation indicators: (1) comparison of clinicopathological characteristics between gastric cancer patients with different recurrence types; (2) recurrence and metastasis of tumor; (3) survival of patients after postoperative recurrence of gastric cancer; (4) analysis of influencing factors for early recurrence after gastrectomy for gastric cancer. Comparison of measurement data with normal distribution between groups was conducted using the independent sample t test. Comparison of measurement data with skewed distribution between groups was conducted using the Mann-Whitney U test. Comparison of count data between groups was conducted using the chi-square test. Comparison of ordinal data between groups was conducted using the rank sum test. Multivariate analysis was conducted using the Logistic regression model. Kaplan-Meier method was used to calculate survival rate and plot survival curve, and Log-rank test was used for survival analysis. Results:(1) Comparison of clinicopathological characteristics between gastric cancer patients with different recurrence types. Among the 2 078 patients, 1 452 cases had early recurrence and 626 cases had late recurrence. There were significant differences in preoperative carcinoembryonic antigen, preoperative CA19-9, preoperative CA72-4, preoperative albumin, tumor diameter, neoadjuvant therapy, R 0 resection, combined organ resection, scope of gastric resection, nerve and vessel infiltration, degree of tumor differentiation, pathological N staging, pathological TNM staging between early and late recurrence patients ( P<0.05). (2) Recurrence and metastasis of tumor. Among the 2 078 patients, 200 cases had local recurrence, 1 213 cases had hematogenous metastases, 392 cases had distant lymph node metastases, and 731 cases had peritoneal metastases. Among the 1 452 early recurrence patients, 142 cases had local recurrence, 834 cases had hematogenous metastases, 289 cases had distant lymph node metastases, and 507 cases had peritoneal metastases. Among the 626 late recurrence patients, 58 cases had local recurrence, 379 cases had hematogenous metastases, 103 cases had distant lymph node metastases, and 224 cases had peritoneal metastases. One patient may have multiple forms of recurrence and metastasis. There was no significant difference in the above indica-tors between early and late recurrence patients ( χ2=0.13, 1.74, 3.40, 0.14, P>0.05). (3) Survival of patients after postoperative recurrence of gastric cancer. All 2 078 patients were followed up until death after recurrence, with a follow-up time of 31(range, 9?147)months. The 1-, 2-, 3-, and 5-year overall survival rates after recurrence were 33.5%, 17.2%, 10.1%, and 3.3% in early recurrence patients, versus 44.2%, 21.6%, 12.8%, and 5.8% in late recurrence patients, respectively, showing a significant difference in overall survival after recurrence between the two groups ( hazard ratio=0.84, 95% confidence interval as 0.76?0.92, P<0.05). (4) Analysis of influencing factors for early recurrence after gastrectomy for gastric cancer. Results of multivariate analysis showed that combined organ resection, total gastrectomy, pathological TNM staging as stage Ⅲ were independent risk factors for early recurrence after gastrectomy for gastric cancer ( odds ratio=1.31, 1.32, 1.34, 95% confidence interval as 1.01?1.70, 1.06?1.65, 1.05?1.71, P<0.05) and normal preoperative tumor markers, neoadjuvant therapy, R 0 resection were independent protective factors for early recurrence ( odds ratio=0.61, 0.50, 0.38, 95% confidence interval as 0.49?0.76, 0.35?0.72, 0.25?0.58, P<0.05). Conclusions:Compared with patients with late recurrence after gastric cancer surgery, patients with early recurrence have a poor prognosis, in which liver metastases is more common. Combine organ resection, total gastrectomy, pathological TNM staging as stage Ⅲ are independent risk factors for early recurrence, and normal preoperative tumor markers, neoadjuvant therapy, R 0 resection are independent protective factors for early recurrence after gastrectomy for gastric cancer.

Objective:To investigate the impact of neoadjuvant immunotherapy combined with chemotherapy on the safety and efficacy of radical resection in patients with cT3-4NxM0 gastric cancer.Methods:A retrospective cohort study method was used. The clinicopathological data of 515 patients who underwent radical gastrectomy after neoadjuvant treatment at Second Department of Gastric Surgery,Fudan University Shanghai Cancer Center and Department of Gastric Surgery,Zhangzhou Hospital Affiliated to Fujian Medical University from January 2020 to June 2023 were collected. Among them,379 patients received neoadjuvant chemotherapy alone(chemotherapy group),and 136 patients received neoadjuvant immunotherapy combined with chemotherapy(immunotherapy group). There were 382 males and 133 females,with an age of (58.4±10.9)years(range:26 to 85 years). To reduce the influence of potential confounding factors,a 1∶1 propensity score matching method was adopted,and the clamp value was 0.02. The peri-operative safety,imaging and postoperative pathological tumor regression,and prognosis were compared by independent sample t-test, Mann-Whitney U test, χ 2 test or Fisher exact probability method between the two groups. The Kaplan-Meier method was used to draw survival curves, and the differences between groups were compared by Log-rank test. Results:After matching, there were 101 patients in each of the chemotherapy group and the immunotherapy group. The baseline data of the patients in the two groups were evenly distributed (all P>0.05). According to the RECIST 1.1 criteria, the complete response rate (11.9% (12/101) vs. 4.0% (4/101)), partial response rate(68.3%(69/101) vs. 53.4%(54/101)), stable disease rate (17.8%(18/101) vs. 39.6%(40/101)) and disease progression rate (2.0%(2/101) vs. 3.0%(3/101)) between the immunotherapy group and the chemotherapy group were no statistical defferences ( χ2=14.374, P=0.002), and objective response rate (80.2%(81/101) vs. 57.4%(58/101), χ2=12.203, P<0.01) in the immunotherapy group was higher than that in the chemotherapy group. The results of postoperative pathological examination showed that the immunotherapy group had a higher complete response rate (16.8%(17/101) vs. 6.9% (7/101), χ2=4.728, P=0.030) and major pathological response rate (42.6%(43/101) vs. 23.8% (24/101), χ2=8.062, P=0.005). For the two groups, the operation time (175.0(76.0)minutes vs. 160.0 (30.0)minutes, Z=-0.059, P=0.953), intraoperative blood loss (110.0 (150.0)ml vs. 100.0 (120.0)ml, Z=-0.370, P=0.712), overall incidence of postoperative complications (20.8%(21/101) vs. 18.8%(19/101), χ2=0.125, P=0.724) and incidence of severe complications (5.0%(5/101) vs. 3.0%(3/101), χ2=0.130, P=0.718) were comparable. The median follow-up time of all patients was 46 months(range: 19 to 61 months). The 3-year overall survival rate (63.2% vs. 54.4%, P=0.035) and progression-free survival rate (59.1% vs. 45.6%, P=0.022) of the immunotherapy group were higher than those of the chemotherapy group. Meanwhile, there were no statistically significant differences in the incidence of neoadjuvant-treatment-related adverse events (48.5%(49/101) vs. 40.6% (41/101), χ2=1.283, P=0.411) and the incidence of severe adverse reactions of grade 3 or above (13.9% (14/101) vs. 10.9% (11/101), χ2=0.257, P=0.522) between the two groups. Conclusion:Neoadjuvant immunotherapy combined with chemotherapy can significantly improve the imaging and postoperative pathological tumor response rates and 3-year survival rate of patients with locally advanced gastric cancer,without increasing the incidence of postoperative complications and neoadjuvant treatment-related adverse event.