Humans ; Biopsy, Fine-Needle ; Carcinoma/pathology* ; Esophagogastric Junction/pathology* ; Cytodiagnosis ; DNA Helicases ; Nuclear Proteins ; Transcription Factors

Objective: To investigate the safety and efficacy of laparoscopic surgery in locally advanced gastric cancer patients with neoadjuvant SOX chemotherapy combined with PD-1 inhibitor immunotherapy. Methods: Between November 2020 and April 2021, patients with locally advanced gastric cancer who were admitted to the Union Hospital of Tongji Medical College of Huazhong University of Science and Technology were prospectively enrolled in this study. Inclusion criteria were: (1) patients who signed the informed consent form voluntarily before participating in the study; (2) age ranging from 18 to 75 years; (3) patients staged preoperatively as cT3-4N+M0 by the TNM staging system; (4) Eastern Collaborative Oncology Group score of 0-1; (5) estimated survival of more than 6 months, with the possibility of performing R0 resection for curative purposes; (6) sufficient organ and bone marrow function within 7 days before enrollment; and (7) complete gastric D2 radical surgery. Exclusion criteria were: (1) history of anti-PD-1 or PD-L1 antibody therapy and chemotherapy; (2) treatment with corticosteroids or other immunosuppre- ssants within 14 days before enrollment; (3) active period of autoimmune disease or interstitial pneumonia; (4) history of other malignant tumors; (5) surgery performed within 28 days before enrollment; and (6) allergy to the drug ingredients of the study. Follow-up was conducted by outpatient and telephone methods. During preoperative SOX chemotherapy combined with PD-1 inhibitor immunotherapy, follow-up was conducted every 3 weeks to understand the occurrence of adverse reactions of the patients; follow-up was conducted once after 1 month of surgical treatment to understand the adverse reactions and survival of patients. Observation indicators were: (1) condition of enrolled patients; (2) reassessment after preoperative therapy and operation received (3) postoperative conditions and pathological results. Evaluation criteria were: (1) tumor staged according to the 8th edition of the American Joint Committee on Cancer (AJCC) TNM staging system; (2) tumor regression grading (TRG) of pathological results were evaluated with reference to AJCC standards; (3) treatment-related adverse reactions were evaluated according to version 5.0 of the Common Terminology Criteria for Adverse Events; (4) tumor response was evaluated by CT before and after treatment with RECIST V1.1 criteria; and (5) Clavien-Dindo complication grading system was used for postoperative complications assessment. Results: A total of 30 eligible patients were included. There were 25 males and 5 females with a median age of 60.5 (35-74) years. The primary tumor was located in the gastroesophageal junction in 12 cases, in the upper stomach in 8, in the middle stomach in 7, and in the lower stomach in 3. The preoperative clinical stage of 30 cases was III. Twenty-one patients experienced adverse reactions during neoadjuvant chemotherapy combined with immunotherapy, including four cases of CTCAE grade 3-4 adverse reactions resulting in bone marrow suppression and thoracic aortic thrombosis. All cases of adverse reactions were alleviated or disappeared after active symptomatic treatment. Among the 30 patients who underwent surgery, the time from chemotherapy combined with immunotherapy to surgery was 28 (23-49) days. All 30 patients underwent laparoscopic radical gastrectomy, of which 20 patients underwent laparoscopic-assisted radical gastric cancer resection; 10 patients underwent total gastrectomy for gastric cancer, combined with splenectomy in 1 case and cholecystectomy in 1 case. The surgery time was (239.9±67.0) min, intraoperative blood loss was 84 (10-400) ml, and the length of the incision was 7 (3-12) cm. The degree of adenocarcinoma was poorly differentiated in 18 cases, moderately differentiated in 12 cases, nerve invasion in 11 cases, and vascular invasion in 6 cases. The number lymph nodes that underwent dissection was 30 (17-58). The first of gas passage, the first postoperative defecation time, the postoperative liquid diet time, and the postoperative hospitalization time of 30 patients was 3 (2-6) d, 3 (2-13) d, 5 (3-12) d, and 10 (7-27) d, respectively. Postoperative complications occurred in 23 of 30 patients, including 7 cases of complications of Clavien-Dindo grade IIIa or above. Six patients improved after treatment and were discharged from hospital, while 1 patient died 27 days after surgery due to granulocyte deficiency, anemia, bilateral lung infection, and respiratory distress syndrome. The remaining 29 patients had no surgery-related morbidity or mortality within 30 days of discharge. Postoperative pathological examination showed TRG grades 0, 1, 2, and 3 in 8, 9, 4, and 9 cases, respectively, and the number of postoperative pathological TNM stages 0, I, II, and III was 8, 7, 8, and 7 cases, respectively. The pCR rate was 25.0% (8/32). Conclusion: Laparoscopic surgery after neoadjuvant SOX chemotherapy combined with PD-1 inhibitor immunotherapy for locally advanced gastric cancer is safe and feasible, with satisfactory short-term efficacy. Early detection and timely treatment of related complications are important.
Male ; Female ; Humans ; Middle Aged ; Aged ; Adolescent ; Young Adult ; Adult ; Stomach Neoplasms/pathology* ; Neoadjuvant Therapy ; Immune Checkpoint Inhibitors ; Gastrectomy/methods* ; Esophagogastric Junction/pathology* ; Laparoscopy ; Immunotherapy ; Postoperative Complications ; Retrospective Studies ; Treatment Outcome

Objective: To evaluate the effects on short-term clinical outcomes and long-term quality of life of laparoscopic-assisted radical proximal gastrectomy with esophageal gastric tube anastomosis versus total gastrectomy with Roux-en-Y anastomosis for adenocarcinoma of the esophagogastric junction. Methods: This was a propensity score matching, retrospective, cohort study. Clinicopathological data of 184 patients with adenocarcinoma of the esophagogastric junction admitted to two medical centers in China from January 2016 to January 2021 were collected (147 in the First Affiliated Hospital of Xiamen University and 37 in the Affiliated Hospital of Qinghai University). All patients had undergone laparoscopic-assisted radical gastrectomy. They were divided into two groups based on the extent of tumor resection and technique used for digestive tract reconstruction. A proximal gastrectomy with reconstruction by esophageal gastric tube anastomosis group comprised 82 patients and a total gastrectomy with reconstruction by Roux-en-Y anastomosis group comprised 102 patients. These groups differed significantly in the following baseline characteristics: age, preoperative hemoglobin, preoperative albumin, tumor length, tumor differentiation, and tumor TNM stage (all P<0.05). To eliminate potential bias caused by unequal distribution between the two groups, 1∶1 matching was performed by the nearest neighbor matching method. The 13 matched variables comprised sex, age, height, body mass, body mass index, preoperative glucose, preoperative hemoglobin, preoperative total protein, preoperative albumin, neoadjuvant radiotherapy, tumor length, degree of differentiation, and pathological TNM stage. Postoperative complications, postoperative nutritional status, incidence of reflux esophagitis 1 year after surgery, and quality of life were compared between the two groups. Results: After propensity score matching, 60 patients each were enrolled in the proximal gastrectomy with esophageal gastric tube anastomosis and total gastrectomy with Roux-en-Y anastomosis groups. The baseline characteristics were comparable between these groups (all P>0.05). There were no significant differences between the two groups in operative time, intraoperative bleeding, time to semifluid diet, postoperative hospital days, tumor length, and total hospital costs (P>0.05). Patients in the proximal gastrectomy with esophageal gastric tube anastomosis group had earlier postoperative gastric tube and abdominal drainage tube removal time than those in the total gastrectomy with Roux-en-Y anastomosis group (t=-2.183, P=0.023 and t=-4.073, P<0.001, respectively). In contrast, significantly fewer lymph nodes were cleared and significantly fewer lymph nodes were positive in the proximal gastrectomy with esophageal gastric tube anastomosis group than in the total gastrectomy with Roux-en-Y anastomosis group (t=-5.754, P<0.001 and t=-2.575, P=0.031, respectively). The incidence of early postoperative complications was 43.3% (26/60) in the total gastrectomy with Roux-en-Y anastomosis group; this is not significantly higher than the 26.7% (16/60) in the proximal gastrectomy with esophageal gastric tube anastomosis group (χ²=3.663，P=0.056). The incidences of pulmonary infection (31.7%, 19/60) and pleural effusion (30.0%, 18/60) were significantly higher in the total gastrectomy with Roux-en-Y anastomosis group than in the proximal gastrectomy with esophageal gastric tube anastomosis group (13.3%, 8/60 and 8.3%, 5/60, respectively); these differences are significant (χ²=8.711, P=0.003 and χ²=11.368, P=0.001, respectively). All early complications were successfully treated before discharge. The incidence of long-term postoperative complications was 20.0% (12/60) in the total gastrectomy with Roux-en-Y anastomosis group and 35.0% (21/60) in the proximal gastrectomy with esophageal gastric tube anastomosis group; this difference is not significant (χ²=3.386，P=0.066). The incidence of reflux esophagitis was 23.3% (14/60) in the proximal gastrectomy with esophageal gastric tube anastomosis group; this is significantly higher than the 1.7% (1/60) in the total gastrectomy with Roux-en-Y anastomosis group (χ²=12.876, P<0.001). Body mass index had decreased significantly in both groups 1 year after surgery compared with preoperatively; however, the difference between the two groups was not significant (P>0.05). The differences in hemoglobin and albumin concentrations between 1 year postoperatively and preoperatively were not significant (both P>0.05). Quality of life was assessed using the Visick grade. Visick grade I dominated in both groups. The percentage of patients with Visick II and III in the total gastrectomy with Roux-en-Y anastomosis group was 11.7% (7/60), which is significantly lower than the 33.3% (20/60) in the proximal gastrectomy with esophageal gastric tube anastomosis group (χ²=8.076, P=0.004). No patients in either group had a grade IV quality of life. Conclusions: Both proximal gastrectomy with esophageal gastric tube anastomosis and total gastrectomy with Roux-en-Y anastomosis laparoscopic-assisted radical surgery for adenocarcinoma of the esophagogastric junction are safe and feasible. However, both procedures have their own advantages and disadvantages in terms of postoperative complications. The incidence of reflux esophagitis is higher after proximal gastrectomy with esophageal gastric tube anastomosis, whereas the long-term quality of life is lower than that of patients after total gastrectomy with Roux-en-Y anastomosis.
Humans ; Anastomosis, Roux-en-Y ; Retrospective Studies ; Cohort Studies ; Esophagitis, Peptic ; Quality of Life ; Propensity Score ; Gastrectomy/methods* ; Esophagogastric Junction/surgery* ; Anastomosis, Surgical/methods* ; Adenocarcinoma/pathology* ; Stomach Neoplasms/pathology* ; Postoperative Complications ; Treatment Outcome

Objective: We aimed to explore the feasibility of a single-port thoracoscopy- assisted five-step laparoscopic procedure via transabdominal diaphragmatic(TD) approach(abbreviated as five-step maneuver) for No.111 lymphadenectomy in patients with Siewert type II esophageal gastric junction adenocarcinoma (AEG). Methods: This was a descriptive case series study. The inclusion criteria were as follows: (1) age 18-80 years; (2) diagnosis of Siewert type II AEG; (3) clinical tumor stage cT2-4aNanyM0; (4) meeting indications of the transthoracic single-port assisted laparoscopic five-step procedure incorporating lower mediastinal lymph node dissection via a TD approach; (5) Eastern Cooperative Oncology Group performance status (ECOG PS) 0-1; and (6) American Society of Anesthesiologists classification I, II, or III. The exclusion criteria included previous esophageal or gastric surgery, other cancers within the previous 5 years, pregnancy or lactation, and serious medical conditions. We retrospectively collected and analyzed the clinical data of 17 patients (age [mean ± SD], [63.6±11.9] years; and 12 men) who met the inclusion criteria in the Guangdong Provincial Hospital of Chinese Medicine from January 2022 to September 2022. No.111 lymphadenectomy was performed using five-step maneuver as follows: superior to the diaphragm, starting caudad to the pericardium, along the direction of the cardio-phrenic angle and ending at the upper part of the cardio-phrenic angle, right to the right pleura and left to the fibrous pericardium , completely exposing the cardio-phrenic angle. The primary outcome includes the numbers of harvested and of positive No.111 lymph nodes. Results: Seventeen patients (3 proximal gastrectomy and 14 total gastrectomy) had undergone the five-step maneuver including lower mediastinal lymphadenectomy without conversion to laparotomy or thoracotomy and all had achieved R0 resection with no perioperative deaths. The total operative time was (268.2±32.9) minutes, and the lower mediastinal lymph node dissection time was (34.0±6.0) minutes. The median estimated blood loss was 50 (20-350) ml. A median of 7 (2-17) mediastinal lymph nodes and 2(0-6) No. 111 lymph nodes were harvested. No. 111 lymph node metastasis was identified in 1 patient. The time to first flatus occurred 3 (2-4) days postoperatively and thoracic drainage was used for 7 (4-15) days. The median postoperative hospital stay was 9 (6-16) days. One patient had a chylous fistula that resolved with conservative treatment. No serious complications occurred in any patient. Conclusion: The single-port thoracoscopy-assisted five-step laparoscopic procedure via a TD approach can facilitate No. 111 lymphadenectomy with few complications.
Male ; Female ; Humans ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged ; Aged, 80 and over ; Diaphragm/surgery* ; Retrospective Studies ; Feasibility Studies ; Esophagogastric Junction/surgery* ; Lymph Node Excision/methods* ; Stomach Neoplasms/pathology* ; Laparoscopy/methods* ; Gastrectomy/methods* ; Esophageal Neoplasms/pathology* ; Adenocarcinoma/pathology* ; Thoracoscopy

The electrophysiological activity of the gastrointestinal tract and the mechanical anti-reflux structure of the gastroesophageal junction are the basis of the anti-reflux function of the stomach. Proximal gastrectomy destroys the mechanical structure and normal electrophysiological channels of the anti-reflux. Therefore, the residual gastric function is disordered. Moreover, gastroesophageal reflux is one of the most serious complications. The emergence of various types of anti-reflux surgery through the mechanism of reconstructing mechanical anti-reflux barrier and establishing buffer zone, and the preservation of, the pacing area and vagus nerve of the stomach, the continuity of the jejunal bowel, the original gastroenteric electrophysiological activity of the gastrointestinal tract, and the physiological function of the pyloric sphincter, are all important measures for gastric conservative operations. There are many types of reconstructive approaches after proximal gastrectomy. The design based on the anti-reflux mechanism and the functional reconstruction of mechanical barrier, and the protection of gastrointestinal electrophysiological activities are important considerations for the selected of reconstructive approaches after proximal gastrectomy. In clinical practice, we should consider the principle of individualization and the safety of radical resection of tumor to select a rational reconstructive approaches after proximal gastrectomy.
Humans ; Stomach Neoplasms/surgery* ; Gastrectomy ; Gastroesophageal Reflux ; Esophagogastric Junction/surgery* ; Pylorus/pathology*

Objective: To investigate the outcome of patients with esophagogastric junction cancer undergoing thoracoscopic laparoscopy-assisted Ivor-Lewis resection. Methods: Eighty-four patients who were diagnosed with esophagogastric junction cancer and underwent Ivor-Lewis resection assisted by thoracoscopic laparoscopy at the National Cancer Center from October 2019 to April 2022 were collected. The neoadjuvant treatment mode, surgical safety and clinicopathological characteristics were analyzed. Results: Siewert type Ⅱ (92.8%) and adenocarcinoma (95.2%) were predominant in the cases. A total of 2 774 lymph nodes were dissected in 84 patients. The average number was 33 per case, and the median was 31. Lymph node metastasis was found in 45 patients, and the lymph node metastasis rate was 53.6% (45/84). The total number of lymph node metastasis was 294, and the degree of lymph node metastasis was 10.6%(294/2 774). Among them, abdominal lymph nodes (100%, 45/45) were more likely to metastasize than thoracic lymph nodes (13.3%, 6/45). Sixty-eight patients received neoadjuvant therapy before surgery, and nine patients achieved pathological complete remission (pCR) (13.2%, 9/68). Eighty-three patients had negative surgical margins and underwent R0 resection (98.8%, 83/84). One patient, the intraoperative frozen pathology suggested resection margin was negative, while vascular tumor thrombus was seen on the postoperative pathological margin, R1 resection was performed (1.2%, 1/84). The average operation time of the 84 patients was 234.5 (199.3, 275.0) minutes, and the intraoperative blood loss was 90 (80, 100) ml. One case of intraoperative blood transfusion, one case of postoperative transfer to ICU ward, two cases of postoperative anastomotic leakage, one case of pleural effusion requiring catheter drainage, one case of small intestinal hernia with 12mm poke hole, no postoperative intestinal obstruction, chyle leakage and other complications were observed. The number of deaths within 30 days after surgery was 0. Number of lymph nodes dissection, operation duration, and intraoperative blood loss were not related to whether neoadjuvant therapy was performed (P>0.05). Preoperative neoadjuvant chemotherapy combined with radiotherapy or immunotherapy was not related to whether postoperative pathology achieved pCR (P>0.05). Conclusion: Laparoscopic-assisted Ivor-Lewis surgery for esophagogastric junction cancer has a low incidence of intraoperative and postoperative complications, high safety, wide range of lymph node dissection, and sufficient margin length, which is worthy of clinical promotion.
Humans ; Blood Loss, Surgical ; Lymphatic Metastasis/pathology* ; Esophagectomy ; Esophageal Neoplasms/pathology* ; Retrospective Studies ; Lymph Node Excision ; Postoperative Complications/epidemiology* ; Laparoscopy ; Esophagogastric Junction/pathology*

Objective: To compare the prognostic influence and postoperative pathology of different comprehensive treatment models for adenocarcinoma of esophagogastric junction. Methods: Between January 2012 and December 2017, a total of 219 patients with adenocarcinoma of esophagogastric junction underwent surgery in Gastrointestinal Cancer Center, Peking University Cancer Hospital & Institute and were enrolled in this study. The clinicopathological data of these patients were collected. The patients were categorized into 3 groups according to different treatment models: surgery-first group, neoadjuvant chemotherapy (NAC) group and neoadjuvant chemoradiotherapy (nCRT) group. A trimatch propensity score analysis was applied to control potential confounders among the three groups by using R language software. A total of 7 covariates including gender, age, comorbidity, body mass index, clinical T stage, clinical N stage and Siewert type were included, and the caliper value was taken as 0.2. After matching, a total of 87 patients were included for analysis with 27 patients for each group. There were 82 males and 5 females, with a median age of 63 years (range: 38 to 76 years). The effect of preoperative treatment on postoperative tumor pathology among the three different comprehensive treatment models was explored by χ² test, ANOVA or Wilcoxon rank sum test. Mann-Whitney U test or χ² test were used to undergo pairwise comparisons. Kaplan-Meier method and Log-rank test were used to analyze the overall survival and progression-free survival. Results: The proportion of vascular embolism in the surgery-first group was 72.4% (21/29), which was significantly higher than NAC group (37.9% (11/29), χ²=6.971, P=0.008) and nCRT group (6.9% (2/29), χ²=26.696, P<0.01). The proportions of pathological T3-4 stage in nCRT group and NAC group were 55.2% (16/29) and 62.1% (18/29), respectively, which were significantly lower than the surgery-first group (93.1% (27/29), χ²=10.881, P=0.001; χ²=8.031, P=0.005). Compared with the NAC group (55.2% (16/29), χ²=6.740, P=0.009) and nCRT group (31.0% (9/29), χ²=18.196, P<0.01), the proportion of lymph node positivity 86.2% (25/29) were significantly higher in the surgery-first group. The 5-year overall survival rates were 62.1%, 68.6% and 41.4% for the surgery-first group, NAC group and nCRT group, respectively (χ²=4.976, P=0.083). The 5-year progression-free survival rates were 61.7%, 65.1% and 41.1% for the surgery-first group, NAC group and nCRT group, respectively. The differences in overall survival (χ²=4.976, P=0.083) and progression-free survival (χ²=4.332, P=0.115) among the three groups were nonsignificant. Conclusions: Postoperative pathology is significantly different among the three groups. Neoadjuvant chemotherapy and neoadjuvant chemoradiotherapy could decrease the proportions of vascular embolism, pathological T3-4 stage and lymph node positivity to achieve local tumor control. The prognosis of overall survival and progression-free survival are not significantly different among the three groups.
Adenocarcinoma/pathology* ; Adult ; Aged ; Cohort Studies ; Esophagogastric Junction/pathology* ; Female ; Humans ; Male ; Middle Aged ; Neoadjuvant Therapy ; Propensity Score

Objective: To examine the long term outcome of splenic hilar lymphadenectomy (SHL) for locally advanced Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction (AEG) with a tumor diameter ≥4 cm. Methods: A total of 489 locally advanced Siewert type Ⅱ and Ⅲ AEG patients with a tumor diameter ≥4 cm who underwent radical resection from January 2010 to April 2016 were included. There were 383 males and 106 females. There were 225 patients aged≥65 years and 264 patients aged <65 years. SHL was conducted in 270 patients(SHL group). Wilcoxon rank-sum test or χ² test were conducted for inter-group comparison. Cox proportional hazard regression was used to analyze the long term outcome of SHL and the prognosis factors of overall survival. Kaplan-Meier curve was drawn finally. The results of survival analysis were verified by Log-rank test. Results: Followed-up to April 2021,the median follow-up time was 78.0 months (range: 74.0 to 85.0 months), the follow-up rate was 95.5%(467/489). The splenic hilar lymphnode metastasis rate of the SHL group was 12.6% (34/270). Younger patients (<65 years old), less complications, higher proportion of patients received adjuvant chemotherapy were demonstrated in the SHL group (χ²: 5.644 to 6.744, all P<0.05). Multivariate analysis showed that SHL was the independent prognosis factor of overall survival for patients with Siewert type Ⅱ and Ⅲ AEG and a tumor diameter≥4 cm (HR=0.68, 95%CI: 0.52 to 0.88, P=0.004) along with preoperative CA19-9, pathological T stage, pathological N stage, adjuvant chemotherapy and postoperative complication. Further subgroup analysis demonstrated that the SHL group had better 5-year overall survival than non-SHL group (62.4% vs. 39.2%, χ²=17.983, P=0.006) in Siewert type Ⅲ AEG rather than in Siewert type Ⅱ AEG(57.3% vs. 53.7%, χ²=3.031, P=0.805). Conclusion: In experienced center, splenic hilar lymphadenectomy can improve the prognosis of Siewert type Ⅲ AEG with a tumor diameter ≥4 cm.
Adenocarcinoma/surgery* ; Aged ; Esophageal Neoplasms ; Esophagogastric Junction/surgery* ; Female ; Humans ; Lymph Node Excision/methods* ; Lymphatic Metastasis/pathology* ; Male ; Retrospective Studies ; Stomach Neoplasms/surgery* ; Survival Analysis

The incidence of Siewert type II adenocarcinoma of the esophagogastric junction (AEG) is increasing year by year. Due to its special anatomical location and biological behavior, the treatment of AEG is still controversial in terms of lymph node dissection, the esophageal resection margin, range of gastrectomy, and the choice of reconstruction modality for postoperative gastrointestinal tract. The advent of the minimally invasive era has brought the treatment of Siewert type II AEG to a stage of gradual improvement and standardization. Experts of China are also actively exploring the value of minimally invasive surgery in the treatment of AEG through multicenter trials (CLASS-10, etc.). It is believed that based on the active development of many clinical studies, basic experimental studies and large prospective clinical studies, the strengthening of communication and cooperation among various disciplines and the innovative application of new technologies can bring greater survival benefits to patients.
Adenocarcinoma/pathology* ; Esophageal Neoplasms/surgery* ; Esophagogastric Junction/surgery* ; Gastrectomy ; Humans ; Lymph Node Excision ; Minimally Invasive Surgical Procedures ; Prospective Studies ; Retrospective Studies ; Stomach Neoplasms/pathology*

A greater controversy remains in clinical diagnosis and treatment of Siewert type II adenocarcinoma of esophagogastric junction (AEG), compared with Siewert type I and III AEG. In 2018, the first edition of Chinese Expert Consensus on the Surgical Treatment for Adenocarcinoma of Esophagogastric Junction was published in the Chinese Journal of Gastrointestinal Surgery. In the past few years, the advance in minimally invasive thoracoscopic surgery has been proven to reduce thoracic trauma in Siewert type II AEG. Meanwhile, distal thoracic esophagectomy can achieve more complete resection, and upper abdomen-right thoracic approach can ensure the mediastinal lymph node dissection and improve long-term survival. The concept and practice of endoscopic surgery and the comprehensive treatment also give new supplements to the treatment regimen of Siewert type II AEG. More clinical researches should be conducted to address the surgical residual safety and lymph node dissection issues.
Adenocarcinoma/pathology* ; Esophageal Neoplasms/surgery* ; Esophagogastric Junction/surgery* ; Gastrectomy ; Humans ; Lymph Node Excision ; Retrospective Studies ; Stomach Neoplasms/surgery* ; Thoracic Surgery