Objective:To investigate the risk factors of pathological complete response(pCR)after neoadjuvant therapy for locally advanced gastric cancer(LAGC)and assess the value of gastric tumor markers for predicting pCR in LAGC patients.Methods:We retrospectively ana-lyzed the clinical and pathological characteristics of 213 patients who underwent radical gastrectomy and gastric tumor marker analysis after neoadjuvant therapy at The Chinse PLA General Hospital First Medical Center,between January 2020 and April 2024(20 and 193 cases in the pCR and non-pCR groups,respectively).The interrelationships among pCR,tumor markers,and clinicopathological features were compared,and independent risk factors for pCR were analyzed.A nomogram was constructed to predict the pCR.Results:Among 213 patients,20(9.4% )achieved pCR.Univariate analysis showed that age(P=0.067),tumor bed diameter(P<0.001),gastrin-17 levels(P=0.005),CA72-4 levels(P=0.073),pepsinogen ratio(P=0.024),and neoadjuvant immunotherapy(P=0.022)were strongly associated with pCR in LAGC pa-tients.Multivariate analysis showed that neoadjuvant immunotherapy,CA72-4 levels<2.5 U/mL,gastrin-17 levels<1.48 pmol/L,and tumor bed diameter<2.85 cm were independent predictive factors for pCR in LAGC patients(P<0.05).These indicators were incorporated into a nomogram prediction model;an receiver operating characteristic curve(ROC)was plotted with an AUC(95% CI)of 0.863(0.785-0.942).The calibration and decision curves suggested that the nomogram was well calibrated and had a good net benefit.Conclusions:Gastric tumor markers can effectively predict pCR after neoadjuvant therapy in LAGC patients.Our nomogram showed a good predictive ability for pCR.Thus,our findings can serve as a useful reference for clinical decision making for LAGC patients.

Objective:To investigate the treatment and prognosis of patients of G3 non-functional pancreatic neuroendocrine tumors (pNETs) with proliferation index of Ki-67 <55%.Methods:The retrospective and descriptive study was conducted. The clinicopathological data of 15 G3 non-functional pNETs patients with proliferation index of Ki-67<55% who were admitted to Zhongshan Hospital of Fudan University from April 2014 to April 2020 were collected. There were 11 males and 4 females, aged (58±10)years. All patients underwent radical resection of the primary lesion. Obser-vation indicators: (1) treatment; (2) postoperative pathological characteristics; (3) follow-up. Measure-ment data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M( Q1, Q3) or M(range). Count data were described as absolute numbers. The Pearson correlation analysis was used to verify the correlation between variables. Kaplan-Meier method was used to draw survival curve and calculate survival rate. Log-Rank test was used for survival analysis. Results:(1) Treatment. All 15 G3 nonfunctional pNETs patients underwent radical resection of the primary lesion of pancreas, including 5 cases receiving pancreati-coduodenectomy, 10 cases receiving distal pancreatectomy with splenectomy. There were 5 patients with simultaneous liver oligometastasis who underwent combined segmental (lobectomy) hepatectomy. All 15 patients had negative tumor margin, and the operation time and volume of intraoperative blood loss of 15 patients was 120(90,210)minutes and 200(50,300)mL, respectively. None of patient had complications ≥Ⅲ grade of the Clavien-Dindo classification during the postoperative 30 days. Of the 15 patients, there were 5 cases receiving comprehensive treatment based on CAPTEM chemo-therapy (temozolomide combined with capecitabine), 2 cases receiving local interventional therapy, 2 cases receiving CAPTEM chemotherapy, 1 case receiving local interventional therapy combined with molecular targeted therapy, 1 case receiving local interventional therapy combined with long acting somatostatin therapy, 1 cases receiving long acting somatostatin therapy combined with molecular targeted therapy, and 3 cases without postoperative treatment. (2) Postoperative patholo-gical characteristics. The tumor diameter of 15 patients was 3.3(range, 0.5-6.0)cm. There were 2 cases with tumor diameter <2 cm, 13 cases with tumor diameter ≥2 cm. The number of lymph nodes dissected and number of lymph nodes metastatic was 6(4, 10) and 2(1,3) in 15 patients, respectively, including 12 cases with positive lymph node metastasis. Of the 15 patients, there were 5 cases with tumor invasion of adjacent organ, 5 cases with simultaneous liver metastasis, 8 cases with perineural invasion and 8 cases with vascular invasion. There were 3, 7, and 5 patients with stage Ⅱ, stage Ⅲ, and stage Ⅳ of pathological TNM staging, respectively. The proliferation index of Ki-67 and mitotic count was 32%±9% and (11±9)/10 high power field in the primary lesion of 15 patients, respectively, and there was no correlation between proliferation index of Ki-67 and mitotic count ( P>0.05). (3) Follow-up. All 15 patients were followed up after surgery for (55±24)months. The median survival time of 15 patients was 78(range, 43-113)months, with 1-, 3-, 5-year overall survival rate as 100%, 92%, 62%, respectively. During the follow up, 9 of the 15 patients underwent tumor recurrence, with the recurrence time as 20(14, 44)months. There were 8 patients died of tumor recurrence or metastasis. The median survival time was 86(range, 51-120)months in 5 patients receiving comprehensive treatment based on CAPTEM chemotherapy, versus 53(range, 45-60)months in 10 patients receiving other postoperative adjuvant therapy or without postoperative treatment, showing a significant difference between them ( χ2=4.21, P<0.05). Conclusion:The prognosis of patients of G3 nonfunctional pNETs with proliferation index of Ki-67<55% undergoing radical resection combined with postoperative comprehensive treatment based on CAPTEM chemotherapy in better than that of patients receiving other postoperative adjuvant therapy or without posto-perative treatment.

Pancreaticoduodenectomy (PD) is a major operation of abdominal surgery, with high risk, complex operation, more complications and high mortality. Pancreatic fistula is the main cause of death after PD. Due to its complexity and obstinacy, pancreatic fistula has become the top challenge of pancreatic surgery. The authors review the relevant literature and summarize the prevention and management of pancreatic fistula after PD, such as the optimization strategies for pancreatic anastomosis, the use of external stents, prophylactic drains in surgical field, the applica-tion of somatostatin and its analogues, and whole-course nutrition management, based on the precise and comprehensive opinion, in order to provide reference for improving the prevention and treatment of pancreatic fistula after PD.

Pancreatic neuroendocrine neoplasms (pNENs) is one of the gastrointestinal malignancies of significantly heterogeneous, pathologically classified into well differentiated pancreatic neuro-endocrine tumors (pNETs) and poorly differentiated pancreatic neuroendocrine carcinomas. The prognosis and treatment response of pNETs are primely determined by tumor-intrinsic biolo-gical behavior. Accordingly, surgeons need to operate debulking surgery for low-risk patients, as well as implement adjuvant therapies for those at high-risk of relapse and metastasis after curative resection. Notably, as to two distinct subtypes of patients who suffer primary tumor with diameter less than 2 cm and functional pNETs, oncological benefits and functionally symptomatic control should be considered when formulating surgical strategies. In recent years, advances in next-generation sequencing and organoid technologies have provided practical tools for revealing the gene mutations and tumor microenvironment of pNETs. The four signalling pathways, including mTOR signalling, histone modification, altered telomere length and DNA damage repair pathways, are related to the occurrence and development of pNETs and can be used for the personalization precision therapy of pNETs and guiding the development of new drugs. Empirical therapy and clinical trial studies of pNETs are a continuum of contradictions. Therefore, clinicians need to summarize the rules in treatment and develop disciplines in the summary. Based on relevant literatures, the authors explore the hot issues related to pNENs in recent years, in order to provide reference for the diagnosis and treatment of this disease.

Objective:To analyze the reflux parameters of patients with gastroesophageal reflux disease (GERD) in upright position, supine position and at 2 h after meals, and to explore the cut-off value, sensitivity and specificity of the reflux parameters in different positions and at 2 h after meals in GERD diagnosis.Methods:From January 2016 to July 2020, 200 GERD patients (GERD group) and 61 non-GERD patients (control group) who visited Huazhong University of Science and Technology Union Shenzhen Hospital (Former Nanshan District People′s Hospital), were selected. All the patients of the two groups received gastroesophageal reflux disease questionnaire (GERDQ), upper gastrointestinal endoscopy, esophageal high resolution manometry and 24 h esophageal pH combined impedance monitoring. T test, non-parametric test and chi-square test were used to compare the related parameters in upright position, supine position and at 2 h after meals between two groups and within each group. Receiver oparative characteristic (ROC) curves of reflux parameters in upright position, supine position and 2 h after meals were drawn to determine the cut-off value, sensitivity and specificity in GERD diagnosis. Results:The proportion of patients with acid reflux in supine position of the control group was higher than that of the GERD group (41.0%, 25/61 vs. 8.50%, 17/200), and the difference was statistically significant ( χ2=36.53, P<0.01). In the control group, the acid reflux time in upright position, number of acid reflux, acid exposure time (AET), longest reflux time and number of weak acid reflux were more than those of in supine position in the same group (6.00 min(2.00 min, 13.50 min) vs. 0.00 min(0.00 min, 1.50 min), 16.00(8.00, 27.00) vs. 1.00(0.00, 3.00), 0.90%(0.33%, 1.88%) vs. 0.00%(0.00%, 0.30%), 2.00 min(1.00 min, 4.00 min) vs. 0.00 min(0.00 min, 1.00 min), 7.00(3.00, 11.00) vs. 1.00(0.00, 2.00), respectively) and the differences were statistically significant ( Z=5.43, 6.61, 5.06, 3.58 and 6.24, all P<0.01). In the GERD group, the acid reflux time, number of acid reflux, AET, longest reflux time and number of weak acid reflux in upright position were higher than those in supine position (51.00 min, (31.00 min, 86.75 min) vs. 8.00 min(1.00 min, 42.00 min), 60.00(48.00, 83.75) vs.6.00(2.00, 19.50), 7.30%(3.90%, 12.10%) vs. 1.50%(0.20%, 6.50%), 7.00 min(4.00, 12.00 min) vs. 4.00 min(1.00 min, 17.00 min), 1.00(0.00, 3.00) vs. 0.00(0.00, 2.00), 7.00(3.00, 12.00) vs. 0.00(0.00, 1.00), respectively) and the differences were statistically significant ( Z=7.92, 11.22, 6.90, 2.56, 5.11 and 11.76, all P<0.05). The acid reflux time, number of acid reflux, AET, longest reflux time and number of weak acid reflux at 2 h postprandial were 3.00 min(2.00 min, 9.00 min), 10.00(5.00, 18.00), 0.90%(0.40%, 1.98%), 1.00 min(0.00 min, 3.00 min), 4.00(1.50, 8.50)and 28.50 min(15.00 min, 54.75 min), 35.00(24.00, 52.00), 8.30%(4.32%, 15.83%), 6.00 min(3.00 min, 11.00 min), 4.00(2.00, 7.25), in the control and GERD groups, respectively, which were significantly higher than those in supine position in the same group ( Z=4.30, 6.33, 5.50, 3.40, 5.71 and 3.76, 9.21, 5.76, 1.97, 10.46, all P<0.05). Among 200 GERD patients, 125 patients had symptoms recorded during the 24 h esophageal pH combined impedance monitoring, the incidence of reflux symptoms in upright position was higher than that in supine position (89.6%, 112/125 vs. 65.6%, 82/125), and the difference was statistically significant ( χ2=20.71, P<0.01). The results of ROC curve analysis showed that the accuracy of acid reflux time in upright position in GERD prediction was the highest, with AUC value of 0.94 and cut-off value of 24.5 min, and the sensitivity and specificity in GERD diagnosis were 81.50% and 95.08%, respectively. The prediction accuracy of acid reflux times in upright position and AET in upright position for GERD was secondary, AUC value both were 0.93 and the cut-off value of the acid reflux number in upright position was 39.5, and the sensitivity and specificity in GERD diagnosis were 84.00% and 95.08%, respectively. The cut-off value of AET in upright position was 2.75%, the sensitivity and specificity in GERD diagnosis were 85.00% and 93.33%, respectively. The AUC value, cut-off value, sensitivity and specificity of AET at 2 h postprandial were 0.91, 4.60%, and 73.49% and 95.00%, respectively. Conclusions:Both GERD patients and non-GERD patients have more reflux in upright position, especially within 2 h after meals. The diagnostic values of acid reflux time in upright position, number of acid reflux, AET and AET 2 h after meals for GERD is high, and the AUC values are all >0.90, which can be used as a more comprehensive basis for the analysis and diagnosis of GERD.

Objective:To explore the surgical technique and efficacy of pure retroperitoneoscopic extravesical standardized seeable (P.R.E.S.S.) technique for bladder cuff excision (BCE).Methods:Ninety five patients with UTUC from five domestic centers (30 cases from Changzheng Hospital, 21 cases from Peking University First Hospital, 20 cases from Yuhuangding Hospital, 21 cases from Dalian Medical University affiliated No.2 Hospital and 3 cases from General Hospital of Eastern Theater Command)between August 2017 and December 2020 were retrospectively analyzed. There were 57 males and 38 females with a mean age of (67.7±10.0) years and median tumor size of 3.0 cm. All patients underwent pure retroperitoneoscopic radical nephroureterectomy with a single surgical position and four (36 cases) or five (59 cases) trocar layout according to the surgeon’s prefer habit and experience. The demographics of the two groups were the age of [(66.3±11.2)years vs. (68.6±9.1)years], male/female ratio of (25/11 cases vs. 32/27 cases), body mass index of [(25.0± 3.0)kg/m 2 vs. (24.8±3.4)kg/m 2], tumor maximum diameter of [2.8(1.6, 3.5)cm vs. 3.0(2.0, 4.0)cm], left/right side tumor of(19/17 cases vs. 34/25 cases), T 1-2/T 3-4/Tis stage of(25/10/4 cases vs. 49/10/0 cases), and multifocal tumors of(3 cases vs. 2 cases), and the difference was not statistically significant( P>0.05). On the other hand, the differences of hydronephrosis of the operated kidney(13 cases vs. 39 cases, P=0.004), and tumor location (in renal pelvis or calyx or upper/middle/lower ureter being 23/9/4 cases vs. 35/4/20 cases, P=0.005), were statistically significant. The umbilical artery cord was used as anatomical landmark in the process of P. R.E.S.S. bladder cuff excision. The pelvic floor and extraperitoneal space around the ureter were expanded, the bladder wall was opened to form pneumovesicum, and a sufficient bladder cuff resection and exact bladder cuff closure was performed. Perioperative outcomes and follow-up data were analyzed, and the clinical outcomes between the four and five trocars were compared to evaluate the impact of trocar layout on the surgical outcomes. Results:There were 91(95.8%) cases successfully undergoing P. R.E.S.S. BCE technique, with one case converted to open BCE due to bleeding and three cases converted to distal ureter Hem-o-lok clipping because of poor exposure. Median operative time was 180(125, 230)min, and estimated blood loss was 100(50, 100)ml. The overall complication rate was 10.5%(10/95), including 2 cases(2.1%) of intraoperative bleeding, with 1 case treated by transfusion (400 ml), the other case converted to open surgery without transfusion. There were 8 cases of postoperative complications(8.4%), including 7 cases of Clavien-Dindo grade Ⅱ(3 cases of secondary hemorrhage, one case for each of drug allergy, acute renal insufficiency, blood creatinine increased to 490 μmol/L, or lung infection with lymphatic leakage), 1 case of grade Ⅲa(intestinal obstruction treated with insertion of the intestinal obstruction catheter under local anesthesia), and all these patients were discharged smoothly. The difference between the four and five trocars was not statistically significant in the following variables, including the rate of surgical conversion(8.3% vs. 1.7%), estimated intraoperative blood loss(100 ml vs. 60 ml), ratio of intraoperative lymph node dissection (25.0% vs.20.3%), P. R.E.S.S. bladder cuff excision success rate(91.7% vs.98.3%), the incidence of intraoperative and postoperative complications (13.8% vs.8.5%), pT 1-2/pT 3-4/pTis stage(22/11/3 cases vs.37/19/3 cases) and the proportion of recurrence or metastasis(8.3% vs.3.4%)(all P>0.05). However, the differences in the operation time(190 min vs.170 min, P=0.011)and postoperative hospital stay(5 d vs.6 d, P=0.005) were statistically significant. Conclusions:P. R.E.S.S. bladder cuff resection technique is safe and feasible during the procedure of pure retroperitoneoscopic radical nephroureterectomy by a single surgical position and facilitates seeable adequate bladder cuff excision by establishing an enlarged pelvic lateral extraperitoneal space and pneumovesicum. Five-trocar technique is more suitable for patients with lower ureteral tumors but may be associated with a longer postoperative hospital stay compared with the four-trocar technique.

Objective:To investigate the relationship between the E2 and E4 alleles of apolipoprotein E (apoE) gene and myocardial infarction (MI) in type 2 diabetes Mellitus (T2DM) patients, and to explore the relationship between apoE polymorphism and blood lipid metabolism.Methods:This case control study was conducted from August 2016 to March 2020 in China-Japan Friendship Hospital, 3 459 inpatients with T2DM were included including 3 044 patients without MI (T2DM group) and 415 patients with MI (T2DM+MI group). Real time fluorescent quantitative PCR was used to detect apoE polymorphism. Automatic biochemical analyzer was used to detect lipid levels. Logistic regression analyses were performed to determine the association of apoE with risk of MI in patients with T2DM.Results:(1) The frequency of E4 allele in T2DM+MI group (12.29%, 102/830) was significantly higher than in T2DM group (9.13%,556/6 088), while the frequency of E2 allele in T2DM+MI group (7.35%,61/830) was significantly lower than that in T2DM group (8.21%,500/6 088), P=0.012. Logistic regression analyses showed that E4 allele carrier (E3/E4+E4/E4) faced a higher risk for MI in T2DM patients ( OR=1.48, 95% CI 1.14-1.92, P=0.003), while E2 allele carrier(E2/E3+E2/E2)did not face a higher risk of MI in T2DM patients ( OR=0.88, P=0.642). (2) The levels of apoE polymorphism and blood lipid: The levels of TC, LDL-C and apoB increased in the order of E4 allele, wild type and E2 allele ( P<0.05). The levels of HDL-C, apoA1 and apoE decreased in the order of E4 allele, Wild type and E2 allele ( P<0.05). Conclusion:The E4 allele is a risk factor for MI in T2DM patients, and apoE polymorphism can affect blood lipid level in this patent cohort.

Objective: To investigate clinicopathological features and prognostic factors of gastric neuroendocrine tumors (G-NEN). Methods: Clinical and pathological data of patients with G-NEN diagnosed by pathological examination in Chinese PLA General Hospital from January 2000 to June 2018 were retrospectively analyzed in this case-control study. Patients with complicated visceral lesions, other visceral primary tumors, mental disorders and incomplete clinicopathological data were excluded. Finally, 240 hospitalized patients who met the inclusion criteria were enrolled. Physical examination information, tumor characteristics and pathological characteristics of patients were summarized. The Cox regression models were used to analyze the risk factors affecting G-NEN and the survival conditions were described by Kaplan-Meier survival curves and log-rank test. Results: In 240 patients with G-NEN, the mean age was (60.3±10.1) years; 181 were male (75.4%) and 59 females (24.6%); mean tumor diameter was (4.2±2.8) cm; 51 cases (21.2%) were neuroendocrine tumor (NET), 139 cases (57.9%) neuroendocrine carcinoma (NEC), 50 cases (20.8%) mixed neuroendocrine carcinoma (MANEC); 28 cases (11.7%) were G1 low grades, 34 cases (14.2%) G2 medium grades, and 178 cases (74.2%) G3 high grades; tumor infiltration depth T1 to T4 were 44 cases (18.3%), 27 cases (11.2%), 60 cases (25.0%) and 109 cases (45.4%) respectively; 163 cases (67.9%) developed lymphatic metastasis and 46 patients (19.2%) distant metastasis; tumor stage from stage I to stage IV were 55 cases (22.9%), 42 cases (17.5%), 94 cases (39.2%) and 53 cases (22.1%) respectively. Of the 240 G-NEN patients, 223 cases (92.9%) were followed up. The median survival time of the patients was 39.2 (95% CI: 29.1 to 47.5) months. Univariate survival analysis showed that age ≥ 60 years, tumor diameter ≥ 4.2 cm, tumor grade G3, lymphatic metastasis, distant metastasis, and tumor stage III-IV were risk factors for G-NEN patients. Multivariate survival analysis revealed that lymphatic metastasis (HR=1.783, 95%CI: 1.007-3.155, P=0.047) and distant metastasis (HR=2.288, 95% CI: 1.307-4.008, P=0.004) were independent risk factors of the prognosis. Further analysis of the G3 subgroup of G-NEN showed that the 5-year survival rate of NET-G3 was 76.19%, which was significantly higher than that of NEC-G3 and MANEC-G3 (15.60% and 24.73%, P=0.012). Conclusions Most G-NEN patients are in advanced stage at diagnosis. Lymphatic metastasis and distant metastasis indicate poor prognosis. The prognosis of high proliferation NET-G3 patients is better as compared to those of NEC-G3 and MANEC-G3. This classification is worth further attention.

Objective:To compare short-term efficacy of robotic versus 3D laparoscopic-assisted D2 radical distal gastrectomy in gastric cancerpatients and those with different body mass index (BMI).Method:A retrospective cohort study was performed. Inclusion criteria:(1) gastric cancer proved by preoperative pathological results and tumor location was suitable for D2 radical distal gastrectomy; (2) no distal metastases such as in liver, kidney or abdominal cavity, and no direct invasion to the pancreas or colon on preoperative imaging; (3) postoperative pTNM stage ranged from I to III; (4) no conversion to open surgery or change of surgical procedure during operation; (5) complete clinicopathological data. Patients with severe chronic diseases, other malignant tumors, tumor invasion of other organs or distant metastases, benign gastric tumors, gastrointestinal stromal tumors and recurrent gastric cancer were excluded. According to the above criteria, 531 patients who underwent robotic or 3D laparoscopic-assisted distal gastrectomy at the General Surgery Department of Chinese PLA General Hospital from January 2016 to December 2019 were enrolled. Among them, 344 patients underwent 3D laparoscopic-assisted distal gastrectomy (3D-LADG group), including 250 males, 94 females, 66 cases (19.2%) with a BMI ≥ 25 kg/m 2, and 278 cases (80.8%) with a BMI < 25 kg/m 2, and 187 patients underwent robotic-assisted distal gastrectomy (RADG group), including 122 males, 65 females, 69 cases (36.9%) with a BMI≥25 kg/m 2 and 118 cases (63.1%) with a BMI < 25kg/m 2. There were no significant differences in baseline characteristics between the two groups (all P > 0.05). Operative indicators, postoperative recovery, pathological characteristics and complication rate were compared between the two groups. Subgroup analysis stratified BMI was also performed. Results:Compared with RADG group, 3D-LADG group presented more harvested lymph nodes (29.1±12.4 vs. 25.2±9.0, t=4.238, P<0.001), shorter postoperative hospital stay [8.0 (7.0 to 10.0) days vs. 10.0 (9.0 to 11.0) days, Z=-6.205, P<0.001], less operative cost [(3.6×10 4±1.1×10 4) yuan vs. (6.2×10 4±3.5×10 4) yuan, t=-9.727, P<0.001], less cost of hospitalization [8.6×10 4(7.5×10 4 to 10.0×10 4) yuan vs. 12.8×10 4(11.7×10 4 to 14.1×10 4) yuan, Z=-15.997, P<0.001] and longer first flatus time [(3.9±1.0) days vs. (3.4±1.2) days, t=4.271, P<0.001], whose differences were all statistically significant (all P<0.05). While there were no statistically significant differences in operation time, intraoperative blood loss, overall complication rate [10.8%(37/344) vs. 12.8%(24/187), χ 2=0.515, P=0.473] and severe complications rate [2.0%(7/344) vs. 3.2%(6/187), χ 2=0.294, P=0.588] between 3D-LADG group and RADG group (all P>0.05). In BMI<25 kg/m 2 group, propensity score matching (PSM) was used to reduce bias of baseline characteristics. After PSM, 3D-LADG group presented higher proportion of intraoperative blood loss <50 ml [26.7% (31/116) vs. 8.6% (10/116), χ 2=13.065, P<0.001], more harvested lymph nodes [30.3±12.2 vs. 25.3±9.5, t=-3.192, P=0.002] and shorter postoperative hospital stay [9.0 (7.0 to 10.0) days vs. 10.0 (9.0 to 11.0) days, Z=-4.275, P<0.001] compared with RADG group, while other perioperative indicators showed no statistically significant differences between the two groups (all P>0.05). In BMI≥25 kg/m 2 group, 3D-LADG group presented higher proportion of intraoperative blood loss >200 ml [18.2% (12/66) vs. 1.4% (1/69), χ 2=10.853, P=0.001] and shorter postoperative hospital stay [8.0 (6.0 to 10.0) days vs. 9.0 (8.0 to 10.5) days, Z=-3.039, P=0.002] compared with RADG group, while other perioperative indicators also showed no statistically significant differences between the two groups (all P>0.05). Conclusion:It is safe and feasible to perform 3D-LADG and RADG for patients with gastric cancer. The short-term efficacy of both is similar.

Objective:Gastric cancer in adolescents is rare, with only a few cases reported in the literature. The purpose of this study is to investigate the clinicopathological features and prognostic factors of gastric cancer in adolescents aged 10-24 years.Methods:A case-controlled study was performed. The clinicopathological data of gastric cancer patients aged 10-24 years who were treated at the First Medical Center of Chinese PLA General Hospital from February 2000 to February 2017 were retrospectively collected and compared with those patients over 40 years old at the same period, which were randomly selected in a ratio of 1:2. All the patients were followed up until June 2019 and Cox proportional hazard model was used to analyze prognostic factors in the adolescent patients.Results:A total of 63 adolescent gastric cancer patients (0.4% of all 14 794 gastric cancer patients) were enrolled, including 31 males (49.2%) and 32 females (50.8%), with a mean body mass index of (19.5±4.3) kg/m 2. Before diagnosis, Only 35 cases (55.6%) had warning symptoms such as weight loss, ascites, obstruction, hematemesis, black stool, etc.; 5 cases (7.9%) had a family history of gastrointestinal tumor. The median duration of symptoms before diagnosis was 3 months. At diagnosis, 58 cases (92.1%) were poorly differentiated, 57 cases (90.5%) were T3-4 stage, 19 cases (30.2%) were signet ring cell cancer or mucous adenocarcinoma, 57 cases (90.5%) had lymph node metastasis, and 36 cases (57.1%) had distant metastasis. Twenty-nine patients (46.0%) underwent radical surgery, 12 patients underwent palliative surgery, 5 patients underwent exploratory laparotomy, 17 patients were unable to operate due to late stage. Of 56 cases (88.9%) with TNM stage Ⅲ-Ⅳ, 51 patients (81.0%) received chemotherapy. Of the 126 patients over 40 years old, 98 cases (77.8%) were male and 28 cases (22.2%) were female, and the mean body mass index was (23.8±3.2) kg/m 2. There were 60 cases (47.6%) with low differentiation, 90 cases (71.4%) with T3-4, 16 cases (12.7%) with signet ring cell cancer and mucous cell cancer, 79 cases (62.7%) with lymph node metastasis, and 12 cases (9.5%) with distant metastasis. A total of 115 cases (91.3%) underwent radical surgery. Of 74 cases (58.7%) with TNM stage Ⅲ-Ⅳ, 67 cases received (53.2%) chemotherapy. The 63 adolescent gastric cancer patients had lower body mass index, and higher proportion in female, poorly differentiation, signet ring cell cancer and mucous cell cancer, T3-4 stage, lymph node metastasis, distant metastasis, TNM stage Ⅲ-Ⅳ and receiving chemotherapy compared with 126 gastric cancer patients over 40 years old (all P<0.05). Among the 63 adolescent gastric cancer patients, 52 cases (82.5%) were followed up with median follow-up time of 72.1 (36.1, 100.8) months, and the median survival time was 10.4 months (95% CI: 6.5-15.1). The 1-year, 3-year and 5-year survival rates were 44.2%, 25.0% and 18.0%, respectively. Univariate analysis showed that the depth of tumor invasion (HR=7.15, 95% CI:1.71-29.89, P=0.007), lymph node metastasis (HR=6.00, 95% CI:1.42 - 25.42, P=0.015), distant metastasis (HR=7.25, 95% CI: 3.25 - 16.18, P<0.001), TNM stage (HR=5.49, 95% CI: 1.67-18.12, P=0.005) and tumor resection (HR=0.18, 95% CI: 0.09-0.37, P<0.001) were the risk factors affecting the prognosis of adolescent gastric cancer patients. Multivariate survival analysis showed that distant metastasis was an independent factor for gastric cancer survival in adolescents (HR=3.67, 95% CI: 1.32-10.19, P=0.012). Conclusions:Gastric cancer in adolescents is insidious and progresses rapidly. Most of them are in the advanced stage at diagnosis and have low rate of radical excision.