[Efficacy of laparoscopic proximal gastrectomy with double-tract reconstruction versus laparoscopic total gastrectomy with Roux-en-Y reconstruction for early upper gastric cancer].

Objective: To compare clinical efficacy between laparoscopic radical proximal gastrectomy with double-tract reconstruction (LPG-DTR) and laparoscopic radical total gastrectomy with Roux-en-Y reconstruction (LTG-RY) in patients with early upper gastric cancer, and to provide a reference for the selection of surgical methods in early upper gastric cancer. Methods: A retrospective cohort study method was carried out. Clinical data of 80 patients with early upper gastric cancer who underwent LPG-DTR or LTG-RY by the same surgical team at the Department of General Surgery, the First Affiliated Hospital of Xi'an Jiaotong University from January 2018 to January 2021 were retrospectively analyzed. Patients were divided into the DTR group (32 cases) and R-Y group (48 cases) according to surgical procedures and digestive tract reconstruction methods. Surgical and pathological characteristics, postoperative complications (short-term complications within 30 days after surgery and long-term complications after postoperative 30 days), survival time and nutritinal status were compared between the two groups. For nutritional status, reduction rate was used to represent the changes in total protein, albumin, total cholesterol, body mass, hemoglobin and vitamin B12 levels at postoperative 1-year and 2-year. Non-normally distributed continuous data were presented as median (interquartile range), and the Mann-Whitney U test was used for comparison between groups. The χ(2) test or Fisher's exact test was used for comparison of data between groups. The Mann-Whitney U test was used to compare the ranked data between groups. The survival rate was calculated by Kaplan-Meier method categorical, and compared by using the log-rank test. Results: There were no statistically significant differences in baseline data betweeen the two groups, except that patients in the R-Y group were oldere and had larger tumor. Patients of both groups successfully completed the operation without conversion to laparotomy, combined organ resection, or perioperative death. There were no significant differences in the distance from proximal resection margin to superior margin of tumor, postoperative hospital stay, time to flatus and food-taking, hospitalization cost, short- and long-term complications between the two groups (all P>0.05). Compared with the R-Y group, the DTR group had shorter distal margins [(3.2±0.5) cm vs. (11.7±2.0) cm, t=-23.033, P<0.001], longer surgery time [232.5 (63.7) minutes vs. 185.0 (63.0) minutes, Z=-3.238, P=0.001], longer anastomosis time [62.5 (17.5) minutes vs. 40.0 (10.0) minutes, Z=-6.321, P<0.001], less intraoperative blood loss [(138.1±51.6) ml vs. (184.3±62.1) ml, t=-3.477, P=0.001], with significant differences (all P<0.05). The median follow-up of the whole group was 18 months, and the 2-year cancer-specific survival rate was 97.5%, with 100% in the DTR group and 95.8% in the R-Y group (P=0.373). Compared with R-Y group at postoperative 1 year, the reduction rate of weight, hemoglobin and vitamin B12 were lower in DTR group with significant differences (all P<0.05); at postoperative 2-year, the reduction rate of vitamin B12 was still lower with significant differences (P<0.001), but the reduction rates of total protein, albumin, total cholesterol, body weight and hemoglobin were similar between the two groups (all P>0.05). Conclusions: LPG-DTR is safe and feasible in the treatment of early upper gastric cancer. The short-term postoperative nutritional status and long-term vitamin B12 levels of patients undergoing LPG-DTR are superior to those undergoing LTG-RY.

[A nomogram for predicting lymph node metastasis in early gastric cancer].

Objective: To explore the independent risk factors of lymph node metastasis (LNM) in early gastric cancer, and to use nomogram to construct a prediction model for above LNM. Methods: A retrospective cohort study was conducted. Inclusion criteria: (1) primary early gastric cancer as stage pT1 confirmed by postoperative pathology; (2) complete clinicopathological data. Exclusion criteria: (1) patients with advanced gastric cancer, stump gastric cancer or history of gastrectomy; (2) early gastric cancer patients confirmed by pathology after neoadjuvant chemotherapy; (3) other types of gastric tumors, such as lymphoma, neuroendocrine tumor, stromal tumor, etc.; (4) primary tumors of other organs with gastric metastasis. According to the above criteria, 1633 patients with early gastric cancer who underwent radical gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital First Medical Center from December 2005 to December 2020 were enrolled as training set, meanwhile 239 patients with early gastric cancer who underwent gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital Fourth Medical Center from December 2015 to December 2020 were enrolled as external validation set. Risk factors of LNM in early gastric cancer were identified by using univariate and multivariate logistic regression analyses. A nomogram prediction model was established with significant factors screened by multivariate analysis. Area under the receiver operating characteristic curve (AUC) was used for assessing the predictive value of the model. Calibration curve was drawn for external validation. Results: Among 1633 patients in training set, the mean number of retrieved lymph nodes was 20 (13-28), and 209 patients (12.8%) had lymph node metastasis. Univariate analysis showed that gender, resection range, tumor location, tumor morphology, lymph node clearance, vascular invasion, lymphatic cancer thrombus, tumor length, tumor differentiation, microscopic presence of signet ring cells and depth of tumor invasion were associated with LNM (all P<0.05). Multivariate analysis revealed that females, tumor morphology as ulcer type, vascular invasion, lymphatic cancer thrombus, tumor length≥3 cm, deeper invasion of mucosa, and poor differentiation were independent risk factors for LNM in early gastric cancers (all P<0.05). Receiver operating characteristic curve indicated that AUC of training set was 0.818 (95%CI: 0.790-0.847) and AUC of external validation set was 0.765 (95%CI: 0.688-0.843). The calibration curve showed that the LNM probability predicted by nomogram was consistent with the actual situation (C-index: 0.818 in training set and 0.765 in external validation set). Conclusions: Females, tumor morphology as ulcer type, vascular invasion, lymphatic cancer thrombus, tumor length≥3 cm, deeper invasion of mucosa and poor differentiation are independent risk factors for LNM of early gastric cancer. The establishment of a nomogram prediction model for LNM in early gastric cancer has great diagnostic value and can provide reference for treatment selection.

Efficacy of laparoscopic proximal gastrectomy with double-tract reconstruction versus laparoscopic total gastrectomy with Roux-en-Y reconstruction for early upper gastric cancer / 中华胃肠外科杂志

Objective: To compare clinical efficacy between laparoscopic radical proximal gastrectomy with double-tract reconstruction (LPG-DTR) and laparoscopic radical total gastrectomy with Roux-en-Y reconstruction (LTG-RY) in patients with early upper gastric cancer, and to provide a reference for the selection of surgical methods in early upper gastric cancer. Methods: A retrospective cohort study method was carried out. Clinical data of 80 patients with early upper gastric cancer who underwent LPG-DTR or LTG-RY by the same surgical team at the Department of General Surgery, the First Affiliated Hospital of Xi'an Jiaotong University from January 2018 to January 2021 were retrospectively analyzed. Patients were divided into the DTR group (32 cases) and R-Y group (48 cases) according to surgical procedures and digestive tract reconstruction methods. Surgical and pathological characteristics, postoperative complications (short-term complications within 30 days after surgery and long-term complications after postoperative 30 days), survival time and nutritinal status were compared between the two groups. For nutritional status, reduction rate was used to represent the changes in total protein, albumin, total cholesterol, body mass, hemoglobin and vitamin B12 levels at postoperative 1-year and 2-year. Non-normally distributed continuous data were presented as median (interquartile range), and the Mann-Whitney U test was used for comparison between groups. The χ(2) test or Fisher's exact test was used for comparison of data between groups. The Mann-Whitney U test was used to compare the ranked data between groups. The survival rate was calculated by Kaplan-Meier method categorical, and compared by using the log-rank test. Results: There were no statistically significant differences in baseline data betweeen the two groups, except that patients in the R-Y group were oldere and had larger tumor. Patients of both groups successfully completed the operation without conversion to laparotomy, combined organ resection, or perioperative death. There were no significant differences in the distance from proximal resection margin to superior margin of tumor, postoperative hospital stay, time to flatus and food-taking, hospitalization cost, short- and long-term complications between the two groups (all P>0.05). Compared with the R-Y group, the DTR group had shorter distal margins [(3.2±0.5) cm vs. (11.7±2.0) cm, t=-23.033, P<0.001], longer surgery time [232.5 (63.7) minutes vs. 185.0 (63.0) minutes, Z=-3.238, P=0.001], longer anastomosis time [62.5 (17.5) minutes vs. 40.0 (10.0) minutes, Z=-6.321, P<0.001], less intraoperative blood loss [(138.1±51.6) ml vs. (184.3±62.1) ml, t=-3.477, P=0.001], with significant differences (all P<0.05). The median follow-up of the whole group was 18 months, and the 2-year cancer-specific survival rate was 97.5%, with 100% in the DTR group and 95.8% in the R-Y group (P=0.373). Compared with R-Y group at postoperative 1 year, the reduction rate of weight, hemoglobin and vitamin B12 were lower in DTR group with significant differences (all P<0.05); at postoperative 2-year, the reduction rate of vitamin B12 was still lower with significant differences (P<0.001), but the reduction rates of total protein, albumin, total cholesterol, body weight and hemoglobin were similar between the two groups (all P>0.05). Conclusions: LPG-DTR is safe and feasible in the treatment of early upper gastric cancer. The short-term postoperative nutritional status and long-term vitamin B12 levels of patients undergoing LPG-DTR are superior to those undergoing LTG-RY.

A nomogram for predicting lymph node metastasis in early gastric cancer / 中华胃肠外科杂志

Objective: To explore the independent risk factors of lymph node metastasis (LNM) in early gastric cancer, and to use nomogram to construct a prediction model for above LNM. Methods: A retrospective cohort study was conducted. Inclusion criteria: (1) primary early gastric cancer as stage pT1 confirmed by postoperative pathology; (2) complete clinicopathological data. Exclusion criteria: (1) patients with advanced gastric cancer, stump gastric cancer or history of gastrectomy; (2) early gastric cancer patients confirmed by pathology after neoadjuvant chemotherapy; (3) other types of gastric tumors, such as lymphoma, neuroendocrine tumor, stromal tumor, etc.; (4) primary tumors of other organs with gastric metastasis. According to the above criteria, 1633 patients with early gastric cancer who underwent radical gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital First Medical Center from December 2005 to December 2020 were enrolled as training set, meanwhile 239 patients with early gastric cancer who underwent gastrectomy at the Department of General Surgery of the Chinese PLA General Hospital Fourth Medical Center from December 2015 to December 2020 were enrolled as external validation set. Risk factors of LNM in early gastric cancer were identified by using univariate and multivariate logistic regression analyses. A nomogram prediction model was established with significant factors screened by multivariate analysis. Area under the receiver operating characteristic curve (AUC) was used for assessing the predictive value of the model. Calibration curve was drawn for external validation. Results: Among 1633 patients in training set, the mean number of retrieved lymph nodes was 20 (13-28), and 209 patients (12.8%) had lymph node metastasis. Univariate analysis showed that gender, resection range, tumor location, tumor morphology, lymph node clearance, vascular invasion, lymphatic cancer thrombus, tumor length, tumor differentiation, microscopic presence of signet ring cells and depth of tumor invasion were associated with LNM (all P<0.05). Multivariate analysis revealed that females, tumor morphology as ulcer type, vascular invasion, lymphatic cancer thrombus, tumor length≥3 cm, deeper invasion of mucosa, and poor differentiation were independent risk factors for LNM in early gastric cancers (all P<0.05). Receiver operating characteristic curve indicated that AUC of training set was 0.818 (95%CI: 0.790-0.847) and AUC of external validation set was 0.765 (95%CI: 0.688-0.843). The calibration curve showed that the LNM probability predicted by nomogram was consistent with the actual situation (C-index: 0.818 in training set and 0.765 in external validation set). Conclusions: Females, tumor morphology as ulcer type, vascular invasion, lymphatic cancer thrombus, tumor length≥3 cm, deeper invasion of mucosa and poor differentiation are independent risk factors for LNM of early gastric cancer. The establishment of a nomogram prediction model for LNM in early gastric cancer has great diagnostic value and can provide reference for treatment selection.

[Interpretation of key points of Chinese expert consensus on function-preserving gastrectomy for gastric cancer (2021)].

Gastric cancer is one of the most common malignant tumors in China, and with the popularity of gastroscopy in recent years, the proportion of early gastric cancer is increasing gradually. Through standardized endoscopic and/or surgical treatment, patients with early gastric cancer usually have a favorable prognosis, which will inevitably lead to higher demands for postoperative quality of life. Based on this situation, function-preserving gastrectomy (FPG) has become a focus in the treatment of early gastric cancer for the purpose of improving the quality of life. The "Chinese expert consensus on function-preserving gastrectomy for early gastric cancer (2021)" will guide surgeons to perform standardized FPG, and ensure the maximum quality of life for the patients.

[Choice of function-preserving gastrectomy].

As the diagnosis rate of early gastric cancer is increasing annually, the current hot spot in the treatment of early gastric cancer is how to better preserve the anatomical structure and physiological function of the stomach and improve the quality of life of patients after surgery under the premise of tumor eradication. Therefore, function-preserving gastrectomy has been the trend of surgical treatment for early gastric cancer. It is not just a modified gastrectomy, but a better combination of improved surgical techniques and the concept of function-preserving treatment, rather than being limited to traditional surgical treatments. Currently, the routine function-preserving gastrectomy mainly includes pylorus-preserving gastrectomy, proximal gastrectomy and partial gastrectomy combined with endoscopy. In addition, with the deeper understanding of metastasis pattern of gastric cancer and the development and popularization of minimally invasive techniques, laparoscopic and endoscopic cooperative surgery is gradually gaining attention. The application of laparoscopic and endoscopic hybrid surgery combined with sentinel lymph node navigation is anticipated in the treatment of early gastric cancer.

[A novel classification and strategy choice of digestive tract reconstruction procedures after function-preserving gastrectomy for early gastric caner].

Function-preserving gastrectomy (FPG) can be regarded as a concrete embodiment of precise treatment for early gastric cancer. Digestive tract reconstruction plays an important role in FPG. The aims of reconstruction mainly include the preservation of normal digestive tract and digestive function, the reconstruction of pivotal anatomical structure, and the consequent improvement of postoperative quality of life. We establish a new classification of digestive tract reconstruction based on the different role of digestive tract reconstructions in FPG for early gastric cancer, meanwhile we briefly summarize current progress and elucidate surgical indications. We hope that it can provide theoretical reference for surgeons to choose the appropriate procedure of digestive tract reconstruction after FPG.

[Comparison of long-term outcomes between endoscopic submucosal dissection and surgical resection for early gastric cancer with undifferentiated histology].

Objective: Endoscopic submucosal dissection (ESD) of undifferentiated early gastric cancer (UD-EGC) remains controversial due to high positive rate of horizontal and vertical resection margins and the risk of lymph node metastasis. The purpose of this study was to compare long-term outcomes of patients with UD-EGC undergoing ESD versus surgery. Methods: This study was a retrospective cohort study. Inclusion criteria: (1) patients with early gastric cancer undergoing ESD or surgical resection; (2) histological types included poorly differentiated adenocarcinoma, poorly differentiated adenocarcima with signet ring cell carcinoma, and signet ring cell carcinoma; (3) no lymph node metastasis or distant metastasis was confirmed by preoperative CT and endoscopic ultrasonography. Exclusion criteria: (1) previous surgical treatment for gastric cancer; (2) synchronous tumors; (3) death with unknown cause; (4) additional surgical treatment was performed within 1 month after ESD. According to the above criteria, clinical data of patients with UD-EGC who received ESD or surgery treatment in Cancer Hospital of Chinese Academy of Medical Sciences from January 2009 to December 2016 were collected. After further comparing the clinical outcomes between the two groups by 1:1 propensity score matching, 61 patients in the ESD group and 61 patients in the surgery group were finally included in this study. The disease-free and overall survivals were analyzed by Kaplan-Meier method. Results: All patients in the two groups completed operations successfully. In the ESD group, the median operation time was 46.3 (26.5, 102.3) minutes, 61 cases (100%) were en-bloc resection, and 57 cases (93.4%) were complete resection. Positive margin was found in 4 (6.6%) patients, of whom 2 were positive in horizontal margin and 2 were positive both in horizontal and vertical margins. In the surgery group, only 1 case had positive horizontal margin and no positive vertical margin was observed. There was no significant difference in the positive rate of margin between the two groups (P>0.05). Median follow-up time was 59.8 (3.0, 131.5) months. The follow-up rate of ESD group and surgery group was 82.0% (50/61) and 95.1% (58/61), respectively. The 5-year disease-free survival rate in ESD group and surgery group was 98.2% and 96.7%, respectively (P=0.641), and the 5-year overall survival rate was 98.2% and 96.6%, respectively (P=0.680). In the ESD group, 1 patient (1.6%) had lymph node recurrence, without local recurrence or distant metastasis. In the surgery group, 1 case (1.6%) had anastomotic recurrence and 1 (1.6%) had distant metastasis. Conclusion: ESD has a sinilar long-term efficacy to surgery in the treatment of UD-EGC.

[Pylorus-preserving gastrectomy and segmental gastrectomy: discrimination of concepts and surgical procedures].

Both pylorus-preserving gastrectomy (PPG) and segmental gastrectomy (SG) achieve the preservation of gastric cardia and pylorus through the circumferential resection of stomach, while concepts and surgical procedures of these two operations are obviously different. In this sense, transectional gastrectomy includes both PPG and SG. PPG is one of the standard surgical procedure for early gastric cancer (EGC). The extent of lymph node dissection (No.1, 3, 4sb, 4d, 6, 7, 8a, 9) and the retention of infrapyloric vessels, hepatic and pyloric branch of vagal nerve has formed a consensus. Meanwhile, SG is regarded as an investigational treatment according to the Japanese gastric cancer treatment guidelines. It is still controversial and may generate an ethical risk in the clinical practice. This article distinguishes the difference in the concepts and surgical procedures between PPG and SG, assisting a comprehensive evaluation in further research.

Pylorus-preserving gastrectomy and segmental gastrectomy: discrimination of concepts and surgical procedures / 中华胃肠外科杂志

Both pylorus-preserving gastrectomy (PPG) and segmental gastrectomy (SG) achieve the preservation of gastric cardia and pylorus through the circumferential resection of stomach, while concepts and surgical procedures of these two operations are obviously different. In this sense, transectional gastrectomy includes both PPG and SG. PPG is one of the standard surgical procedure for early gastric cancer (EGC). The extent of lymph node dissection (No.1, 3, 4sb, 4d, 6, 7, 8a, 9) and the retention of infrapyloric vessels, hepatic and pyloric branch of vagal nerve has formed a consensus. Meanwhile, SG is regarded as an investigational treatment according to the Japanese gastric cancer treatment guidelines. It is still controversial and may generate an ethical risk in the clinical practice. This article distinguishes the difference in the concepts and surgical procedures between PPG and SG, assisting a comprehensive evaluation in further research.

Comparison of long-term outcomes between endoscopic submucosal dissection and surgical resection for early gastric cancer with undifferentiated histology / 中华胃肠外科杂志

Objective: Endoscopic submucosal dissection (ESD) of undifferentiated early gastric cancer (UD-EGC) remains controversial due to high positive rate of horizontal and vertical resection margins and the risk of lymph node metastasis. The purpose of this study was to compare long-term outcomes of patients with UD-EGC undergoing ESD versus surgery. Methods: This study was a retrospective cohort study. Inclusion criteria: (1) patients with early gastric cancer undergoing ESD or surgical resection; (2) histological types included poorly differentiated adenocarcinoma, poorly differentiated adenocarcima with signet ring cell carcinoma, and signet ring cell carcinoma; (3) no lymph node metastasis or distant metastasis was confirmed by preoperative CT and endoscopic ultrasonography. Exclusion criteria: (1) previous surgical treatment for gastric cancer; (2) synchronous tumors; (3) death with unknown cause; (4) additional surgical treatment was performed within 1 month after ESD. According to the above criteria, clinical data of patients with UD-EGC who received ESD or surgery treatment in Cancer Hospital of Chinese Academy of Medical Sciences from January 2009 to December 2016 were collected. After further comparing the clinical outcomes between the two groups by 1:1 propensity score matching, 61 patients in the ESD group and 61 patients in the surgery group were finally included in this study. The disease-free and overall survivals were analyzed by Kaplan-Meier method. Results: All patients in the two groups completed operations successfully. In the ESD group, the median operation time was 46.3 (26.5, 102.3) minutes, 61 cases (100%) were en-bloc resection, and 57 cases (93.4%) were complete resection. Positive margin was found in 4 (6.6%) patients, of whom 2 were positive in horizontal margin and 2 were positive both in horizontal and vertical margins. In the surgery group, only 1 case had positive horizontal margin and no positive vertical margin was observed. There was no significant difference in the positive rate of margin between the two groups (P>0.05). Median follow-up time was 59.8 (3.0, 131.5) months. The follow-up rate of ESD group and surgery group was 82.0% (50/61) and 95.1% (58/61), respectively. The 5-year disease-free survival rate in ESD group and surgery group was 98.2% and 96.7%, respectively (P=0.641), and the 5-year overall survival rate was 98.2% and 96.6%, respectively (P=0.680). In the ESD group, 1 patient (1.6%) had lymph node recurrence, without local recurrence or distant metastasis. In the surgery group, 1 case (1.6%) had anastomotic recurrence and 1 (1.6%) had distant metastasis. Conclusion: ESD has a sinilar long-term efficacy to surgery in the treatment of UD-EGC.

A novel classification and strategy choice of digestive tract reconstruction procedures after function-preserving gastrectomy for early gastric caner / 中华胃肠外科杂志

Function-preserving gastrectomy (FPG) can be regarded as a concrete embodiment of precise treatment for early gastric cancer. Digestive tract reconstruction plays an important role in FPG. The aims of reconstruction mainly include the preservation of normal digestive tract and digestive function, the reconstruction of pivotal anatomical structure, and the consequent improvement of postoperative quality of life. We establish a new classification of digestive tract reconstruction based on the different role of digestive tract reconstructions in FPG for early gastric cancer, meanwhile we briefly summarize current progress and elucidate surgical indications. We hope that it can provide theoretical reference for surgeons to choose the appropriate procedure of digestive tract reconstruction after FPG.

Choice of function-preserving gastrectomy / 中华胃肠外科杂志

As the diagnosis rate of early gastric cancer is increasing annually, the current hot spot in the treatment of early gastric cancer is how to better preserve the anatomical structure and physiological function of the stomach and improve the quality of life of patients after surgery under the premise of tumor eradication. Therefore, function-preserving gastrectomy has been the trend of surgical treatment for early gastric cancer. It is not just a modified gastrectomy, but a better combination of improved surgical techniques and the concept of function-preserving treatment, rather than being limited to traditional surgical treatments. Currently, the routine function-preserving gastrectomy mainly includes pylorus-preserving gastrectomy, proximal gastrectomy and partial gastrectomy combined with endoscopy. In addition, with the deeper understanding of metastasis pattern of gastric cancer and the development and popularization of minimally invasive techniques, laparoscopic and endoscopic cooperative surgery is gradually gaining attention. The application of laparoscopic and endoscopic hybrid surgery combined with sentinel lymph node navigation is anticipated in the treatment of early gastric cancer.

Interpretation of key points of Chinese expert consensus on function-preserving gastrectomy for gastric cancer (2021) / 中华胃肠外科杂志

Gastric cancer is one of the most common malignant tumors in China, and with the popularity of gastroscopy in recent years, the proportion of early gastric cancer is increasing gradually. Through standardized endoscopic and/or surgical treatment, patients with early gastric cancer usually have a favorable prognosis, which will inevitably lead to higher demands for postoperative quality of life. Based on this situation, function-preserving gastrectomy (FPG) has become a focus in the treatment of early gastric cancer for the purpose of improving the quality of life. The "Chinese expert consensus on function-preserving gastrectomy for early gastric cancer (2021)" will guide surgeons to perform standardized FPG, and ensure the maximum quality of life for the patients.

[Characteristics of lymph node metastasis and evaluating the efficacy of endoscopic submucosal dissection in early gastric cancer].

OBJECTIVE: To investigate the correlation between clinicopathological features and lymph node metastasis, and to evaluate the feasibility and efficacy of endoscopic submucosal dissection (ESD) in early gastric cancer (EGC) by comparing with surgery treatment. METHODS: The clinicopathological data of 320 patients with EGC who were treated in Peking University First Hospital between January 2010 and December 2017 were retrospectively reviewed, in which there were 198 cases of surgical procedure and 122 cases of ESD. Characteristics of lymph node metastasis in EGC were analyzed, and lymph node metastasis of EGC with ESD absolute and expanded indications were summarized. The long-term efficacy of ESD and surgical treatment of EGC were compared to evaluate the rationality of absolute and expanded indications of ESD. RESULTS: Lymph node metastasis was detected in 22 (11.1%) of 198 patients. Univariate analysis showed a positive relationship between tumor size (χ2=5.525, P=0.019), depth of invasion(χ2=8.235, P=0.004), histological type (χ2=6.323, P=0.012), lymphovascular invasion (χ2=12.273, P < 0.001) and lymph node metastasis in EGC. Multivariate analysis revealed that depth of invasion(Wald=7.575, P=0.006) and histological type (Wald=6.317, P=0.012) were independent relative factors of lymph node metastasis in EGC. The lymph node metastasis rates of the patients with absolute and expanded ESD indications were both 0%. The 5-year survival rates of the patients who met ESD absolute indication receiving surgery treatment and ESD were 97.6% and 97.9% respectively, and the difference between the two groups was not statistically significant(χ2=0.014, P=0.907).The 5-year survival rates of the patients who met ESD expanded indication receiving surgery treatment and ESD were 96.5% and 91.7% respectively, the difference between the two groups was not statistically significant(χ2=1.061, P=0.303). CONCLUSION: Lymph node metastasis in EGC is mainly correlated with depth of invasion and histological type. Our data indicate that ESD procedure for EGC is comparable to surgery in terms of long-term efficacy in both absolute and expanded indications. However, some studies of a large sample size are still needed for more confirmation.

[Efficacy and safety of pylorus-preserving gastrectomy for early gastric cancer located in the middle third of the stomach: a meta-analysis].

Objective: It is yet to be clarified whether pylorus-preserving gastrectomy (PPG) for early gastric cancer will bring the risk of radical tumor resection, whether it will increase the incidence of postoperative complications, and how much is the benefit of the quality of life for patients after surgery, these issues are not clear. This meta-analysis aims to evaluate the efficacy and safety of pylorus-preserving gastrectomy (PPG) for early middle gastric cancer. Methods: The Chinese and English literatures about PPG and distal gastrectomy (DG) for early gastric cancer were searched from PubMed, Embase, The Cochrane Library, Web of Science, CNKI net and Wanfang database. Literature inclusion criteria: (1) Prospective or retrospective cohort study of PPG and DG for early middle-third gastric cancer published publicly; (2) Patients with early middle-third gastric cancer; (3) The enrolled literatures include at least one of the following outcome indicators: the efficacy indicators include gallstone, residual gastritis, bile reflux, delayed gastric emptying, dumping syndrome, reflux esophagitis and overall complication; the long-term prognostic indicators include 5-year survival rate and 5-year tumor recurrence. Literature exclusion criteria: (1) Reviews, case reports, conference summaries and other non-control studies; (2) Repeated published studies, incomplete studies and unextractable studies; (3) The depth of tumor invasion exceeding submucosa. The search time ended in July 2020. The basic information and evaluation indicators included in the article were extracted. The retrospective study was evaluated using Newcastle-Ottawa literature quality evaluation scale. The prospective randomized controlled study was evaluated using Jadad modified scale. Meta-analysis was performed using Review Manager 5.3. Publication bias was assessed using funnel map. Publication bias was tested using Egger tools. Results: A total of 717 literatures were retrieved, and 17 literatures were enrolled finally, including 2 randomized controlled trials and 15 retrospective studies. A total of 2427 patients were enrolled, including 948 in PPG group and 1479 in DG group. The meta-analysis of the efficacy indicators showed that there were significant differences in gallstones incidence (OR=0.42, 95% CI: 0.28-0.65, P<0.001), residual gastritis incidence (OR=0.50, 95% CI: 0.32-0.77,P=0.002), bile reflux incidence (OR=0.30, 95% CI: 0.20-0.45, P<0.001), delayed gastric emptying incidence (OR=2.40, 95% CI:1.67-3.45, P<0.001), and postoperative dumping syndrome incidence (OR=0.28, 95% CI: 0.15-0.51, P<0.001), while there were no significant differences in postoperative overall complications (OR=0.97, 95% CI: 0.69-1.35, P=0.840), reflux esophagitis incidence (OR=0.79, 95% CI: 0.39-1.61, P=0.520) between the two groups. The meta-analysis of the long-term prognostic indicators showed that no significant differences of 5-year survival (OR=1.02, 95% CI: 0.61-1.71, P=0.940) or 5-year tumor recurrence (OR=0.77, 95% CI: 0.36-1.68, P=0.520) were observed between the two groups. Conclusion: The incidences of gallstone, residual gastritis, dumping syndrome, bile reflux are lower after PPG in early gastric cancer, while the postoperative overall complications and long-term survival are comparable between PPG and DG, indicating that PPG is quite safe and feasible.

[Influence of different anastomotic methods on gastric function].

Segmental gastrectomy is a common function preserving operation, and its combination with sentinel lymph node navigation technology shows a broad prospect in the treatment of early gastric cancer. Commonly anastomosis methods include the follows: (1) Hand-sewn anastomosis: this method is relatively simple, reduces the use of stapler, and can effectively reduce surgical cost. However, laparotomy or small-incision assisted laparoscopic surgery is required to accomplish anastomosis, so the surgical wound is relatively large. (2) Delta anastomosis: this anastomosis is entirely endoscopic, requiring no small incision with less surgical trauma. However, due to the presence of residual cavities in the small curvature of the side-to-side anastomosis, and the possibility of excessive incision of the posterior wall of the stomach, which may shorten the pyloric sleeve, there is an increased risk of gastric stasis after the operation. (3) Hybrid technique: this anastomosis method is safe and effective. However, it requires total endoscopic gastric anterior wall suture, which represents higher requirements for surgeons. Therefore, surgeons experienced in minimally invasive surgeries are recommended to perform this anastomosis. (4) Puncture technique: this anastomotic method is end-to-end anastomosis with low risk of gastric stasis, and is applicable for entirely endoscopic anastomosis. However, the stapler is not typically used for gastrointestinal surgery, which brings certain limitations to clinical promotion. These anastomoses have their own advantages and disadvantages, and their effects on gastric function are also controversial. In conclusion, the development of segmental gastrectomy is still in its infancy, and prospective multicenter randomized controlled trials are awaited to confirm the safety of oncology and standardize the techniques.

[Segmental gastrectomy with cardia preservation for early gastric cancer].

Segmental gastrectomy with cardia preservation can reduce the symptoms of postoperative gastroesophageal reflux and improve the quality of life, which is potentially advantageous among function-preserving gastrectomy procedures. However, due to the limited extent of excision, this procedure is classified as an investigational treatment in the Japanese Gastric Cancer Treatment Guidelines, without wide acceptance in clinical practice. It is generally believed that the surgical indication of segmental gastrectomy is more selected compared to the pylorus-preserving gastrectomy, and there are also differences between their therapeutic goals. The indications of cardia preservation in segmental gastrectomy mainly depend on the T stage, the distance of the resection margin and the metastasis of lymph nodes. Other points of segmental gastrectomy mainly include the scope of lymphadenectomy, the preservation of blood vessels and vagal nerves, which are still controversial in different researches. High-quality evidences are needed to confirm the safety and long-term efficacy of the segmental gastrectomy.

[Combined laparoscopy-endoscopy local resection for early gastric cancer].

The surgical treatment of early gastric cancer (EGC) is undergoing the development of minimally invasive, precise and individualized treatment. The concept is changing from simple emphasis on radical treatment to giving consideration to both radical treatment and functional preservation. Combined laparoscopy-endoscopy local resection can achieve accurate resection of the lesions of EGC and solve the problem of lymph node dissection which cannot be performed in endoscopic mucosal dissection (ESD). At present, there are several methods of combined laparoscopy-endoscopy local resection for EGC, such as laparoscopy-assisted endoscopic full-thickness resection (EFTR), endoscopy-assisted wedge resection (EAWR), combined laparoscopic and endoscopic approach for neoplasia with a non-exposure technique (CLEAN-NET), and non-exposed endoscopic wall-inversion surgery (NEWS). These methods of local resection have the advantages of minimal invasion, shorter operation time, and less blood loss compared to conventional gastrectomy. Concerning the issue of lymph node dissection in combined laparoscopy-endoscopy surgery, sentinel node navigation can be the solution, although cumbersome intraoperative lymph node tracing, operative failure and false negative still exist. As a developing treatment for EGC, combined laparoscopy-endoscopy local resection will have a good application prospect in the future.

Characteristics of lymph node metastasis and evaluating the efficacy of endoscopic submucosal dissection in early gastric cancer / 北京大学学报(医学版)

OBJECTIVE@#To investigate the correlation between clinicopathological features and lymph node metastasis, and to evaluate the feasibility and efficacy of endoscopic submucosal dissection (ESD) in early gastric cancer (EGC) by comparing with surgery treatment.@*METHODS@#The clinicopathological data of 320 patients with EGC who were treated in Peking University First Hospital between January 2010 and December 2017 were retrospectively reviewed, in which there were 198 cases of surgical procedure and 122 cases of ESD. Characteristics of lymph node metastasis in EGC were analyzed, and lymph node metastasis of EGC with ESD absolute and expanded indications were summarized. The long-term efficacy of ESD and surgical treatment of EGC were compared to evaluate the rationality of absolute and expanded indications of ESD.@*RESULTS@#Lymph node metastasis was detected in 22 (11.1%) of 198 patients. Univariate analysis showed a positive relationship between tumor size (χ2=5.525, P=0.019), depth of invasion(χ2=8.235, P=0.004), histological type (χ2=6.323, P=0.012), lymphovascular invasion (χ2=12.273, P < 0.001) and lymph node metastasis in EGC. Multivariate analysis revealed that depth of invasion(Wald=7.575, P=0.006) and histological type (Wald=6.317, P=0.012) were independent relative factors of lymph node metastasis in EGC. The lymph node metastasis rates of the patients with absolute and expanded ESD indications were both 0%. The 5-year survival rates of the patients who met ESD absolute indication receiving surgery treatment and ESD were 97.6% and 97.9% respectively, and the difference between the two groups was not statistically significant(χ2=0.014, P=0.907).The 5-year survival rates of the patients who met ESD expanded indication receiving surgery treatment and ESD were 96.5% and 91.7% respectively, the difference between the two groups was not statistically significant(χ2=1.061, P=0.303).@*CONCLUSION@#Lymph node metastasis in EGC is mainly correlated with depth of invasion and histological type. Our data indicate that ESD procedure for EGC is comparable to surgery in terms of long-term efficacy in both absolute and expanded indications. However, some studies of a large sample size are still needed for more confirmation.