The treatment of gastric cancer in Japan is formulated according to the classification and the guidelines describe treatment methods.The last revision of Japanese Gastric Cancer Treatment Guidelines adopted the 7th edition of TNM stage classification,which was a major revision since the publication.This revision of the 15th edition of the classification is a combination of the revision of the 8th edition TNM classification and clinical experience.A stage revision and a clinical stage were newly established.In addition,the guidelines for the treatment of gastric cancer have also been revised at the same time,becoming the 5th edition,consistent with the new classification and its stage classification.Clinical trials on nationwide wellcontrolled gastric cancer surgery have come to be carried out in recent years,and these results are the source of evidence for the world.These results are also included in this revised guideline.Expansion surgery such as left thoracotomy and laparotomy for esophageal infiltrating gastric cancer and prophylactic para-aortic lymph node dissection is denied from these clinical trials.In total gastrectomy for advanced gastric cancer that does not invade the greater curvature,splenectomy is unnecesary.Since gastrectomy followed by chemotherapy did not show any survival benefit compared with chemotherapy alone in advanced gastric cancer with a single non-curable factor and without bleeding or stenosis,gastrectomy cannot be justified for treatment of patients with these tumors.Laparoscopic pyloric lateral gastrectomy for early gastric cancer is fairly widespread and it is not an exaggeration to say that it is a standardized treatment.However,totally laparoscopic gastrectomy for advanced gastric cancer is currently awaiting results of randomized controlled trials.

Standardized diagnosis and treatment of malignant tumors is very important for the prognosis of patients. Due to the huge land area and large population, there are regional differences in standardized diagnosis and treatment of malignant tumors in China. Therefore, surgical experts from China and Japan planned, and editorial board of Chinese Journal of Digestive Surgery held the meeting of 4K standard Sino-Japanese gastrointestinal minimally invasive surgery with the purpose to build an academic communication platform for Chinese and Japanese experts of young and middle-aged who engaged in gastrointestinal minimally invasive surgery, to promote the standardization and refinements, and to lead the development of gastrointestinal minimally invasive surgery in China. Since 2018, the author had participated in 5 times of the meeting of 4K standard Sino-Japanese gastrointestinal minimally invasive surgery to interpret the operation technology of laparos-copic gastric cancer surgery and introduce the recognition standard of laparoscopic technology of the Japan Society for Endoscopic Surgery. This would promote the standardization of laparoscopic gastric cancer surgery technology, improve the teaching effect of young and middle aged doctors, and promote the overall deve-lopment of the level of diagnosis and treatment of gastric cancer.

Purpose: Prevention of pancreas-related complications after gastric cancer surgery is critical.Polyglycolic acid (PGA) mesh reduces postoperative pancreatic fistula formation following pancreatic resection. However, the clinical efficacy of PGA mesh in gastric cancer surgery has not been adequately investigated. Materials and Methods: This retrospective study compared the short-term outcomes between two groups: patients who underwent minimally invasive R0 gastrectomy for gastric cancer with the use of a PGA mesh (PGA group) and those without the use of a PGA mesh (non-PGA group) at the Cancer Institute Hospital, Tokyo, between January 2019 and May 2023. Propensity score matching (PSM) was performed to adjust for the possible confounding factors. Results: A total of 834 patients were initially included, of whom 614 (307 in each group) remained after PSM. The amylase levels in the drained abdominal fluid on postoperative days 1 and 3 were similar between the PGA and non-PGA groups. The PGA group had a significantly lower incidence of pancreas-related complications of Clavien-Dindo grade ≥2 than that in the non-PGA group (6.8% vs. 2.9%, P=0.025). In subgroup analyses, the odds ratio for pancreas-related complications appeared to be better in the PGA group than in the non-PGA group in patients with American Society of Anesthesiologists Physical Status Classification score of 2 or 3, those operated via a laparoscopic approach, and those undergoing procedures other than proximal gastrectomy. Conclusions The use of PGA mesh significantly reduced pancreas-related complications after minimally invasive surgery for gastric cancer and might thus benefit patients at risk of such complications.

Purpose: Prevention of pancreas-related complications after gastric cancer surgery is critical.Polyglycolic acid (PGA) mesh reduces postoperative pancreatic fistula formation following pancreatic resection. However, the clinical efficacy of PGA mesh in gastric cancer surgery has not been adequately investigated. Materials and Methods: This retrospective study compared the short-term outcomes between two groups: patients who underwent minimally invasive R0 gastrectomy for gastric cancer with the use of a PGA mesh (PGA group) and those without the use of a PGA mesh (non-PGA group) at the Cancer Institute Hospital, Tokyo, between January 2019 and May 2023. Propensity score matching (PSM) was performed to adjust for the possible confounding factors. Results: A total of 834 patients were initially included, of whom 614 (307 in each group) remained after PSM. The amylase levels in the drained abdominal fluid on postoperative days 1 and 3 were similar between the PGA and non-PGA groups. The PGA group had a significantly lower incidence of pancreas-related complications of Clavien-Dindo grade ≥2 than that in the non-PGA group (6.8% vs. 2.9%, P=0.025). In subgroup analyses, the odds ratio for pancreas-related complications appeared to be better in the PGA group than in the non-PGA group in patients with American Society of Anesthesiologists Physical Status Classification score of 2 or 3, those operated via a laparoscopic approach, and those undergoing procedures other than proximal gastrectomy. Conclusions The use of PGA mesh significantly reduced pancreas-related complications after minimally invasive surgery for gastric cancer and might thus benefit patients at risk of such complications.

Purpose: Prevention of pancreas-related complications after gastric cancer surgery is critical.Polyglycolic acid (PGA) mesh reduces postoperative pancreatic fistula formation following pancreatic resection. However, the clinical efficacy of PGA mesh in gastric cancer surgery has not been adequately investigated. Materials and Methods: This retrospective study compared the short-term outcomes between two groups: patients who underwent minimally invasive R0 gastrectomy for gastric cancer with the use of a PGA mesh (PGA group) and those without the use of a PGA mesh (non-PGA group) at the Cancer Institute Hospital, Tokyo, between January 2019 and May 2023. Propensity score matching (PSM) was performed to adjust for the possible confounding factors. Results: A total of 834 patients were initially included, of whom 614 (307 in each group) remained after PSM. The amylase levels in the drained abdominal fluid on postoperative days 1 and 3 were similar between the PGA and non-PGA groups. The PGA group had a significantly lower incidence of pancreas-related complications of Clavien-Dindo grade ≥2 than that in the non-PGA group (6.8% vs. 2.9%, P=0.025). In subgroup analyses, the odds ratio for pancreas-related complications appeared to be better in the PGA group than in the non-PGA group in patients with American Society of Anesthesiologists Physical Status Classification score of 2 or 3, those operated via a laparoscopic approach, and those undergoing procedures other than proximal gastrectomy. Conclusions The use of PGA mesh significantly reduced pancreas-related complications after minimally invasive surgery for gastric cancer and might thus benefit patients at risk of such complications.

Purpose: Prevention of pancreas-related complications after gastric cancer surgery is critical.Polyglycolic acid (PGA) mesh reduces postoperative pancreatic fistula formation following pancreatic resection. However, the clinical efficacy of PGA mesh in gastric cancer surgery has not been adequately investigated. Materials and Methods: This retrospective study compared the short-term outcomes between two groups: patients who underwent minimally invasive R0 gastrectomy for gastric cancer with the use of a PGA mesh (PGA group) and those without the use of a PGA mesh (non-PGA group) at the Cancer Institute Hospital, Tokyo, between January 2019 and May 2023. Propensity score matching (PSM) was performed to adjust for the possible confounding factors. Results: A total of 834 patients were initially included, of whom 614 (307 in each group) remained after PSM. The amylase levels in the drained abdominal fluid on postoperative days 1 and 3 were similar between the PGA and non-PGA groups. The PGA group had a significantly lower incidence of pancreas-related complications of Clavien-Dindo grade ≥2 than that in the non-PGA group (6.8% vs. 2.9%, P=0.025). In subgroup analyses, the odds ratio for pancreas-related complications appeared to be better in the PGA group than in the non-PGA group in patients with American Society of Anesthesiologists Physical Status Classification score of 2 or 3, those operated via a laparoscopic approach, and those undergoing procedures other than proximal gastrectomy. Conclusions The use of PGA mesh significantly reduced pancreas-related complications after minimally invasive surgery for gastric cancer and might thus benefit patients at risk of such complications.

PURPOSE: Postoperative pancreatic fistula is a serious and fatal complication of gastrectomy for gastric cancer. Blunt trauma to the parenchyma of the pancreas can result from an assistant's forceps compressing and retracting the pancreas, which in turn may result in pancreatic juice leakage. However, no published studies have focused on blunt trauma to the pancreas during laparoscopic surgery. Our aim was to investigate the relationship between compression of the pancreas and pancreatic juice leakage in a swine model. MATERIALS AND METHODS: Three female pigs were used in this study. The pancreas was gently compressed dorsally for 15 minutes laparoscopically with gauze grasped with forceps. Pancreatic juice leakage was visualized by fluorescence imaging after topical administration of chymotrypsin-activatable fluorophore in real time. Amylase concentrations in ascites collected at specified times was measured. In addition, pancreatic tissue was fixed with formalin, and the histology of the compressed sites was evaluated. RESULTS: Fluorescence imaging enabled visualization of pancreatic juice leaking into ascites around the pancreas. Median concentrations of pancreatic amylase in ascites increased from 46 U/L preoperatively to 12,509 U/L 4 hours after compression. Histological examination of tissues obtained 4 hours after compression revealed necrotic pancreatic acinar cells extending from the surface to deep within the pancreas and infiltration of inflammatory cells. CONCLUSIONS: Pancreatic compression by the assistant's forceps can contribute to pancreatic juice leakage. These findings will help to improve the procedure for lymph node dissection around the pancreas during laparoscopic gastrectomy.
Acinar Cells ; Administration, Topical ; Amylases ; Ascites ; Female ; Formaldehyde ; Gastrectomy* ; Hand Strength ; Humans ; Laparoscopy ; Lymph Node Excision* ; Lymph Nodes* ; Optical Imaging ; Pancreas ; Pancreatic Fistula ; Pancreatic Juice ; Stomach Neoplasms ; Surgical Instruments ; Swine ; Wounds, Nonpenetrating

A 55-year-old man visited our hospital for a detailed examination of a gastric submucosal tumor that was first detected 10 years prior. The tumor continued to grow and had developed a depressed area in its center. A histopathological examination of biopsy specimens revealed gastric adenocarcinoma of the fundic gland type (GA-FG). It was diagnosed as T2 based on the invasion depth as determined by white-light endoscopy and endoscopic ultrasonography. A total gastrectomy with lymphadenectomy was performed and a GA-FG in the mucosa and submucosa was confirmed histopathologically. However, there was a gradual transition to an infiltrative tubular adenocarcinoma with poorly differentiated components in the muscular and subserosal layers. Metastasis was identified in a dissected lymph node (LN). This is the first report of a GA-FG progressing to an aggressive cancer with LN metastasis. These findings modify our understanding of the pathophysiology of GA-FG.
Adenocarcinoma* ; Biopsy ; Endoscopy ; Endosonography ; Gastrectomy ; Gastric Mucosa ; Humans ; Lymph Node Excision ; Lymph Nodes* ; Middle Aged ; Mucous Membrane ; Neoplasm Metastasis*

Purpose: Although dumping symptoms are thought to involve postprandial glycemic changes, postprandial glycemic variability without dumping symptoms remains poorly understood due to the lack of a method that allows the easy and continuous measurement of blood glucose levels. Materials and Methods: Patients having undergone distal gastrectomy with Billroth-I (DGBI) or Roux-en-Y reconstruction (DG-RY), total gastrectomy with RY (TG-RY) and pylorus preserving gastrectomy (PPG) for gastric cancer 3 months to 3 years prior, diagnosed as pathological stage I or II, were prospectively enrolled from March 2018 to January 2020. The interstitial tissue glycemic levels were measured every 15 min, up to 14 days by continuous glucose monitoring. Moreover, using a diary recording the diet and symptoms, asymptomatic glucose profiles without sugar supplementation within 3 h postprandially were compared among the four procedures. Results: A total of 40 patients were enrolled, 10 patients for each of the four procedures. There were 47 glucose profiles with DG-BI, 46 profiles with DG-RY, 38 profiles with TGRY, and 46 profiles with PPG. PPG showed the slowest increase with a subsequent gradual decrease in glucose fluctuations, without hyperglycemia or hypoglycemia, among the four procedures. In contrast, TG-RY and DG-RY showed spike-like glycemic variability, sharp rises during meals, and rapid drops. The glucose profiles of DG-BI were milder than those of RY. Conclusions The asymptomatic glycemic changes after meals differ among the types of surgical procedures for gastric cancer. Given the mild glycemic fluctuations in PPG and the glucose spikes in TG-RY and DG-RY, pylorus preservation and physiological reconstruction without changes in food pathways may optimize postprandial glucose profiles after gastrectomy.

Purpose: The incidence of early gastric cancer is increasing in older patients alongside life expectancy. For early gastric cancer of the upper third of the stomach, laparoscopic functionpreserving gastrectomy (LFPG), including laparoscopic proximal gastrectomy (LPG) and laparoscopic subtotal gastrectomy (LSTG), is expected to be an alternative to laparoscopic total gastrectomy (LTG). However, whether LFPG has advantages over LTG in older patients remains unknown. Materials and Methods: We retrospectively analyzed data of consecutive patients aged ≥75 years who underwent LTG, LPG, or LSTG for cT1N0M0 gastric cancer between 2005 and 2019. Surgical and nutritional outcomes, including blood parameters, percentage body weight (%BW) and percentage skeletal muscle index (%SMI) were compared between LTG and LPG or LSTG. Survival outcomes were also compared between LTG and LFPG groups. Results: A total of 111 patients who underwent LTG (n=39), LPG (n=48), and LSTG (n=24) were enrolled in this study. To match the surgical indications, LTG was further categorized into “LTG for LPG” (LTG-P) and “LTG for LSTG” (LTG-S). No significant differences were identified in the incidence of postoperative complications among the procedures. Postoperative nutritional parameters, %BW and %SMI were better after LPG and LSTG than after LTG-P and LTG-S, respectively. The survival outcomes of LFPG were better than those of LTG. Conclusions LFPG is safe for older patients and has advantages over LTG in terms of postoperative nutritional parameters, body weight, skeletal muscle-sparing, and survival.Therefore, LFPG for upper early gastric cancer should be considered in older patients.