Function-preserving Gastrectomy Research Articles

Impact of malnutrition and nutritional support after gastrectomy in patients with gastric cancer.

Malnutrition, characterized by altered body composition and impaired function, is particularly prevalent among gastric cancer patients, affecting up to 60% of them. Malnutrition in these patients can manifest both before and after surgery, due to factors such as gastric outlet obstruction, cancer cachexia, and anatomical changes. Notably, total gastrectomy (TG) presents the most significant nutritional challenges. However, function-preserving gastrectomy, such as pylorus-preserving gastrectomy (PPG) and proximal gastrectomy (PG), have shown promise in improving nutritional outcomes. Effective nutritional risk screening and assessment are vital for identifying patients at risk. Nutritional support not only improves nutritional parameters but also reduces complications, enhances quality of life (QoL) and survival rates. Those unable to maintain more than 50% of the recommended intake for over 7 days are recommended for nutritional support. Common methods of nutritional support include oral nutrition supplements (ONS), enteral nutrition (EN), or parenteral nutrition (PN) depending on the patient's status. Effect of perioperative nutritional support remains controversial. Preoperative interventions including ONS and PN have shown mixed results, with selective benefits in patients with sarcopenia or hypoalbuminaemia, while impact of EN in gastric outlet obstruction patients have been positive. In contrast postoperative support appears to be consistent. Tube feeding after TG has shown improvements, and ONS have been effective in reducing weight loss and improving nutritional biomarkers. PN was also associated with benefits such as weight maintenance and QoL. This review explores the mechanisms, assessment, and clinical impact of malnutrition, emphasizing the importance of nutritional support in gastric cancer patients undergoing gastrectomy.

Pylorus-preserving gastrectomy for early gastric cancer.

Pylorus-preserving gastrectomy (PPG) has been widely accepted as a function-preserving gastrectomy for middle-third early gastric cancer (EGC) with a distal tumor border at least 4 cm proximal to the pylorus. The procedure essentially preserves the function of the pyloric sphincter, which requires to preserve the upper third of the stomach and a pyloric cuff at least 2.5 cm. The suprapyloric and infrapyloric vessels are usually preserved, as are the hepatic and pyloric branches of the vagus nerve. Compared with distal gastrectomy, PPG has significant advantages in preventing dumping syndrome, body weight loss and bile reflux gastritis. The postoperative complications after PPG have reached an acceptable level. PPG can be considered a safe, effective, and superior choice in EGC, and is expected to be extensively performed in the future.

Risk factors for remnant gastric cancer after distal gastrectomy for gastric cancer: a retrospective database review.

The number of patients with remnant gastric cancer (RGC) following gastrectomy for gastric cancer (GC) is increasing due to the increasing number of patients undergoing function-preserving gastrectomy and improved outcomes for patients with GC. A few studies involving a small number of cases reported male sex, old age, differentiated type, tumor depth and synchronous multiple GC were associated with RGC development. However, the risk factors for RGC development had not been fully understood. This study aimed to examine the clinicopathological features, followed up patients with GC after they underwent distal gastrectomy (DG), and evaluated the potential risk factors for RGC development. A retrospective database review of 438 patients who underwent DG for GC at a single institution, from 2006 to 2017, was conducted. We investigated the relationship of clinicopathological features, operative findings, and postoperative course with RGC development was estimated using Cox proportional hazard analysis. The cumulative incidences of RGC were calculated using the Kaplan-Meier method. We retrospectively analyzed 405 cases. The median patient age was 69 years, and the patient cohort consisted of 263 men and 142 women. The Billroth-I reconstruction method was used in 204 cases, Billroth-II method was used in 3 cases, and Roux-en Y method was used in 198 cases. RGC was diagnosed in 11 of the 405 patients. The median follow-up period was 5 years. The cumulative incidences of RGC calculated by the Kaplan-Meier method were 3.0%, 4.1%, and 10.5% at 5, 10, and 15 years after DG, respectively. During the initial surgery, differentiated type was significantly associated with RGC development [hazard ratio (HR): 4.71, 95% confidence interval (CI): 1.02-21.80, P=0.05]. Male sex (HR: 2.97, 95% CI: 0.64-13.75, P=0.16), old age (≥70 years) (HR: 2.72, 95% CI: 0.78-9.47, P=0.11), and synchronous multiple GC (HR: 1.31, 95% CI: 0.28-6.08, P=0.73) were not associated with RGC development. Patients who have undergone DG for differentiated type GC were statistically significantly associated with developing RGC. Intensive endoscopic surveillance would be needed for the patients who underwent DG for differentiated type GC.

Laparoscopic Function-Preserving Gastrectomy for Proximal Gastric Cancer or Esophagogastric Junction Cancer: A Narrative Review.

Function-preserving procedures to maintain postoperative quality of life are an important aspect of treatment for early gastric cancer. Laparoscopic proximal gastrectomy (LPG) and laparoscopic distal gastrectomy with a small remnant stomach, namely laparoscopic subtotal gastrectomy (LsTG), are alternative function-preserving procedures for laparoscopic total gastrectomy of early proximal gastric cancer. In LPG, esophagogastrostomy with techniques to prevent reflux and double-tract and jejunal interposition including esophagojejunostomy is usually chosen for reconstruction. The double-flap technique is currently a preferred reconstruction technique in Japan as an esophagogastrostomy approach to prevent reflux esophagitis. However, standardized reconstruction methods after LPG have not yet been established. In LsTG, preservation of the esophagogastric junction and the fundus prevents reflux and malnutrition, which may maintain quality of life. However, whether LsTG is an oncologically and nutritionally acceptable procedure compared with laparoscopic total gastrectomy or LPG is a concern. In this review, we summarize the status of reconstruction in LPG and the oncological and nutritional aspects of LsTG as a function-preserving gastrectomy for early proximal gastric or esophagogastric junction cancer.

Advantages of Function-Preserving Gastrectomy for Older Patients With Upper-Third Early Gastric Cancer: Maintenance of Nutritional Status and Favorable Survival.

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 function-preserving 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. 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. 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. 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.

Recent Advances in Sentinel Node Navigation Surgery for Early Gastric Cancer

Maintaining the postoperative quality of life (QOL) while ensuring curability without overtreatment is important in the treatment of early gastric cancer. Postoperative QOL is anticipated to be maintained through minimally invasive function-preserving gastrectomy in early gastric cancer. The concept of the sentinel lymph node (SN) basin is essential to maintain the curability of early gastric cancer using minimally invasive function-preserving gastrectomy. However, additional resection after surgery is difficult to perform in gastric cancer. Thus, the SN basin theory is important. Recently, a multicenter randomized phase III trial in South Korea (SENORITA trial) proved that laparoscopic sentinel node navigation surgery (LSNNS) for stomach preservation results in better postoperative QOL compared with standard gastrectomy in patients with early gastric cancer. LSNNS contributes to patients' QOL based on the concept that curability is not impaired. A multicenter nonrandomized phase III trial is ongoing in Japan, and oncologic safety is expected to be demonstrated. LSNNS has been established as a treatment option for selected patients with early gastric cancer, and its application will become widespread in the future.

Function-Preserving Gastrectomy for Early Gastric Cancer.

Simple SummaryFor patients with early gastric cancer (EGC), a good prognosis is achieved by conventional standard gastrectomy with radical lymphadenectomy. However, postgastrectomy syndrome is often inevitable and results in decreased quality of life (QOL). To improve patients’ QOL, proximal gastrectomy instead of total gastrectomy and pylorus-preserving gastrectomy instead of distal gastrectomy have been widely accepted as function-preserving gastrectomies. Recently, personalized, minimized gastrectomy with sentinel node navigation surgery has been developed and is expected to be an ideal treatment option for patients with EGC. Herein, we review the indications, surgical techniques, and postoperative outcomes of function-preserving gastrectomy.Recently, minimally invasive (endoscopic or laparoscopic) treatment for early gastric cancer (EGC) has been widely accepted. However, a standard gastrectomy with radical lymphadenectomy is generally performed in patients with EGC who have no indications for endoscopic resection, and postgastrectomy dysfunction is one of the problems of standard gastrectomy. Function-preserving gastrectomy, such as proximal gastrectomy and pylorus-preserving gastrectomy, can be considered when attempting to preserve the patient’s quality of life (QOL) postoperatively. In addition, sentinel node navigation surgery for EGC has been applied in clinical practice in several prospective studies on function-preserving personalized minimized gastrectomy. In the near future, the sentinel lymph node concept is expected to form the basis for establishing an ideal, personalized, minimally invasive function-preserving treatment for patients with EGC, which will improve their postoperative QOL without compromising their long-term survival. In this review article, we summarize the current status, surgical techniques, and postoperative outcomes of function-preserving gastrectomy for EGC.

NPTD classification: an updated classification of gastric cancer location for function preserving gastrectomy based on physiological lymphatic flow

BackgroundThe correlation between tumor location and lymphatic flow distribution in gastric cancer has been previously reported, and PTD (Proximal – Transitional – Distal) classification was proposed. Our group updated and developed the nPTD classification.MethodWe retrospectively studied gastric cancer patients who underwent the dye method sentinel node biopsy from 1993 to 2020. The inclusion criteria were a single lesion type 0 cancer of ≤5 cm in the long axis, clinically node-negative, and invasion within the proper muscle layer pathologically. In this study, the distribution of dyed lymphatic flow was evaluated for each occupied area of the tumor.ResultsWe included 416 patients in this study. The tumors located in the watershed of the right and left gastroepiploic arteries near greater curvature had extensive lymphatic flow; therefore, a newly circular region with a diameter of 5 cm is set on the watershed of the greater curvature between P and T zone as the ‘n’ zone. In addition, for cancers located in the lesser P curvature, lymphatic flow to the greater curvature was not observed. Therefore, the P zone was divided into two: the lesser curvature side (PL) and the greater curvature side (PG).ConclusionsThe advantage of the nPTD classification is that it provides not only proper nodal dissection but also adequate function-preserving gastrectomy. If the tumor is localized within the PL, the proximal gastrectomy resection area can be further reduced. In contrast, for cancers located in the ‘n’ zone, near-total gastrectomy is required because of the extensive lymphatic flow.

The Results of Sentinel Node Mapping for Patients with Clinically Early Staged Gastric Cancer Diagnosed with pT2/deeper Tumors.

Sentinel node (SN) mapping based on the SN concept has been applied to early gastric cancer. However, it is still controversial whether or not the oncological safety is ensured in case pathological stage was advanced in these patients. The aim of this study was to investigate the validity of SN mapping in patients with clinically early staged gastric cancer diagnosed with pT2/deeper tumors. We retrospectively analyzed 40 patients with a diagnosis of cT1N0 or cT2N0 single-lesion gastric cancer who were shown to have pT2 or deeper tumors after gastrectomy with SN mapping. We adopted a dual-tracer method using a radioactive colloid and blue dye to detect SNs. The diagnostic accuracy and distribution of SNs at each tumor site were analyzed. Of the 40 patients, 24 (60%) were postoperatively diagnosed as pT2, and 16 (40%) as pT3 or T4. SNs were detected in all patients. The false negative rate was 9% (1/11), and in that patient, the non-SN metastasis was observed within the SN basin. Diagnostic accuracy was 98% (39/40). Overall distribution of SNs was similar to that for patients with early gastric cancer. No significant differences in overall and recurrence-free survival were observed between the patients who underwent standard gastrectomy and those who underwent function-preserving gastrectomy, based on the results of SN mapping. Our results confirmed validity of SN mapping for patients with clinically early staged gastric cancer diagnosed with pT2/deeper tumors after gastrectomy. Closed surveillance without additional surgical treatment is an option for these patients.

Chinese expert consensus on function-preserving gastrectomy for gastric cancer (2021 edition)

With the development of surgical treatment for gastric cancer, under the premise of ensuring the effect of surgical treatment, the objectives of preserving the function of stomach, diminishing the influence of quality of life and keeping the outcome of treatment, are the expectation of patients and the goal of surgeons. The emerge of function-preserving gastrectomy (FPG) indicates that the surgical treatment of gastric cancer steps into the individualized and precision era. Because the concept and operation procedures of FPG have not achieved consensus, the Gastrointestinal Surgery Branch, Surgery Branch, Chinese Medical Association (CMA) with Chinese Society of Surgical Oncology of Chinese Medical Doctor Association(CMDA), Chinese Society of Upper Gastrointestinal Surgeon of CMDA, Stomach and Intestines Committee of Chinese Anticancer Association, convenes some experts to summarize the recent literatures and discuss to reach the consensus about the FPG in the treatment of early gastric cancer. The definition of FPG is as follows: without compromising the oncological efficacy of early gastric cancer, decrease of the operational scale, selection of optimal reconstruction procedures and preservation of the gastric function as much as possible. The most common operation methods are procedures of minimized scale (pylorus-preserving gastrectomy, segmental gastrectomy, local gastrectomy and endoscopic resection) and proximal gastrectomy (PG). Besides the anastomosis of esophagus and gastric remnants, the reconstruction method after proximal gastrectomy also includes tubular gastroesophagostomy, double tract reconstruction, Interposition jejunostomy, side to side gastroesophagostomy (SOFY), double flap gastroesophagostomy (Kamikawa anastomosis), etc. The evaluation of gastric function after FPG includes the assessment of gastric remnant function, the functional complications and the nutritional status. We believe the publication of consensus will properly popularize FPG, promote further research about the gastric cancer and function of gastric remnant, and improve the theoretical study about FPG. Moreover, the indications and procedures of FPG will be broadened and renovated.

Functional evaluation after function-preserving gastrectomy

With the increase of people's health awareness and the progress of medical diagostic technology in recent years, the diagnosis rate of early gastric cancer is increasing year by year. Although radical surgery has good efficacy, how to maximize the preservation of the normal anatomy and function of the stomach and improve the quality of life of patients in the pursuit of radical surgery has become a more important issue in the treatment of early gastric cancer. Under the condition of ensuring radical lymph node dissection, function-preserving gastrectomy can fully preserve gastric function by reducing the resection extent and preserving the pylorus and the vagus nerve, which has advantage of improving quality of life and has great potential in the treatment of early gastric cancer. However, there is no functional evaluation standard for function-preserving gastrectomy at present. Most of the patients are evaluated by quality of life scale, which is relatively subjective. Even though the evaluation of endoscopy, hematology and other objective means can indicate the benefit degree in quality of life brought by functional reconstruction, the evidence level is limited. Therefore, this paper discusses the research status of function-preserving gastrectomy evaluation, postoperative complications, postoperative nutritional status, auxiliary examination and other items in the evaluation of gastric function, and analyzes the prospects of research direction in this field.

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.

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.

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.

Current status of function-preserving gastrectomy for gastric cancer.

Early gastric cancer (EGC) has excellent postoperative survival outcomes; thus, one of the recent keywords in the treatment of EGC is “function‐preserving gastrectomy (FPG).” FPG reduces the extent of lymphadenectomy and gastric resection without compromising the long‐term prognosis. Proximal gastrectomy (PG) is an alternative to total gastrectomy (TG) for EGC in the upper‐third of the stomach, in which the gastric reservoir, gastric acid secretion, and intrinsic factors are maintained. Distal gastrectomy (DG) with a small remnant stomach, namely subtotal gastrectomy (STG), is another option for upper EGC, where the function of the cardia and fundus is preserved. Pylorus‐preserving gastrectomy (PPG) is a good alternative to DG for EGC in the middle‐third of the stomach, where pyloric function is preserved. Following elucidation of the markedly low incidences of possible metastasis to lymph node stations where dissection is omitted, the oncological safety of these FPG procedures was clarified. Nutritional advantages of PG or STG over TG have been reported; however, the standardized reconstruction methods after PG are yet to be established, and it is important to devise methods to prevent postoperative gastroesophageal reflux and anastomotic complications regardless of the reconstruction method. Nutritional benefits of PPG compared with DG have also been clarified, in which reducing postoperative gastric stasis is important. For the further spread of these FPG procedures, several issues, such as precise evaluation of preserved function, confirmation of oncological safety, and standardization of the technique, should be addressed in future prospective randomized controlled trials.

Recent updates and current issues of sentinel node navigation surgery for early gastric cancer.

With the increase in the incidence of early gastric cancer (EGC), several endoscopic and laparoscopic approaches, such as endoscopic submucosal dissection and function-preserving gastrectomy, have been accepted as standard treatments. Sentinel node navigation surgery (SNNS) is an ideal surgical option for preservation of most parts of the stomach and consequent maintenance of normal gastric function to improve quality of life in patients with EGC. Although many previous studies and clinical trials have demonstrated the safety and feasibility of the sentinel node concept in gastric cancer, the clinical application of SNNS is debatable. Several issues regarding technical standardization and oncological safety need to be resolved. Recently several studies to resolve these problems are being actively performed, and SNNS might be an important surgical option in the treatment of gastric cancer in the future.

Laparoscopic surgery for gastric cancer: Current status and future direction.

Gastric cancer is still a major cause of death worldwide. While laparoscopic gastrectomy (LG) has gained evidence as a standard treatment for early gastric cancer in the distal stomach, there are still concerns regarding its application for gastric cancer in the upper stomach and advanced gastric cancer. Nevertheless, LG has shown to have faster recovery, shorter hospital stay, less pain, and less blood loss in many retrospective and prospective studies. The application of LG has now extended from conventional radical gastrectomy to novel approaches such as function-preserving gastrectomy and sentinel-node navigated surgery. Studies on the use of laparoscopy in treatment for stage IV gastric cancer are rare, but show that there may be some roles of LG in selected cases. With the development of new laparoscopic tools that augment human ability, the future of LG should move on from proving non-inferiority to demonstrating superiority compared to the traditional open gastrectomy.

Significance of celiac branch of the vagal nerve in function-preserving gastrectomy

Function-preserving gastrectomy, especially pylorus-preserving gastrectomy (PPG), can improve the quality of life and has been widely recognized. With the development of surgical techniques and equipment, nerve preservation has become a new requirement in the era of "precision medicine", but the preservation of celiac branch of the vagal nerve remains controversial in gastric cancer surgery. Current researches have shown that the preservation of celiac branch of the vagal nerve is safe and feasible in patients with early gastric cancer. Although controversial, nerve preservation may play a role in preventing gallstones, regulating gastric emptying, reducing dumping syndrome, alleviating chronic diarrhea, reducing gastroesophageal reflux, and inhibiting bile reflux. The significance of the celiac branch of the vagal nerve in gastric cancer surgery is worth further attention and exploration to promote the development of function-preserving gastrectomy and improve the quality of life of patients.

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.

The incidences of metachronous multiple gastric cancer after various types of gastrectomy: analysis of data from a nationwide Japanese survey

BackgroundThe incidence of metachronous multiple gastric cancer (MMGC) after gastrectomy remains unclear. This study evaluated the incidences of MMGC according to specific gastrectomy types, including pylorus-preserving gastrectomy (PPG), proximal gastrectomy (PG), and function-preserving gastrectomy (FPG), which was categorized as segmental gastrectomy and local resection.MethodsWe conducted a questionnaire survey of the Japanese Society for Gastro-Surgical Pathophysiology members, who were asked to report their institutional numbers of radical gastrectomy cases for cancer between 2003 and 2012. The cases were categorized according to whether the remnant stomach’s status was followed for > 5 years, confirmation of MMGC, time to diagnosis, and treatment for MMGC. We calculated the “precise incidence” of MMGC by dividing the number of MMGC cases by the number of cases in which the status of remnant stomach was followed up for > 5 years.ResultsThe responses identified 33,731 cases of gastrectomy. The precise incidences of MMGC were 2.35% after distal gastrectomy (DG), 3.01% after PPG, 6.28% after PG (p < 0.001), and 8.21% after FPG (p < 0.001). A substantial proportion of MMGCs (36.4%) was found at 5 years after the initial surgery. The rates of MMGC treatment using endoscopic submucosal dissection were 31% after DG, 28.6% after PPG, 50.8% after PG (p < 0.001), and 67.9% after FPG (p < 0.001).ConclusionsThe incidence of MMGC was 2.4% after DG, and higher incidences were observed for larger stomach remnants. However, the proportion of cases in which MMGC could be treated using endoscopic submucosal dissection was significantly higher after PG and FPG than after DG.