Length of the antral segment in pylorus-preserving gastrectomy

Antral Preservation in Sleeve Gastrectomy Appears to Protect Against Prolonged Vomiting and Gastroesophageal Reflux Disease. A Meta-Analysis of Randomized Controlled Trials

The optimal distance between the starting point of gastric transection and the pylorus during laparoscopic sleeve gastrectomy (LSG), which can be referred to as the distance from pylorus (DFP), is controversial. No consensus exist for what DFP is considered antral preservation, and what DFP is considered antral resection. Some surgeons prefer shorter DFP to maximize excess weight loss percentage (EWL%), while others prefer longer DFP because they believe that it shortens length of stay (LOS) and protects against leaks, prolonged vomiting, and gastroesophageal reflux disease (GERD). We sought to compare 6-cm DFP and 2-cm DFP in postoperative outcomes. In addition, we sought to evaluate the magnitude of any observed benefit through number needed to treat (NNT) analysis.

Modern surgical therapy for gastric cancer-Robotics and beyond

The surgical paradigm for gastric cancer has been changed from extended surgery to minimally invasive surgery. Laparoscopic surgery is a practical method for minimally invasive surgery for early gastric cancer, and the indication is expanding to advanced gastric cancer. In recent years, robotic gastrectomy has been highlighted as a breakthrough to overcome the drawbacks of laparoscopic gastrectomy. Here, we discuss the recent updates of modern surgical therapy for gastric cancer-robotics and beyond.

Function-Preserving Gastrectomy for Early Gastric Cancer

Simple Summary

For 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.

Abstract

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.

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.

Radiologic intervention due to delayed gastric emptying after pylorus preserving gastrectomy for gastric cancer does not affect pyloric function

Purpose

The purpose of this study is to evaluate whether radiologic intervention in the pylorus decreases its function for delayed gastric emptying (DGE) patients after pylorus preserving gastrectomy (PPG) for gastric cancers and to determine the optimal interventional algorithm.

Methods

PPG patients who underwent intervention for DGE from January 2013 to December 2017 and a control group using propensity score matching were identified. Pyloric function was compared by subjective symptoms, postoperative upper gastrointestinal series at 3 months (short-term function), and esophagogastroduodenoscopy findings at 12 months (long-term function). Serum albumin levels and body weight change, 6 months and 12 months postoperatively, were compared to evaluate nutritional status. Interventional success rate, mean hospital stay, and recurrence of DGE were analyzed to determine the optimal intervention plan.

Results

Fifty-one out of 677 patients (7.53%) received intervention. There was no difference in pyloric function and nutritional status between the intervention and control groups. The interventional success rate for first-time balloon dilatation was 41.7% (20/48). If a second intervention was required and balloon dilatation was done, the success rate was 45.5% (5/11). However, if stent insertion was done, the success rate was 100% (17/17). Subsequent stent insertion after balloon dilatation resulted in a shorter mean hospital stay. Intervention including stent insertion had a lower recurrence of DGE than balloon only intervention (1.96% vs. 5.88%, P=0.041).

Conclusion

Radiologic intervention did not decrease long-term pyloric function. For treating DGE, if at first balloon dilatation fails, retrievable stent insertion can be considered as a second choice.

A comparison between pylorus-preserving and distal gastrectomy in surgical safety and functional benefit with gastric cancer: a systematic review and meta-analysis

BACKGROUND

Due to better functional outcomes, pylorus-preserving gastrectomy (PPG) has been widely applied for early gastric cancer (EGC) patients as an alternative to distal gastrectomy (DG). However, controversies still persist regarding the surgical efficacy and oncological safety of PPG.

METHODS

Original studies comparing PPG and DG for EGC were searched in PubMed, Embase, and the Cochrane Register of Controlled Trials up to December 2019. The weight mean difference, standardized mean difference, or odds risk was used to calculate the short-term and long-term outcomes between the two groups.

RESULTS

Twenty-one comparative studies comprising 4871 patients (1955 in the PPG group and 2916 in the DG group) were enrolled in this systematic review and meta-analysis. PPG showed longer hospital day, decreased harvested lymph nodes, and more delayed gastric emptying. However, PPG had the benefits of lower incidence of anastomosis leakage, early dumping syndrome, gastritis and bile reflux, and better recovery of total protein, albumin, hemoglobin, and weight. No difference was found in operative time, blood loss, and overall complications. Moreover, the long-term survival and recurrence rate were similar in two groups.

CONCLUSION

Owing to the non-inferiority of surgery and oncology outcomes and the superiority of function outcomes in PPG, we revealed that PPG can be clinically applicable instead of DG in EGC. However, more high-quality comparative studies and randomized clinical trials would be required for further confirmation.

Influence of antrum size on gastric emptying and weight-loss outcomes after laparoscopic sleeve gastrectomy (preliminary analysis of a randomized trial)

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) has increased in popularity in recent years as a definitive bariatric procedure. Despite its growing popularity worldwide, the surgical technique is not well standardized. There is a lack of evidence on the matter of the antrum size and its relation to gastric emptying and weight-loss outcomes. The aim of the study is to evaluate the influence of antrum size over gastric emptying and weight-loss outcomes.

METHODS

Twenty-five patients were prospectively randomized according to the distance between the first firing and the pylorus: AR group (antrum resection-2 cm from the pylorus) and AP group (antrum preservation-5 cm from the pylorus). Gastric emptying (%GE) was evaluated by a gastric emptying scintigraphy before surgery, 2 months and 1 year after LSG. Antrum volume was measured using a MultiSlice CT Scan performed 2 months and 1 year after surgery. The percent of excess weight loss (%EWL) was calculated after 1 year follow-up.

RESULTS

At 2 months after LSG the mean %GE was 69.7 ± 18 in the AR group and 72.8 ± 20 in the AP group (p = 0.69). At 1 year it was 66.5 ± 21 and 74.2 ± 16 in the AR and AP groups, respectively (p = 0.30). A significant accelerated gastric emptying was observed at 2 months (p = 0.025) and at 1 year (p = 0.013) in the AP group. Meanwhile in the AR group this increase was not significant (p = 0.12 at 2 months and p = 0.21 at 1 year). Differences regarding the %EWL between groups were no statistically significant (p = 0.74).

CONCLUSIONS

After LSG there is a global tendency to an accelerated gastric emptying, although only significant in the antrum preservation group; however, no differences were observed regarding the %EWL between groups after 1 year follow-up.

Function-preserving gastrectomy for gastric cancer in Japan

Surgery used to be the only therapy for gastric cancer, and since its ability to cure gastric cancer was the focus of attention, less attention was paid to function-preserving surgery in gastric cancer, though it was studied for gastroduodenal ulcer. Maki et al developed pylorus-preserving gastrectomy for gastric ulcer in 1967. At the same time, the definition of early gastric cancer (EGC) was being considered, histopathological investigations of EGC were carried out, and the validity of modified surgery was sustained. After the development of H2-blockers, the number of operations for gastroduodenal ulcers decreased, and the number of EGC patients increased simultaneously. As a result, the indications for pylorus-preserving gastrectomy for EGC in the middle third of the stomach extended, and various alterations were added. Since then, many kinds of function-preserving gastrectomies have been performed and studied in other fields of gastric cancer, and proximal gastrectomy, jejunal pouch interposition, segmental gastrectomy, and local resection have been performed. On the other hand, from the overall perspective, it can be said that endoscopic resection, which was launched at almost the same time, is the ultimate function-preserving surgery under the current circumstances. The current function-preserving gastrectomies that are often performed and studied are pylorus-preserving gastrectomy and proximal gastrectomy. The reasons for this are that these procedures that can be performed with systemic lymph node dissection, and they include three important elements: (1) reduction of the extent of gastrectomy; (2) preservation of the pylorus; and (3) preservation of the vagal nerve. In addition, these operations are more likely to be performed with a laparoscopic approach as minimally invasive surgery. Of the above-mentioned three elements, reduction of the extent of gastrectomy is the most important in our view. Therefore, we should try to reduce the extent of gastrectomy if curability of the gastric cancer can still be achieved. However, if we preserve a wider residual stomach in function-preserving gastrectomy, we should pay attention to the development of metachronous gastric cancer.

Pylorus-Preserving Gastrectomy for Gastric Cancer

Pylorus-preserving gastrectomy (PPG) is a function-preserving surgery for the treatment of early gastric cancer (EGC), aiming to decrease the complication rate and improve postoperative quality of life. According to the Japanese gastric cancer treatment guidelines, PPG can be performed for cT1N0M0 gastric cancer located in the middle-third of the stomach, at least 4.0 cm away from the pylorus. Although the length of the antral cuff gradually increased, from 1.5 cm during the initial use of the procedure to 3.0 cm currently, its optimal length still remains unclear. Standard procedures for the preservation of pyloric function, infra-pyloric vessels, and hepatic branch of the vagus nerve, make PPG technically more difficult and raise concerns about incomplete lymph node dissection. The short- and long-term oncological and survival outcomes of PPG were comparable to those for distal gastrectomy, but with several advantages such as a lower incidence of dumping syndrome, bile reflux, and gallstone formation, and improved nutritional status. Gastric stasis, a typical complication of PPG, can be effectively treated by balloon dilatation and stent insertion. Robot-assisted pylorus-preserving gastrectomy is feasible for EGC in the middle-third of the stomach in terms of the short-term clinical outcome. However, any benefits over laparoscopy-assisted PPG (LAPPG) from the patient's perspective have not yet been proven. An ongoing Korean multicenter randomized controlled trial (KLASS-04), which compares LAPPG and laparoscopy-assisted distal gastrectomy for EGC in the middle-third of the stomach, may provide more clear evidence about the advantages and oncologic safety of PPG.

Factors that minimize postgastrectomy symptoms following pylorus-preserving gastrectomy: assessment using a newly developed scale (PGSAS-45)

BACKGROUND

Pylorus-preserving gastrectomy (PPG) is sometimes performed as a function-preserving surgery for the treatment of early gastric cancer. The aim of this study was to use an integrated assessment scale for postgastrectomy syndrome to determine the appropriate indicators and optimal methods for PPG.

METHODS

The Postgastrectomy Syndrome Assessment Study (PGSAS) is a multicenter survey based on an integrated questionnaire (PGSAS-45) consisting of 45 items. Questionnaire responses were retrieved from a total of 2,520 patients, each of whom had undergone one of six different types of gastrectomy procedures; 313 responses from patients who had received PPG were analyzed here.

RESULTS

The size of the proximal gastric remnant (less than one-quarter, about one-third, or more than one-half of the original size) significantly influenced the change in body weight, the scores for dissatisfaction at the meal, and dissatisfaction for daily life subscale (P = 0.030, P = 0.005, P = 0.034, respectively). The nausea score in patients who underwent hand-sewn anastomosis was significantly lower than in those who underwent anastomosis with a linear stapler (P = 0.006). The scores for diarrhea subscale, increased passage of stools, and sense of foods sticking differed significantly depending on the length of the preserved pyloric cuff (P = 0.047, P = 0.021, P = 0.046, respectively).

CONCLUSIONS

The results suggest that preservation of a sufficient proximal gastric remnant is recommended when utilizing PPG as function-preserving surgery.

Totally laparoscopic pylorus-preserving gastrectomy for early gastric cancer in the middle stomach: technical report and surgical outcomes

INTRODUCTION

The feasibility, safety, and improved quality of postoperative life following laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) with a hand-sewn anastomosis via a mini-laparotomy for early gastric cancer (EGC) have been previously established. Here we describe the surgical procedure of totally laparoscopic pylorus-preserving gastrectomy (TLPPG) using an intracorporeal delta-shaped anastomosis technique, and the short-term surgical outcomes of 60 patients with EGC in the middle stomach are reported.

METHODS

After lymphadenectomy and mobilization of the stomach, intraoperative gastroscopy was performed in order to verify the location of the tumor, and then the distal and proximal transecting lines were established, 5 cm from the pyloric ring and just proximal to Demel's line, respectively. Following transection of the stomach, a delta-shaped intracorporeal gastrogastrostomy was made with linear staplers.

RESULTS

There were no intraoperative complications or conversions to open surgery. Mean operation time and blood loss were 259 min and 28 mL, respectively. Twelve patients (20.0%) experienced postoperative complications classified as grade II using the Clavien-Dindo classification, with the most frequent complication being gastric stasis (6 cases, 10.0 %). The incidence of severe complications classified as grade III or above was 1.7%; only one patient required reoperation and intensive care due to postoperative intraabdominal bleeding and subsequent multiple organ failure.

CONCLUSION

TLPPG with an intracorporeal delta-shaped anastomosis was found to be a safe procedure, although it tended to require a longer operating time than the well-established LAPPG with a hand-sewn gastrogastrostomy.

Residual gastric volume estimated with a new radiological volumetric model: relationship with weight loss after laparoscopic sleeve gastrectomy

BACKGROUND

The volume of the gastric reservoir appears crucial to explain the success of laparoscopic sleeve gastrectomy (LSG) in the treatment of morbid obesity. The aims of this study were to describe a new, easy model to estimate gastric reservoir volume after LSG; to evaluate the volumetric changes 1 year after surgery; and to analyze their relationship with weight loss.

METHODS

This is a prospective observational study of all patients undergoing LSG in the Department of Surgery at our institution. The gastric reservoir was evaluated radiologically considering the image as a complex geometrical shape with two components: a cylinder (gastric body) and a truncated cone (antrum). Radiologic assessment using this new model was performed at 1 and 12 months after surgery. Moreover, body mass index and percentage of excess weight loss (%EWL) were evaluated at 3, 6, 12, and 18 months after LSG.

RESULTS

Forty-five patients (34 F/11 M) with a mean age of 46.9 years were included. A significant increase in total gastric reservoir volume (124.8 ± 58.7 and 188.6 ± 76.4 mL at 1 and 12 months, respectively; p = 0.001) was observed. No statistically significant differences were observed comparing volume of the two components at the two time points. The %EWL at 18 months was inversely correlated with reservoir volume changes at 12 months after LSG (p = 0.006).

CONCLUSIONS

We describe an easy volumetric model to estimate the size of the gastric reservoir after LSG. Moreover, a direct relationship between an increase in gastric reservoir volume and a lower weight loss after surgery was documented.

Feasibility and functional efficacy of distal gastrectomy with jejunal interposition for gastric cancer: a case series

INTRODUCTION

Distal gastrectomy with jejunal interposition (DGJI) has been used in our institution for selected patients with gastric cancer as a function-preserving gastrectomy. The aim of this retrospective study was to clarify the feasibility and functional efficacy of DGJI.

METHODS

A retrospective analysis was performed in 61 patients who underwent DGJI between 2002 and 2011.

RESULTS

Mean operation time was 393.8 min and blood loss was 463.3 ml. Postoperative early major complications developed in 2 (3.3%) patients. The most common complication was gastric stasis, occurring in 7 (11.5%) patients. All patients with complications recovered with conservative treatment, and no operative mortality occurred. Endoscopy 1 year after operation revealed reflux gastritis in 1 patient. Reflux esophagitis was not found in any patient. However, anastomotic ulcer was found in 12 (22.2%) patients over the 1-year period after operation. No patient reported symptoms of early and late dumping syndrome, and 1 (1.9%) patient self-reported diarrhea.

CONCLUSIONS

DGJI was a feasible and safe procedure with several advantages in terms of less incidence of reflux gastritis and esophagitis, dumping syndrome and diarrhea. However, this procedure is complicated and time-consuming, and it is necessary to be aware of the potential occurrence of an anastomotic ulcer at the site of the gastrojejunostomy after DGJI.

Radical resection of the pyloric antrum and its effect on gastric emptying after sleeve gastrectomy

BACKGROUND

The surgical technique of laparoscopic sleeve gastrectomy (LSG) has not been fully standardized yet and there is the unresolved question of what is the optimum size of retained pyloric antrum. The aim of our research was to prove that even after a radical resection of the pyloric antrum the physiological stomach evacuation function can still be preserved.

METHODS

Our study was based on 12 patients, who were randomly divided into two groups. Patients undergoing radical antrum resection (RA group) underwent gastric emptying scintigraphy to determine the evacuation half-time (T1/2) and food retention in the 90th minute of the test (%GE) both before the operation and 3 months afterward. Patients in whom the antrum was preserved (PA group) served as a control group for comparison of postoperative weight loss (in kilogram), decrease in body mass index (BMI), and decline in excess weight (%EWL). The resulting changes were statistically processed.

RESULTS

In the RA group, the average time T1/2 declined from 57.5 to 32.25 min (p = 0.016) and average retention %GE dropped from 20.5 to 9.5% (p = 0.073). Differences in the average values of weight, BMI, or %EWL between both groups were of no statistical significance (p > 0.8).

CONCLUSIONS

In the RA group, an increase in gastric emptying postoperatively was noted. Complications such as failure of stomach evacuation were not observed in the RA group. Our results suggest that even more radical resection of the pyloric antrum performed by LSG is possible without concerns of postoperative disorder of the stomach evacuation function.

Function-preserving gastrectomy for early gastric cancer

The number of early gastric cancer (EGC) cases has been increasing because of improved diagnostic procedures. Applications of function-preserving gastric cancer surgery may therefore also be increasing because of its low incidence of lymph node metastasis, excellent survival rates, and the possibility of less-invasive procedures such as laparoscopic gastrectomy being used in combination. Pylorus-preserving gastrectomy (PPG) with radical lymph node dissection is one such function-preserving procedure that has been applied for EGC, with the indications, limitations, and survival benefits of PPG already reported in several retrospective studies. Laparoscopy-assisted proximal gastrectomy has also been applied for EGC of the upper third of the stomach, although this procedure can be associated with the 2 major problems of reflux esophagitis and carcinoma arising in the gastric stump. In the patient with EGC in the upper third of the stomach, laparoscopy-assisted subtotal gastrectomy with a preserved very small stomach may provide a better quality of life for the patients and fewer postoperative complications. Finally, the laparoscopy endoscopy cooperative surgery procedure combines endoscopic submucosal dissection with laparoscopic gastric wall resection, which prevents excessive resection and deformation of the stomach after surgery and was recently applied for EGC cases without possibility of lymph node metastasis. Function-preserving laparoscopic gastrectomy is recommended for the treatment of EGC if the indication followed by accurate diagnosis is strictly confirmed. Preservation of remnant stomach sometimes causes severe postoperative dysfunctions such as delayed gastric retention in PPG, esophageal reflux in PG, and gastric stump carcinoma in the remnant stomach. Moreover, these techniques present technical difficulties to the surgeon. Although many retrospective studies showed the functional benefit or oncological safety of function-preserving gastrectomy, further prospective studies using large case series are necessary.

Questionnaire survey regarding the current status and controversial issues concerning reconstruction after gastrectomy in Japan

The Japanese Society for the Study of Postoperative Morbidity after Gastrectomy conducted a nationwide questionnaire survey to clarify the current status of reconstruction after gastrectomy. One hundred and forty-five institutions (66%) responded to the survey. The questionnaire dealt with the reconstruction after a distal gastrectomy, pylorus-preserving gastrectomy (PPG), total gastrectomy, and proximal gastrectomy. The most common method of reconstruction after distal gastrectomy was Billroth I in 112 institutions (74%), and Roux-en-Y (RY) in 30 (21%). Seventy-seven institutions (53%) responded to the PPG questions. The lengths of the antral cuff were widely distributed among the institutions. Segmental gastrectomy was performed by 23 institutions for limited cases. The most common method of reconstruction after total gastrectomy was RY in 138 institutions (95%). Reconstruction with a pouch after total gastrectomy was done in 26 institutions (18%). The most common reconstructions after proximal gastrectomy were esophagogastrostomy in 69 institutions (48%), jejunal interposition in 41 (28%), double tract in 19 (13%) and pouch reconstruction in 6 (7%). Although most Japanese surgeons are concerned about the revised methods of reconstruction and quality of life after gastrectomy, surgeons have not yet reached a full consensus on these issues.

Large-scale investigation into dumping syndrome after gastrectomy for gastric cancer

BACKGROUND

The aim of this study was to investigate early and late dumping syndromes in a large number of patients after gastrectomy for gastric cancer.

STUDY DESIGN

Responses to questions on a visual analogue scale survey completed by 1,153 gastrectomy patients were analyzed for associations between clinical factors and occurrence of dumping syndrome. Types of gastrectomy included distal gastrectomy with Billroth I or with Roux-Y reconstruction, pylorus preserving gastrectomy, proximal gastrectomy, and total gastrectomy.

RESULTS

Based on the visual analogue scale rating of symptomatic discomfort, patients were categorized into 1 of 2 groups: symptom-free or symptomatic. Incidences of early or late dumping syndrome in all patients were 67.6% and 38.4%, respectively. Patients in whom early dumping syndrome developed were significantly more likely to experience late dumping syndrome than those in whom it did not develop (p < 0.001). According to multivariate analyses, factors that decreased the risk for developing early dumping syndrome were reduced weight loss (p < 0.01), old age (p < 0.01), pylorus preserving gastrectomy (p < 0.01), distal gastrectomy with Roux-Y reconstruction (p < 0.01), and distal gastrectomy with Billroth I (p = 0.019). In addition, factors that decreased the risk of developing late dumping syndrome were reduced weight loss (p = 0.03), being male (p < 0.01), pylorus preserving gastrectomy (p < 0.01), and distal gastrectomy with Roux-Y reconstruction (p < 0.01). No other clinical factors (lymph node dissection, vagal nerve preservation, and postoperative period) showed a substantial association with the occurrence of dumping syndrome in multivariate analyses.

CONCLUSIONS

Substantially more patients suffered from early dumping syndrome than late dumping syndrome after gastrectomy. Two clinical factors, surgical procedures and amount of body weight loss, associated significantly with the occurrence of both early and late dumping syndrome.

Correlation between the length of the pyloric cuff and postoperative evaluation after pylorus-preserving gastrectomy

BACKGROUND

Recent years have seen the preserved pyloric cuff being lengthened in pylorus-preserving gastrectomy for early gastric cancer. We performed clinical assessment of the symptoms after pylorus-preserving gastrectomy in patients treated at the National Cancer Center Hospital in Japan during the past 9 years.

METHODS

Four hundred and fifty-six patients who had undergone pylorus-preserving gastrectomy and been followed up for at least 3 years were studied. We classified the patients into two groups according to the length of the pyloric cuff (group A, within 3.0 cm; group B, more than 3.0 cm). Medical records were reviewed for further histological and follow-up data. A questionnaire regarding dumping syndrome and gastric stasis was also completed by the patients.

RESULTS

Our results showed no statistically significant differences in symptoms, such as dumping syndrome or emptying disturbances, between the two groups.

CONCLUSION

Our study revealed that the differences in several functions and symptom scales were not pronounced between the two groups. Regardless of the length of the pyloric cuff, pylorus-preserving gastrectomy can be utilized for the treatment of early gastric cancer even if the tumor is located proximal to the middle body.

Evaluation of the adequacy of lymph node dissection in pylorus-preserving gastrectomy for early gastric cancer using the maruyama index

BACKGROUND

The Maruyama computer program predicts the percentage likelihood of disease in lymph node stations left undissected by a surgeon, according to the age and sex of the patient and the gross type, size, location, depth of invasion, and histology of the tumor. The Maruyama index (MI) is defined as the sum of the predictions of the percentage likelihood of disease in undissected regional lymph node station (station 1-12). It has been shown that an MI < 5 is a strong predictor of survival and that the MI is an independent predictor of overall survival and relapse risk. We used the MI to evaluate the adequacy of lymph nodes dissection in pylorus-preserving gastrectomy (PPG) for early gastric cancer (EGC) performed at Seoul National University Hospital.

METHODS

From March 2003 to September 2007, PPG was performed for patients with EGC of the middle third of the stomach when the distal resection margin was greater than 2 cm and preservation of 3 cm antral segment was possible. MIs and pathologic data such as TNM stage and the presence of metastatic lymph node for each station were reviewed.

RESULTS

PPG were performed on 24 patients. The mean age of the patients was 55 years. The median tumor size was 2.1 cm. The median and mean MI were 0 and 0.8, respectively. There were 23 cases of T1N0M0 tumor and one case of T2N0M0 tumor postoperatively. There were no recurrences (mean follow-up period: 27.2 months).

CONCLUSIONS

The MI indicates that lymph node dissection during PPG performed in these 24 patients was adequate.

Transectional gastrectomy: an old but renewed concept for early gastric cancer

Segmental resection of the stomach was first described at the end of the 19th century by Mikulicz, who devised it to preserve the pylorus when performing gastric ulcer surgery. Although this technique was abandoned because of delayed gastric emptying, in 1967 Maki et al. developed a new improved concept of segmental gastrectomy: pylorus-preserving gastrectomy (PPG). The dramatic decrease in the occurrence of gastric ulcers limited the opportunity to perform these operations; however, PPG was then used for treating early gastric cancer, the incidence of which has increased remarkably over the last two decades. From the viewpoint of surgical oncology, a rationale to justify reducing the range of lymphadenectomy is required for preserving the curability. Therefore, we devised a new technique of transectional gastrectomy using sentinel node navigation for early gastric cancer located in the middle third of the stomach. The results of a questionnaire about postoperative symptoms and endoscopic assessment indicated the superiority of transectional gastrectomy over conventional distal gastrectomy. Future confirmation of the sentinel node concept through a multi-institutional validation study conducted by the Japanese Society of Sentinel Node Navigation Surgery would lead to widespread adoption of transectional gastrectomy.

The safety of the dissection of lymph node stations 5 and 6 in pylorus-preserving gastrectomy

BACKGROUND

This study was intended to examine the safety of possibly incomplete dissection of lymph node stations (LNS) 5 and 6 in pylorus-preserving gastrectomy (PPG) for gastric cancer.

MATERIALS AND METHODS

We reviewed the medical information from 1802 gastric cancer patients who underwent curative gastrectomy and whose lymph nodes were topographically classified according to LNS between March 2003 and December 2008. We divided the patients who underwent subtotal gastrectomy into 2 groups according to the distance between the distal resection margin (DRM) and primary tumor: those with a distance of < 6 cm (the < 6 DRM group) and those with a distance of >or= 6 cm (the >or= 6 DRM group). We analyzed the lymph node metastasis rate to LNS 5 and 6 according to T stage and the location. The number of retrieved lymph nodes according to LNS was compared between subtotal gastrectomy (STG) and PPG.

RESULTS

The metastasis rate to LNS 5 was very rare in >or= 6 DRM group: T1a, 0% (0 of 105); T1b, 0.9% (1 of 113); and T2a, 0% (0 of 56), although the number of retrieved LNS 5 was significantly lower in PPG than in STG. The metastasis rate to LNS 6 in the >or= 6 DRM group was significantly lower than in the < 6 DRM group, but higher than that of LNS 5: T1a, 0% (0 of 107); T1b, 1.8% (2 of 114); and T2a, 3.6% (2 of 56). The number of retrieved LNS 6 was not significantly different between STG and PPG.

CONCLUSIONS

PPG seems to be safe for early gastric cancer located >or= 5 cm from the pylorus in terms of LNS 5 and 6.

PTD classification: proposal for a new classification of gastric cancer location based on physiological lymphatic flow

BACKGROUND

We propose a new classification for the location of gastric cancer - the PTD classification (i.e., zones P, T, and D; see below), with the zones classified according to the physiological lymphatic flow.

METHODS

Three hundred and thirty-six patients with T1 or small T2 gastric cancer who underwent sentinel node mapping at our hospital were enrolled. The relationship between the location of the gastric cancer and the physiological lymphatic flow derived from sentinel node mapping was investigated. Lymphatic basins were defined as lymphatic zones divided by the stream of stained lymphatic canals.

RESULTS

One hundred and forty-six patients underwent standard gastrectomy with more than D2 dissection and the other 190 patients underwent function-preserving gastrectomy with the omission of lymph node dissection outside the lymphatic basin. In the former group, the progression pattern of lymph node metastasis was observed; nodal metastasis occurred in sentinel nodes first, and rarely extended outside the lymphatic basin. In the latter group, none of the patients have had a recurrence. The PTD classification we propose is as follows: the dividing line between the proximal region (zone P) and the transitional region (zone T) is the line that links the point of the watershed between the left gastroepiploic artery and right gastroepiploic artery, to the point that is the inflow point of the first descending branch of the left gastric artery; and the dividing line between zone T and the distal region (zone D) is an arc at a radius of 8 cm from the pylorus. There were no lymphatic basins within the right gastric artery area for tumors located in zone T.

CONCLUSION

The advantage of the PTD classification is that if the PTD classification were to be used as a guide for gastric resection procedures, preservation of the pylorus would become possible without diminishing the prognosis in patients with cT1N0 cancer located in zone T.

Outcome of pylorus-preserving gastrectomy for early gastric cancer

Background

Pylorus-preserving gastrectomy has been introduced as a function-preserving operation for early gastric cancer in Japan. The aim of this study was to investigate the safety and radicality of the procedure.

Methods

Between 1995 and 2004, 611 patients with apparent early gastric cancer in the middle third of the stomach had pylorus-preserving gastrectomy. The short-term surgical and long-term oncological outcomes of these operations were assessed.

Results

The accuracy of preoperative diagnosis of early gastric cancer was 94·3 per cent. Nodal involvement was seen in 62 patients (10·1 per cent). There were no postoperative deaths. Complications developed in 102 patients (16·7 per cent). Major complications, such as leakage and abscess, were observed in 19 (3·1 per cent). The most common complication was gastric stasis, occurring in 49 (8·0 per cent). The overall 5-year survival rate in patients with early gastric cancer was 96·3 per cent.

Conclusion

Pylorus-preserving gastrectomy is a safe operation with an excellent prognosis in patients with early gastric cancer. It is recommended as the standard procedure for early gastric cancer in the middle third of the stomach.

Laparoscopy-assisted pylorus-preserving gastrectomy: preservation of vagus nerve and infrapyloric blood flow induces less stasis

BACKGROUND

Pylorus-preserving gastrectomy (PPG) prevents postprandial symptoms; however, delayed gastric retention due to aberrant pylorus function can occur during the early postoperative period. This study aimed to establish a stasis-less PPG procedure with preservation of the vagal nerve and blood flow to the pyloric cuff, and to apply the technique for laparoscopy-assisted PPG.

METHODS

Ninety patients with T1 gastric cancer located in the middle third of the stomach were enrolled in this study for surgery from January 2003 to March 2006, undergoing either laparoscopy-assisted PPG (LAPPG; 39 patients) or conventional PPG (CPPG; 51 patients). Operative and early postoperative outcomes were compared between the two groups.

RESULTS

Relatively low rates of gastric stasis were observed in both the LAPPG (8%) and CPPG (6%) groups. Estimated blood loss in LAPPG (65.4 +/- 12.3 ml) patients was significantly lower than in the CPPG group (160.7 +/- 19.6 ml) (p < 0.001), and the total number of dissected lymph nodes was significantly greater in the LAPPG group (36.2 +/- 1.8) than in the CPPG group (29.0 +/- 1.3) (p = 0.001).

CONCLUSIONS

A PPG procedure with less postoperative stasis and adequate lymph node retrieval was established and applied successfully in laparoscopy-assisted surgery.

Function-preserving surgery for gastric cancer

Early gastric cancer (EGC) with 5-year survival rates exceeding 90% now accounts for nearly 50% of all gastric cancers treated at major institutions in Japan. D2 lymphadenectomy with resection of at least two-thirds of the stomach has been the mainstay of treatment for every stage of gastric cancer, including EGC. Post-gastrectomy syndrome is inevitable after surgery. Most of the symptoms resolve with time, though some patients suffer immensely for prolonged periods. Mucosal cancers rarely metastasize (3% or less). Surgeons have altered the traditional strategy for treatment which focused only on highly radical operations. The new strategy preserves patients' quality of life, while at the same time maintaining a high level of radicality, by employing a function-preserving operation which prevents post-gastrectomy syndrome. The Japanese gastric cancer treatment guidelines have standardized indications for the function-preserving surgery that is widely performed in Japan. There are various kinds of function-preserving operations, such as those reducing the extent of gastrectomy, and those providing nerve preservation, sphincter preservation, and formation of a new-stomach. Evaluation of preserved function is not satisfactory, because there is no gold standard for measuring gastrointestinal motor function and patients' quality of life.

Assessment of the preserved function of the remnant stomach in pylorus-preserving gastrectomy by gastric emptying scintigraphy

BACKGROUND

This study evaluated the preserved function of the remnant stomach by gastric emptying scintigraphy in patients who underwent pylorus-preserving gastrectomy (PPG), and it investigated whether this examination method is a useful tool for evaluation.

MATERIALS AND METHODS

The residual stomach function was evaluated by gastric emptying scintigraphy in 45 patients with early gastric cancer who had undergone PPG. Function was classified as rapid, intermediate, and delayed emptying types according to gastric emptying curves. Then, the relationships were examined between the gastric emptying types and postprandial symptoms, food intake status, body weight changes, and endoscopic findings.

RESULTS

Seventy-three percent of the PPG patients were classified as belonging to the intermediate emptying type, and the remainder to the delayed emptying type. The frequencies of complaints such as epigastric fullness, nausea, and vomiting were high in the delayed emptying-type patients. The intermediate emptying-type patients consumed larger amounts of food and gained more weight than the delayed emptying-type patients. It was difficult to estimate gastric emptying function from endoscopic findings.

CONCLUSIONS

Gastric function was evaluated by gastric emptying scintigraphy in PPG patients. This method might be useful not only for evaluating the motor function of the remnant stomach, but also for predicting postoperative status.

Duodenal interdigestive migrating motor complex in patients 5 years or more after pylorus-preserving gastrectomy for early gastric cancer

BACKGROUND

We investigated the relationship between interdigestive migrating motor complex, phase III (IMMC-pIII) and postoperative quality of life (QOL) in pylorus-preserving gastrectomy (PPG) patients.

MATERIALS AND METHODS

A total of 40 patients (26 men and 14 women; average age 59.4 years) 5 to 7.5 years after PPG for early gastric cancer (Billroth I) (average 6 years and 3 months) were divided into two groups according to the occurrence of IMMC-pIII from the duodenum, and their postoperative quality of life (QOL) was compared.

RESULTS

As for appetite, "No change compared with before operation" was significantly more frequent in the IMMC-pIII positive group compared with the negative group (P=0.0002). Food consumption per meal compared with normal; "80% or more" was significantly more frequent in the IMMC-pIII positive group than the negative group (P=0.0002). Body weight loss during 5 years after surgery; "6 kg or more" was significantly more frequent in the IMMC-pIII negative group than the positive group (P=0.0002). Early dumping symptoms did not occur in any patients of either group. Reflux esophagitis and nausea; no patients in the IMMC-pIII positive group experienced these symptoms, which was significantly different from the negative group (P=0.0018). Abdominal pain occurred but was significantly less frequent in the IMMC-pIII positive group than in the negative group (P=0.0023). Epigastric fullness occurred but was less frequent in the IMMC-pIII positive group compared with the negative group (P<0.0001). Gastric stasis of the remnant stomach was significantly more frequent in the IMMC-pIII negative group than in the positive group (P<0.0001). Gholelithiasis was significantly more frequent in the IMMC-pIII negative group than in the positive group (P=0.0119).

CONCLUSIONS

These results showed more satisfactory QOL in the IMMC-PIII positive group than in the negative group.

Concepts, rationale, and current outcomes of less invasive surgical strategies for early gastric cancer: data from a quarter-century of experience in a single institution

Previously proposed criteria of less invasive surgery for early gastric cancer (EGC) were based mainly on the pathological analyses of the resected specimens; however, preoperative and intraoperative information are also obviously essential for decision making on stage-dependent patient management. Furthermore, most indications and treatment options have not been systematically integrated or evaluated by treatment outcomes. We investigate in this report the rationality of less invasive surgery employed for EGC. Distribution analyses of positive nodes were investigated among 684 patients with primary solitary EGC (379 mucosal and 305 submucosal) who underwent curative resection between 1976 and 2000. Clinicopathological factors highlighted and analyzed included clinical (preoperative and intraoperative) and pathological (postoperative) cancer depth and nodal involvement, gross form, histological type, and maximum cancer diameter, as well as postoperative morbidity and mortality. The scope of lymphadenectomy can be reduced to a modified D1 for clinically mucosal, node-negative, nonpalpable gastric cancer, or for clinically submucosal, node-negative gastric cancer < or = 1.5 cm for intestinal type, or < or = 1.0 cm for diffuse type. Otherwise, a modified D2 lymphadenectomy is sufficient. Local resection can be recommended for clinically mucosal, node-negative gastric cancer without apparent ulceration < or = 4 cm if adjacent lymph nodes are proved cancer negative by a frozen section examination. If the gastric cancer has spread beyond the above criteria, a pylorus-preserving gastrectomy (PPG) can be recommended for tumors located in the middle or lower third of the stomach, provided the distal margin of the cancer is at least 4.5 cm from the pyloric ring. The PPG can be accompanied by a modified D1 or a modified D2 lymphadenectomy according to the respective dissection criteria. Results of these less invasive strategies showed reduced morbidity and mortality, as well as no recurrence or cancer-related deaths. These results suggest that each of our criteria for less invasive surgery for EGC is realistic, well stratified, and satisfactory.

Prognostic value of age and sex in early gastric cancer

BACKGROUND

The need for lymph node dissection in early gastric cancer (EGC) is controversial. The present study investigated the possibility of planning treatment for EGC according to age and sex rather than node status.

METHODS

Overall survival rate and cause of death were analysed according to age (5-year increments) and sex in 4231 patients with EGC. Cox proportional hazard regression analyses were used to identify the most valuable predictor.

RESULTS

In patients with EGC 5- and 10-year cancer-specific survival rates were 98.4 and 96.3 per cent respectively, whereas corresponding overall survival rates were 90.2 and 80.9 per cent. The critical age for determining prognosis was 70 years for men (chi2 = 131.34, P < 0.001) and 75 years for women (chi2 = 64.35, P < 0.001). For both sexes, the 10-year overall survival rate was less than 30 per cent in patients over 80 years old. Multivariate Cox stepwise regression analysis identified age as the most powerful prognostic indicator in EGC. The rate of death from causes unrelated to the tumour increased significantly with age, whereas that from recurrence was not affected by age.

CONCLUSION

Age is a better prognostic indicator than node status in both men and women with EGC. Age and sex should be taken into account as well as conventional clinicopathological variables related to lymph node metastases when determining appropriate therapy for EGC.

Treatment strategy of limited surgery in the treatment guidelines for gastric cancer in Japan

Surgical practice for gastric cancer in Japan is based on the Gastric Cancer Treatment Guidelines issued in 2001 by the Japanese Gastric Cancer Association. These recommendations list options for treatment of each stage of cancer, with clear distinctions between interventions recommended for routine use and those that should be confined to trial settings until further evidence for their curative potential becomes available. In this review, we discuss standard surgery, local resection, segmental resection, and pylorus-preserving gastrectomy (PPG) as examples of limited resection and describe in detail the indications for limited lymph-node dissection in cases of early-stage gastric cancer. At present, evidence does not support the conclusion that limited surgery is effective for local resection or for improving quality of life. Thus, use of limited surgery should be considered an experimental approach both in Japan and the West. We conclude that surgeons who are familiar with the criteria for selecting surgical procedures should decide on a case-by-case basis which technique is most appropriate. Choices should be made with consideration of the stage of the cancer, invasiveness of the surgical procedure, and the patient's history. For all procedures, the patient must give informed consent and the surgeons must accurately assess the success of the operation after surgery.