Function-preserving gastrectomy for gastric cancer in Japan

Sentinel Node Navigation Surgery for Early Gastric Cancer: A Narrative Review

Early gastric cancer (EGC) refers to malignant tumor lesions that are limited to the mucosa and submucosa layers, regardless of the presence of lymph node metastasis. Typically, EGC has a low rate of perigastric lymph node metastasis, and long-term survival outcomes are good after radical surgical treatment. The primary objective of surgical treatment for EGC is to achieve functional preservation while ensuring a radical cure. Sentinel node navigation surgery (SNNS) is a surgical technique used in the treatment of EGC. This approach achieves functional preservation by limiting lymph node dissection and performing restrictive gastrectomy guided by intraoperative negative sentinel node (SN) biopsy. Despite the apparent improvement in the detection rate of SN with the emergence of various tracing dyes and laparoscopic fluorescence systems, the oncological safety of SNNS remains a controversial research topic. SNNS, as a true form of stomach preservation surgery that enhances the quality of life, has become a topic of interest in the EGC field. In recent years, scholars from Japan and South Korea have conducted extensive research on the feasibility and safety of SNNS in the treatment of EGC. This article aims to provide reference choices for surgeons treating EGC by reviewing relevant research on SNNS for EGC in recent years.

The Short-Term and Long-Term Outcomes of Laparoscopy-Assisted Proximal Gastrectomy with Double-Tract Reconstruction versus Laparoscopy-Assisted Total Gastrectomy with Roux-en-Y Reconstruction for Adenocarcinoma of the Esophagogastric Junction: A Multicenter Study Based on Propensity Score Matching Analysis

Purpose

To compare the antireflux effect, long-term nutritional levels, and quality of life (QoL) between laparoscopy-assisted proximal gastrectomy with double-tract reconstruction (LPG-DTR) and laparoscopy-assisted total gastrectomy with Roux-en-Y reconstruction (LTG-RY) for adenocarcinoma of the esophagogastric junction (AEG).

Methods

This multicenter retrospective cohort study collected clinicopathological and follow-up data of AEG patients from January 2016 to January 2021 at five high-volume surgery centers. The study included patients who underwent digestive tract reconstruction with LPG-DTR or LTG-RY after tumor resection. Propensity score matching (PSM) was utilized to minimize confounding factors. The comparison after PSM included postoperative complications, reflux esophagitis, long-term nutritional levels, and QoL.

Results

A total of 151 consecutive patients underwent either LPG-DTR or LTG-RY. After PSM, 50 patients from each group were included in the analysis. The frequency of reflux esophagitis and Clavien-Dindo classification did not significantly differ between the two groups (P > 0.05). At 1 year after surgery, the LPG-DTR group showed significantly higher weight and hemoglobin levels than the LTG-RY group (P < 0.05). The overall postoperative Visick grade differed significantly between the groups (P < 0.05), but there was no significant difference in the proportion of patients with Visick≥III (P > 0.05).

Conclusion

Both LPG-DTR and LTG-RY are safe and feasible methods for digestive tract reconstruction in patients with AEG. Both methods have similar antireflux effects and postoperative QoL. However, LPG-DTR resulted in superior nutritional levels compared to LTG-RY. Therefore, LPG-DTR is considered a relatively effective method for digestive tract reconstruction in AEG patients.

Long‑term survival prognosis of function‑preserving curative gastrectomy for early gastric cancer

Segmental gastrectomy, mini-distal gastrectomy and local resection of the stomach are function-preserving curative gastrectomies (FPGs), which are used to treat gastric cancer in specialized centers. These surgical options are less invasive and can alleviate postgastrectomy symptoms more than standard gastrectomy; however, their association with prognosis remains to be fully elucidated. The present study aimed to compare the survival prognosis of patients diagnosed as node-negative by sentinel node biopsy (SNB) treated via FPG with reduced lymph node dissection with that of patients who underwent guideline gastrectomy (GL). This retrospective study was conducted between April 1999 and March 2016. The inclusion criteria were a diagnosis of gastric cancer type 0, of ≤5 cm, located in L or M areas, and pT1N0. Patients who underwent distal gastrectomy and pylorus-preserving gastrectomy were included as controls in the GL group. Among the 146 and 300 patients in the FPG and GL groups, respectively, only 1 patient in the GL group experienced recurrence. The overall survival (OS) of the FPG group was 96.6% at 5 years and 92.5% at 10 years, which was significantly higher than that of the GL group (P<0.05). In addition, the cumulative incidence of non-cancer-related deaths, especially pulmonary diseases, was lower in the FPG group than that in the GL group (P<0.05). Notably, the OS and non-cancer death rate in the FPG group remained significantly better after propensity score-matching analysis. In conclusion, for early gastric cancer located in M or L areas, patients treated via FPG guided by SNB have a better prognosis and fewer deaths caused by respiratory disease than those treated via GL. The present clinical trial was registered under the following trial registration numbers: UMIN000010154 (2013/3/4), UMIN000023828 (2016/8/29), jRCTs041180006 (2018/10/9).

Clinical strategies for securing negative proximal margin in early gastric cancer

Securing an appropriate proximal resection margin (PRM) is crucial for oncological safety in treating gastric cancer. This study investigated the clinicopathological characteristics of patients with incomplete PRM length of <2 cm in early gastric cancer. Clinicopathological data of 1,493 patients who underwent subtotal gastrectomy for early gastric cancer in 2012 to 2021 were retrospectively reviewed. Patients were divided into the PRM length of <2 cm and ≥2 cm groups based on pathological results. Univariate and multivariate analyses evaluated factors for incomplete PRM length. Factors related to patients with a relative PRM positive were also analyzed. The proportion of patients with a PRM length of <2 cm was 17.9% (267/1,493). Multivariate regression analysis revealed that age <50, preoperative endoscopic size of ≥3 cm, size discrepancy of ≥2 cm, and midbody tumor with a lesser curvature significantly contributed to the PRM length of <2 cm. Twenty-four patients had a relative PRM positive (24/1493, 1.6%). An incomplete PRM was the only risk factor for a positive relative PRM. Surgical treatment for early gastric cancer requires an accurate preoperative endoscopic tumor size and location evaluation. A more aggressive resection is recommended for patients with age <50, preoperative endoscopic size of ≥3 cm, size discrepancy of ≥2 cm, and midbody tumor with a lesser curvature.

Research progress of minimally invasive surgery for gastric cancer

Since the first laparoscopic radical surgery for early gastric cancer 30 years ago, there has been a gradual shift from "open" to "minimally invasive" surgery for gastric cancer. This transition is due to advancements in refined anatomy, enlarged field of view, faster recovery, and comparable oncological outcomes. Several high-quality clinical studies have demonstrated the safety and effectiveness of laparoscopy in the treatment of both early and locally advanced gastric cancer. The role of perioperative chemotherapy in managing locally advanced gastric cancer has been widely recognized, and there have been continuous breakthroughs in the exploration of targeted therapy and immunotherapy for perioperative treatment. Additionally, the application of indocyanine green near-infrared imaging technology, 3D laparoscopic technology, and robotic surgery systems has further improved the accuracy and minimally invasive nature of gastric cancer surgeries. Looking ahead, the field of minimally invasive surgery for gastric cancer is expected to become more standardized, resulting in a significant enhancement in the quality of life for gastric cancer patients.

The clinical outcomes of laparoscopic proximal gastrectomy with double-tract reconstruction versus tube-like stomach reconstruction in patients with adenocarcinoma of the esophagogastric junction based on propensity score-matching: a multicenter cohort study

Purpose

Laparoscopic proximal gastrectomy with double-tract reconstruction (LPG-DTR) and laparoscopic proximal gastrectomy with tube-like stomach reconstruction (LPG-TLR) are both function-preserving procedures performed for treating AEG. However, there is no clinical consensus on the selection of digestive tract reconstruction after proximal gastrectomy, and the best way to reconstruct the digestive tract remains controversial. This study aimed at comparing the clinical outcomes of LPG-DTR and LPG-TLR to provide some reference to the choice of AEG surgical modalities.

Methods

This was a multicenter, retrospective cohort study. we collected clinicopathological and follow-up data of patients with consecutive cases diagnosed with AEG from January 2016 to June 2021 in five medical centers. According to the way of digestive tract reconstruction after tumor resection, patients who underwent LPG-DTR or LPG-TLR were included in the present study. Propensity score matching (PSM) was performed to balance baseline variables that might affect the study outcomes. The QOL of the patients was evaluated using the Visick grade.

Results

A total of 124 eligible consecutive cases were finally included. Patients in both groups were matched using the PSM method, and 55 patients from each group were included in the analysis after PSM. There was no statistically significant difference between the two groups in terms of the operation time, amount of intraoperative blood loss, days of postoperative abdominal drainage tube placement, postoperative hospitalization days, total hospitalization cost, the total number of lymph nodes cleared, and the number of positive lymph nodes (P>0.05). There was a statistically significant difference between the two groups in terms of time to first flatus after surgery and postoperative soft food recovery time (P<0.05). For the nutritional status, the weight levels at 1 year after surgery was better in the LPG-DTR group than in the LPG-TLR group (P<0.05). There was no significant difference in Visick grade between the two groups (P>0.05).

Conclusion

The anti-reflux effect and quality of life of LPG-DTR for AEG were comparable to those of LPG-TLR. Compared with LPG-TLR, LPG-DTR provide better nutrition status for patients with AEG. LPG-DTR is a superior reconstruction method after proximal gastrectomy.

Postoperative functional evaluation of gastrectomy for gastric cancer

To improve the quality of surgical procedures for gastric cancer, it is essential to consider many components comprehensively, including gastric motility, small intestinal absorption, hormones that affect gastric motility and appetite, presence or absence of vagus nerve preservation, esophageal regurgitation on endoscopic findings, in addition to whether or not there is a physiological route for food passage through the duodenum. Furthermore, proper functional evaluation cannot be performed without considering the form and amount of energy in the nutritional supplement to be loaded, and the posture at the time of investigation. The results of functional evaluation vary according to the method selected from many available options, but we believe that use of the most physiologically accurate, appropriate and selectable option will enable us to arrive at the best resection/reconstruction technique. We have reported that it is important to consider the preservation of three elements when performing gastrectomy: 1) reduction of the extent of gastrectomy, 2) preservation of the pylorus, and 3) preservation of the vagus nerve; among which preservation of the remnant stomach is the most important. Furthermore, the selection of a reconstruction method that maintains secretion of hormones beneficial to gastric motility preserves the energy balance inherent in the human body, and also provides better quality of life.

Ingenuity and tips for laparoscopic local resection for local recurrence of early gastric cancer after endoscopic submucosal dissection: A case report

INTRODUCTION AND IMPORTANCE

The presence of severe comorbidities is associated with poor surgical outcomes in patients who undergo curative resection for gastric cancer. Herein, we present a report of laparoscopic local resection (LLR) for the local recurrence of gastric cancer in a patient with severe comorbidities.

CASE PRESENTATION

A 73-year-old man underwent endoscopic submucosal dissection (ESD) for an early gastric cancer located at the greater curvature of the gastric antrum. One year after the ESD, follow-up gastroscopy revealed a local recurrence.

CLINICAL DISCUSSION

LLR was performed owing to severe comorbidities such as chronic heart failure, severe chronic obstructive pulmonary disease, and diabetes mellitus. We confirmed the location of the tumor with an endoscope, and full-thickness stitches were placed outside the tumor to prevent displacement between the submucosal and serosal muscular layers. Full-thickness resection of the stomach wall was performed along the stitch points using an ultrasonic shear. The edge of the resection line was closed using a laparoscopic stapling system. The patient had an uneventful postoperative course and was discharged 8 days after the operation. The patient had no disease recurrence and late complications such as digestive symptom and weight loss at the 9-month follow-up after the operation.

CONCLUSION

LLR might be a suitable treatment option for high-risk patients with gastric cancer. During full-thickness resection of the stomach wall, our method enables the maintenance of a negative margin without the need for ESD.

Pathological and oncological outcomes of pylorus-preserving versus conventional distal gastrectomy in early gastric cancer: a systematic review and meta-analysis

Background

Pylorus-preserving gastrectomy (PPG) is a function-preserving surgery for the treatment of early gastric cancer (EGC) in the middle third of the stomach. According to the literature reports, PPG decreases the incidence of dumping syndrome, bile reflux, gallstone formation, and nutritional deficit compared with conventional distal gastrectomy (CDG). However, the debates about PPG have been dominated by the incomplete lymphadenectomy and oncological safety. We carried out a systematic review and meta-analysis to evaluate the pathological and oncological outcomes of PPG.

Methods

The protocol was registered in PROSPERO under number CRD42022304677. Databases including PubMed, Embase, Web of Science, and the Cochrane Register of Controlled Trials were searched before February 21, 2022. The outcomes included the pooled odds ratios (ORs) for dichotomous variables and weighted mean differences (WMDs) for continuous variables. For all outcomes, 95% confidence intervals (CIs) were calculated. Meta-analysis was performed using STATA software (Stata 14, Stata Corporation, Texas) and Review Manager 5.4.

Results

A total of 4500 patients from 16 studies were included. Compared with the CDG group, the PPG group had fewer lymph nodes harvested (WMD= −3.09; 95% CI −4.75 to −1.43; P < 0.001). Differences in the number of resected lymph nodes were observed at stations No. 5, No. 6, No. 9, and No. 11p. There were no differences in lymph node metastasis at each station. Shorter proximal resection margins (WMD = −0.554; 95% CI −0.999 to −0.108; P = 0.015) and distal resection margins (WMD = −1.569; 95% CI −3.132 to −0.007; P = 0.049) were observed in the PPG group. There were no significant differences in pathological T1a stage (OR = 0.99; 95% CI 0.80 to 1.23; P = 0.88), T1b stage (OR = 1.01; 95% CI 0.81 to 1.26; P = 0.88), N0 stage (OR = 0.97; 95% CI 0.63 to 1.48; P = 0.88), tumor size (WMD = −0.10; 95% CI −0.25 to 0.05; P = 0.187), differentiated carcinoma (OR = 1.04; 95% CI 0.74 to 1.47; P = 0.812) or signet ring cell carcinoma (OR = 1.22; 95% CI 0.90 to 1.64; P = 0.198). No significant differences were observed between the groups in terms of overall survival (HR = 0.63; 95% CI 0.24 to 1.67; P = 0.852) or recurrence-free survival (HR = 0.29; 95% CI 0.03 to 2.67; P = 0.900).

Conclusions

The meta-analysis of existing evidence demonstrated that the survival outcomes of PPG may be comparable to those of CDG. However, fewer lymph nodes at stations in No. 5, No. 6, No. 9, and No. 11p were harvested with PPG. We also found shorter proximal resection margins and distal resection margins for PPG, meaning more remnant stomachs would be preserved in PPG.

A model established using marital status and other factors from the Surveillance, Epidemiology, and End Results database for early stage gastric cancer

Currently, the postoperative prognosis of early stage gastric cancer (GC) is difficult to accurately predict. In particular, social factors are not frequently used in the prognostic assessment of early stage GC. Therefore, this study aimed to combine the clinical indicators and social factors to establish a predictive model for early stage GC based on a new scoring system. A total of 3647 patients with early stage GC from the Surveillance, Epidemiology, and End Results database were included in this study. A Kaplan-Meier survival analysis was used to compare differences in prognosis between different marital status, as an innovative prognostic indicator. Univariate and multivariate analyses were used to screen available prediction factors and then build a nomogram using the Cox proportional hazard regression model. The univariate analysis and multivariate analysis revealed that age at diagnosis, sex, histology, stage_T, surgery, tumor size, and marital status were independent prognostic factors of overall survival. Both the C-index and calibration curves confirmed that the nomogram had a great predictive effect on patient prognosis in training and testing sets. This nomogram based on clinical indicators and marital status can effectively help patients with early stage GC in the future.

Effectiveness of Intraoperative Endoscopy for Localization of Early Gastric Cancer during Laparoscopic Distal Gastrectomy

INTRODUCTION

Intraoperative localization of tumors has been considered crucial in determining adequate resection margins during laparoscopic gastrectomy for early gastric cancer (EGC). This study has evaluated the effectiveness of intraoperative endoscopy for localization of EGC during the totally laparoscopic distal gastrectomy.

METHODS

Patients with EGC who received totally laparoscopic distal gastrectomy from January 2018 to March 2020 were included in this study. Except the tumors located in the antrum, the patients were categorized into two groups: no localization procedure (n = 144) and intraoperative endoscopy (n = 65). To evaluate the effectiveness of the localization procedure, proximal resection margin (PRM) involvement by the tumor and approximation of optimal PRM were compared, including their postoperative outcomes.

RESULTS

There were 3 patients (2.1%) with tumor involvement of the PRM at the initial gastric resection in the no localization group. Distance from the tumor to the PRM was determined to be not significantly different between the no localization group and intraoperative endoscopy group. The PRM distribution pattern and reconstruction method were also not significantly different between the two groups.

DISCUSSION/CONCLUSION

Intraoperative endoscopy for localization of EGC is an effective method to avoid tumor involvement at the resection margin during the laparoscopic gastrectomy with intracorporeal gastric resection and reconstruction.

Nomograms Involving HER2 for Predicting Lymph Node Metastasis in Early Gastric Cancer

Objective: We aimed to establish a nomogram for predicting lymph node metastasis in early gastric cancer (EGC) involving human epidermal growth factor receptor 2 (HER2).

Methods: We collected clinicopathological data of patients with EGC who underwent radical gastrectomy and D2 lymphadenectomy at Ruijin Hospital, Shanghai Jiao Tong University School of Medicine between January 2012 and August 2018. Univariate and multivariate logistic regression analysis were used to examine the relationship between lymph node metastasis and clinicopathological features. A nomogram was constructed based on a multivariate prediction model. Internal validation from the training set was performed using receiver operating characteristic (ROC) and calibration plots to evaluate discrimination and calibration, respectively. External validation from the validation set was utilized to examine the external validity of the prediction model using the ROC plot. A decision curve analysis was used to evaluate the benefit of the treatment.

Results: Among 1,212 patients with EGC, 210 (17.32%) presented with lymph node metastasis. Multivariable analysis showed that age, tumor size, submucosal invasion, histological subtype, and HER2 positivity were independent risk factors for lymph node metastasis in EGC. The area under the ROC curve of the model was 0.760 (95% CI: 0.719–0.800) in the training set (n = 794) and 0.771 (95% CI: 0.714–0.828) in the validation set (n = 418). A predictive nomogram was constructed based on a multivariable prediction model. The decision curve showed that using the prediction model to guide treatment had a higher net benefit than using endoscopic submucosal dissection (ESD) absolute criteria over a range of threshold probabilities.

Conclusion: A clinical prediction model and an effective nomogram with an integrated HER2 status were used to predict EGC lymph node metastasis with better accuracy and clinical performance.

Utilization of Ultrasonic Image Characteristics Combined with Endoscopic Detection on the Basis of Artificial Intelligence Algorithm in Diagnosis of Early Upper Gastrointestinal Cancer

The aim of this study was to evaluate the diagnostic value of artificial intelligence algorithm combined with ultrasound endoscopy in early esophageal cancer and precancerous lesions by comparing the examination of conventional endoscopy and artificial intelligence algorithm combined with ultrasound endoscopy, and by comparing the real-time diagnosis of endoscopy and the ultrasonic image characteristics of artificial intelligence algorithm combined with endoscopic detection and pathological results. 120 cases were selected. According to the inclusion and exclusion criteria, 80 patients who met the criteria were selected and randomly divided into two groups: endoscopic examination combined with ultrasound imaging based on intelligent algorithm processing (cascade region-convolutional neural network (Cascade RCNN) model algorithm group) and simple use of endoscopy group (control group). This study shows that the ultrasonic image of artificial intelligence algorithm is effective, and the detection performance is better than that of endoscopic detection. The results are close to the gold standard of doctor recognition, and the detection time is greatly shortened, and the recognition time is shortened by 71 frames per second. Compared with the traditional convolutional neural network (CNN) algorithm, the accuracy and recall of image analysis and segmentation using feature pyramid network are increased. The detection rates of CNN model, Cascade RCNN model, and endoscopic detection alone in early esophageal cancer and precancerous lesions are 56.3% (45/80), 88.8% (71/80), and 44.1% (35/80), respectively. The detection rate of Cascade RCNN model and CNN model was higher than that of endoscopy alone, and the difference was statistically significant (P < 0.05). The sensitivity, specificity, positive predictive value, and negative predictive value of Cascade RCNN model were higher than those of CNN model, which was close to the gold standard for physician identification. This provided a reference basis for endoscopic ultrasound identification of early upper gastrointestinal cancer or other gastrointestinal cancers.

The evaluation of the postoperative quality of life in patients undergoing radical gastrectomy for esophagogastric junction cancer using the Postgastrectomy Syndrome Assessment Scale-45: a nationwide multi-institutional study

PURPOSE

This retrospective nationwide survey investigated the quality of life (QOL) of patients with esophagogastric junction cancer after gastrectomy using the Postgastrectomy Syndrome Assessment Scale-45.

METHODS

The Postgastrectomy Syndrome Assessment Scale-45 comprises 45 questions classified into symptoms, living status, and QOL domains. A total of 1950 gastrectomized patients with upper-third gastric or esophagogastric junction cancer returned the completed forms. Among them, 224 eligible patients with esophagogastric junction cancer were selected, including 86, 120, and 18 patients who underwent total gastrectomy, proximal gastrectomy (reconstruction-esophagogastrostomy: 56; double-tract method: 51), and other procedures, respectively.

RESULTS

The postoperative period was significantly shorter (47 ± 30 vs. 34 ± 30 months, p = 0.002), and the rates of early-stage disease and minimally invasive approaches significantly higher (both p < 0.001) in the proximal gastrectomy group than in the total gastrectomy group. Despite advantageous background factors for proximal gastrectomy, the postoperative QOL did not differ markedly between the groups. Compared to patients who underwent reconstruction with the double-tract method, patients who underwent esophagogastrostomy had significantly larger remnant stomachs but a similar QOL.

CONCLUSION

Even with total gastrectomy, a postoperative QOL comparable to that with proximal gastrectomy can be maintained. Clarifying the optimal reconstruction methods for proximal gastrectomy for esophagogastric junction cancer is warranted.

TRIAL REGISTRATION

This study was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR; registration number: 000032221).

Intraoperative Tumor Localization of Early Gastric Cancers

Recently, endoscopic screening systems have enabled the diagnosis of gastric cancer in the early stages. Early gastric cancer (EGC) is typically characterized by a shallow invasion depth and small size, which can hinder localization of EGC tumors during laparoscopic surgery. Here, we review nine recently reported tumor localization methods for the laparoscopic resection of EGCs. Preoperative dye or blood tattooing has the disadvantage of spreading. Preoperative 3-dimensional computed tomography reconstruction is not performed in real time during laparoscopic gastrectomy. Thus, they are considered to have a low accuracy. Intraoperative portable abdominal radiography and intraoperative laparoscopic ultrasonography methods can provide real-time feedback, but these methods require expertise, and it can be difficult to define the clips in some gastric regions. Despite a few limitations, intraoperative gastrofibroscopy provides real-time feedback with high accuracy. The detection system using an endoscopic magnetic marking clip, fluorescent clip, and radio-frequency identification detection system clip is considered highly accurate and provides real-time feedback; we expect a commercial version of this setup to be available in the near future. However, there is not yet an easy method for accurate real-time detection. We hope that improved devices will soon be developed and used in clinical settings.

Assessment of Lymph Node Metastasis in Patients With Gastric Cancer to Identify Those Suitable for Middle Segmental Gastrectomy

IMPORTANCE

Segmental gastrectomy, a type of function-preserving surgery, is not broadly studied but can improve postoperative function and quality of life among patients with gastric cancer (GC).

OBJECTIVE

To establish an indication for middle segmental gastrectomy (MSG) as a treatment for middle-body (MB) and high-body (HB) GC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study analyzed patients with GC undergoing surgery between January 2000 and December 2015 in the National Cancer Center, Goyang, Korea, a high-volume cancer center with a structured database and accurate long-term follow-up. Inclusion criteria were age 18 to 85 year, histologically proven adenocarcinoma located in the HB or MB, cT1 to cT3 category cancers, curative resection with negative margins performed, and follow-up for at least 3 years. Exclusion criteria were Borrmann type 4 GC, T4 category cancer, neoadjuvant chemotherapy, and a history of other cancers. Data analysis was performed from December 2018 to May 2020.

EXPOSURES

Total or subtotal gastrectomy and LN dissection.

MAIN OUTCOME AND MEASURES

The primary outcome was the rate of metastasis at LN stations 2, 4sa, 5, 6, and 11d, which cannot be dissected during MSG.

RESULTS

Among 9952 patients who underwent surgery for GC, 8219 underwent either laparoscopic or open total or subtotal gastrectomy. Seven hundred seventy-three patients (mean [SD] age, 56.21 [12.16] years; 464 men [60.0%]) had GC in the MB or HB of the stomach. Among the 701 patients included in the final analysis after exclusion of the cN2/N3 carcinomas, the mean (SD) age was 56.35 (12.24) years, and 418 (59.6%) were men. The incidence of LN metastasis was 0% at station 5 for cT1-3N0/1M0 cancers, station 4sa for cT1-2N0/1M0 cancers, station 2 for cT1N0/1M0 cancers, station 6 for cT1N1M0 cancers, station 11d for cT1N1M0-cT2N0/1M0 cancers, and station 12a for cT1N0/1M0-T2N1M0 cancers, regardless of size and differentiation. The rates of LN metastasis for cT1N0M0 cancers were 0.3% (1 of 396 LNs) at station 6 and 0.8% (1 of 129 LNs) at station 11d. Tumors 4 cm or smaller were associated with a lower risk of LN metastasis compared with tumors 4.1 cm or larger (odds ratio, 2.10; 95% CI, 1.20-3.67; P = .009), and well-differentiated tumors were associated with lower risk of LN metastasis compared with poorly differentiated tumors (odds ratio, 2.88; 95% CI, 1.45-5.73; P = .002).

CONCLUSIONS AND RELEVANCE

These findings suggest that MSG with dissection of stations 1, 3, 4sb, 4d, 7, 8a, 9, 11p, and 12a could be done for HB and MB cT1N0/1M0 gastric cancers 4 cm or smaller and well-differentiated cT2N0/1M0 cancers.

Preventive procedure for stenosis after esophagojejunostomy using a circular stapler and transorally inserted anvil (OrVil™) following laparoscopic proximal gastrectomy and total gastrectomy involving reduction of anastomotic tension

Background

Recently, due to increasing reports of stenosis after esophagojejunostomy created using circular staplers and a transorally inserted anvil (OrVil™) following laparoscopic proximal gastrectomy (LPG) and total gastrectomy (LTG), linear staplers are being used instead. We investigated our preventive procedure for esophagojejunostomy stenosis following use of circular staplers.

Methods

Since the anastomotic stenosis is considered to be mainly caused by tension in the esophageal and jejunal stumps at the anastomotic site, we have been performing procedures to relieve this tension, by cutting off the rubber band and pushing the shaft of the circular stapler toward the esophageal side, since July 2015. We retrospectively compared the incidence of anastomotic stenosis in cases of LPG and LTG performed before July 2015 (early phase, 30 cases) versus those performed after this period (later phase, 22 cases).

Results

Comparison of the incidence of anastomotic stenosis according to the type of surgery, LPG or LTG, and between the two time periods versus all cases, indicated a significantly lower incidence in the later phase than in the early phase (4.5 vs. 26.7%, p < 0.05), especially for LPG (0 vs. 38.5%, p < 0.05).

Conclusions

It is possible to use a circular stapler during laparoscopic esophagojejunostomy, as with open surgery, if steps to reduce tension on the anastomotic site are undertaken. These procedures will contribute to the spread of safe and simple laparoscopic anastomotic techniques.

Advances in the surgical management of gastric and gastroesophageal junction cancer

Since Theodore Billroth and Cesar Roux perfected the methods of post-gastrectomy reconstruction in the late 19^th century, surgical management of gastric and gastroesophageal cancer has made incremental progress. The majority of patients with localized disease are treated with perioperative combination chemotherapy or neoadjuvant chemoradiation. Staging laparoscopy before initiation of treatment or before surgical resection has improved staging accuracy and can drastically inform treatment decisions. The longstanding and contentious debate on the optimal extent of lymph node dissection for gastric cancer appears to have settled in favor of D2 dissection with the recently published 15-year follow-up of the Dutch randomized trial. Minimally invasive gastric and gastroesophageal resections are performed routinely in most centers affording faster recovery and equivalent oncologic outcomes. Pylorus-preserving distal (central) gastrectomy has emerged as a less invasive, function-preserving option for T1N0 middle-third gastric cancers, while randomized data on its oncologic adequacy are pending. Multi-visceral resections and cytoreductive surgery with hyperthermic intraperitoneal chemotherapy has been utilized selectively for patients with locally advanced tumors who have demonstrated disease control on preoperative chemotherapy. This review summarizes the current standard of surgical care for gastroesophageal junction and gastric cancer as well as highlights recent and upcoming advances to the field.

Preservation of hepatic branch of the vagus nerve reduces the risk of gallstone formation after gastrectomy

BACKGROUND

Injury to the vagus nerve has been proposed to be associated with occurrence of gallstones after gastrectomy. We investigated the effect of preservation of hepatic branch of the vagus nerve on prevention of gallstones during laparoscopic distal (LDG) and pylorus-preserving gastrectomy (LPPG).

METHODS

Preservation of the vagus nerve was reviewed of cT1N0M0 gastric cancer patients underwent LDG (n = 323) and LPPG (n = 144) during 2016-2017. Presence of gallstones was evaluated by ultrasonography (US) and computed tomography (CT). Incidences of gallstones were compared between the nerve preserved (h-DG, h-PPG) group and sacrificed (s-DG, s-PPG) group. Clinicopathological features were also compared.

RESULTS

The 3-year cumulative incidence of gallstones was lower in the h-DG (2.7%, n = 85) than the s-DG (14.6%, n = 238) (p = 0.017) and lower in the h-PPG (1.6%, n = 123) than the s-PPG (12.9%, n = 21) (p = 0.004). Overall postoperative complication rate was similar between the h-DG and s-DG (p = 0.861) as well as between the h-PPG and s-PPG (p = 0.768). The number of retrieved lymph nodes station #1 and 3-year recurrence-free survival were not significantly different between the preserved group and sacrificed group. Injury to the vagus nerve (p = 0.001) and high body mass index (BMI) (≥ 27.5 kg/m²) (p = 0.040) were found to be independent risk factors of gallstone formation in multivariate analysis.

CONCLUSIONS

Preservation of hepatic branch of the vagus nerve can be recommended for LDG as well as LPPG of early gastric cancer patients to reduce postoperative gallstone formation.

Current status of proximal gastrectomy for gastric and esophagogastric junctional cancer: A review

Proximal gastrectomy (PG) is one of the function-preserving surgical methods for the treatment of upper gastric cancer. Favorable postoperative results have been reported in comparison with total gastrectomy. However, because there are challenges, such as postoperative reflux esophagitis, anastomotic stenosis, and residual food, appropriate selection of a reconstruction method is crucial. Some methods include esophagogastric anastomosis, including simple esophagogastrostomy, tube-like stomach esophagogastrostomy, side overlap with fundoplication by Yamashita, and double-flap technique, and reconstruction using the small intestine, including double-tract methods, jejunal interposition, and jejunal pouch interposition. However, standard reconstruction methods are yet to be established. PG has also been employed in early gastric cancer of the upper third of the stomach, and indications have also been extended to esophagogastric junction cancer, which has shown an increase in recent years. Although many retrospective studies have revealed the functional benefits or oncological safety of PG, the characteristics of each surgical procedure should be understood so that an appropriate reconstruction method, with a reflux prevention mechanism and minimal postoperative injury, can be selected.

Feasibility of totally laparoscopic pylorus-preserving gastrectomy with intracorporeal gastro-gastrostomy for early gastric cancer: a retrospective cohort study

Background

Pylorus-preserving gastrectomy (PPG) has been accepted as a function-preserving surgery for the treatment of early gastric cancer in East Asian countries. Therefore, this study aimed to evaluate the feasibility and safety of totally laparoscopic PPG (TLPPG) with intracorporeal anastomosis.

Methods

A total of 43 patients with early gastric cancer underwent laparoscopy-assisted PPG (LAPPG) with extracorporeal anastomosis between May 2006 and November 2012. The operative outcomes of 22 patients who underwent TLPPG between November 2012 and February 2019 were evaluated, and data were compared with that of the LAPPG group.

Results

No significant difference in the operative time was observed between the two groups. Blood loss was lower in the TLPPG group (18.5 mL) than in the LAPPG group (30.7 mL, p = 0.008), and the length of abdominal incision was shorter in the TLPPG group (3.8 cm) than in the LAPPG group (4.7 cm, p < 0.001). No significant difference in the complication rate was observed between the two groups (13.6% in the TLPPG vs. 9.3% in the LAPPG group, p = 0.594). No anastomosis-related complications occurred in either group. No significant between-group difference was observed in the delayed gastric emptying (TLPPG, 9.1 vs. LAPPG, 7%, p = 0.762). The initiation of postoperative fluid (TLPPG, 1.0 day vs. LAPPG, 3.0 days, p < 0.001) and meal (TLPPG, 3.0 days vs. LAPPG, 4.0 days, p < 0.001) intake was earlier in the TLPPG group than in the LAPPG group. No significant between-group difference was observed in the postoperative hospital stay.

Conclusions

The findings of this study suggest that TLPPG with intracorporeal reconstruction not only is as feasible and safe as LAPPG for the treatment of patients with early gastric cancer but also provides certain advantages such as reduced blood loss and wound size.

Integrating tumor and nodal radiomics to predict lymph node metastasis in gastric cancer

BACKGROUND

To develop and validate a radiomics method via integrating tumor and lymph node radiomics for the preoperative prediction of lymph node (LN) status in gastric cancer (GC).

MATERIALS AND METHODS

We retrospectively collected 170 contrast-enhanced abdominal CT images from GC patients. Five times repeated random hold-out experiment was employed. Tumor and nodal radiomics features were extracted from each individual tumor and LN respectively, and then multi-step feature selection was performed. The optimal tumor and nodal features were selected using Pearson correlation analysis and sequential forward floating selection (SFFS) algorithm. After feature fusion, the SFFS algorithm was used to develop radiomics signatures. The performance of the radiomics signatures developed based on logistic regression classifier was further analyzed and compared using the area under the receiver operating characteristic curve (AUC).

RESULTS

The AUC values, reported as mean ± standard deviation, were 0.9319 ± 0.0129 and 0.8546 ± 0.0261 for the training and validation cohorts respectively. The radiomic signatures could predict LN status, especially in T2-stage, diffuse-type and moderately/well differentiated GC. After integrating clinicopathologic information, the radiomic-clinicopathologic model (training cohort, 0.9432 ± 0.0129; validation cohort, 0.8764 ± 0.0322) showed a better discrimination capability than other radiomics models and clinicopathologic model. The radiomic-clinicopathologic model also showed superior performance to the gastroenterologist' decision in all experiments, and outperformed the radiologist in some experiments.

CONCLUSION

Our proposed method presented good predictive performance and great potential for predicting LNM in GC. As a noninvasive preoperative prediction tool, it can be helpful for guiding the prognosis and treatment decision-making in GC patients.

Knockdown of ST7-AS1 inhibits migration, invasion, cell cycle progression and induces apoptosis of gastric cancer

Role of ST7-AS1 in the malignant progression of gastric cancer (GC) and its molecular mechanisms were investigated. ST7-AS1 level in GC tissues and matched normal tissues was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Its level in GC patients presenting different tumor stages and tumor sizes was determined. Subsequently, ST7-AS1 level in epithelial cells of gastric mucosa and GC cell lines was examined. Cellular behavior of GC cells, including viability, apoptosis, migration, invasion and cell cycle, influenced by ST7-AS1 was evaluated. The interaction between ST7-AS1 and EZH2 was assessed by RNA immunoprecipitation (RIP) assay. The involvement of EZH2 in the progression of GC mediated by ST7-AS1 was identified. ST7-AS1 was upregulated in GC tissues and cell lines. Its level was positively correlated to tumor stage and tumor size of GC. Knockdown of ST7-AS1 attenuated proliferative, migratory and invasive abilities, arrested cell cycle progression and induced apoptosis of GC cells. EZH2 was identified to interact with ST7-AS1, which attenuated the regulatory effects of ST7-AS1 on migratory and invasive abilities of GC cells. Upregulated ST7-AS1 in GC accelerated proliferation, migration and invasion, and inhibited apoptosis, thus aggravating the progression of GC.

Pylorus-preserving gastrectomy for early cancer involving the upper third: can we go higher?

BACKGROUND

Pylorus-preserving gastrectomy (PPG) is commonly performed for early gastric cancer (EGC) located in middle third of the stomach. We investigated the surgical, oncological, and functional outcomes of PPG involving the upper third of stomach.

METHODS

We included all patients of the period 2013-2016 who underwent PPG, distal subtotal gastrectomy (DSG), and total gastrectomy (TG) for EGC involving the upper third by carefully defining the localization. Surgical, oncological, and functional outcome analyses included postoperative morbidity, lymph-node metastasis, tumor recurrence, postoperative body weight, body mass index, hemoglobin, total protein, albumin, quantification of intraabdominal fat, and gallstone development.

RESULTS

Overall, 288 cases were analyzed: 145 PPG, 61 DSG, and 82 TG. In the study period, patients potentially underwent PPG for EGC involving the upper third, if enough proximal remnant stomach was found whilst achieving a sufficient proximal margin. PPG resulted in less operation time (p < 0.001), less blood loss (p = 0.002) and lower postoperative morbidity compared to TG. For lymph-node (LN) stations being resected in all groups, no difference was found in number of resected LN. Recurrence-free survival was similar for all groups. PPG showed advantages regarding postoperative body weight, hemoglobin, total protein, albumin in postoperative 6 and 12 month follow-up. Lowest decrease of abdominal fat area after 12 months was seen for PPG. Gallstone incidence was significantly lower after PPG compared to TG (p < 0.001).

CONCLUSIONS

For EGC involving the upper third, PPG can be another good option with lower postoperative morbidity, better functional outcomes, and same oncological safety.

What Is the Best Operation for Proximal Gastric Cancer and Distal Esophageal Cancer?

Cancer of the gastroesophageal junction (GEJ) is increasing in incidence, likely as a result of rising obesity and gastroesophageal reflux disease rates. The tumors that arise here share features of esophageal and gastric cancer, and are classified based on their location in relationship to the GEJ. The definition of the GEJ itself, as well as optimal resection strategy, extent of lymph node dissection, resection margin length, and reconstruction methods are still very much a subject of debate. This article summarizes the available evidence on this topic, and highlights specific areas for further research.

Can proximal Gastrectomy Be Justified for Advanced Adenocarcinoma of the Esophagogastric Junction?

Purpose

To evaluate the status of number 3b lymph node (LN) station in patients with adenocarcinoma of the esophagogastric junction (AEG) and to investigate the optimal indications for radical proximal gastrectomy (PG) for AEG.

Materials and Methods

Data of 51 patients with clinically advanced Siewert types II and III AEG who underwent total gastrectomy (TG) between April 2010 and July 2017 were reviewed. The proportion of metastatic LNs at each LN station was examined. Number 3 LN station was separately classified into number 3a and number 3b. The risk factors for number 3b LN metastasis and the clinicopathological features of number 3b-positive AEG patients were investigated.

Results

The incidences of LN metastasis were the highest in number 1 (47.1%), followed by number 2 (23.5%), number 3a (39.2%), and number 7 (23.5%) LN stations. LN metastasis in number 3b LN station was detected in 4 patients (7.8%). A gastric invasion length of more than 40 mm was a significant risk factor for number 3b LN metastasis. All 4 patients with number 3b-positive AEG had advanced cancer with a gastric invasion length of more than 40 mm. The 5-year survival rate of patients with a gastric invasion length of more than 40 mm was 50.0%.

Conclusions

Radical PG may be indicated for patients with AEG with gastric invasion length of less than 40 mm.

Similar hematologic and nutritional outcomes after proximal gastrectomy with double-tract reconstruction in comparison to total gastrectomy for early upper gastric cancer

BACKGROUND

Proximal gastrectomy offers theoretical benefits over total gastrectomy in terms of hematologic and nutritional outcomes. However, little evidence confirming these benefits has been reported. The aim of this study was to assess the hematologic and nutritional outcomes of proximal gastrectomy with double-tract reconstruction in comparison to those of total gastrectomy.

METHODS

We retrospectively analyzed data from 80 patients with stage I gastric cancer who underwent proximal gastrectomy with double-tract reconstruction (n = 38) or total gastrectomy (n = 42) from September 2014 to December 2015. We compared hematologic (including hemoglobin, ferritin, vitamin B₁₂, etc.) and nutritional outcomes [including body mass index (BMI), serum total protein, albumin, total cholesterol, and total lymphocyte count] between the two groups.

RESULTS

We found no significant differences in changes in hemoglobin (P = 0.250) or cumulative incidence of iron deficiency anemia (P = 0.971) during a median follow-up period of 24 months (range 18-30 months) after surgery. Cumulative incidence of vitamin B₁₂ deficiency also did not differ significantly between the proximal and total gastrectomy groups (P = 0.087). BMI changes from baseline were not significantly different between the two groups (P = 0.591). Likewise, there were no statistically significant differences in nutritional outcomes.

CONCLUSIONS

Proximal gastrectomy with double-tract reconstruction exhibited similar outcomes in terms of hematologic and nutritional features in comparison to total gastrectomy.

Functional evaluations comparing the double-tract method and the jejunal interposition method following laparoscopic proximal gastrectomy for gastric cancer: an investigation including laparoscopic total gastrectomy

Purpose

Functional outcomes were prospectively compared between two types of reconstruction [double tract (L-DT; n = 15) and jejunal interposition (L-JIP; n = 15)] following laparoscopic half-proximal gastrectomy (LPG), including laparoscopic total gastrectomy (L-TG; n = 30) as a control group, at 1 year after surgery.

Methods

Clinical investigations were performed in each patient, and functional evaluations, involving the swallowing of an alimentary liquid containing acetaminophen (AAP), followed by measurements of the concentrations of AAP and hormones in the sitting (n = 5) and in the supine positions (n = 5), were carried out in each group.

Results

The post-/preoperative body weight ratios were significantly higher in the L-DT and L-JIP groups than in the L-TG group. The AAP levels were significantly lower in the LPG group than in the LTG group. The AAP, insulin, and gastrin levels in the L-JIP group were markedly increased in the sitting position compared with the supine position, while those in the L-DT and L-TG groups were stable in both positions.

Conclusions

L-JIP and L-DT are procedures that maintain gradual intestinal absorption and help improve the quality of life. Intestinal absorption and hormonal secretion were relatively unaffected by the posture of the meal intake after L-DT, so L-DT might be the procedure providing the most stable results.

The benefits of targeted endoscopic biopsy performed using the autofluorescence based diagnostic technique in 67 cases of diagnostically difficult gastrointestinal tumors

INTRODUCTION

The search for new diagnostic and therapeutic procedures is an essential task in contemporary oncology. The purpose of our study was the evaluation of the practical usefulness of autofluorescence endoscopy (AFE) using the Onco-LIFE system, compared with the use of white light endoscopy (WLE), and the estimation of the correlation between the histopathological evaluation with the degree of lesions' Numerical Color Value (NCV index) and the method's sensitivity and specificity valuation.

MATERIAL

67 patients were analyzed at the Center for Laser Diagnostics and Therapy. All patients previously had a gastrointestinal tract tumor, which appeared malignant, but without histopathological confirmation. We measured NCV, estimated the correlation of the clinical diagnosis based on histopathological evaluation with the degree of NCV index from gastrointestinal lesions, and calculated the sensitivity and specificity of this method.

RESULTS

In the group of 67 patients, we found 44 cases of primary or secondary cancers and 7 cases of non-epithelial malignancies. In this group (51 patients) we identified 13 colorectal cancers and 38 upper gastrointestinal cancers. Based on the NCV index at NCV > 1.0, we revealed, that the sensitivity for malignant neoplastic lesions was 100% and the specificity was 73%, while for NCV > 1.5, the sensitivity for malignant neoplastic lesions was 86% and the specificity 100%.

CONCLUSION

AFE using the Onco-LIFE system is a helpful tool to perform targeted biopsies at the outset. A significant correlation was found between lesions' NCV index and the grade of dysplasia or tumor malignancy. AFE sensitivity and specificity is higher than WLE. Further studies are needed, especially performed by expert endoscopists.

Function-preserving surgery for gastric cancer: current status and future perspectives

The number of early gastric cancer (EGC) cases has been increasing because of improved diagnostic procedures including endoscopy and screening systems. Therefore, function-preserving gastrectomy (FPG) for EGC with the expectation of better quality of life (QOL) after surgery may be increasingly utilized, due to its association with low rate of lymph node metastasis and excellent survival and the possibility of employing less invasive procedures such as laparoscopic gastrectomy in combination. Pylorus-preserving gastrectomy (PPG) with curative intent lymph node dissection is a representative FPG that has been used in EGC, and its superiorities, indications, limitations, and survival benefits have already been reported in several retrospective studies. Laparoscopic proximal gastrectomy (LAPG) has also been employed in EGC of the upper third of the stomach; however, LAPG was found to be associated with major issues in achieving a balance between swallowing and reflux prevention. In patients with EGC in the upper third of the stomach, laparoscopy-assisted subtotal gastrectomy with a preserved, albeit very small, stomach may provide a better QOL and fewer postoperative complications. FPG is recommended as a surgical treatment for EGC if the indication is accurately diagnosed and strictly confirmed; however, these techniques in laparoscopic surgery present technical difficulties to surgeons without a certain degree of skills. Although many retrospective studies revealed the functional benefits or oncological safety with FPG, further prospective studies using large case series are necessary to reveal the value of FPG compared with the conventional procedures.

MiR-451 as a new tumor marker for gastric cancer

Gastric cancer is the second most common malignancy in China. However, the prognosis for gastric cancer patients remains poor. The purpose of this study was to investigate whether miR-451 was a potential prognostic biomarker for gastric cancer. Fresh tissues were immediately frozen in liquid nitrogen until use. The plasma was extracted and quantitative real-time polymerase chain reaction was performed to detect miR-451 expression. The Student's t test analysis and multivariate Cox regression analysis were performed to analyze expression of miR-451. The analysis results showed that the expression level of miR-451 was decreased expression in gastric cancer tissue. The down-regulation of miR-451 tended to be positively correlated with tumor stage, lymphatic metastasis and shorter overall survival of patients. MiR-451 may be a potential biomarker and a potential therapeutic target for the diagnoses and prognosis of gastric cancer.