Short-term outcomes of multicenter prospective cohort study of gastric endoscopic resection: 'Real-world evidence' in Japan

Protective effect of proton pump inhibitors and potassium competitive acid blockers against post-gastric endoscopic submucosal dissection bleeding: a single-center, propensity score-matched analysis

OBJECTIVES

Both potassium-competitive acid blockers (P-CABs) and proton pump inhibitors (PPIs) are known to be protective against bleeding after gastric endoscopic dissection (ESD) for early gastric cancers. The aim was to compare the effect of PPI and P-CAB treatment against bleeding after gastric ESD.

MATERIALS AND METHODS

This was a single-center, retrospective analysis. Among 541 patients who underwent gastric ESD during the period from 2014 to 2019, we recruited subjects who were treated with PPIs (intravenous lansoprazole followed by oral esomeprazole) or a P-CAB before and after ESD. The incidence of post-ESD bleeding was compared between treatment groups. The risks associated with post-ESD bleeding were examined by univariate and multivariate analyses after propensity score-matching.

RESULTS

The overall incidence of post-ESD bleeding was not significantly different between patients treated with PPIs (n = 362) and those treated with a P-CAB (n = 156) (3.0% vs 2.6%, respectively; p = .77). Even after propensity score matching (n = 153 in each group), the incidence was not significantly different between groups (2.6% vs 2.6%, respectively; p = 1.00). A multivariate analysis revealed that antithrombotic therapy (OR 4.85, 95% CI 1.14-20.57) was an independent factor associated with post-ESD bleeding.

CONCLUSIONS

The incidence of post gastric ESD bleeding is not different between patients treated with PPI and patients treated with P-CAB. Antithrombotic therapy is an independent risk factor associated with post-ESD bleeding.

Current status and future perspective of artificial intelligence applications in endoscopic diagnosis and management of gastric cancer

Image recognition using artificial intelligence (AI) has progressed significantly due to innovative technologies such as machine learning and deep learning. In the field of gastric cancer (GC) management, research on AI-based diagnosis such as anatomical classification of endoscopic images, diagnosis of Helicobacter pylori infection, and detection and qualitative diagnosis of GC is being conducted, and an accuracy equivalent to that of physicians has been reported. It is expected that AI will soon be introduced in the field of endoscopic diagnosis and management of gastric cancer as a supportive tool for physicians, thus improving the quality of medical care.

Guidelines for endoscopic submucosal dissection and endoscopic mucosal resection for early gastric cancer (second edition)

In response to the rapid and wide acceptance and use of endoscopic treatments for early gastric cancer, the Japan Gastroenterological Endoscopy Society, in collaboration with the Japanese Gastric Cancer Association, produced "Guidelines for Endoscopic Submucosal Dissection and Endoscopic Mucosal Resection for Early Gastric Cancer" in 2014, as a set of basic guidelines in accordance with the principles of evidence-based medicine. At the time, a number of statements had to be established by consensus (the lowest evidence level), as evidence levels remained low for many specific areas in this field. However, in recent years, the number of well-designed clinical studies has been increasing. Based on new findings, we have issued the revised second edition of the above guidelines that cover the present state of knowledge. These guidelines are divided into the following seven categories: indications, preoperative diagnosis, techniques, evaluation of curability, complications, long-term postoperative surveillance, and histology.

Management following endoscopic resection in elderly patients with early-stage upper gastrointestinal neoplasia

With the ongoing increase in the aging population in Japan, the number of elderly patients among the total population with upper gastrointestinal (GI) neoplasia has also been increasing. As elderly patients present unique age-related variations in their physical condition, the therapeutic approach for upper GI neoplasia should be differentiated between elderly and nonelderly patients. According to the existing guidelines, additional treatment is the standard therapy in patients who undergo endoscopic resection (ER) with a possible risk of lymph node metastasis (LNM) for upper GI neoplasia. However, due to the relatively low rate of LNM, applying additional treatment in all elderly patients may be excessive. Although additional treatment has the advantage of reducing cancer-specific mortality, its disadvantages include deteriorated quality of life, complications, and mortality in surgery. In patients with early gastric cancer, we propose treatment decisions be made using a risk-scoring system for LNM and upon considering the physical condition of the patient after ER with curability C-2. In those with superficial esophageal squamous cell carcinoma with a possible risk of LNM after ER, selective chemoradiotherapy may be a less-invasive treatment option, although the present standard treatment is esophagectomy. When considering the treatment decision, achieving a "cure" of the tumor has been regarded as critical. However, as the main cause of mortality in elderly patients with ER for upper GI neoplasia is noncancer-related death, both achieving a "cure" and also a good level of "care" is important in the management of elderly patients.

Clinical Characteristics of Intramucosal Gastric Cancers with Lymphovascular Invasion Resected by Endoscopic Submucosal Dissection

INTRODUCTION

In patients with intramucosal gastric cancer (MGC) who have undergone endoscopic submucosal dissection (ESD), lymphovascular invasions (LVIs) such as lymphatic invasion or venous invasion are considered risk factors of lymph node metastasis (LNM). However, the rate of LNM in MGCs with LVI and their clinicopathological features are unclear.

OBJECTIVE

This study aimed to examine the rate of LNM and clinical characteristics of MGCs with LVI as compared to MGCs without LVI and minimally invasive submucosal gastric cancers (mSMGCs) with LVI.

METHODS

Among the early gastric cancers excluding the remnant stomach who underwent ESD at our hospital from July 2003 to September 2018, the MGCs with LVI were included as the target in this study. MGCs without LVI and mSMGCs with LVI were also included as control.

RESULTS

Seventeen lesions in 17 patients with MGCs with LVI, 1,149 lesions in 865 patients with MGCs without LVI, and 29 lesions in 29 patients with mSMGCs with LVI were analyzed. LVI was noted in 1.5% (17/1,166) of MGC cases. During follow-up of the MGC cases with LVI, there were no LNM or recurrences reported, and 14 patients survived and 3 died of other diseases. However, LNM occurred in 2 cases of mSMGC. Among the MGC cases, univariate analysis showed that the pap component, elevated type, and tumor diameters of 20 mm or more were statistically significant factors with respect to LVI, while multivariate analysis showed that the pap component was the only significant factor.

CONCLUSION

Careful follow-up may be appropriate for MGCs with LVI due to the low risk of LNM. Additionally, the pap component is a significant factor in MGCs with LVI.

Reduction in the procedure time of hybrid endoscopic submucosal dissection for early gastric neoplasms: a multi-center retrospective propensity score-matched analysis

BACKGROUND

Endoscopic submucosal dissection (ESD) for early gastric neoplasms is still a technically difficult and time-consuming procedure. Hybrid ESD (H-ESD) involves circumferential incision with partial submucosal dissection combined with subsequent mucosal resection by snaring, wherein the newly developed device allows us to perform H-ESD using a single device. This study aimed to determine the clinical outcomes of H-ESD compared with conventional ESD (C-ESD) for early gastric neoplasms.

METHODS

In this multi-center, retrospective study, using propensity score-matched analysis, we reviewed the charts of patients with early gastric neoplasms smaller than 20 mm treated with H-ESD or C-ESD at three hospitals between January 2017 and October 2018. The primary outcome was the procedure time, and the secondary outcomes were other factors, including the en bloc resection rate, complete resection rate, curative resection rate, and rate of adverse events.

RESULTS

Among 215 patients, 29 underwent H-ESD and 186 underwent C-ESD; 29 pairs were created by propensity score matching. In the H-ESD group, 82.8% of lesions met the absolute indication [mucosal lesions limited to 20-mm diameter, dominated by differentiated adenocarcinoma without ulcer (scar)] for endoscopic resection (ER). As a result, the procedure time of H-ESD was significantly shorter than that of C-ESD [20 (interquartile range, 12-27) min versus 40 (30-50) min; p < 0.001]. There was no significant difference in the secondary outcomes between the two groups.

CONCLUSION

H-ESD contributed to reduced procedure time. Therefore, H-ESD could be an alternative endoscopic treatment for gastric neoplasms when the lesion fulfils the absolute indication for ER.

Prevalence and risk factors for lymph node metastasis after noncurative endoscopic resection for early gastric cancer: a systematic review and meta-analysis

BACKGROUND

Additional surgery for all patients with noncurative resection after endoscopic resection (ER) for early gastric cancer (EGC) may be excessive due to the relatively low rate of lymph node metastasis (LNM) in such patients. However, the prevalence and risk factors for LNM after noncurative ER have not been consistent across studies.

METHODS

We performed a systematic review of electronic databases through August 10, 2018 to identify cohort studies with patients who underwent additional surgery after noncurative ER for EGC. The prevalence of LNM in such patients was extracted for all studies. Odds ratios (ORs) were combined using random-effects meta-analyses to assess the risk of LNM, when possible.

RESULTS

We identified 24 studies comprising 3877 patients with 311 having LNM (pooled prevalence, 8.1%). The risk of LNM was significantly increased in lymphatic invasion (OR [95% confidence interval] = 4.22 [2.88-6.19]), lymphovascular invasion (LVI) (4.17 [2.90-5.99]), vascular invasion (2.38 [1.65-3.44]), positive vertical margin (2.16 [1.59-2.93]), submucosal invasion depth of ≥ 500 μm (2.14 [1.48-3.09]), and tumor size > 30 mm (1.77 [1.31-2.40]). In contrast, there was no significant association between undifferentiated-type or ulceration (scar) and LNM. When studies were restricted to those that evaluated the adjusted OR, the risk of vascular invasion for LNM did not reach statistical significance.

CONCLUSIONS

Several pathological factors, most notably lymphatic invasion and LVI, were associated with LNM in patients with noncurative resection after ER for EGC. Lymphatic and vascular invasion should be assessed separately instead of LVI (PROSPERO CRD42018109996).

A Recent Argument for the Use of Endoscopic Submucosal Dissection for Early Gastric Cancers

Endoscopic submucosal dissection (ESD) has become the standard treatment method for early gastric cancers (EGCs) due to the negligible risk for lymph node metastasis (LNM) in Eastern Asian countries. According to the guidelines, the curability of EGC after endoscopic resection was classified into three groups: curative resection, expanded curative resection, and noncurative resection. In Eastern Asian countries, a structured follow-up schedule is needed for patients undergoing curative resection and expanded curative resection. Conversely, in Western countries, additional surgery may be recommended for some patients undergoing expanded curative resection (ulcerated, undifferentiated, or slight submucosal invasion) due to the potential risk for LNM, even though specimens of ESD and surgery may not be handled with the same methodology as that used in Japan, which may lead to this slightly higher risk. In noncurative resection, additional surgery is the standard method after ESD because of the risk for LNM. However, in elderly patients and/or those with severe underlying diseases, the advantages and disadvantages of additional surgery should be considered when selecting a post-ESD treatment strategy for patients undergoing noncurative resection. Risk-scoring systems for LNM may facilitate clinical decisions for these patients. However, it should be noted that when recurrence was detected in patients who were followed up with no additional treatment after ESD with noncurative resection, most of them had a poor prognosis. To select an appropriate treatment method, especially in elderly patients undergoing ESD with noncurative resection, a new tool for evaluating the condition of patients should be established.

Current evidence and issues of endoscopic submucosal dissection for gastric neoplasms during antithrombotic therapy

Endoscopic submucosal dissection (ESD) for gastric neoplasms is a useful treatment globally. However, postoperative bleeding after gastric ESD is a serious, and sometimes life-threatening complication in patients receiving antithrombotic drugs, because antithrombotic drugs are considered to increase the risk of postoperative bleeding after gastric ESD. In contrast, withdrawal of antithrombotic drugs during the perioperative period increases the risk of thrombotic complications. Guidelines for the management of antithrombotic drugs during the periendoscopic period have been published by different countries, and recent guidelines place greater emphasis on the risk of thromboembolism with the discontinuation of antithrombotic drugs than on the risk of bleeding with the continuation of antithrombotic drugs. Several studies have reported on the validity of these guidelines, and clinical evidence is being established. Most studies reported that gastric ESD under continuation of aspirin or cilostazol did not increase the risk of bleeding, whereas heparin replacement was strongly associated with a higher risk of bleeding. However, the data regarding some clinical issues about the management of antithrombotic drugs, such as the safety of gastric ESD under continuation of thienopyridine, administration of multiple antithrombotic drugs including dual antiplatelet and anticoagulants (warfarin and direct oral anticoagulant), and effective prophylactic methods for postoperative bleeding after gastric ESD are lacking. Larger clinical data are needed to resolve the remaining issues in the future.

Efficacy of vonoprazan for the prevention of bleeding after gastric endoscopic submucosal dissection with continuous use of antiplatelet agents

Background  Post-procedural bleeding, after gastric endoscopic submucosal dissection (ESD) for high risk thromboembolic cases that require continuous antiplatelet therapy, is challenging. Its incidence rate is > 20 % among those using conventional antacids. We evaluated the efficacy of perioperative management with vonoprazan to prevent post-ESD bleeding. Materials and methods  This was a multicenter prospective interventional trial conducted at 10 Japanese referral centers. Patients who regularly used antiplatelet agents (aspirin or thienopyridine derivatives, etc.) and who required continuous antithrombotic medication due to high thromboembolic risk were enrolled. They underwent gastric ESD with continuous aspirin therapy. Oral administration of vonoprazan (20 mg daily) was started from the day of ESD and continued for 28 days. The primary end point was the incidence of post-ESD bleeding. The sample size was 50 patients, and vonoprazan was considered to be effective when the upper threshold of the 95 % confidence interval (CI) for post-ESD bleeding did not exceed 20 %. Results  Although 50 patients were enrolled, one patient withdrew consent. Therefore, 49 patients were included in the analysis. One patient who used aspirin and clopidogrel experienced bleeding 11 days after ESD. The overall post-ESD bleeding rate was 2.0 % (1/49; 95 %CI 0.4-10.7 %). Thromboembolic events were not observed. One case of ESD-associated adverse events (perforation) and one case of drug-associated adverse events (drug eruption, possibly due to vonoprazan) were observed. Conclusions  Vonoprazan may be efficacious for preventing post-ESD bleeding in patients using continuous antiplatelet therapy, warranting further comparative study to definitively test the effectiveness of the drug.

Risk Factors for Post-gastric Endoscopic Submucosal Dissection Bleeding with a Special Emphasis on Anticoagulant Therapy

BACKGROUND

Little is known about the risk factors for post endoscopic submucosal dissection (post-ESD) bleeding with anticoagulant therapy.

AIMS

We aimed to investigate the risk factors for post-ESD bleeding for early gastric cancer (EGC) with an emphasis on anticoagulant therapy.

METHODS

We retrospectively analyzed 2355 EGCs, including 137 lesions in patients treated under anticoagulants. Clinicopathological findings were evaluated between lesions in patients with and without anticoagulant therapy with propensity score matching analysis. The factors associated with post-ESD bleeding were analyzed with multivariate analysis with a logistic regression method.

RESULTS

After propensity score matching, post-ESD bleeding was significantly more frequent in lesions of patients with than without anticoagulant therapy (11.7% vs 1.5%, respectively; P = 0.001). A univariate analysis revealed that anticoagulant therapy, heparin bridge therapy, undifferentiated type, deep submucosal invasion, and resected specimen size were associated with post-ESD bleeding. A multivariate analysis revealed anticoagulant therapy (OR 23.1, 95% CI 3.61-147.52) and resected specimen size (OR 1.03, 95% CI 1.00-1.06) to be independent factors associated with post-ESD bleeding.

CONCLUSIONS

Anticoagulant therapy and resected specimen size were risk factors associated with post-ESD bleeding for EGC.

History and future perspectives in Japanese guidelines for endoscopic resection of early gastric cancer

Japanese guidelines for gastric cancer treatment were first published in 2001 for the purpose of showing the appropriate indication for each treatment method, thereby reducing differences in the therapeutic approach among institutions, and so on. With the accumulation of evidence and the development and prevalence of endoscopic submucosal dissection (ESD), the criteria for the indication and curability of endoscopic resection (ER) for early gastric cancer (EGC) have expanded. However, several problems still remain. Although a risk-scoring system (eCura system) for predicting lymph node metastasis (LNM) may help treatment decision in patients who do not meet the curative criteria for ER of EGC, which is referred to as eCura C-2 in the latest guidelines, additional gastrectomy with lymphadenectomy may be excessive for many patients, even those at high risk for LNM. Less-invasive function-preserving surgery, such as non-exposed endoscopic wall-inversion surgery with laparoscopic sentinel node sampling, may overcome this problem. In addition, further less-invasive treatment, such as ER with chemotherapy, should be established for patients who prefer not to undergo additional gastrectomy.

Current controversies in treating remnant gastric cancer: Are minimally invasive approaches feasible?

The incidence of remnant gastric cancer (RGC) is still increasing. Minimally invasive approaches including endoscopic resection, laparoscopic and robotic approaches, and function-preserving gastrectomy have been utilized as curative treatment methods for primary gastric cancer. However, adhesions and anatomical alterations due to previous gastrectomy make the use of minimally invasive approaches complicated and difficult for RGC. Application of these approaches for the treatment of RGC is still controversial. Endoscopic submucosal dissection is a favorable alternative therapy for the resection of early gastric cancer that occurs in the remnant stomach and can prevent unnecessary complications. The majority of retrospective studies have shown that endoscopic submucosal dissection is an effective and oncologically safe treatment modality for RGC. Subtotal gastrectomy could serve as a function-preserving gastrectomy for patients with early RGC and improve postoperative late-phase function. However, there are only two studies that demonstrate the feasibility and oncological efficacy of subtotal gastrectomy for RGC. The non-randomized controlled trials showed that compared to open gastrectomy, laparoscopic gastrectomy for RGC led to better short-term outcomes and similar oncologic results. Because of the rarity of RGC, future multicenter studies are required to determine the indications of minimally invasive treatment for RGC.

Short- and long-term outcomes of endoscopic submucosal dissection for early gastric cancer in the remnant stomach after gastrectomy

BACKGROUND

Endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) in the remnant stomach is a minimally invasive treatment. Few studies compared the technical difficulty of ESD involving the suture line and anastomosis, and information on long-term outcomes is insufficient. This study aimed to elucidate the short- and long-term outcomes of ESD for EGC in the remnant stomach.

METHODS

We investigated patients who underwent ESD for EGC in the remnant stomach between September 2002 and March 2016. Clinicopathological data were retrieved to assess en bloc resection rates, complications, and long-term outcomes including overall survival and cause-specific survival.

RESULTS

A total of 136 consecutive patients with 165 lesions resected by 157 ESD procedures were retrospectively evaluated. The en bloc resection rate was 95.5%. Complications included 16 intraoperative perforations (10.2%), 2 delayed perforations (1.3%), and 15 delayed bleeding (9.6%), which were successfully treated with endoscopy. The en bloc resection rate was significantly higher in the suture line group (100%) and the non-anastomosis or suture line group (98.8%) than in the anastomosis group (82.9%). However, the intraoperative perforation rate was significantly higher in the anastomosis group (31.4%) than in other groups. The 5-year overall and cause-specific survival rates were 88.4% and 97.6%, respectively, during a median follow-up period of 50.7 months (interquartile range 30.8-91.3).

CONCLUSIONS

The long-term outcomes of ESD for EGC in the remnant stomach were favorable. However, ESD involving the anastomosis was a technically demanding procedure due to the low en bloc resection rate and high perforation rate.