Preceding endoscopic submucosal dissection in submucosal invasive gastric cancer patients does not impact clinical outcomes.

Submucosal deep invasion of gastric cancer (T1b2; depth of submucosal invasion ≥ 500 µm) is a risk factor for lymph node metastasis and, thus, is one of the criteria for curative treatment. Our aim was to evaluate the specific influence of endoscopic submucosal dissection (ESD) on the prognosis of patients with T1b2 gastric cancer. This was a retrospective analysis of 248 consecutive patients, with 252 pT1b2 gastric cancer lesions, who underwent ESD prior to additional surgery (Group A, n = 101) or surgery only (Group B, n = 147). After propensity score-matching (for sex, age, tumor diameter and gross type), we compared pathological characteristics between the 2 groups and the prognosis over a follow-up period ≥ 60 months. Compared to Group B, patients in Group A were older, with a higher proportion of men. The proportion of depressed and undifferentiated type tumors was greater in Group B than A, with larger tumor size and depth of submucosal invasion as well. There was no incidence of local recurrence, but distant metastasis was identified in 5% of cases in Group A and 3% in Group B. After propensity score-matching, there were no difference in the 5-year overall survival rate between Group A and B (87.5% vs. 91.2%, respectively), nor in the 5-year disease-specific survival rate (96.3% vs. 96.4%, respectively). ESD prior to surgery for T1b2 gastric cancer did not adversely affect clinical outcomes after additional surgery.

Usefulness of linked color imaging in the early detection of superficial esophageal squamous cell carcinomas.

BACKGROUND AND AIMS: Linked color imaging (LCI) improved the visibility of gastric cancer and colorectal flat lesions. This study aimed to investigate the usefulness of LCI in detecting superficial esophageal squamous cell carcinomas (SESCC). METHODS: We enrolled 37 consecutive SESCC patients (46 SESCCs) diagnosed using LCI and blue laser imaging bright mode (BLI-BRT) and treated in Hiroshima University Hospital between April 2018 and November 2018. Eight professional endoscopists compared images obtained on non-magnifying BLI-BRT and LCI versus conventional white light imaging (WLI). Identification and boundary diagnosis of SESCC with LCI and BLI-BRT were compared with WLI. Changes in lesion visibility were clarified. Interobserver agreement was assessed. Clinicopathological features of lesion that influence visibility with LCI were assessed. RESULTS: In LCI, 37% (17/46) of cases had improved visibility and 63% (29/46) had unchanged visibility (interobserver agreement = 0.74). Among cases with multiple lugol voiding lesions (LVLs), ΔE between the lesion and background mucosa was significantly higher in LCI than in WLI (20.8 ± 7.9 vs 9.2 ± 6.1, P < 0.05). No significant differences were found in tumor size, morphological type, color, depth, and smoking or drinking history. However, multiple LVLs were significantly higher among cases with improved versus unchanged visibility. On BLI-BRT, 39% (18/46) of cases had improved visibility and 61% (28/46) had unchanged visibility (interobserver agreement = 0.60). CONCLUSION: Almost the same as BLI-BRT, LCI improves SESCC visibility compared with WLI. This is useful for cases with multiple LVLs. In cases without background coloration (BGC), LCI may make SESCC more visible than BLI-BRT.

Stromal reaction inhibitor and immune-checkpoint inhibitor combination therapy attenuates excluded-type colorectal cancer in a mouse model.

Despite recent advances in cancer immunotherapy, the efficacy of colorectal cancer (CRC) immunotherapy regimens is limited. This study evaluated the combined effect of an anti-PD-1 antibody and a platelet-derived growth factor receptor inhibitor (imatinib) on CRC progression using an orthotopic transplanted mouse model that reproduced the three histological phenotypes of CRC (inflamed-, excluded-, and desert-type). The frequency of each of these phenotypes in 196 human CRC tissue samples was also evaluated. Excluded-type CRC had the highest frequency in human tissue samples. In the mouse model, imatinib suppressed stromal reaction and increased sensitivity to anti-PD-1 treatment in excluded-type CRC. Antitumor effect was observed in mice with excluded-type tumors only after concomitant administration of anti-PD-1 antibody and imatinib. Immunohistological analysis revealed a reduction in stromal volume and an increase in the number of CD8-positive T cells in the tumor nest following combination therapy. RNA sequencing revealed significant activation of immune-related pathways and suppression of stromal-related pathways in transplanted tumors treated with combination therapy compared with tumors treated with anti-PD-1 antibody monotherapy. This combination therapy may prove effective for CRC cases that are unresponsive to anti-PD-1 antibody monotherapy.

Clinical significance of endoscopic ultrasonography in diagnosing invasion depth of early gastric cancer prior to endoscopic submucosal dissection.

BACKGROUND AND AIM: Endoscopic ultrasonography is a reliable diagnostic modality for determining indications of endoscopic submucosal dissection for early gastric cancer. We aimed to clarify the clinical significance of endoscopic ultrasonography in the invasion depth diagnosis of early gastric cancer. METHODS: We retrospectively assessed 1598 consecutive patients with 2001 early gastric cancers who underwent EUS before ESD or surgery between October 2010 and April 2019 at our institution. Lesions were classified according to endoscopic ultrasonography-determined invasion depth as EUS-M/SM1 (lesions confined to sonographic layers 1 and 2 or lesions with changes in sonographic layer 3; depth, < 1 mm) and EUS-SM2 (lesions with changes in sonographic layer 3; depth, ≥ 1 mm). We evaluated the invasion depth determination accuracy of endoscopic ultrasonography and analyzed the clinicopathological features of misdiagnosed early gastric cancer cases. RESULTS: The invasion depth determination accuracy was as follows: EUS-M/SM1: pathological T1a/T1b1 early gastric cancer, 97%; EUS-SM2: pathological T1b2 early gastric cancer, 79%. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 95%, 98%, 69%, 97%, and 79%, respectively. In EUS-M/SM1 early gastric cancer, tumor size of ≥ 15 mm, presence of ulceration, and undifferentiated histological type were significantly associated with endoscopic ultrasonography accuracy. In EUS-SM2 early gastric cancer, tumor size of ≥ 30 mm was significantly associated with endoscopic ultrasonography accuracy. CONCLUSIONS: Endoscopic ultrasonography is a useful modality in accurately determining the invasion depth of early gastric cancer before endoscopic submucosal dissection.

Clinical and genomic characteristics of mucosal signet-ring cell carcinoma in Helicobacter pylori-uninfected stomach.

BACKGROUND: Gastric cancer develops even in Helicobacter pylori(H. pylori)-uninfected patients and its typical histological feature is signet ring cell carcinoma (SRCC) within the mucosal layer. However, the biological characteristics of SRCC remain unclear. We aimed to clarify the pathological and genetic features of SRCC in H. pylori-uninfected patients. METHODS: Seventeen H. pylori-uninfected patients with mucosal SRCCs were enrolled and their clinicopathological characteristics were compared with those of H. pylori-infected patients with mucosal SRCCs. Seven SRCCs without H. pylori-infected, including two invasive SRCCs, and seven H. pylori-infected SRCCs were subjected to a genetic analysis using next-generation sequencing. RESULTS: H. pylori-uninfected patients with mucosal SRCCs revealed male dominancy and a significantly higher prevalence of smokers among them as compared with the H. pylori-infected patients with SRCC. A CDH1 mutation (frame shift indel) was detected in one H. pylori-uninfected cancer not only in the mucosal SRCC but also in the invasive portion. A TP53 mutation was detected in one SRCC without H. pylori-infected. In the control group, ARID1A and TP53 mutations were detected in one SRCC each. The C to A mutation, which is a characteristic smoking-induced mutation, was not found in any of the samples. CONCLUSIONS: Some SRCCs in H. pylori-uninfected patients may have a malignant potential similar to that of SRCCs in H. pylori-infected patients. Smoking may not be the main carcinogenic factor for the development of SRCCs among the H. pylori-uninfected patients.

Clinical outcomes of endoscopic resection for superficial non-ampullary duodenal tumors.

Background and study aims Because superficial non-ampullary duodenal epithelial tumors (SNADETs) are relatively rare, studies evaluating the outcomes of endoscopic resection (ER) for SNADETs are limited. Therefore, this study aimed to evaluate the clinical validity of ER for SNADETs. Patients and methods The study participants included 163 consecutive patients (108 men; mean age, 61.5 ±â€Š11.3 years) with 171 SNADETs, excluding patients with familial adenomatous polyposis resected by ER, at Hiroshima University Hospital between May 2005 and September 2016. Clinicopathological features and the outcomes of ER for 171 cases were retrospectively analyzed. Additionally, the prognosis of 135 patients with more than 12 months' follow-up was analyzed. Results Mean diameter of SNADETs was 10.7 ±â€Š7.2 mm. Most of the SNADET cases were classified as category 3 (71 %, 121/171), but some were category 5 (2 %, 3/171). En bloc resection rates were 93 % (146/157), 100 % (7/7), and 86 % (6/7) in endoscopic mucosal resection (EMR), polypectomy, and in endoscopic submucosal dissection (ESD) cases, respectively. Complete resection rates were 90 % (141/157), 100 % (7/7), and 71 % (5/7) in EMR, polypectomy, and ESD cases, respectively. Emergency surgery was performed in two patients with intraoperative perforation and in two with delayed perforation without artificial ulcer bed closure after ER. Since endoscopic closure of ulcer by clipping was performed, delayed perforation has not occurred. Local recurrence occurred in 1.2 %, but no metastasis to lymph nodes or other organs occurred after ER. No patient died of primary SNADETs. Conclusion Our data supported the clinical validity of ER for SNADETs. However, delayed perforation should be given much attention.

The Evaluation of Esophageal Motility Using Infusion Manometry with a Trans-nasal Endoscope: A Preliminary Study.

Objective The Chicago classification using high-resolution manometry (HRM) has been proposed for the diagnosis of esophageal motility disorders. However, HRM is expensive, and few patients are likely to benefit from this method. We established a method using a raised infusion catheter called "esophageal manometry using a trans-nasal endoscope". In this study, we examined the clinical utility of this new method for the assessment of patients with dysphagia. Methods We enrolled 124 consecutive patients who complained of dysphagia and were suspected of having esophageal motility disorders. Patients underwent manometry using a trans-nasal endoscope at Hiroshima University Hospital from September 2008 to December 2018. An esophageal biopsy was performed during the procedure from the thoracic esophagus to detect eosinophilic esophagitis. In addition, we examined the clinical courses of patients diagnosed with achalasia. Results The diagnostic ability of manometry using a trans-nasal endoscope was 98%, and no major complications associated with the procedure were recorded. About 30% of patients were diagnosed with achalasia, and most (77%) were well controlled by medications or balloon dilation. One patient was diagnosed with eosinophilic esophagitis. Conclusion Manometry using a trans-nasal endoscope is beneficial and can be used for the clinical management of patients with dysphagia.

Clinical Usefulness of Dual Red Imaging in Gastric Endoscopic Submucosal Dissection: A Pilot Study.

BACKGROUND/AIMS: Dual red imaging (DRI) is a new, image-enhanced endoscopy technique. There are few reports about the usefulness of DRI during gastric endoscopic submucosal dissection (ESD). We aimed to examine the usefulness of DRI in endoscopic hemostasis during gastric ESD. METHODS: We enrolled a total of 20 consecutive patients who underwent gastric ESD. Five endoscopists compared DRI with white light imaging (WLI) for the visibility of blood vessels and bleeding points while performing endoscopic hemostasis. RESULTS: The visibility of blood vessels was increased in 56% (19/34) of the cases, and the visibility of bleeding points was improved in 55% (11/20) of the cases with the use of DRI compared with the use of WLI. CONCLUSION: DRI improved the visibility of blood vessels and bleeding points in cases with oozing bleeding, blood pooling around the bleeding points, and multiple bleeding points.

Potential of Helicobacter pylori-uninfected signet ring cell carcinoma to invade the submucosal layer.

BACKGROUND AND AIM: The typical histology of Helicobacter pylori-uninfected gastric cancer is signet ring cell carcinoma (SRCC) localized in the mucosal layer, but the potential of these SRCCs to invade the submucosal layer is unclear. This study aimed to investigate the clinicopathological characteristics of SRCC in H. pylori-uninfected patient and its prevalence in diffuse-type gastric cancer (DGC) within Japan. METHODS: We enrolled consecutive pure DGC patients diagnosed with the disease either localized in the mucosal layer or with submucosal invasion. H. pylori infection was investigated, and the patients were divided into three groups according to histological types: pure SRCC, SRCC with poorly differentiated adenocarcinoma (PDA), and pure PDA. RESULTS: Of the 345 pure DGC patients, 132 (38%), 127 (37%), and 86 (25%) had pure SRCC, SRCC with PDA, and pure PDA histologies, respectively. The prevalence of H. pylori infection and the SM ratio were significantly lower in the pure SRCC group than other groups (P < 0.01). Twenty-two (6.4%) patients, including two with submucosal invasion, were negative for H. pylori and had mucosal SRCC component in the cancer lesions. Of the 259 SRCC cases (pure SRCC or SRCC + PDA), H. pylori-uninfected cases had different clinicopathological characteristics compared with H. pylori-positive cases. Particularly, the ratio of patients with submucosal invasive SRCC was significantly lower in the H. pylori-uninfected gastric cancer group than in those with H. pylori infection. CONCLUSION: Helicobacter pylori-uninfected gastric cancer is not rare among pure DGC patients in Japan. SRCC in patients without H. pylori infection is less likely to be invasive.

Gastric Cancer with Submucosal Invasion after Successful Helicobacter pylori Eradication: A Propensity Score-Matched Analysis of Patients with Annual Patient Endoscopic Survey.

BACKGROUND AND AIM: The incidence of gastric cancer occurring after successful Helicobacter pylori eradication has been increasing. We aimed to clarify the influence of eradication therapy on the ability to diagnose early gastric cancer after successful H. pylori eradication in patients who underwent annual endoscopic screening. METHODS: A total of 220 patients (179 men; mean age 71.0 years) had differentiated-type early gastric cancer that was discovered through annual endoscopic screening. Patients were categorized into 2 groups: the H. pylori-eradicated group (n = 81) and the non-eradicated control group (n = 139). After matching patients by propensity scores, we retrospectively analyzed the clinicopathological characteristics of 162 patients (81 patients in each group). Furthermore, we compared the characteristics of gastric cancer with submucosal invasion between the 2 groups. RESULTS: The prevalence of early gastric cancer with submucosal invasion was significantly higher in the eradicated group than in the control group, both before propensity score matching (16.0 vs. 7.2%, respectively; p = 0.038) and after propensity score matching of 81 pairs (16.0 vs. 4.9%, respectively; p = 0.021). In the comparative analysis of gastric cancer with submucosal invasion, there was no difference between the 2 groups with respect to factors influencing the ability to diagnose its presence endoscopically. CONCLUSION: H. pylori eradication therapy increased the prevalence of differentiated-type gastric cancer with submucosal invasion despite patients' completion of annual endoscopic screening after eradication.

Taking Warfarin with Heparin Replacement and Direct Oral Anticoagulant Is a Risk Factor for Bleeding after Endoscopic Submucosal Dissection for Early Gastric Cancer.

BACKGROUND: Although bleeding after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) remains problematic, especially in patients taking anticoagulants, there are differing views on the ideal and optimal management for these patients. This study investigated the risk of bleeding after ESD in patients taking anticoagulants. METHODS: We enrolled 61 consecutive patients taking anticoagulants (anticoagulant group) and 968 patients taking no antithrombotic agents (non-antithrombotic group) treated with ESD for EGC between December 2010 and October 2016. We analyzed the risk factors for bleeding after ESD in relation to the various clinical factors. RESULTS: Incidences of bleeding after ESD were significantly higher (14%; 11/76) in the anticoagulant group compared to the non-antithrombotic group (3%; 40/1,167). Moreover, bleeding after ESD was significantly more common in patients in the warfarin monotherapy group (14%; 5/37) and in the direct oral anticoagulant (DOAC) monotherapy group (22%; 4/18), compared to the non-antithrombotic group. Multivariate analysis revealed that dialysis, the use of anticoagulants, and an operation time ≥75 min were independent risk factors for bleeding after ESD. CONCLUSIONS: Our data suggest that patients who take warfarin and receive heparin bridging, and those who take DOAC medication, are prone to bleeding after ESD for EGC.