An Analysis of Delayed Bleeding in Cases of Colorectal Endoscopic Submucosal Dissection Due to Types of Direct Oral Anticoagulants in Japan.

BACKGROUND & AIMS: Reported rates of delayed bleeding (DB) after endoscopic resection using direct oral anticoagulants (DOACs) are high and heterogeneous. This large-scale multicenter study analyzed cases of DB after colorectal endoscopic submucosal dissection related to various types of DOACs in Japan (the ABCD-J study) with those associated with warfarin. METHODS: We retrospectively reviewed 1019 lesions in patients treated with DOACs and 459 lesions in patients treated with warfarin among 34,455 endoscopic submucosal dissection cases from 47 Japanese institutions between 2012 and 2021. The DB rate (DBR) with each DOAC was compared with that with warfarin. Risk factors for DB in patients treated with DOACs or warfarin were also investigated. RESULTS: The mean tumor sizes in the DOAC and warfarin groups were 29.6 ± 14.0 and 30.3 ± 16.4 mm, respectively. In the DOAC group, the DBR with dabigatran (18.26%) was significantly higher than that with apixaban (10.08%, P = .029), edoxaban (7.73%, P = .001), and rivaroxaban (7.21%, P < .001). Only rivaroxaban showed a significantly lower DBR than warfarin (11.76%, P = .033). In the multivariate analysis, heparin bridging therapy (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.27-3.73, P = .005), rectal location (2.01, 1.28-3.16, P = .002), and procedure time ≥55 minutes (2.43, 1.49-3.95, P < .001) were significant risk factors for DB in the DOAC group. The DB risk in the DOAC group (OR, (95% CI)) was 2.13 (1.30-3.50) and 4.53 (2.52-8.15) for 1 and 2 significant risk factors, respectively. CONCLUSIONS: Dabigatran was associated with a higher DBR than other DOACs, and only rivaroxaban was associated with a significantly lower DBR than warfarin.

[A case of autopsy-confirmed duodenal perforation due to calcium polystyrene sulfonate].

A 77-year-old male patient was referred to our hospital because of jaundice. He was diagnosed with alcoholic liver cirrhosis and was admitted to our hospital because of liver failure. After admission, we observed conservative liver disease, but the liver damage did not improve and gradually worsened. Renal function deteriorated during liver failure. Hyperkalemia presented due to renal dysfunction. Hence, calcium polystyrene sulfonate (CPS) was initiated. He died because of liver failure although hyperkalemia improved. An autopsy revealed ulcer perforation with CPS crystals in the duodenum. A basic substance considered a crystal of CPS was found by hematoxylin and eosin staining from the ulcer adjacent to the perforation and the exudate attached to the peritoneum. Furthermore, a large amount of CPS crystals were found in the ascites. A final diagnosis of gastrointestinal perforation peritonitis due to CPS was made. Gastrointestinal perforation due to CPS is presumed as a direct mucosal injury due to the drug, most of which is the sigmoid colon of elderly patients. Upper gastrointestinal tract perforation is extremely rare. We experienced a case of autopsy in which duodenal perforation due to CPS was pathologically confirmed. CPS is a widely used drug for renal disorders, but it has a risk of gastrointestinal injury. Therefore, a potential gastrointestinal mucosal injury should be considered when using CPS.

Depth of the cutting plane with underwater and conventional endoscopic mucosal resection: Post-hoc analysis of a randomized study.

BACKGROUND AND AIM: A multicenter randomized controlled trial reported a better R0 resection rate for intermediate-sized (10-20 mm) colorectal polyps with underwater endoscopic mucosal resection (UEMR) than conventional endoscopic mucosal resection (CEMR). To clarify whether UEMR removes enough submucosal tissue in the removal of unpredictable invasive cancers, we investigated the cutting plane depth with UEMR versus CEMR. METHODS: This was a post-hoc analysis of a randomized controlled trial in which 210 intermediate-sized colorectal polyps were removed in five Japanese hospitals. One pathologist and two gastroenterologists independently reviewed all resected specimens and measured the cutting plane depth. The cutting plane depth was evaluated as (i) maximum depth of submucosal layer and (ii) mean depth of submucosal layer, calculated using a virtual pathology system. RESULTS: We identified 168 appropriate specimens for the evaluation of the cutting plane depth, resected by UEMR (n = 88) and CEMR (n = 80). The median resection depth was not significantly different between UEMR and CEMR specimens, regardless of the measurement method ([i] 1317 vs 1290 µm, P = 0.52; [ii] 619 vs 545 µm, P = 0.32). All specimens in the UEMR and CEMR groups contained substantial submucosa and no muscularis propria. CONCLUSIONS: The cutting plane depth with UEMR was comparable with that with CEMR. UEMR can be a viable alternative method that adequately resects the submucosal layer for the histopathological assessment of unpredictable submucosal invasive cancers.

Magnifying Narrow-Band Imaging with Acetic Acid Spray for Superficial Non-Ampullary Duodenal Epithelial Tumors Based on the Mucin Phenotype.

INTRODUCTION: This study aimed to identify the characteristics of superficial non-ampullary duodenal epithelial tumors (SNADETs) based on the mucin phenotype using magnifying narrow-band imaging with acetic acid spray (MA-NBI) and evaluate the efficacy of MA-NBI in differentiating gastric-type (G-type) from intestinal-type (I-type) lesions. METHODS: We retrospectively identified 59 resected SNADETs in 59 patients who underwent MA-NBI. We evaluated surface patterns using MA-NBI to differentiate G-type from I-type lesions. Surface structures were classified into three patterns: tubular, villous, or oval structures. Lesions displaying a single pattern among the three patterns were classified as monotype, whereas those displaying multiple surface patterns were classified as mixed type. In addition, lesions with disorganized and unclear structures with irregular margins were classified as irregular surface structures. RESULTS: In total, 32 (54%), 26 (44%), and 1 (2%) lesions were classified as Vienna category 3, 4, and 5 tumors, respectively, whereas 49 (83%) and 10 (17%) were classified as I- and G-type lesions, respectively. Oval structures were more frequently observed in G-type lesions (70%), whereas tubular structures were more frequently observed in I-type lesions (78%) (p < 0.001). Category 4 and 5 lesions had significantly higher mixed and irregular surface structure rates than category 3 lesions (41 vs. 6%, p = 0.003 and 81 vs. 3%, p < 0.001, respectively). CONCLUSION: MA-NBI can distinguish the mucin phenotypes of SNADETs and may facilitate histological grade diagnosis.

Efficacy of Magnifying Narrow Band Imaging with Acetic Acid Spray in Diagnosing Superficial Non-Ampullary Duodenal Epithelial Tumors.

BACKGROUND/AIMS: The aim of the present study was to evaluate the efficacy of magnifying narrow band imaging with acetic acid spray (MA-NBI) in differentiating category 4/5 lesions from category 3 lesions of superficial non-ampullary duodenal epithelial tumors (SNADETs) as per Vienna Classification and to compare the diagnostic performances of both MA-NBI and magnifying narrow band imaging (M-NBI). METHODS: We retrospectively identified 60 resected SNADETs (31 category 3 lesions and 29 category 4/5 lesions) in 60 patients who underwent M-NBI and MA-NBI preoperatively. We evaluated vascular and surface patterns using M-NBI and MA-NBI for characterizing category 3 and 4/5 lesions. The surface pattern was classified as tubular, villous, or mix structure using MA-NBI. In addition, lesions with disorganized and unclear structures with irregular margins that can be clearly recognized by MA-NBI were defined as irregular surface structures. RESULTS: For MA-NBI, category 4/5 lesions had a significantly higher mix structure rate and higher irregular surface structure rate than category 3 lesions (62 vs. 16%, p < 0.001, and 86 vs. 19%, p < 0.001, respectively). The diagnostic accuracy of MA-NBI using mix and irregular surface structures for identifying category 4/5 lesions was as follows: sensitivity, 62/86%; specificity, 84/77%; positive predictive value, 78/78%; negative predictive value, 70/86%; and accuracy, 73/82%. The diagnostic accuracy of MA-NBI using irregular surface structure was significantly higher than that of M-NBI (p < 0.05). CONCLUSION: MA-NBI may be useful in differentiating between category 3 and category 4/5 lesions of SNADETs.

Comparison of Underwater vs Conventional Endoscopic Mucosal Resection of Intermediate-Size Colorectal Polyps.

BACKGROUND & AIMS: Endoscopic mucosal resection (EMR) with submucosal injection is an established method for removing colorectal polyps, although the en bloc resection rate decreases when polyp size exceeds 10 mm. Piecemeal resection increases local recurrence. Underwater EMR (UEMR) is an effective technique for removal of sessile colorectal polyps and we investigated whether it is superior to conventional EMR (CEMR). METHODS: We conducted a multicenter randomized controlled trial at 5 institutions in Japan. Patients with endoscopically diagnosed, intermediate-size (10-20 mm) sessile colorectal lesions were randomly assigned to undergo UEMR or CEMR. Only the most proximal lesion was registered. The UEMR procedure included immersion of the entire lumen in water and snare resection of the lesion without submucosal injection of normal saline. We analyzed outcomes of 108 colorectal lesions in the UEMR group and 102 lesions in the CEMR group. R0 resection was defined as en bloc resection with a histologically confirmed negative resection margin. The primary endpoint was the difference in the R0 resection rates between groups. RESULTS: The proportions of R0 resections were 69% (95% confidence interval [CI] 59%-77%) in the UEMR group vs 50% (95% CI 40%-60%) in the CEMR group (P = .011). The proportions of en bloc resections were 89% (95% CI 81%-94%) in the UEMR group vs 75% (95% CI 65%-83%) in the CEMR group (P = .007). There was no significant difference in median procedure time (165 vs 175 seconds) or proportions of patients with adverse events (2.8% in the UEMR group vs 2.0% in the CEMR group). CONCLUSIONS: In a multicenter randomized controlled trial, we found that UEMR significantly increased the proportions of R0 resections for 10- to 20-mm sessile colorectal lesions without increasing adverse events or procedure time. Use of this procedure should be encouraged. Trials registry number: UMIN000018989.

[A case of concomitant pancreatic neuroendocrine neoplasm and intraductal papillary mucinous neoplasm in which preoperative diagnosis was difficult].

A 75-year-old male patient has been followed-up for mixed-type intraductal papillary mucinous neoplasm (IPMN) in the tail of the pancreas for about 20 years. Upon close examination, he was diagnosed of high-risk stigmata due to a nodule having a contrast effect of 5mm or more in the tumor. Based on this, a distal pancreatectomy was performed. Histopathological analysis revealed concomitant IPMN (low-grade) and pancreatic neuroendocrine neoplasm (PNEN) (G1). This prompted us to report a very rare case of coexisting PNEN and IPMN with an interesting pathological finding that might suggest its pathogenic mechanism.

[A case of relapsed hemosuccus pancreaticus successfully treated with interventional radiology].

A 67-year-old male with chronic pancreatitis presented with upper abdominal pain and melena. Abdominal dynamic computed tomography revealed a splenic artery aneurysm in the main pancreatic duct. Esophagogastroduodenoscopy showed active bleeding from Vater's papilla. The patient was diagnosed with hemosuccus pancreaticus (HP) due to rupture of the aneurysm and treated with interventional radiology (IVR). The patient's poor lung function did not allow for a radical operation and a follow-up examination was recommended. The HP relapsed 7 months later and was successfully retreated with IVR. Although IVR is associated with a high recurrence rate, it is less invasive and therefore effective for treating relapsing HP in patients with a poor general condition.

[A patient with sepsis and a gas-forming liver abscess caused by Clostridium perfringens treated with continuous perfusion drainage].

A 64-year-old man presented with diarrhea, fever, and disturbance of consciousness; he was subsequently diagnosed with acute renal and hepatic disorder. Abdominal computed tomography identified a gas-forming liver abscess, and the patient underwent emergency drainage. However, his condition did not improve, and Clostridium perfringens was observed in his blood culture. Continuous perfusion drainage was performed by placing an additional drainage tube, which resulted in abscess shrinkage and improved the patient's general condition. Despite the low survival rate in patients with gas-forming liver abscesses caused by C. perfringens, therapy was successful in this patient.

Digestive disease management in Japan: a report on the 6th diagnostic pathology summer fest in 2012.

The 6th Diagnostic Pathology Summer Fest, held in Tokyo on August 25-26, 2012, opened its gates for everyone in the medical profession. Basic pathology training can contribute to the improvement of algorithms for diagnosis and treatment. The 6th Summer Fest with the theme 'Pathology and Clinical Treatment of Gastrointestinal Diseases' was held at the Ito International Research Center, The University of Tokyo. On August 25, 'Treatment of Early Gastrointestinal Cancer and New Guidelines' was discussed in the first session, followed by 'Biopsy Diagnosis of Digestive Tract: Key Points of Pathological Diagnosis for Inflammation and Their Clinical Significance' in the second session. On August 26, cases were discussed in the third session, and issues on pathological diagnosis and classification of neuroendorcrine tumor in the fourth session. The summaries of speeches and discussions are introduced along with the statements of each speaker. This meeting was not a formal evidence-based consensus conference, and 20 experts gave talks on their areas of specialty. Discussion was focused on how the management strategy should be standardized on the algorithm of patient care.

Immunohistochemical analysis of the DNA methyltransferase 3b expression is associated with significant improvements in the discrimination of ulcerative colitis-associated neoplastic lesions.

PURPOSE: Making a clinicopathological diagnosis of dysplasia is crucial. We herein assess the significance of the DNA methyltransferase 3b (DNMT3b) expression as a diagnostic marker of ulcerative colitis (UC)-associated neoplasia. METHODS: Thirty-one patients with long-standing and extensive UC were included in this study. The expression of DNMT3b in non-neoplastic rectal epithelium (non-dysplasia in 31 patients) and colorectal neoplasia (dysplasia in 43 patients and invasive cancer in 34 patients) was determined using immunohistochemistry. The presence of immunoreactive DNMT3b was assessed in the areas with the highest density of cells with positively staining nuclei. DNMT3b was expressed as the percentage of positive cells relative to the total number of cells counted under high power magnification. RESULTS: The DNMT3b expression in neoplastic rectal epithelium (0.76, range 0.59-0.84) was increased compared to that observed in non-neoplastic epithelium (0.32, range 0.18-0.67, P < 0.001). A ROC curve analysis confirmed 0.68 to be the best diagnostic cut-off value for the DNMT3b expression in neoplastic epithelium (area under the curve = 0.810). The sensitivity of the diagnostic test was 66.2 %, the specificity was 86.7 %, the positive predictive value was 95.7 % and the negative predictive value was 36.1 %. The positive likelihood ratio was 4.98 and the negative likelihood ratio was 0.20. The accuracy was 69.9 %. CONCLUSIONS: An immunohistochemical analysis of the DNMT3b expression was associated with significant improvements in the discrimination of UC-associated neoplastic lesions.

Late recurrence of early gastric cancer 11 years after curative endoscopic submucosal dissection.

A 73-year-old man was initially diagnosed with a 50-mm, depressed-type early gastric cancer on the anterior wall of the angulus, and the lesion was curatively resected en bloc by endoscopic submucosal dissection. Pathology revealed a 54 mm × 43 mm differentiated-type predominant adenocarcinoma with focal undifferentiated-type component that was confined to the mucosa without ulceration. Eleven years after endoscopic submucosal dissection, lymph node metastasis along the lesser curve was incidentally detected on magnetic resonance imaging and diagnosed by endoscopic ultrasound-guided fine-needle aspiration biopsy. The patient received distal gastrectomy with D2 lymph node dissection. A resected lymph node revealed a well-differentiated adenocarcinoma with a poorly differentiated component; thus, the final diagnosis was late recurrence of early gastric cancer originally treated by endoscopic submucosal dissection. This report demonstrates that metastatic recurrence may occur in curative endoscopic submucosal dissection for early gastric cancer and that gastric cancer can recur even after more than 5 years.

Immunohistochemical analysis of REG Iα expression in ulcerative colitis-associated neoplastic lesions.

BACKGROUND AND AIMS: The regenerating gene (REG)Iα has been identified by microarray analysis as a gene that is distinctly overexpressed in ulcerative colitis (UC), and its protein product is suggested to play a pivotal role in the development of UC-associated carcinoma. In the present study, we investigated the significance of REG Iα expression as a diagnostic marker of UC-associated neoplasia. METHODS: Tissue samples were obtained from colectomy specimens from 31 patients with long-standing UC (mean disease duration 17.2 years, range 5-29). The lesions were evaluated according to the International Classification for Dysplasia in Inflammatory Bowel Diseases, and the sections were examined using immunohistochemistry for REG Iα and p53. RESULTS: In the 'regenerating atypia' group, REG Iα immunoreactivity was restricted to the lower third of the UC mucosa (grade 1). Lesions classified as 'indefinite for dysplasia' also showed predominantly basal-type staining for REG Iα. However, in 'low-grade dysplasia' and 'high-grade dysplasia' lesions, the localization of REG Iα immunoreactivity expanded to the middle (grade 2) and upper (grade 3) third of the UC mucosa, respectively. The REG Iα immunostaining pattern differed significantly (p < 0.0001) between non-neoplastic and neoplastic lesions, and was significantly (p < 0.0001) associated with p53 overexpression. CONCLUSIONS: Immunohistochemical analysis of REG Iα expression is useful for differential diagnosis of non-neoplastic and neoplastic lesions in UC tissues.

Endoscopic features of sessile serrated adenoma and other serrated colorectal polyps.

BACKGROUND/AIMS: Sessile serrated adenoma is a subtype of serrated colorectal polyps that can potentially give rise to colorectal carcinoma. We aimed to characterize the endoscopic features of sessile serrated adenoma as compared to those of other subtypes of serrated colorectal polyps. METHODOLOGY: A total of 202 serrated colorectal polyps were retrospectively collected and pathologically subclassified as sessile serrated adenoma, hyperplastic polyp, or traditional serrated adenoma. The patients' demographics and endoscopic findings were reviewed, and comparisons were made between groups. RESULTS: We found 57 sessile serrated adenomas, 104 hyperplastic polyps, and 41 traditional serrated adenomas. Sessile serrated adenomas were larger in size, and they had more granular or nodular surface and more irregular or vague margin than hyperplastic polyps; however, these two subgroups were similar in terms of their sessile configuration and white coloring. Sessile serrated adenomas could be distinguished from traditional serrated adenomas based on the pedunculated configuration and red coloring unique to the traditional serrated adenomas. Nine sessile serrated adenomas were of note due to coverage with abundant mucus, which was rarely seen in other subgroups. CONCLUSIONS: We characterize the endoscopic features of sessile serrated adenoma as compared to those of hyperplastic polyp and traditional serrated adenoma.

Gastric Cancer with Multiple Lymph Node Enlargement at the Time of the Sarcoidosis Diagnosis.

An 80-year-old woman was found to have a 40-mm depressed-type gastric cancer. Computed tomography showed multiple lymph node enlargement, including paraaortic lymph nodes. The extent of lymph node enlargement was significant compared with the depth of the primary lesion. We conducted distal gastrectomy, D2 lymph node dissection, and a paraaortic lymph node biopsy. Microscopically, the tumor was diagnosed as mucosal cancer. In the dissected lymph nodes, noncaseating granuloma was found without metastasis of adenocarcinoma. Immunohistochemical staining using Propionibacterium acnes-specific antibodies showed a large number of P. acnes-positive cells in the granulomas. Finally, the tumor was diagnosed as early-stage gastric cancer and sarcoidosis.

Upper Gastrointestinal Langerhans Cell Histiocytosis: A Report of 2 Adult Cases and a Literature Review.

Langerhans cell histiocytosis (LCH) with primary involvement of the upper gastrointestinal (GI) tract is rare. We report 2 adult cases of localized LCH in the upper-GI tract, including the second reported adult case of esophageal LCH and review 11 previously reported cases. Case 1 involved the esophagus of a 61-year-old man; histiocytosis was detected when endoscopy was performed for an examination of epigastric pain. Case 2 involved the stomach of a 56-year-old woman wherein the lesion was detected during a follow-up endoscopy after Helicobacter pylori infection. Both biopsy specimens exhibited diffuse proliferation of mononuclear cells with nuclear convolution and a background of eosinophilic infiltrate. The cells were immunohistochemically positive for CD1a and langerin, and BRAF V600E mutation was detected in Case 2. Follow-up endoscopy for both cases revealed that the lesions disappeared without any treatment. It is important to avoid misdiagnosing LCH of the upper-GI tract as a malignant neoplasm.