[A case of incipient pancreatic ductal adenocarcinoma concomitant with intraductal papillary mucinous neoplasm, confirmed by multiregion sequencing analysis].

Concomitant pancreatic ductal adenocarcinoma (PDA) is observed in a subset of patients with intraductal papillary mucinous neoplasm (IPMN) of the pancreas, and early detection of those progressing lesions is difficult. We present a case with a de novo carcinoma in situ (CIS) discovered incidentally around the resection margin of IPMNs. A man in his 70s with a history of acute pancreatitis at the age of 50 years and no family history of PDA had a pancreatoduodenectomy for three isolated branch duct IPMNs that caused recurrent pancreatitis. During the 2-year follow-up period, the index lesion in the pancreatic head grew significantly, whereas the other cysts remained small and without mural nodules. The majority of the cysts are histologically composed of low-grade dysplasia and are classified as gastric-type IPMN. CIS with nuclear overexpression of p53 was located in the main pancreatic duct and adjacent brunch duct, which involved the pancreatic resection margin. The precise pathological analysis combined with multiregion sequencing revealed the CIS harbored KRAS G12V and TP53 R248W. Conversely, IPMNs contained GNAS mutant cells as well as components containing additional KRAS mutations. These findings suggested that the CIS formed independently of the multiple IPMNs and appeared to be an early manifestation of concomitant PDA with coexisting IPMNs. Despite widespread agreement on the resection of the radiographically significant IPMN lesion (s), the latent invasive cancer was not eradicated. A detailed pathological and molecular assessment of the resected materials may aid in a better management strategy for concurrent lesions.

Efficacy and adverse events of EMR and endoscopic submucosal dissection for the treatment of colon neoplasms: a meta-analysis of studies comparing EMR and endoscopic submucosal dissection.

BACKGROUND: EMR and endoscopic submucosal dissection (ESD) are used frequently to remove colon neoplasms. However, the predominance of these procedures has not yet been thoroughly explored. OBJECTIVE: To compare the efficacy and adverse events related to EMR with those related to ESD for colon neoplasms. DESIGN: A meta-analysis of 8 studies published between 2005 and 2013. SETTING: Multicenter review. PATIENTS: Patients from 8 studies yielding 2299 lesions. INTERVENTIONS: EMR or ESD. MAIN OUTCOME MEASUREMENTS: En bloc resection, curative resection, recurrence, and adverse events. RESULTS: The pooled odds ratios (OR) (OR [95% confidence interval]) for the tumor size, length of the procedure, en bloc resection, curative resection, recurrence, additional surgery, delayed bleeding, and perforation by ESD versus EMR were 7.38 (6.42-8.34), 58.07 (36.27-79.88), 6.84 (3.30-14.18), 4.26 (3.77-6.57), 0.08 (0.04-0.17), 2.16 (1.16-4.03), 0.85 (0.45-1.60), and 4.96 (2.79-8.85), respectively. LIMITATIONS: This analysis included only nonrandomized studies. CONCLUSION: The size of the tumor and rate of en bloc resection and curative resection were higher, and the rate of recurrence was lower in the ESD group versus the EMR group. However, in the ESD group, the procedure was longer, and the rate of additional surgery and perforation was higher, suggesting that the indications for ESD should therefore be rigorously determined in order to avoid such problems.

Decreased numbers of vascular networks and irregular vessels on narrow-band imaging are useful findings for distinguishing intestinal lymphoma from lymphoid hyperplasia.

BACKGROUND: No method for sufficiently making the differential diagnosis of intestinal lymphoma resembling lymphoid hyperplasia (LH) on endoscopy has yet been established. OBJECTIVE: The aim of this study was to evaluate the usefulness of narrow-band imaging (NBI) in diagnosing intestinal lymphoma. DESIGN: Prospective study. SETTING: Single-center study. PATIENTS: Sixty-one patients with primary or systemic lymphoma were enrolled in this study. INTERVENTIONS: The terminal ileum and entire colon were observed by using conventional endoscopy. NBI was subsequently performed when small polypoid lesions were detected. A decrease in the number of vascular networks (DVNs) and the presence of irregular vessels on the surface of the epithelia were defined as characteristic findings of intestinal lymphoma. The diagnostic accuracy of these 2 findings in distinguishing intestinal lymphoma from LH was examined. MAIN OUTCOME MEASUREMENTS: The ability to use NBI to distinguish intestinal lymphoma from LH. RESULTS: Two hundred ninety-four small polypoid lesions, including 59 lymphomas and 235 LH lesions, were detected. The rates of detecting DVNs and the presence of irregular vessels were significantly higher in the lymphoma samples (81.4% and 62.7%) than in the LH samples (25.5% and 4.7%). Based on these findings, the diagnostic accuracy, sensitivity, specificity, and positive and negative predictive values for differentiating intestinal lymphoma from LH were 88.8%, 62.7%, 95.3%, 77.1%, and 91.1%, respectively, which are significantly higher than those of conventional endoscopy. LIMITATIONS: Single-center study. CONCLUSION: DVNs and the presence of irregular vessels on NBI are thus considered to be useful findings for differentiating intestinal lymphoma from benign LH.

Reduction of E-cadherin by human defensin-5 in esophageal squamous cells.

Barrett's esophagus (BE) is metaplastic columnar epithelium converted from normal squamous epithelia in the distal esophagus that is thought to be a precancerous lesion of esophageal adenocarcinoma. BE is attributed to gastroesophageal reflux disease (GERD), and therefore gastric acid or bile acids are thought to be factors that cause epithelial cell damage and inflammation in the gastro-esophageal junction. The decrease of adherent junction molecules, E-cadherin has been reported to be associated with the progression of the Barrett's carcinoma, but the initiation of BE is not sufficiently understood. BE is characterized by the presence of goblet cells and occasionally Paneth cells are observed at the base of the crypts. The Paneth cells possess dense granules, in which human antimicrobial peptide human defensin-5 (HD-5) are stored and secreted out of the cells. This study determined the roles of HD-5 produced from metaplastic Paneth cells against adjacent to squamous cells in the gastro-esophageal junction. A human squamous cell line Het-1A, was incubated with the synthetic HD-5 peptide as a model of squamous cell in the gastro-esophageal junctions, and alterations of E-cadherin were investigated. Immunocytochemistry, flowcytometry, and Western blotting showed that the expression of E-cadherin protein was decreased. And a partial recovery from the decrease was observed by treatment with a CD10/neprilysin inhibitor (thiorphan). In conclusion, E-cadherin expression in squamous cells was reduced by HD-5 using in vitro experiments. In gastro-esophageal junction, HD-5 produced from metaplastic Paneth cells may therefore accelerate the initiation of BE.

[Primary diaphragmatic schwannoma which needed to be distinguished from a liver tumor].

A 55-year-old woman was admitted because of a tumor located in the ventral region of S4 of the liver, just beneath the diaphragm. A CT scan revealed the round tumor to be delineated as a 33 mm in size, with an outer capsule. The tumor was visualized as concentric circles which presented high-, low-, and high- signal patterns on T2-weighted MRI. It also presented a triphasic pattern in which the border and the central part were not contrasted as a low signal pattern, while the middle part was contrasted as a high signal pattern by T1-weighted enhanced imaging with Gd-DTPA. Angiography revealed that the tumor did not originate from the liver but from the diaphragm, so it was surgically resected as a primary diaphragmatic tumor. We report a schwannoma which originated from the diaphragm, that showed characteristic imaging findings and required to be distinguished from a liver tumor.

Genetic Tracing of Clonal Expansion and Progression of Pancreatic Ductal Adenocarcinoma: A Case Report and Multi-Region Sequencing Analysis.

Pancreatobiliary tumors frequently contain multiple malignant and precancerous lesions; however, the origin of the driver mutations and the mechanisms that underlie the generation of distinct clones within an organ field remain unclear. Herein, we describe a 76-year-old male suffering from moderately differentiated adenocarcinomas of the pancreas that primarily involved the distal bile duct and multiple "dispersing" invasive lesions in the pancreatic head. The patient underwent pylorus-preserving pancreaticoduodenectomy with superior mesenteric vein resection, and targeted sequencing of 18 genes associated with pancreatic tumorigenesis and immunohistochemical analysis of RNF43 and ARID1A were performed on each tumor compartment, including the invasive and non-invasive areas. Multi-region sequencing revealed shared KRAS and TGFBR1 mutations in all invasive foci, including those involving the distal bile duct. Distinct KRAS variants were found to be present in other non-continuous and non-invasive lesions in the pancreas. Intraductal lesions with KRAS G12D and RNF43 V50R mutations were evident in the main pancreatic duct. This appeared to be a founder clone, given that the mutation profile was common to the invasive foci as well as the additional high-grade dysplasia harboring ARID1A mutations, thereby suggesting a clonal branch-off during tumor evolution. In addition, we also observed independent intraductal papillary mucinous neoplasms with KRAS G12V and GNAS R201H mutations. Our theory, learned from this patient, was that lesions skipped dissemination and wide-spread movement potentially through the pancreatic ductal system as a process of pancreatic cancer development.

A randomized study on the effectiveness of prophylactic clipping during endoscopic resection of colon polyps for the prevention of delayed bleeding.

BACKGROUNDS: The efficacy of clipping for preventing the delayed bleeding after the removal of colon polyps is still controversial. In order to clarify this efficacy, a randomized controlled study was performed. METHODS: One hundred and fifty-six patients with colon neoplasms (288 lesions) were enrolled in the study. The patients were randomly divided into two groups: clipping or nonclipping groups using a sealed envelope method before the endoscopic resections. Eight specialists and nine residents were invited to perform this procedure. The risk factors and the rates of delayed bleeding after the endoscopic resections in each group were investigated. RESULTS: There were no significant differences in the bleeding rate between the clipping and nonclipping groups, while the length of the procedure was significantly longer and the cost was higher in the clipping group than in the nonclipping group. The rate of bleeding was significantly higher in cases with polyps 2 cm or larger and with a longer procedure time, while none of the other factors affected the bleeding rate. CONCLUSIONS: This randomized controlled study revealed no significant effect of prophylactic clipping for preventing delayed bleeding after the endoscopic resection of colon polyps.

A Bamboo Joint-Like Appearance is a Characteristic Finding in the Upper Gastrointestinal Tract of Crohn's Disease Patients: A Case-Control Study.

The clinical importance of Crohn's disease (CD)-specific lesions in the upper gastrointestinal tract (upper GIT) has not been sufficiently established. The aim of this case-control study is to investigate the characteristic findings of CD in the upper GIT. In 2740 patients who underwent gastroduodenoscopy at Asahikawa Medical University between April 2011 and December 2012, 81 CD patients, 81 gender- and age-matched non-IBD patients, and 66 ulcerative colitis (UC) patients were investigated in the present study. (1) The diagnostic ability and odds ratio of each endoscopic finding (a bamboo joint-like appearance in the cardia, erosions, and/or ulcers in the antrum, notched signs, and erosions and/or ulcers in the duodenum) were compared between the CD and non-IBD patients or UC patients. (2) The interobserver agreement of the diagnosis based on the endoscopic findings was evaluated by 3 experienced and 3 less-experienced endoscopists. The incidence of detecting a bamboo joint-like appearance, notched signs, and erosions and/or ulcers in the duodenum was significantly higher in the CD patients than in the non-IBD and UC patients. In addition, the diagnostic ability and odds ratio of a bamboo joint-like appearance for CD were higher than those for the other findings. Kendall's coefficients of concordance in the group of experienced and less-experienced endoscopists were relatively high for a bamboo joint-like appearance (0.748 and 0.692, respectively). A cardiac bamboo joint-like appearance is a useful finding for identifying high-risk groups of CD patients using only gastroduodenoscopy.

Infliximab extends the duration until the first surgery in patients with Crohn's disease.

BACKGROUND/AIMS: While biological drugs are useful for relieving the disease activity and preventing abdominal surgery in patients with Crohn's disease (CD), it is unclear whether the use of biological drugs in CD patients with no history of abdominal surgery is appropriate. We evaluated the effects of infliximab and other factors on extending the duration until the first surgery in CD patients on a long-term basis. METHODS: The clinical records of 104 CD patients were retrospectively investigated. The cumulative nonoperation rate until the first surgery was examined with regard to demographic factors and treatments. RESULTS: The 50% nonoperative interval in the 104 CD patients was 107 months. The results of a univariate analysis revealed that a female gender, the colitis type of CD, and the administration of corticosteroids, immunomodulators, or infliximab were factors estimated to improve the cumulative nonoperative rate. A multivariate analysis showed that the colitis type and administration of infliximab were independent factors associated with a prolonged interval until the first surgery in the CD patients with no history of abdominal surgery. CONCLUSIONS: This study suggests that infliximab treatment extends the duration until the first surgery in CD patients with no history of abdominal surgery. The early use of infliximab before a patient undergoes abdominal surgery is therefore appropriate.