[Traumatic Neuroma Mimicking Lymph Node Metastasis of Pancreatic Neuroendocrine Neoplasms Developed after Pancreatoduodenectomy-A Case Report].

A traumatic neuroma is a benign tumor consisting of a non-neoplastic growth of injured nerves as a result of trauma or surgery. It is rarely found in an abdominal cavity, but some reports showed that it occurred around the bile duct. We report a case of a 72-year-old man who underwent subtotal stomach-preserving pancreatoduodenectomy for pancreatic neuroendocrine neoplasms 4 years ago. An abdominal contrast-enhanced CT follow-up examination revealed a growing nodule on the dorsal surface of the portal vein. The lesion showed a mild increase in fluorodeoxyglucose uptake in FDG-PET⊘CT. A lymph node metastasis of pancreatic neuroendocrine neoplasms was suspected. Nodule resection was performed for purpose of diagnosis and treatment. The final pathological diagnosis was traumatic neuroma with no evidence of recurrence. Traumatic neuromas developed after pancreatoduodenectomy have not been reported. Postoperative masses around the bile ducts should also be considered traumatic neuromas.

[A case of rectovaginal metastasis 6 years after initial resection of extra-gastrointestinal stromal tumor of vulvar origin].

A 53-year-old woman who had undergone excision of KIT-positive extra-gastrointestinal stromal tumor (EGIST) of the vulva 6 years ago presented to our hospital due to a positive fecal occult blood test. Colonoscopy revealed a submucosal tumor in the rectum ventral side. In addition, computed tomography and magnetic resonance imaging revealed a tumor in the rectovaginal septum. For diagnostic and therapeutic purposes, the tumor was resected via the perineal approach. The resected specimen analysis revealed a KIT-positive gastrointestinal stromal tumor (GIST). Following immunopathological and genetic mutation identifications, GIST of the rectovaginal septum from vulva EGIST metastasis was diagnosed. It is important to consider primary GIST and metastatic GIST as differential diagnoses in the case of a rectal submucosal tumor detected by endoscopy.

[Hematemesis due to rupture of splenic artery pseudoaneurysm in association with segmental arterial mediolysis:a case report].

A gastric ulcer was detected in a 54-year-old man who underwent upper gastrointestinal endoscopy for hematemesis. An abdominal contrasted computed tomography scan detected a splenic artery aneurysm adjacent to the gastric wall. Endoscopic hemostasis was thought to be risky owing to possible rupture of the aneurysm. Rupture of a splenic artery pseudoaneurysm due to segmental arterial mediolysis (SAM) was diagnosed by abdominal angiography, and subsequently transcatheter arterial embolization was performed. In cases of upper gastrointestinal hemorrhage, hemostasis is often performed during the emergency endoscopic examination. However, in cases of massive gastrointestinal bleeding, the possibility of a splenic artery aneurysm, in association with SAM, should be recognized. The risk of rupturing the aneurysm should be considered in selecting the most suitable treatment.

[Intraductal papillary neoplasm of bile duct developed in a patient with IgG4-related sclerosing cholangitis, autoimmune pancreatitis, and myasthenia gravis].

In the course of treatment for myasthenia gravis, enlargement of a cystic mass in the liver with peripheral bile duct dilation, diffuse pancreatic enlargement, and serum IgG4 level elevation was identified in a 65-year-old man. Following the diagnosis of autoimmune pancreatitis, a left hepatectomy was performed because of suspected malignancy of the cystic lesion. Analysis of the resected specimen revealed the cystic lesion to be a dilated bile duct. Intraductal papillary tumor comprising fibrovascular stalks covered by neoplastic epithelium was identified in the lesion. Infiltration of IgG4-positive plasma cells was discovered around the cystic lesion. Finally, a diagnosis of intraductal papillary neoplasm of bile duct with IgG4-related sclerosing cholangitis was made. Autoimmune diseases, including IgG4-related diseases, require careful observation because of their potential for malignancy.

[Successful resection of a gastric aberrant pancreas causing gastrointestinal bleeding by laparoscopy and endoscopy cooperative surgery].

A man in his 50s was admitted to our hospital for treatment of hematemesis. Endoscopy revealed arterial bleeding from a gastric submucosal tumor and endoscopic hemostasis was successful. However, surgical resection was contemplated to prevent recurrent bleeding and for making a definitive diagnosis. Surgical resection was eventually performed by laparoscopy and endoscopy cooperative surgery (LECS), and the tumor was pathologically diagnosed to be a gastric aberrant pancreas. We think that LECS is suitable for a gastric aberrant pancreas causing gastrointestinal bleeding, because the procedure is effective for tumor resection with minimal removal of the stomach wall.

Mice deficient in protein tyrosine phosphatase receptor type Z are resistant to gastric ulcer induction by VacA of Helicobacter pylori.

The vacuolating cytotoxin VacA produced by Helicobacter pylori causes massive cellular vacuolation in vitro and gastric tissue damage in vivo, leading to gastric ulcers, when administered intragastrically. Here we report that mice deficient in protein tyrosine phosphatase receptor type Z (Ptprz, also called PTP-zeta or RPTP-beta, encoded by Ptprz) do not show mucosal damage by VacA, although VacA is incorporated into the gastric epithelial cells to the same extent as in wild-type mice. Primary cultures of gastric epithelial cells from Ptprz+/+ and Ptprz-/- mice also showed similar incorporation of VacA, cellular vacuolation and reduction in cellular proliferation, but only Ptprz+/+ cells showed marked detachment from a reconstituted basement membrane 24 h after treatment with VacA. VacA bound to Ptprz, and the levels of tyrosine phosphorylation of the G protein-coupled receptor kinase-interactor 1 (Git1), a Ptprz substrate, were higher after treatment with VacA, indicating that VacA behaves as a ligand for Ptprz. Furthermore, pleiotrophin (PTN), an endogenous ligand of Ptprz, also induced gastritis specifically in Ptprz+/+ mice when administered orally. Taken together, these data indicate that erroneous Ptprz signaling induces gastric ulcers.

A novel fully covered metal stent for unresectable malignant distal biliary obstruction: results of a multicenter prospective study.

Background/Aims: Endoscopic self-expandable metal stent (SEMS) placement is currently the standard technique for treating unresectable malignant distal biliary obstructions (MDBO). Therefore, covered SEMS with longer stent patency and fewer migrations are required. This study aimed to assess the clinical performance of a novel, fully covered SEMS for unresectable MDBO. Methods: This was a multicenter single-arm prospective study. The primary outcome was a non-obstruction rate at 6 months. The secondary outcomes were overall survival (OS), recurrent biliary obstruction (RBO), time to RBO (TRBO), technical and clinical success, and adverse events. Results: A total of 73 patients were enrolled in this study. The non-obstruction rate at 6 months was 61%. The median OS and TRBO were 233 and 216 days, respectively. The technical and clinical success rates were 100% and 97%, respectively. Furthermore, the rate of occurrence of RBO and adverse events was 49% and 21%, respectively. The length of bile duct stenosis (<2.2 cm) was the only significant risk factor for stent migration. Conclusions: The non-obstruction rate of a novel fully covered SEMS for MDBO is comparable to that reported earlier but shorter than expected. Short bile duct stenosis is a significant risk factor for stent migration.

Association of CD4-positive cell infiltration with response to vedolizumab in patients with ulcerative colitis.

Not all patients with ulcerative colitis (UC) respond initially to treatment with biologic agents, and predicting their efficacy prior to treatment is difficult. Vedolizumab, a humanized monoclonal antibody against alpha 4 beta 7 (α4ß7) integrin, suppresses immune cell migration by blocking the interaction between α4ß7 integrin and mucosal addressin cell adhesion molecule 1. Reports about histological features that predict vedolizumab efficacy are scarce. So, we examined the association between histological features and vedolizumab efficacy. This was a multicenter, retrospective study of patients with UC treated with vedolizumab. Biopsy specimens taken from the colonic mucosa prior to vedolizumab induction were used, and the areas positively stained for CD4, CD68, and CD45 were calculated. Clinical and histological features were compared between those with and without remission at week 22, and the factors associated with clinical outcomes were identified. We enrolled 42 patients. Patients with a high CD4+ infiltration showed a better response to vedolizumab [odds ratio (OR) = 1.44, P = 0.014]. The concomitant use of corticosteroids and high Mayo scores had a negative association with the vedolizumab response (OR = 0.11, P = 0.008 and OR = 0.50, P = 0.009, respectively). Histological evaluation for CD4+ cell infiltration may be helpful in selecting patients who can benefit from vedolizumab.

Observation of gastro-esophageal reflux by MRI: a feasibility study.

PURPOSE: To evaluate the feasibility of detecting and measuring gastro-esophageal reflux (GER) with esophageal MR fluoroscopy in patients suffering from heartburn. MATERIALS AND METHODS: Twenty patients with heartburn underwent esophageal MR fluoroscopy. The T1-FFE sequence was applied for MR imaging. We examined the frequency and the level of GER on MR images. Based on the MRI observations, patients were classified into four MRI grades (grade 1-4). Endoscopic findings were categorized into five grades (grade 0 to D). The overall MRI grade, Carlsson's questionnaire score, and endoscopic findings were compared. RESULTS: GER was observed with MR fluoroscopy in 19 of 20 patients. GER was observed only several times in three patients, and much more frequently in the remaining 16 patients. Elevated levels of GER reached the lower, middle-to-upper esophagus, and the hypopharynx. The observed MRI grades were grade 1 = 1 patient, grade 2 = 3 patients, grade 3 = 2 patients, and grade 4 = 13 patients. There was no statistical correlation between the questionnaire score and the MRI grade. Also, there was no correlation between the grade of endoscopic findings and MRI grade. Six patients demonstrated continuous reflux on MRI did not show mucosal injury at endoscopy. CONCLUSION: Esophageal MR fluoroscopy may be a useful diagnostic tool for GERD for its ability to show GER, even in patients with no mucosal injury, and for suggesting the cause of the reflux.

Superficially elevated-type serrated hyperplastic lesion of the stomach with minute adenocarcinoma.

We report a case of gastric serrated hyperplastic lesion with minute adenocarcinoma. A 65-year-old Japanese man underwent endoscopic submucosal dissection to the superficially elevated-type (0-IIa) lesion located at the lesser curvature of the gastric angle. Histological observation revealed hyperplastic change of foveolar epithelium with serrated glandular structure as well as a minute tubular adenocarcinoma component. Immunohistochemically, the lesion demonstrated gastrointestinal, predominantly gastric, phenotype (MUC5AC++, MUC6+, MUC2+, CD10-). Positive p53 immunoreactivity was detected in the carcinoma component of the lesion with a point mutation (G877T; R209I) of the gene and microsatellite instability of the BAT-RII locus; however, immunoreactivity of the mismatch repair gene product hMLH1 was well preserved in the cancer as well as in the hyperplastic lesion. The hyperplastic lesion with serrated glandular pattern would be a precancerous lesion of adenocarcinoma of the stomach.

Role of metallothionein in Helicobacter pylori-positive gastric mucosa with or without early gastric cancer and the effect on its expression after eradication therapy.

BACKGROUND AND AIM: Metallothionein (MT) has a proven relationship with various kinds of cancer and reduces tissue damage. Helicobacter pylori (H. pylori) infection is associated with the alteration of gastric epithelial cell cycle events, a condition implicated in the initiation and development of gastric cancer. This study investigates the role of MT in H. pylori-induced gastritis with or without early gastric cancer (ECG) and evaluates the effect on MT expression after eradication therapy. METHODS: Gastric biopsy samples were immunohistochemically examined for MT expression in 36 H. pylori-negative patients without ECG and 98 positive patients with or without ECG. Real time polymerase chain reaction was performed in 14 antral biopsy samples with or without H. pylori. The severity of gastritis was also evaluated according to the updated Sydney System. In 31 successfully eradicated patients, the above assessment was repeated for two consecutive years. RESULTS: MT expression was higher in H. pylori-negative patients than in positive patients (P < 0.01). Moreover, in the corpus it was higher in H. pylori-positive patients without ECG compared to those with ECG (P < 0.05). The MT labeling index had a negative correlation with the severity of gastritis (P < 0.01). A positive correlation was shown between the MT labeling index and apoptosis: proliferation ratio (r = 0.41, P < 0.01). The MT labeling index in H. pylori-positive patients was gradually recovered after eradication (P < 0.05). CONCLUSION: The decrease of MT expression cannot prevent tissue damage in H. pylori-positive gastric mucosa and leads to more severe gastritis. This phenomenon may be attributed to gastric carcinogenesis. H. pylori eradication increases MT expression and may reduce the risk of ECG.

The relationship between gastric emptying determined by the breath test and H. pylori.

BACKGROUND/AIMS: Helicobacter pylori infection has been implicated in atrophic gastritis and gastric ulcer disease. However, the relationship between gastric emptying and Helicobacter pylori infection is still unclear. METHODOLOGY: One hundred and two consecutive patients with functional dyspepsia were enrolled in this study (53 Helicobacter pylori positive and 49 negative). Gastric emptying was determined using both the 13C-octanoic acid breath test and the paracetamol absorption test. For grading gastric atrophy, the biopsy samples and serum pepsinogen I/II ratio were used. The relationship between gastric emptying, Helicobacter pylori infection and atrophy grade was investigated. RESULTS: There was no significant difference in all gastric emptying parameters between Helicobacter pylori positive and negative patients. However, in Helicobacter pylori positive subjects, pepsinogen I/II ratio correlated with atrophy grade, and it also correlated with all parameters of gastric emptying. Especially in the half-emptying time, an important parameter, there was significant correlation with the pepsinogen I/II ratio (R = -0.39, p < 0.01). This finding implies that gastric emptying is delayed according to the degree of gastric atrophy. CONCLUSIONS: Gastric emptying was not delayed simply according to advanced age, but according to the advance in gastric atrophy.

Helicobacter pylori VacA and gastric ulcer.

VacA, the only protein toxin produced by Helicobacter pylori, vacuolates cultured cells. The presence of 2 VacA receptors has been demonstrated. One is the receptor-type protein tyrosine phosphatase (RPTP) zeta/beta (PTP zeta/beta), and the other is RPTP alpha. VacA binds to PTP zeta/beta, resulting in gastric epithelial detachment through the tyrosine phosphorylation of Git-1, which then leads to gastric ulceration by the direct action of gastric acid. Thus, disturbance of adhesion between gastric epithelial cells and the extracellular matrix due to an abnormal PTP zeta/beta signal is the main mechanism of gastric ulceration.

[A case of unknown primary cancer responding to TS-1].

A 65-year-old male showed elevated tumor marker and intra-abdominal lymph node (LN) swelling. PET revealed an accumulation of FDG at para-aortic LNs from the mediastinum to the inguinal region. Although many different examinations were performed to detect primary cancer, none was found. We diagnosed unknown primary cancer (UPC), and administered TS-1 (100 mg/day). Six months later, the tumor marker lowered and the LN swelling reduced. PET showed a little accumulation of FDG at intra-abdominal LN. An intra-abdominal LN biopsy was performed, and an adenocarcinoma was seen at a lymph vessel. Then, 15 months later, brain metastasis was recognized and 18 months later the patient died of systematic metastasis. Autopsy was not performed, and primary cancer was not seen till the end. TS-1 proved effective for the UPC.

Influence of gastritis on cyclooxygenase-2 expression before and after eradication of Helicobacter pylori infection.

OBJECTIVES: Helicobacter pylori infection causes chronic gastritis and induces cyclooxygenase (COX)-2 expression. The relationship between gastritis and COX-2 expression is not well understood, especially long after the organism has been eradicated. We designed a study to elucidate this relationship. METHODS: Four endoscopic gastric biopsies from each of 118 H. pylori-infected subjects were assessed for COX-2 expression immunohistochemically, gastritis, by an updated Sydney System. In the 107 successfully eradicated subjects, the assessment was repeated once yearly, for 3 years. RESULTS: After successful eradication, COX-2 expression was reduced significantly regardless of site. Atrophy improved significantly and intestinal metaplasia improved but not in the antrum greater curvature. After 1 year COX-2 expression was not significantly different in the epithelia with and without intestinal metaplasia. Correlation between COX-2 expression and neutrophil score in the antrum (r = 0.214, P = 0.042) and inflammation in the corpus (r = 0.234, P = 0.025) disappeared after eradication. COX-2 expression correlated well with atrophy and metaplasia before and after eradication. No significant reduction in COX-2 or improvement in gastritis was found in subjects with eradication failure. CONCLUSION: H. pylori infection is associated with the enhancement of COX-2 expression in the gastric mucosa. Eradication therapy reduces COX-2 expression and hence may reduce the risk of cancer development.

Impact of clarithromycin resistance and CYP2C19 genetic polymorphism on treatment efficacy of Helicobacter pylori infection with lansoprazole- or rabeprazole-based triple therapy in Japan.

OBJECTIVE: Helicobacter pylori treatment failure is thought to be due mainly to polymorphic cytochrome P450 2C19 (CPY2C19) genetic polymorphism, associated with proton pump inhibitor metabolism, and antimicrobial susceptibility. This report has ascertained which was more important, CPY2C19 polymorphism or antimicrobial susceptibility, when using 1-week lansoprazole-based or rabeprazole-based triple therapy in Japan. DESIGN: An open, randomized, parallel group study. SETTING: One hundred and forty-five subjects with H. pylori-positive gastritis or peptic ulcers were randomly assigned to receive 30 mg lansoprazole twice daily (LAC group), 10 mg rabeprazole twice daily (RAC20 group), or 20 mg rabeprazole twice daily (RAC40 group), with 1000 mg amoxicillin twice daily and 400 mg clarithromycin twice daily for 1 week. Antimicrobial resistance testing was performed by E-test. More than 4 weeks after completion of treatment, H. pylori status was assessed by 13C-urea breath test, histology, and culture. RESULTS: Cure rates expressed as intention-to-treat and per-protocol analyses, respectively, were 79.6 and 83.0% with LAC, 85.4 and 89.1% with RAC20, and 83.3 and 88.9% with RAC40. In the case of clarithromycin-sensitive strains, the cure rates were more than 97%, regardless of CPY2C19 polymorphism. However, treatment succeeded in only one out of 16 clarithromycin-resistant strains. CONCLUSIONS: The key to successful eradication of H. pylori, using lansoprazole or rabeprazole with clarithromycin and amoxicillin, is clarithromycin susceptibility, not CPY2C19 polymorphism.

[Progress of tailor-made treatment of peptic ulcer].

We previously reported that a comparative pharmacokinetic study with each PPI was designed as an open, randomized, and crossover study of 18 Japanese healthy volunteers who were classified into the homozygous, heterozygous extensive metabolizer and the poor metabolizer based on the CYP2C19 genotype. With at least 1 week washout period between treatments. Plasma concentrations of PPIs and their metabolites were monitored until 12 h after medication. Pharmacokinetic profiles of omeprazole and lansoprazole were well correlated with the CYP2C19 genotype. The heterozygous extensive metabolizer was slightly different from the homozygote, but there was no statistically significant difference. The CYP2C19 genotype dependence found for lansoprazole was not obvious compared with omeprazole. As for rabeprazole, the pharmacokinetic profile was independent of the CYP2C19 genotype. CYP2C19 genotyping can provide a new strategy to choose an optimal regimen, and this genotyping is especially useful for Japanese, as the frequency of poor metabolizers is five times greater than that found among Caucasians.

[Tailor-made medicine in Helicobacter pylori eradication therapy].

Pharmacokinetic profiles of omeprazole and lansoprazole were well correlated with the CYP2C19 genotype. The heterozygous extensive metabolizer was slightly different from the homozygote, but there was no statistically significant difference. The CYP2C19 genotype dependence found for lansoprazole was not obvious compared with omeprazole. As for rabeprazole, the pharmacokinetic profile was independent of the CYP2C19 genotype. CYP2C19 genotyping can provide a new strategy to choose an optimal regimen, and this genotyping is especially useful for Japanese, as the frequency of poor metabolizers is five times greater than that found among Caucasians. However, we should be aware that the increase of antimicrobial-resistant strains of H. pylori may force us to examine antimicrobial susceptibility of all patients in order to achieve a more than 80% eradication rate at first-line therapy in the near future. We should also have proper knowledge of the influence of the CYP2C19 genetic polymorphism on treatment efficacy according to the variety of PPI and the combination with other drugs.