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Featured researches published by Hiroya Ueyama.


The American Journal of Surgical Pathology | 2010

Gastric adenocarcinoma of fundic gland type (chief cell predominant type): proposal for a new entity of gastric adenocarcinoma.

Hiroya Ueyama; Takashi Yao; Yutaka Nakashima; Katsuya Hirakawa; Yumi Oshiro; Minako Hirahashi; Akinori Iwashita; Sumio Watanabe

Only a few cases of gastric adenocarcinoma of fundic gland type have been reported. Gastric adenocarcinoma with chief cell differentiation (GA-CCD) has been recently reported as a new variant of gastric adenocarcinoma. However, its clinicopathologic features are uncertain. To elucidate them, GA-CCDs exhibiting pepsinogen-I expression (10 lesions: Group A) and randomly selected gastric adenocarcinomas of differentiated type (111 lesions: Group B) were evaluated in this study. Cell differentiation by MUC2, MUC5AC, MUC6, CD10, pepsinogen-I, H+/K+-ATPase and chromogranin A, cell proliferation by Ki-67, and overexpression of p53 protein were evaluated immunohistochemically. In Group A, all GA-CCDs were located in the upper third of the stomach. Tumors were small, with the average maximum diameter ranging from 4 to 20 (average, 8.6) mm. Histologically, GA-CCDs were well-differentiated adenocarcinomas composed of pale gray-blue, basophilic columnar cells with mild nuclear atypia, resembling chief cells. Immunohistochemically, scattered positivity for H+/K+-ATPase was observed in addition to expression of pepsinogen-I and MUC6, indicating focal differentiation toward parietal cells. In Group B, pepsinogen-I was very focally expressed in 2 cases. As these 2 cases exhibited different clinicopathological and histologic features, they cannot be categorized as GA-CCD. Mild atypism, no lymphovascular invasion, low proliferative activity, no overexpression of p53, and no recurrence indicated less aggressiveness of GA-CCD. GA-CCD is rare, but it has distinct clinicopathological characteristics, especially in terms of tumor location, histologic features, phenotypic expression, and low-grade malignancy. We propose gastric adenocarcinoma of fundic gland type (chief cell predominant type) as a new entity of gastric adenocarcinoma.


Endoscopy | 2013

Gastric adenocarcinoma of the fundic gland type (chief cell predominant type).

Hiroya Ueyama; Kenshi Matsumoto; Akihito Nagahara; Takuo Hayashi; Takashi Yao; Sumio Watanabe

Gastric adenocarcinoma of the fundic gland (chief cell predominant type, GA-FG-CCP) was recently proposed as a new, rare variant of gastric adenocarcinoma. The aim of the current study was to evaluate the endoscopic features of GA-FG-CCP. A total of 10 GA-FG-CCPs were included and evaluated retrospectively. The endoscopic and clinicopathological features of the lesions were analyzed to provide information of diagnostic value. The GA-FG-CCPs were classified into two categories: submucosal tumor shape (60 %) and flat or depressed type (40 %). Endoscopically, the most common features were submucosal tumor shape (60 %), whitish color (70 %), dilated vessels with branching architecture (50 %), and background mucosa without atrophic change (90 %). GA-FG-CCP has distinct endoscopic characteristics, especially in terms of shape, color, vessels, and background mucosa and may be classified into two categories macroscopically. To diagnose GA-FG-CCP correctly by pathological examination of biopsy specimens, these endoscopic features should be taken into consideration.


Gastroenterology Research and Practice | 2016

Procedure Time for Gastric Endoscopic Submucosal Dissection according to Location, considering Both Mucosal Circumferential Incision and Submucosal Dissection

Hironori Konuma; Kenshi Matsumoto; Hiroya Ueyama; Hiroyuki Komori; Yoichi Akazawa; Misuzu Ueyama; Yuta Nakagawa; Takashi Morimoto; Tsutomu Takeda; Kohei Matsumoto; Daisuke Asaoka; Mariko Hojo; Akihito Nagahara; Takashi Yao; Akihisa Miyazaki; Sumio Watanabe

Background. Previous assessments of technical difficulty and procedure time for endoscopic submucosal dissection (ESD) of gastric neoplasms did not take into account several critical determinants of these parameters. However, two key phases of ESD determine the total procedure time: the mucosal circumference incision speed (CIS) and submucosal dissection speed (SDS). Methods. We included 302 cases of en bloc and R0 resection of gastric neoplasms performed by 10 operators who had completed the training program at our hospital. Twelve locations were classified based on multiple criteria, such as condition of surrounding mucosa, lesion vascularity, presence of submucosal fat, ulcers, scars, fibrosis, and scope and device maneuverability. Lesions in different locations were classified into three groups based on the length of the procedure: fast, moderate, or late. Results. A significant difference was found in CIS and SDS for each location (p < 0.01), which demonstrates the validity of this classification system. In several locations, CIS and SDS were not consistent with each other. Conclusion. CIS and SDS did not correspond to each other even for lesions in the same location. Consideration of ESD procedure time for gastric neoplasms requires a more elaborate classification system than that previously reported.


World Journal of Gastroenterology | 2013

A white opaque substance-positive gastric hyperplastic polyp with dysplasia

Hiroya Ueyama; Kenshi Matsumoto; Akihito Nagahara; Ryosuke Gushima; Takuo Hayashi; Takashi Yao; Sumio Watanabe

The endoscopic findings of gastric hyperplastic polyps (HPs) with dysplasia have not been well-defined, and the clinical significance of these lesions, including their malignant potential, is unclear. In this report, we describe a case of a white opaque substance (WOS)-positive gastric HP with dysplasia. A 76-year-old woman was referred to our hospital for endoscopic resection of a gastric HP. Upper endoscopy revealed a 25-mm whitish and reddish polypoid lesion on the greater curvature in the lower third of the stomach. The whitish part was diagnosed as a WOS using conventional and magnifying endoscopy with narrow band imaging. An examination of the biopsy specimen indicated that the lesion was a typical gastric HP. However, because of its color and the presence of a WOS, we suspected that this lesion was an atypical gastric HP. Therefore, we performed a polypectomy. Histopathologically, diffuse low- to high-grade dysplasia was found on the surface of the polyp. We performed immunohistochemical staining using a monoclonal antibody specific for adipophilin as a marker of lipid droplets (LDs). LDs were detected in approximately all of the neoplastic cells, especially in the surface epithelium of the intervening apical parts and were located in the subnuclear cytoplasm of the neoplastic cells. According to endoscopic and histopathological findings, the WOS-positive epithelium indicated dysplasia of the gastrointestinal phenotype, which could absorb lipids. The presence of a WOS in a gastric HP may be considered an endoscopic finding that is predictive of the neoplastic transformation of a gastric HP. We suggest that a WOS-positive gastric HP should be resected endoscopically to investigate its neoplastic transformation.


Therapeutics and Clinical Risk Management | 2015

Risk factors for osteoporosis in Japan: is it associated with Helicobacter pylori ?

Daisuke Asaoka; Akihito Nagahara; Yuji Shimada; Kenshi Matsumoto; Hiroya Ueyama; Kohei Matsumoto; Yuta Nakagawa; Tsutomu Takeda; Ippei Tanaka; Hitoshi Sasaki; Taro Osada; Mariko Hojo; Sumio Watanabe

Background A number of diseases and drugs may influence bone mineral density; however, there are few reports concerning the relationship between lifestyle-related diseases and osteoporosis in Japan as determined by multivariate analysis. The aim of this study was to investigate the risk factors for osteoporosis and whether infection by or eradication of Helicobacter pylori is associated with osteoporosis. Methods Between February 2008 and November 2014, using a cross-sectional study design, we investigated patient profile (age, sex, BMI, alcohol, smoking), H. pylori infection status, comorbidities, internal medicine therapeutic agents (calcium channel blocker, HMG-CoA reductase inhibitors, proton pump inhibitor), serum parameters (Hb, calcium, γGTP), bone turn over markers (bone-specific alkaline phosphatase (BAP) and collagen type I cross-linked N telopeptide (NTX), findings on dual-energy x-ray absorptiometry (DEXA) and upper gastrointestinal endoscopy, and Frequency Scale for the Symptoms of GERD score in consecutive outpatients aged ≥50 years at our hospital. We divided the subjects into an osteoporosis group and a non-osteoporosis group and investigated risk factors for osteoporosis between the two groups by bivariate and multivariate analyses. Results Of the 255 eligible study subjects, 43 (16.9%) had osteoporosis. Bivariate analysis showed that advanced age, female sex, lower body mass index, lower cumulative alcohol intake, lower Brinkman index, H. pylori positivity, lower hemoglobin, bone-specific alkaline phosphatase, lower prevalence of hiatal hernia, and endoscopic gastric mucosal atrophy were related to osteoporosis. Multivariate analysis showed that advanced age (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.07–1.19, P<0.001), female sex (OR 6.27, 95% CI 2.26–17.39, P<0.001), low BMI (OR 0.82, 95% CI 0.72–0.94, P=0.005), H. pylori positivity (OR 3.00, 95% CI 1.31–6.88, P=0.009), and BAP (OR 1.07, 95% CI 1.01–1.14, P=0.035) were related to osteoporosis. Conclusion Advanced age, low BMI, BAP, and H. pylori positivity were risk factors for osteoporosis; however, the success of H. pylori eradication was not a risk factor for osteoporosis in Japan.


World Journal of Gastrointestinal Endoscopy | 2011

Mallory-Weiss tear during gastric endoscopic submucosal dissection

Hiroki Hongou; Kuangi Fu; Hiroya Ueyama; Taiji Takahashi; Tsutomu Takeda; Akihisa Miyazaki; Sumio Watanabe

A 78-year-old woman was referred to our department for treatment of an early gastric cancer. Esophagogastroduodenoscopy (EGD) demonstrated a flat elevated lesion and a polypoid lesion on the greater curvature of the antrum. Histological analysis of, endoscopic biopsy samples taken from these lesions revealed an adenocarcinoma and a hyperplastic polyp, respectively. ESD was conducted for removal of the lesions. Carbon dioxide (CO(2)) instead of room air was used for insufflation, and the patient was adequately sedated without struggling or vomiting during the treatment. No significant bleeding from the lesion was observed during ESD, but fresh blood was identified endoscopically. Surprisingly, a Mallory-Weiss tear with active bleeding was detected on the lesser curvature of the gastric corpus. A total of eight hemoclips were applied for hemostasis. Both lesions were completely removed en bloc, and no bleeding or perforation developed after ESD. Histologically, the first lesion was a papillary carcinoma limited to the mucosal layer and without lymphovascular invasion or involvement of the surgical margins, while the second lesion was a benign hyperplastic polyp.


World Journal of Gastroenterology | 2016

Clinicopathological features of alpha-fetoprotein producing early gastric cancer with enteroblastic differentiation

Kohei Matsumoto; Hiroya Ueyama; Kenshi Matsumoto; Yoichi Akazawa; Hiroyuki Komori; Tsutomu Takeda; Takashi Murakami; Daisuke Asaoka; Mariko Hojo; Natsumi Tomita; Akihito Nagahara; Yoshiaki Kajiyama; Takashi Yao; Sumio Watanabe

AIM To investigate clinicopathological features of early stage gastric cancer with enteroblastic differentiation (GCED). METHODS We retrospectively investigated data on 6 cases of early stage GCED and 186 cases of early stage conventional gastric cancer (CGC: well or moderately differentiated adenocarcinoma) who underwent endoscopic submucosal dissection or endoscopic mucosal resection from September 2011 to February 2015 in our hospital. GCED was defined as a tumor having a primitive intestine-like structure composed of cuboidal or columnar cells with clear cytoplasm and immunohistochemical positivity for either alpha-fetoprotein, Glypican 3 or SALL4. The following were compared between GCED and CGC: age, gender, location and size of tumor, macroscopic type, ulceration, depth of invasion, lymphatic and venous invasion, positive horizontal and vertical margin, curative resection rate. RESULTS Six cases (5 males, 1 female; mean age 75.7 years; 6 lesions) of early gastric cancer with a GCED component and 186 cases (139 males, 47 females; mean age 72.7 years; 209 lesions) of early stage CGC were investigated. Mean tumor diameters were similar but rates of submucosal invasion, lymphatic invasion, venous invasion, and non-curative resection were higher in GCED than CGC (66.6% vs 11.4%, 33.3% vs 2.3%, 66.6% vs 0.4%, 83.3% vs 11% respectively, P < 0.01). Deep submucosal invasion was not revealed endoscopically or by preoperative biopsy. Histologically, in GCED the superficial mucosal layer was covered with a CGC component. The GCED component tended to exist in the deeper part of the mucosa to the submucosa by lymphatic and/or venous invasion, without severe stromal reaction. In addition, Glypican 3 was the most sensitive marker for GCED (positivity, 83.3%), immunohistochemically. CONCLUSION Even in the early stage GCED has high malignant potential, and preoperative diagnosis is considered difficult. Endoscopists and pathologists should know the clinicopathological features of this highly malignant type of cancer.


Gastrointestinal Endoscopy | 2013

Process of wound healing of large mucosal defect areas that were sutured by using a loop clip–assisted closure technique after endoscopic submucosal dissection of a colorectal tumor

Taro Osada; Naoto Sakamoto; Hideaki Ritsuno; Takashi Murakami; Hiroya Ueyama; Tomoyoshi Shibuya; Kenshi Matsumoto; Akihito Nagahara; Tatsuo Ogihara; Sumio Watanabe

3. van Boeckel PG, Dua KS, Weusten BL, et al. Fully covered self-expandable metal stents (SEMS), partially covered SEMS and self-expandable plastic stents for the treatment of benign esophageal ruptures and anastomotic leaks. BMC Gastroenterol 2012;12:19. 4. van Boeckel PG, Sijbring A, Vleggaar FP, et al. Systematic review: temporary stent placement for benign rupture or anastomotic leak of the oesophagus. Aliment Pharmacol Therap 2011;33:1292-301. 5. van Heel NC, Haringsma J, Spaander MC, et al. Short-term esophageal stenting in the management of benign perforations. Am J Gastroenterol 2010;105:1515-20. 6. Dan DT, Gannavarapu B, Lee JG, et al. Removable esophageal stents have poor efficacy for the treatment of refractory benign esophageal strictures (RBES). Dis Esophagus. Epub 2012 Nov 2.


Biomedical Reports | 2017

Efficacy of a potassium‑competitive acid blocker for improving symptoms in patients with reflux esophagitis, non‑erosive reflux disease, and functional dyspepsia

Daisuke Asaoka; Akihito Nagahara; Mariko Hojo; Kenshi Matsumoto; Hiroya Ueyama; Kohei Matsumoto; Kentaro Izumi; Tsutomu Takeda; Hiroyuki Komori; Yoichi Akazawa; Yuji Shimada; Taro Osada; Sumio Watanabe

The aim of the present study was to investigate the efficacy of a potassium-competitive acid blocker (PCAB) named vonoprazan (VPZ) for improving symptoms in patients with reflux esophagitis (RE), non-erosive reflux disease (NERD), and functional dyspepsia (FD). A hospital-based, retrospective study of outpatients in our department (Department of Gastroenterology, University of Juntendo, Tokyo, Japan) between March 2015 and August 2016 was performed. The patients who were experiencing heartburn, acid regurgitation, gastric pain, and/or a heavy feeling in the stomach of at least moderate severity at baseline were treated with 20 mg VPZ once daily for 4 weeks. The patients completed the global overall symptom (GOS) scale to determine their symptom severity at baseline and after the 4 week treatment period. The proportions of patients with RE, NERD, and FD achieving improvement of their symptoms, defined as a GOS scale score of 1 (‘no problem’) or 2 (‘minimal problem’), were evaluated. During 4 weeks of VPZ therapy, changes in the gastroesophageal reflux disease (GERD) score, which was defined as the total points for heartburn and acid regurgitation on the GOS scale in patients with RE and NERD, and in the FD score, which was defined as the total points for gastric pain and a heavy feeling in the stomach on the GOS scale in patients with FD, were also evaluated. A total of 88 eligible cases were included in the present study, comprising 20 patients with RE, 25 patients with NERD, and 43 patients with FD. The rates of symptomatic improvement in patients with RE, NERD, and FD were 75.0, 60.0, and 48.8%, respectively. For the patients who were first administered VPZ, the rates of symptomatic improvement were 90.9, 66.7, and 58.8% in patients with RE, NERD, and FD, respectively. For those patients who were resistant to 8 weeks of proton pump inhibitor therapy, the rates of symptomatic improvement were 55.6, 53.8, and 42.3% in patients with RE, NERD, and FD, respectively. The GERD score in patients with RE and NERD, and the FD score in FD patients, were decreased after 4 weeks of VPZ therapy (P<0.01). In patients with RE, NERD and FD, the possibility that PCAB may be used as a novel therapeutic drug was suggested. However, the number of study subjects was small; therefore, further, larger and prospective studies are required.


Therapeutics and Clinical Risk Management | 2016

Association of medications for lifestyle-related diseases with reflux esophagitis.

Daisuke Asaoka; Akihito Nagahara; Mariko Hojo; Kenshi Matsumoto; Hiroya Ueyama; Kohei Matsumoto; Kentaro Izumi; Tsutomu Takeda; Hiroyuki Komori; Yoichi Akazawa; Yuji Shimada; Taro Osada; Sumio Watanabe

Background Because of a change in lifestyle, especially adoption of westernized eating habits, lifestyle-related diseases have become increasingly prevalent. The aim of this study was to investigate the association of medications for lifestyle-related diseases with reflux esophagitis (RE). Methods We conducted a hospital-based, cross-sectional retrospective study of consecutive outpatients who received an upper gastrointestinal endoscopy in our department from February 2008 to November 2014, which was performed by one specialist who was a member of the Japan Gastroenterological Endoscopy Society. We investigated the patient profile, Helicobacter pylori (H. pylori) infection status, medications for lifestyle-related diseases (including calcium channel blockers, statins, and bisphosphonates), and upper gastrointestinal endoscopic findings (RE, hiatal hernia, Barrett’s mucosa, and endoscopic gastric mucosal atrophy [EGA]). Patients with gastrectomy, peptic ulcer disease, gastric or esophageal malignant disease, and those who used proton pump inhibitors or histamine-2 receptor antagonists were excluded. We divided the subjects into a group without RE (RE(−)) and a RE (RE(+)) group as judged by endoscopy, and investigated the risk factors for RE. Results Of 1,744 consecutive cases, 590 cases (300 males and 290 females; mean age 60.5±13.2 years) were eligible. RE(−) and RE(+) cases numbered 507 and 83, respectively. Bivariate analysis showed significant positive associations of RE with male sex, body mass index (BMI), calcium channel blockers, Barrett’s mucosa, hiatal hernia and negative associations of RE with H. pylori positivity, EGA. Multivariate analysis showed significant positive associations of RE with BMI (odds ratio [OR]: 1.20, 95% confidence interval [95% CI]: 1.10–1.29), use of calcium channel blockers (OR: 2.12, 95% CI: 1.16–3.87), Barrett’s mucosa (OR: 2.97, 95% CI: 01.64–5.38), hiatal hernia (OR: 3.13, 95% CI: 1.79–5.47) and negative associations of RE with H. pylori positivity (OR: 0.20, 95% CI: 0.07–0.57), use of statins (OR: 0.42, 95% CI: 0.18–0.96), and EGA (OR: 0.83, 95% CI: 0.70–0.98). Conclusion Calcium channel blockers were positively associated with RE and statins were negatively associated with RE, while bisphosphonates were not associated with RE.

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