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Dive into the research topics where Takao Tsuzuki is active.

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Featured researches published by Takao Tsuzuki.


Gastrointestinal Endoscopy | 2008

Risk factors associated with local recurrence of early gastric cancers after endoscopic submucosal dissection

Ryuta Takenaka; Yoshiro Kawahara; Hiroyuki Okada; Keisuke Hori; Masafumi Inoue; Seiji Kawano; Daisuke Tanioka; Takao Tsuzuki; Satoru Yagi; Jun Kato; Masayuki Uemura; Nobuya Ohara; Tadashi Yoshino; Atsushi Imagawa; Shigeatsu Fujiki; Rie Takata; Kazuhide Yamamoto

BACKGROUND Although endoscopic submucosal dissection (ESD) is expected to reduce the local recurrence of gastric cancers, we still experience cases of recurrence after an ESD. OBJECTIVE To characterize clinical and pathologic features of cases with local recurrence of early gastric cancer after an ESD. DESIGN A prospective cohort study. SETTING AND PATIENTS A total of 306 patients with gastric cancers removed by ESD at Okayama University Hospital and Tsuyama Central Hospital between March 2001 and December 2005 were enrolled. INTERVENTION ESD. MAIN OUTCOME MEASUREMENT Local recurrence. RESULTS The incidence of a complete en bloc resection was 80.4% when pathologically evaluated. Within a median follow-up period of 26 months (12-64 months), a local recurrence was found in 7 cases, all of which had been declared incomplete resections. One patient underwent a second ESD, and the remaining 6 underwent a surgical resection. All removed lesions were mucosal cancers. No lymph-node metastases were found in patients with a surgical resection. There was a significant correlation between the incidence of an incomplete resection and that of a local recurrence (P < .0001). Among the clinical characteristics, tumor size (>30 mm vs <20 mm; odds ratio [OR] 16 mm [95% CI, 2.0-130 mm]) and tumor location (upper vs middle or lower; OR 7.6 [95% CI, 1.3-45]) were identified as factors that were significantly associated with the incidence of a local recurrence. LIMITATION Short follow-up duration. CONCLUSIONS The incidence of a local recurrence was strongly associated with that of an incomplete resection. The frequency of a local recurrence also showed significant correlations with the tumor size and location within the stomach.


The American Journal of Gastroenterology | 2009

Narrow-Band Imaging Provides Reliable Screening for Esophageal Malignancy in Patients With Head and Neck Cancers

Ryuta Takenaka; Yoshiro Kawahara; Hiroyuki Okada; Keisuke Hori; Masafumi Inoue; Seiji Kawano; Daisuke Tanioka; Takao Tsuzuki; Masayuki Uemura; Nobuya Ohara; Susumu Tominaga; Tomoo Onoda; Kazuhide Yamamoto

OBJECTIVES:The narrow-band imaging (NBI) system is a novel technology that enhances the visualization of microvasculature and mucosal patterns. The aim of this study was to assess the reliability of the NBI system for esophageal cancer screening in patients with head and neck cancers.METHODS:A total of 142 patients with head and neck squamous cell carcinoma (SCC) were examined by NBI endoscopy, followed by Lugol chromoendoscopy between April 2006 and June 2008 at the Okayama University Hospital, Okayama, Japan. Detection of SCC and high-grade intraepithelial neoplasia (HGIN) was conducted.RESULTS:The median age of the patients was 64 years (range: 29–86 years), and approximately three-fourths of all the patients were male. In total, 21 superficial lesions in 16 patients were detected by NBI endoscopy. Of these, 4 lesions were diagnosed histologically as SCC and 11 lesions as HGIN. An additional 22 Lugol-voiding lesions ≥5 mm were detected in 19 patients by Lugol chromoendoscopy. Although 1 of these lesions was diagnosed as HGIN, 21 lesions were diagnosed as low-grade intraepithelial neoplasia or lesions without atypical findings. The sensitivity of NBI endoscopy for detecting esophageal SCC and HGIN was 90.9% (95% confidence interval (CI), 58.7–99.8), specificity was 95.4% (95% CI, 90.3–98.3), and accuracy was 95.1% (95% CI, 90.1–98.0).CONCLUSIONS:NBI seems to be useful and reliable for screening for esophageal SCC in patients with head and neck cancers.


Digestive Endoscopy | 2009

Novel chromoendoscopic method using an acetic acid-indigocarmine mixture for diagnostic accuracy in delineating the margin of early gastric cancers

Yoshiro Kawahara; Ryuta Takenaka; Hiroyuki Okada; Seiji Kawano; Masafumi Inoue; Takao Tsuzuki; Daisuke Tanioka; Keisuke Hori; Kazuhide Yamamoto

Background and Aim:  Recent endoscopic imaging techniques for recognition of unclear lesions in the stomach (e.g. narrow band imaging, magnifying endoscopy) require special equipment and therefore are not commonly used. The aim of the present study was to estimate the accuracy of a new chromoendoscopic method using an acetic acid–indigo carmine mixture (AIM) in diagnosing early gastric cancers (EGC).


Gastrointestinal Endoscopy | 2008

Endoscopic submucosal dissection for cancers of the remnant stomach after distal gastrectomy

Ryuta Takenaka; Yoshiro Kawahara; Hiroyuki Okada; Takao Tsuzuki; Satoru Yagi; Jun Kato; Nobuya Ohara; Tadashi Yoshino; Atsushi Imagawa; Shigeatsu Fujiki; Rie Takata; Masahiro Nakagawa; Motowo Mizuno; Tomoki Inaba; Tatsuya Toyokawa; Kohsaku Sakaguchi

BACKGROUND Endoscopic submucosal dissection (ESD) of early gastric cancer is less invasive than surgical resection, and if technically feasible, it may result in less long-term morbidity than does incisional surgery. However, ESD is technically difficult in patients who have had a previous distal gastrectomy. OBJECTIVE Our purpose was to retrospectively assess the results of ESD of early gastric cancer in the remnant stomach. DESIGN Case series. SETTING AND PATIENTS A total of 31 lesions in 30 patients with early remnant gastric cancer were treated with ESD at Okayama University Hospital, Tsuyama Central Hospital, Hiroshima City Hospital, Kagawa Prefectural Central Hospital, and Mitoyo General Hospital from March 2001 to January 2007. INTERVENTION ESD. MAIN OUTCOME MEASUREMENTS En bloc resection rate, complete resection rate, operation time, and complications. RESULTS En bloc resection and complete resection were achieved in 30 (97%) and in 23 (74%) lesions, respectively. The median operation time required for ESD in the remnant stomach was 113 minutes (range 45-450 minutes). Perforation occurred in 4 (13%). The incidence of delayed bleeding requiring blood transfusion was 0%. LIMITATION Short duration of follow-up. CONCLUSIONS ESD is feasible in the remnant stomach but has a relatively high complication rate and should only be performed by experienced endoscopists.


Digestion | 2011

Proton pump inhibitor dose-related healing rate of artificial ulcers after endoscopic submucosal dissection: A prospective randomized controlled trial

Seiji Kawano; Hiroyuki Okada; Yoshiro Kawahara; Keisuke Hori; Daisuke Tanioka; Takao Tsuzuki; Masafumi Inoue; Satoru Yagi; Ryuta Takenaka; Kazuhide Yamamoto

Background/Aims: Two studies have reported on the superiority of a proton pump inhibitor (PPI) compared with a histamine-2-receptor antagonist for the treatment of artificial ulcers after endoscopic submucosal dissection (ESD), but the optimal dose of PPI remains to be defined. The aim of this study was to evaluate the possibility of reducing the dose of PPI. The authors thus compared 30 mg (standard-dose) and 15 mg (half-dose) lansoprazole in terms of ulcer healing, prevention of bleeding and quality of life. Methods: 91 patients with gastric mucosal neoplasm were enrolled. All patients who underwent ESD were administered lansoprazole 30 mg daily during the first week, after which they were randomly assigned to either the standard-dose or half-dose group. Results: One patient in each group developed hematemesis. The stage of ulcers, ulcer reduction ratios and scores on the Gastrointestinal Symptom Rating Scale did not differ at 28 and 56 days. The costs of PPI for the half-dose group and standard-dose group were 7,326.5 and 11,698.4 JPY, respectively, i.e. a difference of 471.9 JPY. Conclusions: A reduced dose of PPI after 1 week of ESD was equivalent in treatment performance to the standard dose and cheaper.


Endoscopy | 2013

Endoscopic submucosal dissection of esophageal cancer using the Mucosectom2 device: a feasibility study

Yoshiro Kawahara; Keisuke Hori; Ryuta Takenaka; Junichiro Nasu; Seiji Kawano; Masahide Kita; Takao Tsuzuki; Minoru Matsubara; Sayo Kobayashi; Hiroyuki Okada; Kazuhide Yamamoto

BACKGROUND AND STUDY AIMS Endoscopic submucosal dissection (ESD) is being increasingly used for superficial esophageal cancers. However, esophageal ESD is technically difficult, time consuming, and less safe compared with endoscopic mucosal resection (EMR). To perform ESD safely and more efficiently, various types of knives have been developed. This study compared the efficacy of our newly developed device, Mucosectom2, with that of conventional devices for esophageal ESD. PATIENTS AND METHODS Between May 2007 and February 2011, ESD was performed for 172 esophageal lesions. Of these, 120 lesions were treated by conventional devices only, whereas 52 lesions were treated by conventional devices and the Mucosectom2. Procedure time, en bloc and R0 resection rates, and adverse events were retrospectively compared between the conventional and Mucosectom2 groups. RESULTS The median procedure time was 48.0 minutes in the conventional group and 21.5 minutes in the Mucosectom2 group; the procedure time was significantly shorter in the Mucosectom2 group than in the conventional group (P < 0.0001). The en bloc and R0 resection rates were lower in the conventional group than those in the Mucosectom2 group, although these differences were not significant. The rate of exposure of the muscle layer in the Mucosectom2 group was significantly lower than in the conventional group (P = 0.04). The rates of perforation and postoperative bleeding were not significantly different between the two groups. CONCLUSIONS This feasibility study suggests that, compared with conventional ESD devices, the Mucosectom2 may decrease the time required for esophageal ESD. Although our groups appeared comparable, they were studied at different times. Endoscopic expertise and endoscope quality may have differed during these periods, thereby affecting the results of our study. A prospective trial is therefore required to confirm our results.


Internal Medicine | 2015

Intramucosal gastric mixed adenoneuroendocrine carcinoma completely resected with endoscopic submucosal dissection

Yasushi Yamasaki; Junichiro Nasu; Kou Miura; Yoshiyasu Kono; Hiromitsu Kanzaki; Keisuke Hori; Takehiro Tanaka; Masahide Kita; Takao Tsuzuki; Minoru Matsubara; Seiji Kawano; Yoshiro Kawahara; Masahiro Tabata; Hiroyuki Okada; Kazuhide Yamamoto

Composite tumors in the stomach composed of adenocarcinoma and neuroendocrine carcinoma are rare. We herein report a case of intramucosal gastric mixed adenoneuroendocrine carcinoma (MANEC) that was treated with endoscopic submucosal dissection (ESD). A 77-year-old man who had previously received ESD for early gastric adenocarcinoma underwent esophagogastroduodenoscopy for screening, which showed a depressed lesion on the lesser curvature of the antrum. The tumor was removed en bloc via ESD and pathologically diagnosed as MANEC. The tumor was located within the mucosal layer, and no lymphovascular invasion was evident. Seven months after the ESD procedure, the patient is currently feeling well without recurrence or metastasis.


World Journal of Gastroenterology | 2011

Proton pump inhibitor step-down therapy for GERD: A multi-center study in Japan

Takao Tsuzuki; Hiroyuki Okada; Yoshiro Kawahara; Ryuta Takenaka; Junichiro Nasu; Hidehiko Ishioka; Akiko Fujiwara; Fumiya Yoshinaga; Kazuhide Yamamoto

AIM To investigate the predictors of success in step-down of proton pump inhibitor and to assess the quality of life (QOL). METHODS Patients who had heartburn twice a week or more were treated with 20 mg omeprazole (OPZ) once daily for 8 wk as an initial therapy (study 1). Patients whose heartburn decreased to once a week or less at the end of the initial therapy were enrolled in study 2 and treated with 10 mg OPZ as maintenance therapy for an additional 6 mo (study 2). QOL was investigated using the gastrointestinal symptom rating scale (GSRS) before initial therapy, after both 4 and 8 wk of initial therapy, and at 1, 2, 3, and 6 mo after starting maintenance therapy. RESULTS In study 1, 108 patients were analyzed. Their characteristics were as follows; median age: 63 (range: 20-88) years, sex: 46 women and 62 men. The success rate of the initial therapy was 76%. In the patients with successful initial therapy, abdominal pain, indigestion and reflux GSRS scores were improved. In study 2, 83 patients were analyzed. Seventy of 83 patients completed the study 2 protocol. In the per-protocol analysis, 80% of 70 patients were successful for step-down. On multivariate analysis of baseline demographic data and clinical information, no previous treatment for gastroesophageal reflux disease (GERD) [odds ratio (OR) 0.255, 95% CI: 0.06-0.98] and a lower indigestion score in GSRS at the beginning of step-down therapy (OR 0.214, 95% CI: 0.06-0.73) were found to be the predictors of successful step-down therapy. The improved GSRS scores by initial therapy were maintained through the step-down therapy. CONCLUSION OPZ was effective for most GERD patients. However, those who have had previous treatment for GERD and experience dyspepsia before step-down require particular monitoring for relapse.


Gut and Liver | 2016

Does Helicobacter pylori Exacerbate Gastric Mucosal Injury in Users of Nonsteroidal Anti-Inflammatory Drugs? A Multicenter, Retrospective, Case-Control Study

Yoshiyasu Kono; Hiroyuki Okada; Ryuta Takenaka; Ko Miura; Hiromitsu Kanzaki; Keisuke Hori; Masahide Kita; Takao Tsuzuki; Seiji Kawano; Yoshiro Kawahara; Kazuhide Yamamoto

Background/Aims The interaction between nonsteroidal anti-inflammatory drugs (NSAIDs) and Helicobacter pylori remains controversial. We retrospectively investigated whether H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users. Methods From January 2010 to December 2013, a total of 245 long-term NSAID (including low-dose aspirin) users who had undergone an esophagogastroduodenoscopy and had been evaluated for H. pylori infection were enrolled at Okayama University Hospital and Tsuyama Chuo Hospital. The degree of gastric mucosal injury was assessed according to the modified Lanza score (MLS). Severe gastric mucosal injury was defined as an MLS ≥4. Univariate and multivariate logistic regression analyses were performed. Results In the univariate analysis, age ≥75 years (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.3 to 4.2), H. pylori-positivity (OR, 2.0; 95% CI, 1.2 to 3.5), and the concomitant use of proton pump inhibitors (PPIs) (OR, 0.48; 95% CI, 0.26 to 0.86) were significantly associated with severe gastric mucosal injury. The multivariate analysis was adjusted by age and sex and demonstrated that H. pylori-positivity (OR, 1.8; 95% CI, 1.0 to 3.3) and the concomitant use of PPIs (OR, 0.53; 95% CI, 0.28 to 0.99) significantly contributed to severe gastric mucosal injury. Conclusions H. pylori infection exacerbates severe gastric mucosal injury among chronic NSAID users.


Digestion | 2006

Reversal of Protein-Losing Enteropathy with Heparin Therapy in an Adult Patient with Congenital Heart Disease

Takao Tsuzuki; Hiroyuki Okada; Ryuta Takenaka; Yoshiro Kawahara; Jun Kato; Hiroaki Okazaki; Hirofumi Kawamoto; Yasushi Shiratori

tion, is a serious problem because PLE reportedly occurs in up to 13.4% of patients, within 10 years of receiving a Fontan operation [2] . Surgical and medical treatments have been reported to be effective in only 60% of PLE cases, and the total morDear Sir, Protein-losing enteropathy (PLE) is defined as the excessive loss of plasma proteins through the intestine [1] . PLE can result from a number of diseases, including congenital heart malformations. PLE after heart surgery, especially a Fontan operaPublished online: March 6, 2007

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