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Dive into the research topics where Tomohiro Tsuchida is active.

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Featured researches published by Tomohiro Tsuchida.


Endoscopy | 2012

Long-term outcomes of endoscopic submucosal dissection for undifferentiated-type early gastric cancer.

Kazuhisa Okada; Junko Fujisaki; T. Yoshida; Hirotaka Ishikawa; Takanori Suganuma; Akiyoshi Kasuga; Masami Omae; Manabu Kubota; Akiyoshi Ishiyama; Toshiaki Hirasawa; Akiko Chino; Masahiko Inamori; Yorimasa Yamamoto; Noriko Yamamoto; Tomohiro Tsuchida; Y. Tamegai; Atsushi Nakajima; Etuo Hoshino; Masahiro Igarashi

BACKGROUND AND STUDY AIM Endoscopic submucosal dissection (ESD) of undifferentiated-type early gastric cancer (UD-EGC) is technically feasible; however, the long-term clinical outcomes of the procedure have not yet been fully investigated. The aim of our study was to elucidate long-term outcomes of ESD for UD-EGC. PATIENTS AND METHODS Between September 2003 and October 2009, a total of 153 patients were diagnosed endoscopically as having UD-EGC fulfilling the expanded criteria for ESD. After informed consent was obtained, 101 patients were selected to undergo ESD and 52 to undergo surgical operation. We assessed the clinical outcomes of ESD in 101 consecutive patients with 103 UD-EGC lesions who were undergoing ESD for the first time. The overall mortality and disease-free survival rates after ESD were evaluated as the long-term outcomes. RESULTS The rates of en bloc and curative resection were 99.0% (102/103) and 82.5% (85/103), respectively. We encountered one patient with nodal metastasis detected by computed tomography before diagnostic ESD, although curative resection of the primary lesion was achieved based on routine histological examination. Among the 78 patients without a past history of malignancy within the previous 5 years in whom curative resection of the primary lesion was achieved, no cases of local recurrence or distant metastasis were observed during follow-up; however, 1 synchronous and 2 metachronous lesions were detected in 2 patients (2.6%) after primary ESD. Thus, estimated over a median follow-up period of 40.0 months (range 19-92 months) and 36.0 months (range 9-92 months), the 3-and 5-year overall mortality rates were 1.9% and 3.9%, respectively, and the 3-and 5-year overall disease-free survival rates were both 96.7%. CONCLUSIONS Although our single-center retrospective study may be considered to be only preliminary, our data indicate that ESD for UD-EGC may yield good long-term outcomes.


Digestive Endoscopy | 2010

THERAPEUTIC OUTCOMES OF ENDOSCOPIC SUBMUCOSAL DISSECTION OF UNDIFFERENTIATED-TYPE INTRAMUCOSAL GASTRIC CANCER WITHOUT ULCERATION AND PREOPERATIVELY DIAGNOSED AS 20 MILLIMETRES OR LESS IN DIAMETER

Yorimasa Yamamoto; Junko Fujisaki; Toshiaki Hirasawa; Akiyoshi Ishiyama; Kazuhito Yoshimoto; Nobue Ueki; Akiko Chino; Tomohiro Tsuchida; Etsuo Hoshino; Naoki Hiki; Tetsu Fukunaga; Takeshi Sano; Toshiharu Yamaguchi; Hiroshi Takahashi; Satoshi Miyata; Noriko Yamamoto; Yo Kato; Masahiro Igarashi

Aim:  The aim of the present study was to examine therapeutic outcomes of endoscopic submucosal dissection (ESD) of undifferentiated‐type intramucosal gastric cancer and the problems of diagnosis.


The American Journal of Gastroenterology | 2011

Sporadic nonampullary duodenal adenoma in the natural history of duodenal cancer: a study of follow-up surveillance.

Kazuhisa Okada; Junko Fujisaki; Akiyoshi Kasuga; Masami Omae; Manabu Kubota; Toshiaki Hirasawa; Akiyoshi Ishiyama; Masahiko Inamori; Akiko Chino; Yorimasa Yamamoto; Tomohiro Tsuchida; Atsushi Nakajima; Etsuo Hoshino; Masahiro Igarashi

OBJECTIVES:Although sporadic nonampullary duodenal adenoma (SNDA) is regarded as a precancerous lesion, its natural course is uncertain. The aim of this study was to evaluate the risk of development of adenocarcinoma in SNDA lesions initially diagnosed as showing low-grade dysplasia (LGD; category 3) or high-grade dysplasia (HGD; category 4.1).METHODS:We analyzed 68 SNDAs, diagnosed based on initial and subsequent biopsies, in 66 consecutive patients. Of these, 46 (43 LGD lesions, 3 HGD lesions) were followed up for ≥6 months without treatment (mean 27.7±16.9 months; range 6–72 months), including 8 lesions that were eventually resected during follow-up. Sixteen lesions (eight LGD lesions, eight HGD lesions) were resected immediately, either endoscopically or surgically, and six lesions were excluded because of a short follow-up (<6 months). The histopathological diagnoses and macroscopic changes were evaluated.RESULTS:Among the 43 LGD lesions followed up for ≥6 months, 34 (79.1%) showed no histopathological changes during follow-up, whereas the remaining 9 (20.9%) showed progression to HGD, including 2 (4.7%) that progressed eventually to noninvasive carcinoma (category 4.2). Macroscopically, 76.7% (33 of 43) of the LGD lesions showed no notable changes in size, 16.3% (7 of 43) became undetectable, 4.7% (2 of 43) reduced in size, and 2.3% (1 of 43) became larger in size. In contrast, all the three HGD lesions that were followed up for ≥6 months remained unchanged histologically, based on biopsy, and showed no notable macroscopic changes, although one of these HGD lesions resected endoscopically revealed evidence of noninvasive carcinoma. Although we diagnosed all lesions as HGD from biopsy samples, a high percentage of cancers (54.5%, 6 of 11) were diagnosed from resected specimens. A multivariate analysis identified HGD diagnosed at first biopsy and a lesion diameter of ≥20 mm as being significantly predictive of progression to adenocarcinoma.CONCLUSIONS:LGD lesions show a low risk of progression to adenocarcinoma, but some risk of progression to HGD, which warrants careful follow-up biopsy. However, HGD lesions and large SNDAs ≥20 mm in diameter show a high risk of progression to adenocarcinoma. Therefore, they should be treated immediately.


Journal of Gastroenterology and Hepatology | 2011

Diagnosis of undifferentiated type early gastric cancers by magnification endoscopy with narrow-band imaging.

Kazuhisa Okada; Junko Fujisaki; Akiyoshi Kasuga; Masami Omae; Toshiaki Hirasawa; Akiyoshi Ishiyama; Masahiko Inamori; Akiko Chino; Yorimasa Yamamoto; Tomohiro Tsuchida; Atsushi Nakajima; Etsuo Hoshino; Masahiro Igarashi

Background and Aims:  The diagnostic use of magnification endoscopy with narrow‐band imaging (ME‐NBI) to assess histopathologically undifferentiated‐type early gastric cancers (UD‐type EGCs) is not well elucidated. The purpose of this study was to examine the comparative relationship between ME‐NBI images and histopathological findings in UD‐type EGCs.


Endoscopy | 2012

Endoscopic mucosal resection and endoscopic submucosal dissection for en bloc resection of superficial pharyngeal carcinomas

Kazuhisa Okada; Tomohiro Tsuchida; Akiyoshi Ishiyama; T. Taniguchi; S. Suzuki; Yusuke Horiuchi; Y. Matsuo; Natsuko Yoshizawa; Takanori Suganuma; Masami Omae; Manabu Kubota; Toshiaki Hirasawa; Yorimasa Yamamoto; Masahiko Inamori; Noriko Yamamoto; Atsushi Nakajima; Junko Fujisaki; Etuo Hoshino; K. Kawabata; Masahiro Igarashi

BACKGROUND AND STUDY AIM Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are being used increasingly to treat superficial oropharyngeal and hypopharyngeal carcinomas. The aim of this study was to clarify whether ESD provided better results than EMR for en bloc and complete resection of superficial pharyngeal carcinomas. PATIENTS AND METHODS A total of 76 superficial pharyngeal carcinomas in 59 consecutively treated patients were included. Patients underwent either conventional EMR (using a transparent cap or strip biopsy) (n = 45 lesions) or ESD (n = 31 lesions) between October 2006 and January 2011. The rates of en bloc resection, complete resection (defined as en bloc resection with tumor-free margins), major complications, and local recurrence were evaluated retrospectively as the therapeutic outcomes. RESULTS ESD yielded significantly higher rates of both en bloc and complete resection compared with EMR (en bloc 77.4 % [24/31] vs. 37.8 % [17/45], P = 0.0002; complete 54.8 % [17/31] vs. 28.9 % [13/45], P = 0.0379). ESD was more frequently complicated by severe laryngeal edema (4/21 [19.0 %] vs. 1/31 [3.2 %], P = 0.1446) and was also more time-consuming (124.9 ± 65.1 minutes vs. 57.2 ± 69.6 minutes; P = 0.0014). Local recurrence was observed more often after EMR than after ESD (3/45 [6.7 %] vs. 0/31 [0 %]), although this difference did not reach statistical significance (P = 0.2658). CONCLUSIONS ESD appears to be a superior method of endoscopic resection of superficial pharyngeal carcinomas for achieving both en bloc and complete resection, although these benefits were also associated with a higher incidence of complications and a significantly longer procedure time. Large prospective studies are needed to compare ESD with conventional EMR for superficial pharyngeal carcinomas.


Digestive Endoscopy | 2009

COMPARISON OF THE DIAGNOSTIC UTILITY OF THE ULTRATHIN ENDOSCOPE AND THE CONVENTIONAL ENDOSCOPE IN EARLY GASTRIC CANCER SCREENING

Yuko Hayashi; Yorimasa Yamamoto; Takanori Suganuma; Kazuhisa Okada; Masami Nego; Shinichi Imada; Mizuka Imai; Kazuhito Yoshimoto; Nobue Ueki; Toshiaki Hirasawa; Naoyuki Uragami; Tomohiro Tsuchida; Junko Fujisaki; Etsuo Hoshino; Hiroshi Takahashi; Masahiro Igarashi

Currently, transnasal esophagogastroduodenoscopy using an ultrathin endoscope is being widely carried out as a screening test for early gastric cancer. We compared the diagnostic utility of ultrathin esophagogastroduodenoscopy with that of conventional esophagogastroduodenoscopy in detecting 42 lesions of early gastric cancer that had a diameter of ≤20 mm. Only 27 lesions (64%) could be accurately diagnosed using ultrathin esophagogastroduodenoscopy. In nine lesions (22%), we failed to discern whether they were malignant. Six lesions (14%) could not even be detected. We found that the diagnostic utility of ultrathin esophagogastroduodenoscopy was inadequate, especially in the case of lesions that were located in the upper third region of the stomach and variegated lesions. In conclusion, the diagnostic utility of ultrathin esophagogastroduodenoscopy might be lower than that of conventional esophagogastroduodenoscopy in terms of screening for early gastric cancer. The disadvantages of ultrathin esophagogastroduodenoscopy should be taken carefully into consideration while examining lesions.


Digestive Endoscopy | 2012

Clinical characterization of gastric lesions initially diagnosed as low-grade adenomas on forceps biopsy.

Akiyoshi Kasuga; Yorimasa Yamamoto; Junko Fujisaki; Kazuhisa Okada; Masami Omae; Akiyoshi Ishiyama; Toshiaki Hirasawa; Akiko Chino; Tomohiro Tsuchida; Masahiro Igarashi; Etsuo Hoshino; Noriko Yamamoto; Minoru Kawaguchi; Rikiya Fujita

Aim:  The aim of this study was to elucidate characteristics of gastric lesions that are initially diagnosed as low‐grade adenomas and to establish appropriate treatment.


Surgery Today | 2009

Twenty-two metachronous multiple signet-ring cell carcinomas treated with repeated gastrectomies and repeated endoscopic mucosal resections: Report of a case

Masanori Tokunaga; Shigekazu Ohyama; Kensuke Kuraoka; Naoki Hiki; Tetsu Fukunaga; Tomohiro Tsuchida; Junko Fujisaki; Noriko Yamamoto; Toshiharu Yamaguchi

A 45-year-old Japanese woman underwent an endoscopic mucosal resection (EMR) for early gastric cancer at the Cancer Institute Hospital in July 1996. The patient then underwent a distal gastrectomy in 2002 because of a new early gastric cancer and repeated EMR for a total of six early gastric cancers in 2007. Finally, a total gastrectomy was performed in February 2008. The pathological examination of the resected specimen indicated 14 synchronous multiple early gastric cancers. Although the incidence of multiple gastric cancers has been reported to range from 5% to 15%, there is usually only a double or triple lesion. Moreover, multiple gastric cancer is typically observed in male elderly patients as differentiated adenocarcinomas. The present case was a young female patient and all of the lesions were intramucosal signet-ring cell adenocarcinomas. The carcinogenetic mechanism in this case may therefore be different from that in typical multiple gastric cancers. A thorough preoperative examination and regular postoperative follow-up are therefore essential for detecting multiple gastric cancers in their early stages.


Digestive Endoscopy | 2017

Effect of direct oral anticoagulants on the risk of delayed bleeding after gastric endoscopic submucosal dissection

Toshiyuki Yoshio; Hideomi Tomida; Ryuichiro Iwasaki; Yusuke Horiuchi; Masami Omae; Akiyoshi Ishiyama; Toshiaki Hirasawa; Yorimasa Yamamoto; Tomohiro Tsuchida; Junko Fujisaki; Takuya Yamada; Eiji Mita; Tomoyuki Ninomiya; Kojiro Michitaka; Masahiro Igarashi

Anticoagulants are used to prevent thromboembolic events. Direct oral anticoagulants (DOAC) are our new choice; however, their effect on bleeding risk for endoscopic treatment has not been reported. We aimed to assess the clinical effect of DOAC compared to warfarin for gastric endoscopic submucosal dissection (ESD).


Endoscopy International Open | 2016

Correlation of the location of superficial Barrett’s esophageal adenocarcinoma (s-BEA) with the direction of gastroesophageal reflux

Masami Omae; Junko Fujisaki; Tomoki Shimizu; Yusuke Horiuchi; Akiyoshi Ishiyama; Toshiyuki Yoshio; Toshiaki Hirasawa; Yorimasa Yamamoto; Tomohiro Tsuchida; Masahiro Igarashi; Yasuyuki Seto

Background: Superficial Barrett’s esophageal adenocarcinoma (s-BEA) in Barrett’s esophagus frequently occurs in the right wall of the esophagus. Our aim was to examine the correlation between the location of s-BEA and the direction of acid and non-acid reflux in patients with Barrett’s esophagus. Patients and methods: We performed 24-h pH monitoring in 33 s-BEA patients using a pH catheter with eight sensors. One sensor was located at the 6 o’clock position in the lower esophagus and sensors 1 – 8 were arranged counterclockwise at the same level. The catheter was positioned at the same level as the s-BEA. We measured the maximal total duration of acid (MTD-A) and non-acid (MTD-NA) reflux. When the direction of MTD-A and MTD-NA coincided with the location of the s-BEA, the case was defined as coincidental and we calculated the rate of coincidence, and the probability of the rate of coincidence was estimated with 95 % confidence intervals (95 %CI). Results: Among the 33 cases of s-BEA examined, the rate of coincidence of both MTD-A and MTD-NA was 24/33 (72.7 %) (95 %CI 0.54 – 0.87). The rate of coincidence of either MTD-A or MTD-NA was 30/33 (90.9 %) (95 %CI 0.76 – 0.98). Conclusions: Our study revealed that the location of s-BEA mostly corresponds to the direction of MTD-A or MTD-NA. Accurate observation of the distribution of acid or non-acid reflux by pH monitoring would aid early detection of s-BEA by endoscopy.

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Junko Fujisaki

Japanese Foundation for Cancer Research

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Akiyoshi Ishiyama

Japanese Foundation for Cancer Research

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Toshiaki Hirasawa

Japanese Foundation for Cancer Research

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Yorimasa Yamamoto

Japanese Foundation for Cancer Research

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Masahiro Igarashi

Japanese Foundation for Cancer Research

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Masami Omae

Japanese Foundation for Cancer Research

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Noriko Yamamoto

Japanese Foundation for Cancer Research

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