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Dive into the research topics where Hayato Yamauchi is active.

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Featured researches published by Hayato Yamauchi.


Surgery Today | 2007

Laparoscopic Appendectomy for Appendiceal Endometriosis Presenting as Acute Appendicitis: Report of a Case

Akihito Idetsu; Hitoshi Ojima; Kana Saito; Hayato Yamauchi; Ei Yamaki; Yasuo Hosouchi; Yasuji Nishida; Hiroyuki Kuwano

Endometriosis is a relatively common disorder in women of reproductive age; however, appendiceal endometriosis is rare. Thus, a definitive diagnosis is likely to be established only by histology of the appendix. We report a case of endometriosis of the appendix in a 42-year-old woman who presented with symptoms of acute appendicitis. We treated the patient by performing laparoscopic appendectomy, which resulted in a good outcome.


Case Reports in Gastroenterology | 2012

Ectopic Sebaceous Glands in the Esophagus: Endoscopic Findings over Three Years

Minoru Fukuchi; Ritsuko Tsukagoshi; Shinji Sakurai; Shinsuke Kiriyama; Katsuhiko Horiuchi; Kazuhisa Yuasa; Masaki Suzuki; Hayato Yamauchi; Yuichi Tabe; Takaharu Fukasawa; Hiroshi Naitoh; Hiroyuki Kuwano

Sebaceous glands in the esophagus are rare and are of particular interest because of their as yet unknown origin. We report a case with ectopic sebaceous glands diagnosed by esophageal endoscopy and biopsy, with follow-up endoscopic examinations for 3 years. Few cases with follow-up endoscopic findings have been reported. In our case, there were no significant overall changes during 3 years of follow-up, but the lesions fluctuated over time. While taking the endoscopic findings of the present or past cases into account, we discuss the possible pathogenic mechanisms of this condition.


International Surgery | 2014

A Case of Very Well-Differentiated Adenocarcinoma With Carcinoid Tumor in the Ascending Colon

Hayato Yamauchi; Shinji Sakurai; Ritsuko Tsukagoshi; Masaki Suzuki; Yuichi Tabe; Takaharu Fukasawa; Shinsuke Kiriyama; Minoru Fukuchi; Hiroshi Naitoh; Hiroyuki Kuwano

Malignant tumors with mixed glandular and neuroendocrine characteristics with at least 30% of each component are classified as mixed adenoneuroendocrine carcinoma (MANEC) by the World Health Organization 2010 classification. We report here a case of very well-differentiated adenocarcinoma accompanied by carcinoid tumor, categorized as MANEC. A 41-year-old Japanese man was clinically diagnosed with ascending colon cancer and underwent right hemicolectomy. Using an immunohistologic technique, the pathologic diagnosis was very well-differentiated adenocarcinoma accompanied by carcinoid tumor and marked eosinophil infiltration, which was categorized as MANEC. By immunohistochemical analysis, tumor cells of the carcinoid component exhibited very low proliferation activity. Our case was thought to be MANEC without high malignant potential. MANEC as per the World Health Organization 2010 classification seems to include tumors with diverse grades of malignancy, and it might need to have subclassifications according to the malignancy potential of the tumor cells.


International Surgery | 2015

A case of mixed adenoneuroendocrine carcinoma of the stomach with focal intestinal metaplasia and hypergastrinemia.

Hayato Yamauchi; Shinji Sakurai; Nobuhiro Nakazawa; Tomonori Yoshida; Yuichi Tabe; Kana Saitoh; Takaharu Fukasawa; Shinsuke Kiriyama; Hiroshi Naitoh; Hiroyuki Kuwano

Among neuroendocrine neoplasms, mixed exocrine and endocrine characteristics with at least 30% of each component are classified into mixed adenoneuroendocrine carcinoma (MANEC), according to the 2010 World Health Organization classification. We experienced a rare case of MANEC of the stomach with focal intestinal metaplasia and hypergastrinemia. A 76-year-old Japanese male was diagnosed as having gastric adenocarcinoma and underwent total gastrectomy. The pathologic diagnosis was MANEC of the stomach accompanied by unusual mucosal atrophy without Helicobacter pylori infection, the characteristics of which were different from both type A and type B atrophic gastritis. The patient has a history of long-term use of a proton pump inhibitor. Additional serum chemistry examination using preoperatively obtained plasma from the patient revealed hypergastrinemia. The mechanism of gastric MANEC carcinogenesis is still unclear, but that might be correlated with unusual intestinal metaplasia and hypergastrinemia in this case.


International Surgery | 2014

Recurrent, Spontaneous Esophageal Ruptures Associated With Antiphospholipid Antibody Syndrome: Report of a Case

Hiroshi Naitoh; Minoru Fukuchi; Shinsuke Kiriyama; Takaharu Fukasawa; Yuichi Tabe; Hayato Yamauchi; Tomonori Yoshida; Kana Saito; Kei Hagiwara; Hiroyuki Kuwano

A 52-year-old man was admitted to our hospital with a spontaneous esophageal rupture (Boerhaave syndrome) and was successfully treated. Eight years after the first incident, he was readmitted with a recurrent rupture. Recurrence of Boerhaave syndrome is extremely rare, with only 7 cases reported in the English literature. During treatment, the patient was also diagnosed with antiphospholipid syndrome (APS). Although APS is known to cause a variety of symptoms due to vascular thrombosis, recurrence of Boerhaave syndrome, coincident with APS, has never been reported. The pathogenesis of Boerhaave syndrome has not been clearly determined. This report serves to increase awareness of the risk of APS, which results in an increased risk of spontaneous rupture of the esophagus.


Hepato-gastroenterology | 2012

Extranodal metastasis predicts poor survival in advanced colorectal cancer.

Tsutsumi S; Watanabe R; Yuichi Tabe; Takaaki Fujii; Hiroki Morita; Kigure W; Toshihide Kato; Hayato Yamauchi; Sakai M; Takayuki Asao; Hiroyuki Kuwano

BACKGROUND/AIMS The prognostic significance of extranodal metastasis (ENM) in colorectal cancer (CRC) is disregarded by the TNM classification system. The influence of ENM on survival among locally advanced CRC patients was examined. METHODOLOGY We reviewed retrospectively the clinical course of 263 patients who underwent surgical resection of locally advanced CRC at our Department between 2005 and 2009. We analyzed the prognostic factors with special reference to the clinicopathological factors of primary tumors. RESULTS Thirty-eight cases of ENM were detected among patients with CRC. Compared with ENM negative cancers, ENM-positive cancers were associated with poorer tumor differentiation grade (p=0.026) and higher prevalence of TNM-stage (p<0.0001), T-status (p=0.024), N-status (p<0.0001) and postoperative recurrence (p<0.0001). In univariate analysis, TNM-stage (p<0.0035), T-status (p=0.002), N-status (p<0.0024) and positive ENM (p<0.0001) were significant predictors of poor survival. Multivariate analyses showed a positive ENM to be a highly significant independent predictor of mortality (HR=1.98, 95% CI=1.23- 3.23, p=0.0053). Survival analyses using Kaplan-Meier curves demonstrated that patients with ENM-positive cancers had significantly poorer survival than patients with ENM-negative cancers. Patients with ENM-negative cancers did not show significantly different survival from patients with node-negative cancers (p=0.272, data not shown). CONCLUSIONS ENM appears to be a strong independent negative prognostic factor of poor survival in locally advanced CRC.


Hepato-gastroenterology | 2012

The efficacy of fondaparinux for the prophylaxis of venous thromboembolism after resection for colorectal cancer.

Tsutsumi S; Reina Yajima; Yuichi Tabe; Takaaki T; Fujii F; Hiroki Morita; Kigure W; Toshihide Kato; Hayato Yamauchi; Toshinaga Suto; Takayuki Asao; Hiroyuki Kuwano

BACKGROUND/AIMS The advantages of combined pharmacological and physical methods for venous thromboembolism (VTE) prophylaxis after colorectal surgery have not been clearly determined. The aim of this study is to compare the efficacy and safety of fondaparinux combined with intermittent pneumatic compression (IPC) with IPC alone for VTE prophylaxis after resection for colorectal cancer. METHODOLOGY Between June 2008 and March 2010, 137 consecutive patients with colorectal cancer (CRC) who underwent colorectal resection in our surgical unit were enrolled in the study. Patients were divided into 2 groups. The IPC group was treated with IPC alone as controls. The fondaparinux group was treated with IPC and received subcutaneous injections of fondaparinux once daily. The aim of this study was to compare the efficacy and safety of fondaparinux combined with IPC with IPC alone for VTE prophylaxis. RESULTS The demographic variables and risk factors, operating time, blood loss and length of the postoperative hospital stay were similar in the two groups. No clinically evident VTE, critical bleeding, and postoperative death occurred during the study period. No adverse reactions due to fondaparinux were observed. CONCLUSIONS In patients undergoing resection of colorectal cancer, receiving fondaparinux and IPC thromboprophylaxis was highly effective, well tolerated and safe. The use of combined modalities for VTE prophylaxis is justified in patients at high risk of VTE.


International Surgery | 2011

The progression potential of peritoneal dissemination nodules from gastrointestinal tumors.

Hayato Yamauchi; Toshinaga Suto; Kigure W; Hiroki Morita; Toshihide Kato; Reina Yajima; Takaaki Fujii; Satoru Yamaguchi; Soichi Tsutsumi; Takayuki Asao; Hiroyuki Kuwano

It is necessary to examine the characteristics of the dissemination nodules to establish a therapeutic strategy for peritoneal dissemination from digestive malignancy. Ki-67 expression as a proliferation marker in peritoneal dissemination nodules was investigated. The subjects were 15 patients with gastrointestinal cancers who underwent resection of the primary tumor and disseminated nodules. The expression of Ki-67 in both primary tumor and peritoneal dissemination nodule from each patient was evaluated by immunohistochemistry. Ki-67 labeling index in the original tumor was higher than that in the disseminated nodule in 13 of 15 patients (P < 0.0001). The mean value of Ki-67 labeling index was 42.2% in the 15 original tumors and 18.7% in the 15 disseminated nodules. Proliferative activity in the disseminated nodules was lower than that in the primary tumors. Further examination about characteristics of cancer dissemination is needed to treat patients with peritoneal metastasis.


Hepato-gastroenterology | 2011

Scheduled prospective tri-weekly modified FOLFOX6 maintenance chemotherapy in the treatment of metastatic colorectal cancer.

Tsutsumi S; Watanabe R; Yuichi Tabe; Takaaki Fujii; Hiroki Morita; Kigure W; Toshihide Kato; Hayato Yamauchi; Takayuki Asao; Hiroyuki Kuwano

BACKGROUND/AIMS Oxaliplatin, which is effective for colorectal cancer (CRC) in combination with 5-fluorouracil (5-FU) and leucovorin (LV), is widely used for metastatic CRC. With the increasing use of oxaliplatin, however, serious adverse events have been experienced, including hematologic and neurologic toxicities. The aim of this study was to evaluate whether tri-weekly modified FOLFOX6 (mFOLFOX6) maintenance chemotherapy is associated with a low incidence of severe hematologic and neurologic toxicities in the treatment of patients with metastatic CRC. METHODOLOGY We developed a new treatment regimen with mFOLFOX6 biweekly for 8-10 consecutive cycles (induction phase) followed by a 3-week rest period, after which treatment was resumed with cycles of tri-weekly mFOLFOX6 at standard doses (maintenance phase). Validity and complications were investigated retrospectively. RESULTS Twenty-nine patients were enrolled in this study. The median progression-free survival (PFS) and overall survival (OS) times were 9.4 months and 23 months, respectively. All patients had peripheral neuropathy during treatment, but grade 3 neurotoxicity was observed in only 2 patients (6.9%). CONCLUSIONS mFOLFOX6 maintenance chemotherapy was associated with a very low incidence of grade 3 hematologic and neurologic toxicities. The toxicities associated with PFS and OS were comparable to those reported in the treatment of patients with metastatic CRC. A tri-weekly mFOLFOX maintenance strategy of alternative treatment with a less-toxic regimen may reduce toxicity and maintain efficacy.


Diagnostic and Therapeutic Endoscopy | 2014

Evaluation of Pharyngeal Function between No Bolus and Bolus Propofol Induced Sedation for Advanced Upper Endoscopy

Shinsuke Kiriyama; Hiroshi Naitoh; Minoru Fukuchi; Takaharu Fukasawa; Kana Saito; Yuichi Tabe; Hayato Yamauchi; Tomonori Yoshida; Hiroyuki Kuwano

This study aimed to assess pharyngeal function between no bolus and bolus propofol induced sedation during gastric endoscopic submucosal dissection. A retrospective study was conducted involving consecutive gastric cancer patients. Patients in the no bolus group received a 3 mg/kg/h maintenance dose of propofol after the initiation of sedation without bolus injection. All patients in the bolus group received the same maintenance dose of propofol with bolus 0.5 mg/kg propofol injection. Pharyngeal functions were evaluated endoscopically for the first 5 min following the initial administration of propofol. Fourteen patients received no bolus propofol induction and 13 received bolus propofol induction. Motionless vocal cords were observed in 2 patients (14%) in the no bolus group and 3 (23%) in the bolus group. Trachea cartilage was not observed in the no bolus group but was apparent in 6 patients (46%) in the bolus group (P < 0.01). Scope stimulated pharyngeal reflex was observed in 11 patients (79%) in the no bolus group and in 3 (23%) in the bolus group (P < 0.01). Propofol induced sedation without bolus administration preserves pharyngeal function and may constitute a safer sedation method than with bolus.

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