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Featured researches published by Hisatomo Ikehara.


Gastrointestinal Endoscopy | 2010

A prospective, multicenter study of 1111 colorectal endoscopic submucosal dissections (with video)

Yutaka Saito; Toshio Uraoka; Yuichiro Yamaguchi; Kinichi Hotta; Naoto Sakamoto; Hiroaki Ikematsu; Masakatsu Fukuzawa; Nozomu Kobayashi; Junichirou Nasu; Tomoki Michida; Shigeaki Yoshida; Hisatomo Ikehara; Yosuke Otake; Takeshi Nakajima; Takahisa Matsuda; Daizo Saito

BACKGROUND Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment for early gastric cancer, although it is not widely used in the colorectum because of technical difficulty. OBJECTIVE To examine the current status of colorectal ESDs at specialized endoscopic treatment centers. DESIGN AND SETTING Multicenter cohort study using a prospectively completed database at 10 specialized institutions. PATIENTS AND INTERVENTIONS From June 1998 to February 2008, 1111 colorectal tumors in 1090 patients were treated by ESD. MAIN OUTCOME MEASUREMENTS Tumor size, macroscopic type, histology, procedure time, en bloc and curative resection rates and complications. RESULTS Included in the 1111 tumors were 356 tubular adenomas, 519 intramucosal cancers, 112 superficial submucosal (SM) cancers, 101 SM deep cancers, 18 carcinoid tumors, 1 mucosa-associated lymphoid tissue lymphoma, and 4 serrated lesions. Macroscopic types included 956 laterally spreading tumors, 30 depressed, 62 protruded, 44 recurrent, and 19 SM tumors. The en bloc and curative resection rates were 88% and 89%, respectively. The mean procedure time ± standard deviation was 116 ± 88 minutes with a mean tumor size of 35 ± 18 mm. Perforations occurred in 54 cases (4.9%) with 4 cases of delayed perforation (0.4%) and 17 cases of postoperative bleeding (1.5%). Two immediate perforations with ineffective endoscopic clipping and 3 delayed perforations required emergency surgery. Tumor size of 50 mm or larger was an independent risk factor for complications, whereas a large number of ESDs performed at an institution decreased the risk of complications. LIMITATIONS No long-term outcome data. CONCLUSIONS ESD performed by experienced endoscopists is an effective alternative treatment to surgery, providing high en bloc and curative resection rates for large superficial colorectal tumors.


Gut | 2006

Endoscopic indications for endoscopic mucosal resection of laterally spreading tumours in the colorectum

Toshio Uraoka; Yutaka Saito; Takahisa Matsuda; Hisatomo Ikehara; Takuji Gotoda; Daizo Saito; Takahiro Fujii

Background: Laterally spreading tumours (LSTs) in the colorectum are usually removed by endoscopic mucosal resection (EMR) even when large in size. LSTs with deeper submucosal (sm) invasion, however, should not be treated by EMR because of the higher risk of lymph node metastasis. Aims: To determine which endoscopic criteria, including high magnification pit pattern analysis, are associated with sm invasion in LSTs and clarify indications for EMR. Methods: Eight endoscopic criteria from 511 colorectal LSTs (granular type (LST-G type); non-granular type (LST-NG type)) were evaluated retrospectively for association with sm invasion, and compared with histopathological findings. Results: LST-NG type had a significantly higher frequency of sm invasion than LST-G type (14% v 7%; p<0.01). Presence of a large nodule in LST-G type was associated with higher sm invasion while pit pattern (invasive pattern), sclerous wall change, and larger tumour size were significantly associated with higher sm invasion in LST-NG type. In 19 LST-G type with sm invasion, sm penetration determined histopathologically occurred under the largest nodules (84%; 16/19) and depressed areas (16%; 3/19). Deepest sm penetration in 32 LST-NG type was either under depressed areas (72%; 23/32) or lymph follicular or multifocal sm invasion (28%; 1/32 and 8/32, respectively). Conclusions: When considering the most suitable therapeutic strategy for LST-G type, we recommend endoscopic piecemeal resection with the area including the large nodule resected first. In contrast, LST-NG type should be removed en bloc because of the higher potential for malignancy and greater difficulty in diagnosing sm depth and extent of invasion compared with LST-G type.


The American Journal of Gastroenterology | 2008

Efficacy of the Invasive/Non-invasive Pattern by Magnifying Chromoendoscopy to Estimate the Depth of Invasion of Early Colorectal Neoplasms

Takahisa Matsuda; Takahiro Fujii; Yutaka Saito; Takeshi Nakajima; Toshio Uraoka; Nozomu Kobayashi; Hisatomo Ikehara; Hiroaki Ikematsu; Kuang-I Fu; Fabian Emura; Akiko Ono; Yasushi Sano; Tadakazu Shimoda; Takahiro Fujimori

OBJECTIVE: During colonoscopy, estimation of the depth of invasion in early colorectal lesions is crucial for an adequate therapeutic management and for such task, magnifying chromoendoscopy (MCE) has been proposed as the best in vivo method. However, validation in large-scale studies is lacking. The aim of this prospective study was to clarify the effectiveness of MCE in the diagnosis of the depth of invasion of early colorectal neoplasms in a large series.METHODS: A total of 4,215 neoplastic lesions were evaluated using MCE from October 1998 to September 2005 at the National Cancer Center Hospital, Tokyo, Japan. Lesions were prospectively classified according to the clinical classification of the pit pattern: invasive pattern or non-invasive pattern. All lesions were histopathologically evaluated.RESULTS: There were 3,371 adenomas, 612 intramucosal cancers (m-ca), 232 submucosal cancers (sm-ca): 52 sm superficial (sm1) and 180 sm deep cancers (sm 2–3). Among lesions diagnosed as invasive pattern, 154 out of 178 (86.5%) were sm2–3, while among lesions diagnosed as non-invasive pattern, 4,011 out of 4,037 (99.4%) were adenomas, m-ca, or sm1. Sensitivity, specificity and diagnostic accuracy of the invasive pattern to differentiate m-ca or sm1 (<1000 μm) from sm2–3 (≥1000 μm) were 85.6%, 99.4%, and 98.8%, respectively.CONCLUSION: The determination of invasive or non-invasive pattern by MCE is a highly effective in vivo method to predict the depth of invasion of colorectal neoplasms.


Gastric Cancer | 2008

Usefulness of a novel electrosurgical knife, the insulation-tipped diathermic knife-2, for endoscopic submucosal dissection of early gastric cancer

Hiroyuki Ono; Noriaki Hasuike; Tetsuya Inui; Kohei Takizawa; Hisatomo Ikehara; Yuichiro Yamaguchi; Yosuke Otake; Hiroyuki Matsubayashi

BackgroundAlthough endoscopic submucosal dissection (ESD) of early gastric cancer using an insulation-tipped diathermic (IT) knife enables the removal of large and ulcerative lesions en bloc, expert endoscopic skill is required. We developed an improved IT knife (IT-2) and compared its efficacy and safety with that of the original IT knife (IT-OM).MethodsWe performed ESD of 602 gastric cancers. Of these, 314 previously untreated single lesions of initial onset were analyzed. Operating time, rate of en-bloc resection, and incidence of complications were compared in the IT-2 group (161 patients) and IT-OM group (153 patients). Lesions were further analyzed as to whether they met the Japanese Gastric Cancer Association indications for ESD or extended indications.ResultsMean resection time was significantly shorter in the IT-2 than in the IT-OM group (48 vs 63 min). There were fewer surgeries lasting longer than 2 h in the IT-2 group than in the IT-OM group (3% vs 12%). En-bloc and margin-free resection rates in the IT-OM and IT-2 groups were 95% and 99%, respectively. Perforations occurred in 3.9% of patients in the IT-OM group and in 5% of patients in the IT-2 group (difference not significant [NS]). The incidence of postoperative hemorrhage was 7.8% in the IT-OM group and 8.7% in the IT-2 group (NS). In both groups, complications were treated endoscopically, and emergency surgery was unnecessary.ConclusionResectability and complication rates were similar in the two groups. However, operating time was shorter with IT-2, irrespective of the indications for the performance of ESD. This study suggests benefits of the IT-2 over the IT-OM.


The American Journal of Gastroenterology | 2008

Does autofluorescence imaging videoendoscopy system improve the colonoscopic polyp detection rate?--a pilot study.

Takahisa Matsuda; Yutaka Saito; Kuang-I Fu; Toshio Uraoka; Nozomu Kobayashi; Takeshi Nakajima; Hisatomo Ikehara; Yumi Mashimo; Tadakazu Shimoda; Yoshitaka Murakami; Adolfo Parra-Blanco; Takahiro Fujimori; Daizo Saito

OBJECTIVES: Colonoscopy is considered the gold standard for the detection of colorectal polyps; however, polyps can be missed with conventional white light (WL) colonoscopy. The aim of this pilot study was to evaluate whether a newly developed autofluorescence imaging (AFI) system can detect more colorectal polyps than WL.METHODS: A modified back-to-back colonoscopy using AFI and WL was conducted for 167 patients in the right-sided colon including cecum, ascending and transverse colon by a single experienced colonoscopist. The patient was randomized to undergo the first colonoscopy with either AFI or WL (group A: AFI-WL, group B: WL-AFI). The time needed for both insertion and examination for withdrawal and all lesions detected in the right-sided colon were recorded.RESULTS: Eighty-three patients were randomized to group A and 84 to group B. The total number of polyps detected by AFI and WL colonoscopy was 100 and 73, respectively. The miss rate for all polyps with AFI (30%) was significantly less than that with WL (49%) (P= 0.01).CONCLUSIONS: AFI detects more polyps in the right-sided colon compared to WL colonoscopy.


Journal of Gastroenterology and Hepatology | 2008

Detectability of colorectal neoplastic lesions using a narrow-band imaging system : A pilot study

Toshio Uraoka; Yutaka Saito; Takahisa Matsuda; Yasushi Sano; Hisatomo Ikehara; Yumi Mashimo; Tsuyoshi Kikuchi; Daizo Saito; Hiroshi Saito

Background and Aim:  Flat and depressed colorectal neoplastic lesions can be difficult to identify using conventional colonoscopy techniques. Narrow‐band imaging (NBI) provides unique views especially of mucosal vascular network and helps in visualization of neoplasia by improving contrast. The aim of this study was to assess the feasibility of using NBI for colorectal neoplasia screening.


British Journal of Surgery | 2007

Gastric perforation during endoscopic resection for gastric carcinoma and the risk of peritoneal dissemination

Hisatomo Ikehara; Takuji Gotoda; Hiroyuki Ono; Ichiro Oda; Daizo Saito

The potential risk of peritoneal seeding following perforation caused by endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) is unknown.


Journal of Gastroenterology and Hepatology | 2010

Diagnosis of depth of invasion for early colorectal cancer using magnifying colonoscopy.

Hisatomo Ikehara; Yutaka Saito; Takahisa Matsuda; Toshio Uraoka; Yoshitaka Murakami

Background and Aims:  Early colorectal cancer (CRC) with submucosal deep (s.m.‐d.) invasion should not be treated with endoscopic mucosal resection due to the higher incidence of lymph‐node metastasis. It is, therefore, clinically important to accurately diagnose s.m.‐d. lesions before treatment.


Pancreas | 2011

Risk factors of familial pancreatic cancer in Japan: Current smoking and recent onset of diabetes

Hiroyuki Matsubayashi; Atsuyuki Maeda; Hideyuki Kanemoto; Katsuhiko Uesaka; Kentaro Yamazaki; Shuichi Hironaka; Yuji Miyagi; Hisatomo Ikehara; Hiroyuki Ono; Alison P. Klein; Michael Goggins

Objectives: In western countries, 7% to 10% of patients with pancreatic cancer (PC) have a familial predisposition to their disease. The aim of this study was to determine the familial susceptibility to PC in Japan. Methods: Five hundred seventy-seven patients with PC and 577 age- and gender-matched controls were analyzed for cancer history in their first-degree relative(s) (FDRs) and demographic factors. Results: The patients with PC were more likely to have an FDR with PC (6.9%) than the controls (2.9%; odds ratio [OR], 2.5; P = 0.02). Three patients (0.5%), but none of the controls, had a family history of PC in multiple FDRs. Smoking, especially current smoking (OR, 1.5; P = 0.005), and diabetes mellitus (OR: 1.7, P = 0.001) were also associated with PC. The odds increased up to 10-fold if the patients were positive for these 3 factors. The patients with familial PC were more likely to be current smokers (40%) and to have diabetes mellitus (32.5%) than the sporadic cases (30.1% and 20.1%; OR, 1.6 and 1.9). Conclusions: A family history of PC is a risk of PC in Japan (6.9%) as is a personal history of diabetes and smoking. It is prudent to inform the kindred of patients with familiar PC of the risk of smoking and to follow carefully if they develop diabetes.Abbreviations: PC - pancreatic cancer, FDR - first-degree relative, OR - odds ratio, FPC - familial pancreatic cancer, DM - diabetes mellitus, SIR - standardized incidence rate, IPMN - intraductal papillary mucinous neoplasm, MDCT - multidetector computed tomography, US - ultrasound, NFPTR - National Familial Pancreas Tumor Registry


Hpb | 2009

Risk of pancreatitis after endoscopic retrograde cholangiopancreatography and endoscopic biliary drainage

Hiroyuki Matsubayashi; Akira Fukutomi; Hideyuki Kanemoto; Atsuyuki Maeda; Kazuya Matsunaga; Katsuhiko Uesaka; Yosuke Otake; Noriaki Hasuike; Yuichiro Yamaguchi; Hisatomo Ikehara; Kohei Takizawa; Kentaroh Yamazaki; Hiroyuki Ono

BACKGROUND Pancreatitis is the most common and serious complication to occur after endoscopic retrograde cholangiopancreatography (ERCP). It is often associated with additional diagnostic modalities and/or treatment of obstructive jaundice. The aim of this study was to determine the risk of post-ERCP pancreatitis associated with pancreaticobiliary examination and endoscopic biliary drainage (EBD). METHODS A total of 740 consecutive ERCP procedures performed in 477 patients were analysed for the occurrence of pancreatitis. These included 470 EBD procedures and 167 procedures to further evaluate the pancreaticobiliary tract using brush cytology and/or biopsy, intraductal ultrasound and/or peroral cholangioscopy or peroral pancreatoscopy. The occurrence of post-ERCP pancreatitis was analysed retrospectively. RESULTS The overall incidence of post-ERCP pancreatitis was 3.9% (29 of 740 procedures). The risk factors for post-ERCP pancreatitis were: being female (6.5%; odds ratio [OR] 2.5, P= 0.02); first EBD procedure without endoscopic sphincterotomy (ES) (6.9%; OR 3.0, P= 0.003), and performing additional diagnostic procedures on the pancreatobiliary duct (9.6%; OR 4.6, P < 0.0001). Pancreatitis after subsequent draining procedures was rare (0.4%; OR for first-time drainage 16.6, P= 0.0003). Furthermore, pancreatitis was not recognized in 59 patients who underwent ES. Seven patients with post-EBD pancreatitis were treated with additional ES. CONCLUSIONS Invasive diagnostic examinations of the pancreaticobiliary duct and first-time perampullary biliary drainage without ES were high-risk factors for post-ERCP pancreatitis. Endoscopic sphincterotomy may be of use to prevent post-EBD pancreatitis.

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Hiroto Miwa

Hyogo College of Medicine

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Jiro Watari

Hyogo College of Medicine

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Tadayuki Oshima

Hyogo College of Medicine

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Hirokazu Fukui

Hyogo College of Medicine

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Takahisa Matsuda

Shiga University of Medical Science

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