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Dive into the research topics where Akiyoshi Ishiyama is active.

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Featured researches published by Akiyoshi Ishiyama.


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.


Japanese Journal of Clinical Oncology | 2008

Irinotecan plus cisplatin for therapy of small-cell carcinoma of the esophagus: report of 12 cases from single institution experience.

Keisho Chin; Satoshi Baba; Hisashi Hosaka; Akiyoshi Ishiyama; Nobuyuki Mizunuma; Eiji Shinozaki; Mitsukuni Suenaga; Takuyo Kozuka; Yasuyuki Seto; Noriko Yamamoto; Kiyohiko Hatake

BACKGROUND Esophageal small-cell cancer is a rare disease, and standard therapy has not yet been established. METHODS A total of 12 esophageal small-cell carcinoma patients were treated with CPT-11 (70 mg/m(2)) on Days 1 and 15 and CPT-11 plus CDDP (80 mg/m(2)) on Day 1 with each cycle repeated every 4 weeks at our institution. RESULTS A total of 46 chemotherapy courses were given (median, 3.5). There were two complete responses and eight partial responses. The median survival time was 417 (97-1626) days, and three patients were still alive for >40 months. Grade 4 neutropenia was observed in two patients, Grade 4 anemia in one patient, Grade 3-4 diarrhea in three patients and Grade 3-4 hyponatremia in three patients. Other adverse reactions seen were mild with no treatment-related deaths observed. CONCLUSIONS To our knowledge, this is the first report of the series of more than 10 patients with small-cell carcinoma of the esophagus treated with the same chemotherapy regimen. The combination of CPT-11 and CDDP appears to be effective therapy of this disease with acceptable toxicity profile. We believe that this regimen is one of the options to be considered for treatment of esophageal small-cell carcinoma.


Digestive Endoscopy | 2012

CURRENT STATUS OF TRAINING FOR ENDOSCOPIC SUBMUCOSAL DISSECTION FOR GASTRIC EPITHELIAL NEOPLASM AT CANCER INSTITUTE HOSPITAL, JAPANESE FOUNDATION FOR CANCER RESEARCH, A FAMOUS JAPANESE HOSPITAL

Yorimasa Yamamoto; Junko Fujisaki; Akiyoshi Ishiyama; Toshiaki Hirasawa; Masahiro Igarashi

Aim:  Endoscopic submucosal dissection (ESD) is relatively difficult compared with endoscopic mucosal resection (EMR), thus, proper training is essential for the safe performance of the procedure. The aim of this study is to clarify the current status of training for ESD for gastric epithelial neoplasm by following the performance of 13 preceptees.


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 | 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.


Digestive Endoscopy | 2012

Successful en bloc resection of a 5 cm symptomatic sessile gastric lipoma by endoscopic submucosal dissection.

Tomohiko Yoshida; Junko Fujisaki; Takanori Suganuma; Akiyoshi Kasuga; Kazuhisa Okada; Masami Oomae; Toshiaki Hirasawa; Akiyoshi Ishiyama; Akiko Chino; Yorimasa Yamamoto; Tomohiro Tuchida; Etuo Hoshino; Masahiro Igarashi

Gastric lipomas can usually be resected endoscopically or surgically, but there has yet to be an established treatment method. Here we report a case of a 5 cm sessile gastric lipoma that was successfully removed by en bloc resection using endoscopic submucosal dissection (ESD). A 70-year-old woman presented with nausea, obstruction and abdominal pain that were caused by a sessile gastric submucosal tumor that was 5 cm in diameter and occupied the anterior wall of the gastric antrum; the tumor resulted in ball valve syndrome. Endoscopic ultrasound revealed a well-circumscribed, hyperechoic mass that was mainly located in the third layer of the gastric wall without infiltrating the muscularis propria. We diagnosed the submucosal tumor as a clinically suspicious of gastric lipoma.We selected the ESD method as a less-invasive alternative to surgery. The ESD procedure was performed using a needle knife and an IT Knife2 (KD-611L; Olympus, Tokyo, Japan) (Fig. 1). Complete en bloc resection was achieved in 75 min. There were no specific technical difficulties or complications. We withdrew the complete resected specimen orally with a large caliber, soft, oblique cap while sucking by grasping it with the forceps. The size of the tumor was 50 ¥ 38 ¥ 28 mm. The en bloc specimen enabled us to accurately evaluate the histopathological diagnosis, and the tumor was proven to be a lipoma (Fig. 2). The patient’s abdominal symptoms disappeared completely after ESD, and she was discharged on postoperative day 7.To our knowledge, there have been no other reports of sessile gastric lipomas over 5 cm that have been removed by endoscopic en bloc resection. There are only three reported cases of endscopic resection for sessile gastric lipomas greater than 4 cm in diameter. Based on our experience and past reports, ESD is a feasible option for diagnostic treatment with minimal invasiveness for sessile gastric lipomas up to 5 cm in diameter. This method could become the standard treatment.


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).

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Junko Fujisaki

Japanese Foundation for Cancer Research

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Tomohiro Tsuchida

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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