Faculty Profiles - YAMASAKI Yasushi

Papers - YAMASAKI Yasushi

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Acetic Acid-Indigo Carmine Chromocolonoscopy for Proximal Serrated Lesions: A Randomized, Three-Arm Colonoscopy Study. International journal

Hideaki Kinugasa, Sakiko Hiraoka, Sayo Kobayashi, Minoru Matsubara, Teruya Nagahara, Reiji Higashi, Kensuke Takei, Masayasu Ohmori, Takashi Nakamura, Takao Tsuzuki, Shouichi Tanaka, Ryosuke Hirai, Junki Toyosawa, Yuki Aoyama, Yasushi Yamasaki, Toshihiro Inokuchi, Masahiro Takahara, Takehiro Tanaka, Toshiharu Mitsuhashi, Motoyuki Otsuka

The American journal of gastroenterology 2025.3

Language：English Publishing type：Research paper (scientific journal)

OBJECTIVES: Aggressive colorectal cancer (CRC) frequently originates from serrated lesions (SLs), particularly in the proximal colon, which are challenging to detect using standard screening colonoscopy. Although duplicate examinations or chromocolonoscopies are recommended for detecting proximal SLs, evidence from randomized trials is limited. We evaluated the effectiveness of tandem colonoscopy with an acetic acid-indigo carmine mixture (AIM) for detecting SLs in the proximal colon compared to white-light imaging (WLI) and indigo carmine (IC). METHODS: This three-arm, multicenter, randomized controlled trial involving nine institutions enrolled patients undergoing colonoscopy and assigned them randomly to the WLI, IC, or AIM group. The primary outcomes were the SL-detection rate (SDR) of proximal lesions during the second examination (SDR2nd) and SL additional rate (SAR). Secondary outcomes included the detection and additional rates of other polyps, factors contributing to SAR, and complications. RESULTS: Between 2021 and 2024, 1,319 participants with 1,267 polyps were included in the analysis. With AIM, the SDR2nd and SAR were significantly higher compared to WLI or IC (WLI vs. AIM: 2.7% vs. 14.0%, p<.001; IC vs. AIM: 7.9% vs. 14.0%, p=.002, and WLI vs. AIM: 22.4% vs. 69.3%, p<.001; IC vs. AIM: 45.8% vs. 69.3%, p=.001). AIM conferred a higher adenoma-detection rate (ADR)2nd than with WLI (10.5% vs. 24.7%; p<.001) and was an independent factor for SAR (odds ratio [95% confidence interval]: 7.79 [3.76-17.08]). No major adverse events were observed. CONCLUSIONS: AIM significantly improved proximal colon SDRs and outperformed WLI and IC. The relationship between SDR and CRC incidence warrants further investigation.

DOI： 10.14309/ajg.0000000000003411

PubMed

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Changes of leucine-rich alpha 2 glycoprotein could be a marker of changes of endoscopic and histologic activity of ulcerative colitis. International journal

Yuki Aoyama, Sakiko Hiraoka, Eriko Yasutomi, Toshihiro Inokuchi, Takehiro Tanaka, Kensuke Takei, Shoko Igawa, Keiko Takeuchi, Masahiro Takahara, Junki Toyosawa, Yasushi Yamasaki, Hideaki Kinugasa, Jun Kato, Hiroyuki Okada, Motoyuki Otsuka

Scientific reports 15 ( 1 ) 5248 - 5248 2025.2

Language：English Publishing type：Research paper (scientific journal)

Leucine-rich alpha 2 glycoprotein (LRG) is one of the serum biomarkers for disease activity of ulcerative colitis (UC). We focused on the correlation between the changes of LRG and the changes of endoscopic and histologic activity of UC, in comparison to the changes of fecal calprotectin (Fcal), fecal immunochemical test (FIT), and C-reactive protein (CRP). Seventy-nine patients with two or more colonoscopies were enrolled, and 123 paired colonoscopies and 121 paired biopsies were examined. With regard to the change of endoscopic/histologic activity between the preceding and subsequent colonoscopy, there was improvement (n = 29/45), unchanging (n = 63/36), and worsening (n = 31/40). The correlations between the changes of marker levels and endoscopic/histologic activity were Fcal; r = 0.50/0.39 and FIT; r = 0.41/0.40, LRG; r = 0.42/0.40 and CRP; r = 0.22/0.17. Furthermore, when the correlation between the changes of LRG levels and the changes of endoscopic/histological activity was compared with those of other markers, the correlation of LRG tended to be superior to those of CRP (CRP vs. LRG; p = 0.08/0.01). LRG is equivalent to fecal markers and superior to CRP, when inferring changes in disease activity of UC based on changes in its level.

DOI： 10.1038/s41598-025-89615-8

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Short- and longer-term learning effects from virtual scale endoscopy videos: a useful tool for colorectal lesion size estimation (with video). International journal

Ryosuke Hirai, Hideaki Kinugasa, Mikako Ishiguro, Junki Toyosawa, Yuki Aoyama, Shoko Igawa, Yasushi Yamasaki, Toshihiro Inokuchi, Masahiro Takahara, Seiji Kawano, Sakiko Hiraoka, Motoyuki Otsuka

Gastrointestinal endoscopy 2024.10

Language：English Publishing type：Research paper (scientific journal)

BACKGROUND AND AIMS: Accurate assessment of colorectal polyp size is crucial for determining treatment and surveillance policies. However, visual estimation of lesion diameter is often inaccurate, making simple and effective educational tools essential. We aimed to evaluate the learning effects of virtual scale endoscopy (VSE). METHODS: Thirty-three endoscopists first watched pre-learning videos for SET1. They then estimated the diameters of 20 lesions and referred to instructional videos with VSE for self-study. Subsequently, they watched the post-learning videos for SET2 and estimated the lesion diameters. The error between the estimated and correct lesion sizes of both sets was compared. To evaluate longer-term learning effects, participants answered SET3 and SET4, which consisted of the same questions as SET2 and SET1, respectively, 2-3 months later without watching the instructional video for SET2. RESULTS: The error in the participants' estimation of the correct lesion diameter improved from SET1 to SET2 (34.7 mm ± 6.6 vs. 30.7 mm ± 7.7; p = 0.048), with a significant learning effect and error improvement specifically among non-experts (35.2 mm ± 5.3 vs. 30 mm ± 6.8; p = 0.028). In the SET3 and SET4, participants' errors indicated that the learning effect was well maintained (SET2 vs. SET3; 30.7 mm ± 7.7 vs. 28.6 mm ± 7.2; p = 0.1, and SET1 and SET4: 34.7 mm ± 6.6 vs. 31.7 mm ± 7.1; p = 0.025). CONCLUSIONS: VSE videos are a valuable learning tool for estimating lesion diameter, particularly for novice endoscopists, both in the short- and longer-term.

DOI： 10.1016/j.gie.2024.10.038

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増大号炎症性腸疾患2024 主題炎症性腸疾患の内科治療基本治療薬(5-ASA製剤,副腎皮質ステロイド,チオプリン製剤)

平岡佐規子, 石黒美佳子, 豊澤惇希, 青山祐樹, 井川翔子, 竹内桂子, 山崎泰史, 井口俊博, 衣笠秀明, 髙原政宏, 大塚基之, 金谷信彦, 近藤喜太, 田中健大

胃と腸 59 ( 10 ) 1453 - 1461 2024.10

Gastric peroral endoscopic myo-neurotomy as less-invasive bariatric surgery in porcine models: an experimental study

Kenta Hamada, Yasushi Yamasaki, Akinobu Takaki, Takehiro Tanaka, Hiroyuki Okada

iGIE 3 ( 3 ) 358 - 365 2024.9

Publishing type：Research paper (scientific journal)

Background and Aims: Obesity is a global health problem, and less-invasive treatments are warranted. We developed a novel endoscopic intervention named peroral endoscopic myo-neurotomy (POEM-N) that is performed at the greater curvature of the gastric antrum as a bariatric/metabolic procedure and assessed its feasibility using porcine models. Methods: Six live pigs were divided into 3 groups of 2: POEM-N with a high-fat diet (HFD) (POEM-N group); sham procedure with HFD (HF-control group); and sham procedure with normal diet (N-control group). All pigs were fed the diets for 2 weeks, underwent POEM-N or sham procedure, and were observed for 2 weeks after the procedure. The primary outcome was the safety and feasibility of POEM-N. Adverse events and histology of the area after POEM-N were evaluated to assess the procedure's safety and feasibility. Secondary outcomes were changes in body weight and glycolipid levels. Results: There was no severe worsening of vital signs during or after the POEM-N procedure. All pigs were well and food intake was good, with no delayed adverse events. Excessive storage of dietary residue, deformity of the gastric antrum, and fold concentration were observed after POEM-N, as expected. Histologic examination revealed hypertrophic regeneration of Auerbach's plexus, which regulates gastric peristalsis, in both POEM-N pigs. After the procedure, HFD-induced weight gain in the POEM-N pigs slowed, and the increase in serum and liver cholesterol levels was suppressed. Conclusions: We applied POEM-N as a bariatric/metabolic procedure and showed its safety and feasibility using porcine models.

DOI： 10.1016/j.igie.2024.06.002

Scopus

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Adverse events after different endoscopic resection procedures for small and intermediate-sized colorectal polyps. International journal

Junki Toyosawa, Yasushi Yamasaki, Yuki Aoyama, Kensuke Takei, Shoko Igawa, Toshihiro Inokuchi, Hideaki Kinugasa, Masahiro Takahara, Sakiko Hiraoka, Hiroyuki Okada, Motoyuki Otsuka

Digestive diseases (Basel, Switzerland) 2024.8

Language：English Publishing type：Research paper (scientific journal)

BACKGROUND AND STUDY AIMS: Cold snare polypectomy (CSP) and underwater endoscopic mucosal resection (UEMR) have been developed recently, in addition to conventional methods, but adverse events of each method have not been fully clarified. We compared outcomes of each method for the appropriate choice. PATIENTS AND METHODS: Patients who underwent CSP, endoscopic mucosal resection (EMR)/hot snare polypectomy (HSP) or UEMR for small and intermediate-sized colorectal polyps between April 2017 and June 2020 were retrospectively examined. The rate of adverse events and recurrences due to each method were determined as main outcomes. Clinical factors related with adverse events were examined. RESULTS: A total of 1,025 patients with 3,163 polyps underwent polypectomy using any of the methods. CSP, EMR/HSP and UEMR were performed for 704 (22.2%), 2,145 (67.8%) and 314 polyps (9.9%), and median size for each method was 4, 6 and 7 mm, respectively. Delayed bleeding for CSP, EMR/HSP and UEMR was 0%, 0.2% and 0.6% (P = 0.15), and perforation was 0%, 0.1% and 0%, respectively (P = 0.62). Recurrence after CSP, EMR/HSP and UEMR was 0.1%, 0.04% and 1.0%, respectively (P < 0.01). Recurrence for UEMR was significantly higher in the early stage of procedure introduction (P = 0.001). Oral anticoagulants were the risk factor for delayed bleeding (P < 0.01, respectively). CONCLUSIONS: There was no significant difference regarding adverse events among each method for small and intermediate-sized polyps, although recurrence rate after UEMR was higher than other methods.

DOI： 10.1159/000540365

PubMed

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【消化管粘膜下腫瘍のすべて】十二指腸十二指腸粘膜下腫瘍の内視鏡診断

山崎泰史, 岩室雅也, 川野誠司, 田中彰一, 田中健大

消化器内視鏡 36 ( 7 ) 1033 - 1038 2024.7

Language：Japanese Publisher：(株)東京医学社

＜文献概要＞はじめに十二指腸において,粘膜下腫瘍(submucosal tumor:SMT)の形態をとる病変はさまざまであるが,そのほとんどは良性病変である。一方,治療対象となる悪性病変も稀ではあるが存在する。両者の鑑別には,色調や大きさ,表面性状に加えて,病変の硬さ(鉗子による感触で評価するcushion signの有無)が重要である。また,EUSによる病変の主座やエコーレベルの評価も鑑別診断の手助けとなる。

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Other Link： https://search.jamas.or.jp/default/link?pub_year=2024&ichushi_jid=J02312&link_issn=&doc_id=20240724080022&doc_link_id=%2Faq9syokd%2F2024%2F003607%2F019%2F1033-1038%26dl%3D0&url=https%3A%2F%2Fwww.medicalonline.jp%2Fjamas.php%3FGoodsID%3D%2Faq9syokd%2F2024%2F003607%2F019%2F1033-1038%26dl%3D0&type=MedicalOnline&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00004_2.gif

Innovative submucosal injection solution for endoscopic resection with phosphorylated pullulan: a preclinical study. International journal

Takuya Satomi, Yukari Ochi, Takumi Okihara, Hiroki Fujii, Yasuhiro Yoshida, Katsumi Mominoki, Haruko Hirayama, Junki Toyosawa, Yasushi Yamasaki, Seiji Kawano, Yoshiro Kawahara, Hiroyuki Okada, Motoyuki Otsuka, Akihiro Matsukawa

Gastrointestinal endoscopy 99 ( 6 ) 1039 - 1047 2024.6

Language：English Publishing type：Research paper (scientific journal)

BACKGROUND AND AIMS: A submucosal injection solution is used to assist in endoscopic surgery. The high viscosity of current solutions makes them difficult to inject. In the present study, we developed an extremely low-viscosity, easy-to-use submucosal injection solution using phosphorylated pullulan (PPL). METHODS: The PPL solutions were prepared at different concentrations, and their viscosities were measured. The mucosal elevation capacity was evaluated using excised porcine stomachs. Controls included 0.4% sodium hyaluronate (SH), 0.6% sodium alginate (SA), and saline. To evaluate the practicality, the catheter injectability of 0.7% PPL was measured, and EMR and endoscopic submucosal dissection (ESD) were performed using the stomach and colorectum of live pigs. As controls, 0.4% SH and saline were used. RESULTS: The PPL solutions were of extremely low viscosity compared to the solutions of 0.4% SH and 0.6% SA. Nevertheless, the mucosal elevation capacity of PPL solutions for up to 0.7% concentration was similar to that of 0.4% SH, and 0.7% PPL was less resistant to catheter infusion than 0.4% SH and 0.6% SA. In live pig experiments with endoscopic mucosal resection and ESD, snaring after submucosal injection of 0.7% PPL was easier than with 0.4% SH, ESD with 0.7% PPL produced less bubble formation than with 0.4% SH, and the procedure time tended to be shorter with 0.7% PPL than with 0.4% SH because of the shorter injection time. CONCLUSIONS: The PPL solution is an innovative and easy-to-use submucosal injection solution.

DOI： 10.1016/j.gie.2024.01.015

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Association of screening tool scores with overall survival in older patients with unresectable gastrointestinal or biliary pancreatic cancer: A retrospective study. International journal

Shoko Inoo, Yoshiyasu Kono, Hiromitsu Kanzaki, Shigeru Horiguchi, Hironari Kato, Yasushi Yamasaki, Shoichiro Hirata, Sakiko Kuraoka, Katsunori Matsueda, Shotaro Okanoue, Takuya Satomi, Kenta Hamada, Masaya Iwamuro, Seiji Kawano, Yoshiro Kawahara, Hiroyuki Okada, Motoyuki Otsuka

Journal of geriatric oncology 15 ( 4 ) 101714 - 101714 2024.5

UnderwaterとUnder-gelでの大腸腫瘍性病変に対する境界診断能の検討

豊澤惇希, 山崎泰史, 青山祐樹, 井川翔子, 井口俊博, 衣笠秀明, 高原政宏, 平岡佐規子, 大塚基之

Gastroenterological Endoscopy 66 ( Suppl.1 ) 969 - 969 2024.4

神経線維腫症の消化管合併症に関する検討

本田真奈美, 岩室雅也, 山崎泰史, 田中健大, 川野誠司, 平岡佐規子, 河原祥朗, 大塚基之

日本消化器病学会雑誌 121 ( 臨増総会 ) A349 - A349 2024.3

神経線維腫症の消化管合併症に関する検討

本田真奈美, 岩室雅也, 山崎泰史, 田中健大, 川野誠司, 平岡佐規子, 河原祥朗, 大塚基之

日本消化器病学会雑誌 121 ( 臨増総会 ) A349 - A349 2024.3

Utility of Combined Use of Transabdominal Ultrasonography and Fecal Immunochemical Test Examinations in Ulcerative Colitis.

Masahiro Takahara, Sakiko Hiraoka, Masayasu Ohmori, Keiko Takeuchi, Kensuke Takei, Yuki Aoyama, Eriko Yasutomi, Shoko Igawa, Toshihiro Inokuchi, Junki Toyosawa, Yasushi Yamasaki, Hideaki Kinugasa, Keita Harada, Hideki Onishi, Hiroyuki Okada

Acta medica Okayama 78 ( 1 ) 79 - 83 2024.2

Language：English Publishing type：Research paper (scientific journal)

This study examined the utility of the combined use of transabdominal ultrasonography (TUS) and fecal immunochemical testing (FIT) to detect mucosal inflammation, vis-a-vis the Mayo endoscopic subscore (MES), in ulcerative colitis (UC). Sixty-three UC patients who underwent TUS and FIT were retrospectively enrolled. For TUS, the colon was divided into five segments, and the bowel wall thickness was measured and evaluated. The accuracy of FIT (> 100 ng/ml) in detecting mucosal inflammation (MES>0) was 0.93, whereas that of TUS (BWT>2 mm) in each segment was 0.84-0.97. The combined use of TUS and FIT may be helpful in noninvasive treatment strategies.

DOI： 10.18926/AMO/66674

PubMed

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Colorectal Ganglioneuromas Associated with Cowden Syndrome

Toshiki Ozato, Yasushi Yamasaki, Toshihiro Inokuchi, Motoyuki Otsuka

Internal Medicine 2024

大腸神経節細胞腫により診断に至ったCowden症候群の1例

本田真奈美, 山崎泰史, 豊澤惇希, 井口俊博, 衣笠秀明, 高原政宏, 田中健大, 平岡佐規子, 大塚基之

日本消化器病学会中国支部例会・日本消化器内視鏡学会中国支部例会プログラム・抄録集 120回・131回 68 - 68 2023.11

Low Patient Weight and Long Intubation Time Are Key Factors for Pain during Colonoscopy.

Shohei Oka, Keita Harada, Shumpei Yamamoto, Eriko Yasutomi, Shoko Igawa, Masayasu Ohmori, Mami Hirai, Yasushi Yamasaki, Toshihiro Inokuchi, Hideaki Kinugasa, Masahiro Takahara, Sakiko Hiraoka, Hiroyuki Okada

Acta medica Okayama 77 ( 5 ) 471 - 478 2023.10

Language：English Publishing type：Research paper (scientific journal)

Although the clinical usefulness of colonoscopy has been established, the procedure remains painful for many patients. This study was designed to clarify the factors predicting colonoscopy-related pain. We evaluated 283 consecutive patients who completed a first-ever, total colonoscopy without sedatives or analgesics. The severity of pain symptoms was evaluated by a numeric rating scale (NRS) in a questionnaire immediately after the colonoscopy. Patient backgrounds and endoscopic findings were analyzed to evaluate their association with pain. Out of 283 patients, 53 scored their pain 0-1 on the NRS while 48 scored it 6-10. We defined the colonoscopies of the former and latter patients as painless and painful, respectively, and compared the two. Multivariate analyses revealed that low body weight (OR 4.95, 95%CI 1.89-12.99) and longer intubation time (OR 3.63, 95%CI 1.46-9.03) were significant risk factors for painful colonoscopy. To identify factors contributing to the increased intubation time, we divided subjects into short- and long-intubation-time groups based on a median insertion time of 7 min. Older age (OR 2.28, 95%CI 1.31-3.98), previous abdominal surgery (OR 1.93, 95%CI 1.13-3.32) and findings of invasive cancer (OR 10.90, 95%CI 1.34-88.90) were significant factors for longer intubation time.

DOI： 10.18926/AMO/65969

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10mm以上20mm以下の大腸鋸歯状病変(SSL)に対するUnderwater EMR(UEMR)の有効性

大森正泰, 山崎泰史, 豊澤惇希, 山本峻平, 衣笠秀明, 原田馨太, 平岡佐規子, 竹中龍太, 大塚基之

Gastroenterological Endoscopy 65 ( Suppl.2 ) 2000 - 2000 2023.10

Efficacy of endoscopic submucosal resection with a ligation device for small rectal neuroendocrine tumor: study protocol of a multicenter open-label randomized control trial (BANDIT trial)

Kazunori Takada, Kenichiro Imai, Takanori Yamada, Ken Ohata, Takashi Kanesaka, Yasuaki Nagami, Yasushi Yamasaki, Hideki Kobara, Yasuhiro Inokuchi, Akiko Chino, Shinjiro Yamaguchi, Hisatomo Ikehara, Takuji Kawamura, Yohei Yabuuchi, Yasuhiko Mizuguchi, Hiroaki Ikematsu, Chizu Yokoi, Santa Hattori, Kazuya Ohno, Yashiro Yoshizawa, Masakatsu Fukuzawa, Yosuke Tsuji, Jun Konishi, Takeshi Yamamura, Satoshi Osawa, Shiro Oka, Takuto Hikichi, Kazutomo Togashi, Kingo Hirasawa, Toshio Uraoka, Yoji Takeuchi, Hideyuki Chiba, Yoriaki Komeda, Hisashi Doyama, Mari S Oba, Yutaka Saito

2023.9

Publisher：Research Square Platform LLC

Abstract

Background: Endoscopic resection is widely accepted as a local treatment for rectal neuroendocrine tumors sized ≤ 10 mm. However, there is no consensus on the best method for the endoscopic resection of rectal neuroendocrine tumors. As a simplified endoscopic procedure, endoscopic submucosal resection with a ligation device (ESMR-L) indicates a histologically complete resection rate comparable to that of endoscopic submucosal dissection (ESD). We hypothesized that ESMR-L than ESD would be preferred for rectal neuroendocrine tumors. Hence, this trial aimed to verify whether ESMR-L is non-inferior to ESD in terms of histologically complete resection rate.Methods: This is a prospective, open-label, multicenter, non-inferiority, randomized controlled trial of two parallel groups, conducted at the Shizuoka Cancer Center and 31 other institutions in Japan. Patients with a lesion endoscopically diagnosed as a rectal neuroendocrine tumor ≤ 10 mm are eligible for inclusion. A total of 266 patients will be recruited and randomized to undergo either ESD or ESMR-L. The primary endpoint is the rate of en bloc resection with histologically tumor-free margins (R0 resection). Secondary endpoints include en bloc resection rate, procedure time, adverse events, hospitalization days, total devices and agents cost, adverse event rate between groups with and without resection site closure, outcomes between expert and non-expert endoscopists, and factors associated with R0 resection failure. The sample size is determined based on the assumption that the R0 resection rate will be 95.2% in the ESD group and 95.3% in the ESMR-L group, with a non-inferiority margin of 8%. With a one-sided significance level of 0.05 and a power of 80%, 226 participants are required. Assuming a dropout rate of 15%, 266 patients will be included in this study.Discussion: This is the first multicenter randomized controlled trial comparing ESD and ESMR-L for the R0 resection of rectal neuroendocrine tumors ≤ 10 mm. This will provide valuable information for standardizing endoscopic resection methods for rectal neuroendocrine tumors.Trial registration: Japan Registry of Clinical Trials, jRCTs042210124. Registered on Jan 6, 2022.

DOI： 10.21203/rs.3.rs-3337089/v1

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Other Link： https://www.researchsquare.com/article/rs-3337089/v1.html

血流豊富な粘膜下腫瘍の形態を呈した上行結腸血管周囲類上皮細胞腫の1例

青山祐樹, 井口俊博, 平岡佐規子, 豊澤惇希, 竹井健介, 井川翔子, 山崎泰史, 衣笠秀明, 高原政宏, 庄司良平, 近藤喜太, 柳井広之, 大塚基之

日本消化器内視鏡学会中国支部例会 130回 81 - 81 2023.6

【表在性非乳頭部十二指腸上皮性腫瘍(SNADET)の内視鏡診断と治療】治療病変の状況に応じた内視鏡治療戦略とそのすみ分け(3,000例の多施設共同研究から)

加藤元彦, 竹内洋司, 布袋屋修, 小山恒男, 野中哲, 吉水祥一, 角嶋直美, 大圃研, 山本博徳, 原裕子, 土山寿志, 土肥統, 山崎泰史, 上山浩也, 滝本見吾, 蔵原晃一, 田島知明, 阿部展次, 中山敦史, 小田一郎, 矢作直久

消化器内視鏡 35 ( 6 ) 760 - 765 2023.6

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Papers - YAMASAKI Yasushi