Takabayashi, Kaoru



School of Medicine, Center for Diagnostic and Therapeutic Endoscopy (Shinanomachi)


Senior Assistant Professor (Non-tenured)/Assistant Professor (Non-tenured)

Academic Degrees 【 Display / hide

  • 博士, Keio University


Research Areas 【 Display / hide

  • Life Science / Gastroenterology

Research Keywords 【 Display / hide

  • Endoscopy

  • 炎症性腸疾患


Papers 【 Display / hide

  • Novel quantitative assessment indicators for efficiency and precision of endoscopic submucosal dissection in animal training models by analyzing an electrical surgical unit

    Masunaga T., Kato M., Sasaki M., Iwata K., Miyazaki K., Kubosawa Y., Mizutani M., Takatori Y., Matsuura N., Nakayama A., Takabayashi K., Yahagi N.

    Digestive Endoscopy (Digestive Endoscopy)  36 ( 1 ) 19 - 27 2024.01

    ISSN  09155635

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    Objectives: Although endoscopic submucosal dissection (ESD) training is important, quantitative assessments have not been established. This study aimed to explore a novel quantitative assessment system by analyzing an electrical surgical unit (ESU). Methods: This was an ex vivo study. Step one: to identify the novel efficiency indicators, 20 endoscopists performed one ESD each, and we analyzed correlations between their resection speed and electrical status. Step two: to identify the novel precision indicators, three experts and three novices performed one ESD each, and we compared the stability of the electrical status. Step three: three novices in step two performed 19 additional ESDs, and we analyzed the learning curve using novel indicators. Results: Step one: the percentage of total activation time (AT) of ESU in the procedure time (β coefficient, 0.80; P < 0.01) and AT required for submucosal dissection (β coefficient, −0.57; P < 0.01) were significantly correlated with the resection speed. Step two: coefficient of variation of the AT per one pulse (0.16 [range, 0.13–0.17] vs. 0.26 [range, 0.20–0.41], P = 0.049) and coefficient of variation of the peak electric power per pulse during mucosal incision (0.14 [range, 0.080–0.15] vs. 0.25 [range, 0.24–0.28], P = 0.049) were significantly lower in the experts than in the novices. Regarding the learning curve, the percentage of total AT of ESU in the procedure time and AT required for submucosal dissection had a trend of improvement. Conclusion: Novel indicators identified by analyzing ESU enable quantitative assessment for endoscopist's skill.

  • Downregulation of chemokine receptor 9 facilitates CD4<sup>+</sup>CD8αα<sup>+</sup> intraepithelial lymphocyte development

    Ono K., Sujino T., Miyamoto K., Harada Y., Kojo S., Yoshimatsu Y., Tanemoto S., Koda Y., Zheng J., Sayama K., Koide T., Teratani T., Mikami Y., Takabayashi K., Nakamoto N., Hosoe N., London M., Ogata H., Mucida D., Taniuchi I., Kanai T.

    Nature Communications (Nature Communications)  14 ( 1 )  2023.12

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    Intestinal intraepithelial lymphocytes (IELs) reside in the gut epithelial layer, where they help in maintaining intestinal homeostasis. Peripheral CD4+ T cells can develop into CD4+CD8αα+ IELs upon arrival at the gut epithelium via the lamina propria (LP). Although this specific differentiation of T cells is well established, the mechanisms preventing it from occurring in the LP remain unclear. Here, we show that chemokine receptor 9 (CCR9) expression is low in epithelial CD4+CD8αα+ IELs, but CCR9 deficiency results in CD4+CD8αα+ over-differentiation in both the epithelium and the LP. Single-cell RNA sequencing shows an enriched precursor cell cluster for CD4+CD8αα+ IELs in Ccr9 −/− mice. CD4+ T cells isolated from the epithelium of Ccr9 −/− mice also display increased expression of Cbfβ2, and the genomic occupancy modification of Cbfβ2 expression reveals its important function in CD4+CD8αα+ differentiation. These results implicate a link between CCR9 downregulation and Cbfb2 splicing upregulation to enhance CD4+CD8αα+ IEL differentiation.

  • Effectiveness of endoscopic resection for colorectal neoplasms in ulcerative colitis: a multicenter registration study

    Hirai M., Yanai S., Kunisaki R., Nishio M., Watanabe K., Sato T., Ishihara S., Anzai H., Hisabe T., Yasukawa S., Maeda Y., Takishima K., Ohno A., Shiga H., Uraoka T., Itoi Y., Ogata H., Takabayashi K., Yoshida N., Saito Y., Takamaru H., Kawasaki K., Esaki M., Tsuruoka N., Hisamatsu T., Matsumoto T.

    Gastrointestinal Endoscopy (Gastrointestinal Endoscopy)  98 ( 5 ) 806 - 812 2023.11

    ISSN  00165107

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    Background and Aims: Patients with ulcerative colitis (UC) are at risk of developing colorectal cancer. The feasibility of endoscopic resection (ER) for UC-associated neoplasia has been suggested, but its efficacy and safety remain unclear. We aimed to assess the efficacy and safety of ER for colorectal neoplasms in patients with UC. Methods: This was a retrospective, multicenter cohort study of patients with UC who initially underwent ER or surgery for colorectal neoplasms between April 2015 and March 2021. Patients who had prior colorectal neoplastic lesions were excluded. Results: Among 213 men and 123 women analyzed, the mean age at UC onset was 41.6 years, and the mean age at neoplasia diagnosis was 56.1 years for 240 cases of total colitis, 59 cases of left-sided colitis, 31 cases of proctitis, and 6 cases of segmental colitis. EMR was performed for 142 lesions, and endoscopic submucosal dissection (ESD) was performed for 96 lesions. The perforation rate was 2.5% for all 238 lesions removed by ER and 6.3% for the 96 lesions removed by ESD. Among 146 ER lesions followed up with endoscopy, the local recurrence rate was 2.7%. The incidence of metachronous neoplasia after ER was 6.1%. All patients were followed a median of 34.7 months after initial treatment, and 5 died (all surgical cases). Overall survival was significantly higher in the ER group than in the surgery group (P =.0085). Conclusions: ER for colorectal neoplasms in UC may be acceptable in selected cases, although follow-up for metachronous lesions is necessary.

  • Intensive endoscopic resection strategy for multiple duodenal polyposis associated with familial adenomatous polyposis

    Iwata K., Kato M., Sasaki M., Miyazaki K., Kubosawa Y., Masunaga T., Mizutani M., Hayashi Y., Takatori Y., Matsuura N., Nakayama A., Takabayashi K., Kanai T., Yahagi N.

    Journal of Gastroenterology and Hepatology (Australia) (Journal of Gastroenterology and Hepatology (Australia))  38 ( 9 ) 1592 - 1597 2023.09

    ISSN  08159319

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    Background and Aim: Multiple duodenal polyposis associated with familial adenomatous polyposis (FAP) is a high risk of duodenal cancer development. We evaluated the feasibility of intensive endoscopic resection that is a comprehensive treatment strategy combining multiple kinds of endoscopic treatments. Methods: This is a retrospective observational study. From January 2012 to July 2022, a total of 28 consecutive patients in FAP who underwent endoscopic resection for multiple duodenal polyposis more than twice were included. Various endoscopic treatments, such as cold polypectomy (CP), endoscopic mucosal resection (EMR), underwater EMR (UEMR), endoscopic submucosal dissection (ESD), and endoscopic papillectomy (EP), were applied depending on lesions size and location. We evaluated individual information from patients' medical records, including patient characteristics, lesion characteristics, details of endoscopic treatment, pathologic findings, and Spigelman index (SI). We compared the differences in the number of treatments and observation periods with and without SI decrease. Results: A total of 1040 lesions were removed by 138 sessions of endoscopic resections. The median follow-up period was 3.2 years. At the beginning of the endoscopic intervention, median SI was 9 (6–11) and the proportion of Spigelman stage (SS) IV was 61%. Repeated endoscopic treatments finally reduced SI in 26 patients (93%), and the proportion of SS IV significantly decreased to 13% with every endoscopic treatment. The mean SI change was −4.2 points per year (95% confidence interval: −0.6 to −5.9). There were no patients required surgical duodenectomy during the follow-up period. Conclusion: Intensive resection has a potential of downstaging duodenal lesions associated with FAP.

  • Modified double-layered suturing for a mucosal defect after colorectal endoscopic submucosal dissection (Origami method) (with video)

    Masunaga T., Kato M., Sasaki M., Iwata K., Miyazaki K., Kubosawa Y., Mizutani M., Takatori Y., Matsuura N., Nakayama A., Takabayashi K., Yahagi N.

    Gastrointestinal Endoscopy (Gastrointestinal Endoscopy)  97 ( 5 ) 962 - 969 2023.05

    ISSN  00165107

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    Background and Aims: Through-the-scope clips (TTSCs) are among the most common devices used to close colorectal post–endoscopic submucosal dissection (ESD) defects. Although TTSCs are easy to deliver, even to the proximal colon, simple clipping of large defects results in mucosa–mucosa closure, which could be unreliable. We developed a novel endoscopic closure technique using a modified double-layered suturing called the origami method (OGM). This method closes not only the mucosal layer but also the muscle layer with only TTSCs, which can obtain robust closure even for large defects. This study aimed to evaluate the feasibility of this new closure method for colorectal post-ESD defects. Methods: This retrospective observational study was conducted at a tertiary care hospital. We reviewed the cases of the OGM attempted after colorectal ESD at our institute between October 2021 and October 2022 and measured the clinical characteristics and outcomes of enrolled cases. Results: The OGM was attempted in 47 cases after colorectal ESD. Thirty-one cases (66%) were in the proximal colon, 5 (11%) in the distal colon, 6 (13%) in the upper rectum, and 5 (10%) in the lower rectum. The median defect size was 38 mm, with the largest being 85 mm. Complete closure was achieved in 44 cases (94%), including all lower rectum cases. No perforations were caused by clips during closure, and delayed perforation and bleeding were not observed. Conclusions: This new closure method is feasible and recommended. The OGM could achieve reliable closure of large defects in any location, including the proximal colon and thick-walled lower rectum, using only TTSCs.

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Research Projects of Competitive Funds, etc. 【 Display / hide

  • 超拡大内視鏡による潰瘍性大腸炎組織学的粘膜治癒の確立、関連癌診断法の樹立


    MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Early-Career Scientists , Principal investigator


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Memberships in Academic Societies 【 Display / hide

  • 日本内科学会

  • 日本消化器病学会

  • 日本消化器内視鏡学会

  • 日本肝臓学会

  • 日本消化管学会


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