 | 山﨑 友裕 （ヤマザキ トモヒロ）
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Last Updated :2024/05/15
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一般的な消化器疾患から胆道・膵疾患の診断治療を行っております。
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- Ken Kamata; Hajime Imai; Hisakazu Matsumoto; Yukitaka Yamashita; Takao Kato; Katsuhisa Nishi; Shunsuke Omoto; Kosuke Minaga; Kentaro Yamao; Tomoko Hyodo; Sung‐Woon Im; Akane Hara; Tomoe Yoshikawa; Rei Ishikawa; Ayana Okamoto; Tomohiro Yamazaki; Atsushi Nakai; Kazuomi Ueshima; Yasutaka Chiba; Mamoru Takenaka; Tomohiro Watanabe; Masayuki Kitano; Masatoshi KudoJGH Open 7 9 659 - 666 2023年09月Abstract Background and Aim A multicenter, open‐label randomized Phase II trial was conducted to determine whether low‐dose gemcitabine plus nab‐paclitaxel (GnP) could improve tolerability and show equivalent efficacy to the standard‐dose GnP for elderly patients with metastatic pancreatic cancer. Methods Consecutive patients aged ≥65 years with metastatic pancreatic cancer who presented at one of four Japanese referral centers between November 2016 and January 2021 were enrolled. The 60 patients were randomly assigned to low‐ or standard‐dose groups with a 1:1 ratio. Patients in the low‐dose GnP group received gemcitabine at a dose of 250 mg/m2 and nab‐paclitaxel at 125 mg/m2. Results Low‐dose GnP significantly decreased the rate of cases requiring dose reduction (16.7% vs 63.3%). The response rate (36.7% vs 33.3%) and progression‐free survival (7.3 vs 8 months) were comparable between the low‐ and standard‐dose groups as determined by independent review. The difference in the median overall survival between the two groups was not significant (7.9 vs 12 months). The proportion of patients with hematologic and non‐hematologic treatment‐related adverse events was comparable between the two groups. Conclusion Low‐dose GnP had an equivalent efficacy to conventional therapy; however, it did not reduce adverse events.
- Ayana Okamoto; Ken Kamata; Takeshi Miyata; Tomoe Yoshikawa; Rei Ishikawa; Tomohiro Yamazaki; Atsushi Nakai; Shunsuke Omoto; Kosuke Minaga; Kentaro Yamao; Mamoru Takenaka; Yasutaka Chiba; Toshiharu Sakurai; Naoshi Nishida; Masayuki Kitano; Masatoshi KudoClinical endoscopy 55 4 558 - 563 2022年07月 [査読有り]
Background/Aims: Bispectral index (BIS) monitors process and display electroencephalographic data and are used to assess the depth of anesthesia. This study retrospectively evaluated the usefulness of BIS monitoring during endoscopic ultrasonography (EUS). Methods: This study included 725 consecutive patients who underwent EUS under sedation with propofol. BIS monitoring was used in 364 patients and was not used in 361. The following parameters were evaluated: (1) median dose of propofol; (2) respiratory and circulatory depression; (3) occurrence of body movements; (4) awakening score >8 at the time; and (5) awakening score 2 hours after leaving the endoscopy room. Results: The BIS group received a significantly lower median dose of propofol than the non-BIS group (159.2 mg vs. 167.5 mg; p=0.015) in all age groups. For patients aged ≥75 years, the reduction in heart rate was significantly lower in the BIS group than in the non-BIS group (1.2% vs. 9.1%; p=0.023). Moreover, the occurrence of body movements was markedly lower in the BIS group than in the non-BIS group (8.5% vs. 39.4%; p<0.001). Conclusions: During EUS examination, BIS monitoring is useful for maintaining a constant depth of anesthesia, especially in patients 75 years of age or older. - Yasuo Otsuka; Ken Kamata; Tomoko Hyodo; Takaaki Chikugo; Akane Hara; Hidekazu Tanaka; Tomoe Yoshikawa; Rei Ishikawa; Ayana Okamoto; Tomohiro Yamazaki; Atsushi Nakai; Shunsuke Omoto; Kosuke Minaga; Kentaro Yamao; Mamoru Takenaka; Yasutaka Chiba; Tomohiro Watanabe; Takuya Nakai; Ippei Matsumoto; Yoshifumi Takeyama; Masatoshi KudoSurgical Endoscopy 36 5 3254 - 3260 2022年05月 [査読有り]
BACKGROUND: The value of contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) for T-staging in patients with extrahepatic bile duct cancer was evaluated. METHODS: This single-center, retrospective study included consecutive patients with extrahepatic bile duct cancer who underwent surgical resection after preoperative EUS, CH-EUS, and contrast-enhanced CT (CE-CT) examinations between June 2014 and August 2017. The capacity of these modalities for T-staging of extrahepatic bile duct cancer was evaluated by assessing invasion beyond the biliary wall into the surrounding tissue, gallbladder, liver, pancreas, duodenum, portal vein system (portal vein and/or superior mesenteric vein), inferior vena cava, and hepatic arteries (proper hepatic artery, right. and/or left. hepatic artery). Blind reading of EUS, CH-EUS, and CE-CT images was performed by two expert reviewers each. RESULTS: 38 patients were eligible for analysis, of which eight had perihilar bile duct cancer and 30 had distal bile duct cancer. Postoperative T-staging was T1 in 6, T2 in 16, and T3 in 16 cases. CH-EUS was superior to CE-CT for diagnosing invasion beyond the biliary wall into surrounding tissue (92.1% vs. 45.9%, P = 0.0002); the ability to detect invasion to other organs did not differ significantly between the two modalities. The accuracy of CH-EUS for T-staging of tumors was better than that of CE-CT (73.7% vs. 39.5%, P = 0.0059). CH-EUS tended to have a better accuracy than EUS for the diagnosis of invasion beyond the biliary wall into the surrounding tissue (92.1% vs. 78.9%, P = 0.074) and T-staging (73.7% vs. 60.5%, P = 0.074). CONCLUSION: CH-EUS is useful for T-staging of extra hepatic bile duct cancer, especially in terms of invasion beyond the biliary wall into the surrounding tissue. - Hidekazu Tanaka; Ken Kamata; Rika Ishihara; Hisashi Handa; Yasuo Otsuka; Akihiro Yoshida; Tomoe Yoshikawa; Rei Ishikawa; Ayana Okamoto; Tomohiro Yamazaki; Atsushi Nakai; Shunsuke Omoto; Kosuke Minaga; Kentaro Yamao; Mamoru Takenaka; Tomohiro Watanabe; Naoshi Nishida; Masatoshi KudoJournal of gastroenterology and hepatology 37 5 841 - 846 2022年05月BACKGROUND AND AIM: Contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) is useful for the diagnosis of lesions inside and outside the digestive tract. This study evaluated the value of artificial intelligence (AI) in the diagnosis of gastric submucosal tumors by CH-EUS. METHODS: This retrospective study included 53 patients with gastrointestinal stromal tumors (GISTs) and leiomyomas, all of whom underwent CH-EUS between June 2015 and February 2020. A novel technology, SiamMask, was used to track and trim the lesions in CH-EUS videos. CH-EUS was evaluated by AI using deep learning involving a residual neural network and leave-one-out cross-validation. The diagnostic accuracy of AI in discriminating between GISTs and leiomyomas was assessed and compared with that of blind reading by two expert endosonographers. RESULTS: Of the 53 patients, 42 had GISTs and 11 had leiomyomas. Mean tumor size was 26.4 mm. The consistency rate of the segment range of the tumor image extracted by SiamMask and marked by the endosonographer was 96% with a Dice coefficient. The sensitivity, specificity, and accuracy of AI in diagnosing GIST were 90.5%, 90.9%, and 90.6%, respectively, whereas those of blind reading were 90.5%, 81.8%, and 88.7%, respectively (P = 0.683). The κ coefficient between the two reviewers was 0.713. CONCLUSIONS: The diagnostic ability of CH-EUS results evaluated by AI to distinguish between GISTs and leiomyomas was comparable with that of blind reading by expert endosonographers.
- Kentaro Yamao; Masakatsu Tsurusaki; Kota Takashima; Hidekazu Tanaka; Akihiro Yoshida; Ayana Okamoto; Tomohiro Yamazaki; Shunsuke Omoto; Ken Kamata; Kosuke Minaga; Mamoru Takenaka; Takaaki Chikugo; Yasutaka Chiba; Tomohiro Watanabe; Masatoshi KudoDiagnostics (Basel, Switzerland) 11 10 2021年10月BACKGROUND: Pancreatic cancer (PC) exhibits extremely rapid growth; however, it remains largely unknown whether the early stages of PC also exhibit rapid growth speed equivalent to advanced PC. This study aimed to investigate the natural history of early PCs through retrospectively assessing pre-diagnostic images. METHODS: We examined the data of nine patients, including three patients with carcinoma in situ (CIS), who had undergone magnetic resonance cholangiopancreatography (MRCP) to detect solitary main pancreatic duct (MPD) stenosis >1 year before definitive PC diagnosis. We retrospectively analyzed the time to diagnosis and first-time tumor detection from the estimated time point of first-time MPD stenosis detection without tumor lesion. RESULTS: The median tumor size at diagnosis and the first-time tumor detection size were 14 and 7.5 mm, respectively. The median time to diagnosis and first-time tumor detection were 26 and 49 months, respectively. CONCLUSIONS: No studies have investigated the PC history, especially that of early PCs, including CIS, based on the initial detection of MPD stenosis using MRCP. Assessment of a small number of patients showed that the time to progression can take several years in the early PC stages. Understanding this natural history is very important in the clinical setting.
- Akihiro Yoshida; Mamoru Takenaka; Kota Takashima; Hidekazu Tanaka; Ayana Okamoto; Tomohiro Yamazaki; Atsushi Nakai; Shunsuke Omoto; Kosuke Minaga; Ken Kamata; Kentaro Yamao; Yoriaki Komeda; Naoshi Nishida; Masatoshi KudoJournal of clinical medicine 10 13 2021年06月 [査読有り]
Unsuccessful stent replacement in transpapillary biliary drainage with plastic stents (PSs) has a significant impact on patient prognosis; thus, a safe and reliable replacement method is required. We aimed to compare the snare-over-the-guidewire (SOG) method, wherein the PS lumen is used as an access route to the biliary tract and the PS is removed with a snare inserted via the inserted guidewire, with the conventional side-of-stent (SOS) method, wherein the biliary approach is performed from the side of the PS. This retrospective single-center study included 244 consecutive patients who underwent biliary PS replacement between January 2018 and July 2020. The procedural success rates were compared between the two methods. A predictive analysis of unsuccessful PS replacement was also performed. The procedural success rate in the SOG group was significantly higher than that in the SOS group (p = 0.026). In the proximal biliary stenosis lesion, the same trend was observed (p = 0.025). Multivariate analysis also showed that the SOS method (p = 0.0038), the presence of proximal biliary stenosis (p < 0.0001), and parapapillary diverticulum (p = 0.0007) were predictors of unsuccessful PS replacement. The SOG method may be useful for biliary PS replacement, especially in cases of proximal hilar bile duct stenosis. - Mamoru Takenaka; Makoto Hosono; Madan M Rehani; Yasutaka Chiba; Rei Ishikawa; Ayana Okamoto; Tomohiro Yamazaki; Atsushi Nakai; Shunsuke Omoto; Kosuke Minaga; Ken Kamata; Kentaro Yamao; Shiro Hayashi; Tsutomu Nishida; Masatoshi KudoDigestive endoscopy : official journal of the Japan Gastroenterological Endoscopy Society 34 3 579 - 586 2021年06月OBJECTIVES: The transpapillary drainage by endoscopic retrograde cholangiopancreatography (ERCP-D) cannot be performed without fluoroscopy, and there are many situations in which fluoroscopy is required even in endoscopic ultrasound-guided drainage (EUS-D). Previous studies have compared the efficacy, but not the radiation exposure of EUS-D and ERCP-D. While radiation exposure in ERCP-D has been previously evaluated, there is a paucity of information regarding radiation doses in EUS-D. This study aimed to assess radiation exposure in EUS-D compared with that in ERCP-D. METHODS: This retrospective single-center cohort study included consecutive patients who underwent EUS-D and ERCP-D between October 2017 and March 2019. The air kerma (AK: mGy), kerma-area product (KAP: Gycm2 ), fluoroscopy time (FT: min), and procedure time (PT: min) were assessed. The invasive probability weighting method was used to qualify the comparisons. RESULTS: We enrolled 372 and 105 patients who underwent ERCP-D and EUS-D, respectively. The mean AK, KAP, and FT in the EUS-D group were higher by 53%, 28%, and 27%, respectively, than those in the ERCP-D group, whereas PT was shorter by approximately 11% (AK; 135.0 vs. 88.4, KAP; 28.1 vs. 21.9, FT; 20.4 vs. 16.0, PT; 38.7 vs. 43.5). The sub-analysis limited to biliary drainage cases showed the same trend (AK; 128.3 vs. 90.9, KAP; 27.0 vs. 22.2, FT; 16.4 vs. 16.1, PT; 32.5 vs. 44.4). CONCLUSIONS: This is the first study to assess radiation exposure in EUS-D compared with that in ERCP-D. Radiation exposure was significantly higher in EUS-D than in ERCP-D, despite the shorter procedure time.
- Tomohiro Yamazaki; Mamoru Takenaka; Shunsuke Omoto; Tomoe Yoshikawa; Rei Ishikawa; Ayana Okamoto; Atsushi Nakai; Kosuke Minaga; Ken Kamata; Kentaro Yamao; Yoriaki Komeda; Tomohiro Watanabe; Naoshi Nishida; Keiko Kamei; Ippei Matsumoto; Yoshifumi Takeyama; Takaaki Chikugo; Yasutaka Chiba; Masatoshi KudoJournal of clinical medicine 10 9 2021年04月This study aimed to investigate whether the incorporation of contrast-enhanced harmonic endoscopic ultrasound (CH-EUS) into the international consensus guidelines (ICG) for the management of intraductal papillary mucinous neoplasm (IPMN) could improve its malignancy diagnostic value. In this single-center retrospective study, 109 patients diagnosed with IPMN who underwent preoperative CH-EUS between March 2010 and December 2018 were enrolled. We analyzed each malignancy diagnostic value (sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV)) by replacing fundamental B-mode EUS with CH-EUS as the recommended test for patients with worrisome features (WF) (the CH-EUS incorporation ICG) and comparing the results to those obtained using the 2017 ICG. The malignancy diagnostic values as per the 2017 ICG were 78.9%, 42.3%, 60.0%, and 64.7% for Se, Sp, PPV, and NPV, respectively. The CH-EUS incorporation ICG plan improved the malignancy diagnostic values (Se 78.9%/Sp, 53.8%/PPV, 65.2%/NPV 70.0%). CH-EUS may be useful in determining the appropriate treatment strategies for IPMN.
- Kosuke Minaga; Mamoru Takenaka; Kentaro Yamao; Ken Kamata; Shunsuke Omoto; Atsushi Nakai; Tomohiro Yamazaki; Ayana Okamoto; Rei Ishikawa; Tomoe Yoshikawa; Yasutaka Chiba; Tomohiro Watanabe; Masatoshi KudoWorld journal of gastroenterology 26 9 947 - 959 2020年03月 [査読有り]
BACKGROUND: Although several techniques for endoscopic ultrasound-guided biliary drainage (EUS-BD) are available at present, an optimal treatment algorithm of EUS-BD has not yet been established. AIM: To evaluate the clinical utility of treatment method conversion during single endoscopic sessions for difficult cases in initially planned EUS-BD. METHODS: This was a single-center retrospective analysis using a prospectively accumulated database. Patients with biliary obstruction undergoing EUS-BD between May 2008 and April 2016 were included. The primary outcome was to evaluate the improvement in EUS-BD success rates by converting the treatment methods during a single endoscopic session. Secondary outcomes were clarification of the factors leading to the conversion from the initial EUS-BD and the assessment of efficacy and safety of the conversion as judged by technical success, clinical success, and adverse events (AEs). RESULTS: A total of 208 patients underwent EUS-BD during the study period. For 18.8% (39/208) of the patients, the treatment methods were converted to another EUS-BD technique from the initial plan. Biliary obstruction was caused by pancreatobiliary malignancies, other malignant lesions, biliary stones, and other benign lesions in 22, 11, 4, and 2 patients, respectively. The reasons for the difficulty with the initial EUS-BD were classified into the following 3 procedures: Target puncture (n = 13), guidewire manipulation (n = 18), and puncture tract dilation (n = 8). Technical success was achieved in 97.4% (38/39) of the cases and clinical success was achieved in 89.5% of patients (34/38). AEs occurred in 10.3% of patients, including bile leakage (n = 2), bleeding (n = 1), and cholecystitis (n = 1). The puncture target and drainage technique were altered in subsequent EUS-BD procedures in 25 and 14 patients, respectively. The final technical success rate with 95%CI for all 208 cases was 97.1% (95%CI: 93.8%-98.9%), while that of the initially planned EUS-BD was 78.8% (95%CI: 72.6%-84.2%). CONCLUSION: Among multi-step procedures in EUS-BD, guidewire manipulation appeared to be the most technically challenging. When initially planned EUS-BD is technically difficult, treatment method conversion in a single endoscopic session may result in successful EUS-BD without leading to severe AEs. - Tanaka H; Kamata K; Takenaka M; Yoshikawa T; Ishikawa R; Okamoto A; Yamazaki T; Nakai A; Omoto S; Minaga K; Yamao K; Sakurai T; Watanabe T; Nishida N; Chiba Y; Kitano M; Kudo MDigestive and liver disease : official journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver 51 8 1130 - 1134 2019年08月 [査読有り]
BACKGROUND AND AIMS: Contrast-enhanced harmonic endoscopic ultrasonography (CH-EUS) is used for the diagnosis of pancreatic cancer (PC). Here, we examined the usefulness of CH-EUS for evaluating therapeutic responses in PC. METHODS: The study included 23 patients with PC who received chemotherapy. Patients underwent contrast-enhanced computed tomography (CE-CT) and CH-EUS before chemotherapy and at the time of evaluation of the therapeutic response. Patients with a ≧50% reduction in serum carbohydrate antigen 19-9 levels after chemotherapy were defined as "super responders". The incidence of an avascular area in the tumor on CH-EUS after chemotherapy was compared between "super responders" and non-super responders. RESULTS: Nine patients were included in the "super responders" group.Tumor reduction rates did not differ significantly between CE-CT and CH-EUS in the "super responders". The appearance of an avascular area was detected in 7 of 9 super responders (77.8%) and in 4 of 14 non-super responders (28.6%), and the difference was significant (P = 0.036). The mean survival time of patients with an avascular area after chemotherapy was longer than that of without an avascular area. CONCLUSIONS: Detection of avascular areas by CH-EUS after chemotherapy may predict long-term survival of patients with PC. - Kentaro Yamao; Mamoru Takenaka; Tomoe Yoshikawa; Rei Ishikawa; Ayana Okamoto; Tomohiro Yamazaki; Atsushi Nakai; Shunsuke Omoto; Ken Kamata; Kosuke Minaga; Satoru Hagiwara; Toshiharu Sakurai; Naoshi Nishida; Yasutaka Chiba; Tomohiro Watanabe; Masatoshi KudoInternal medicine (Tokyo, Japan) 58 14 1993 - 2002 2019年07月 [査読有り]
Objective Although modified FOLFIRINOX (mFOLFIRINOX, mFFX) is widely used for patients with advanced pancreatic ductal adenocarcinoma (PDAC), maintenance of the standard dose intensity is often difficult due to the high incidence of neutropenic events. Pegylated granulocyte colony-stimulating factor (G-CSF) (Peg G) is a long-lasting G-CSF agent that is applicable for prophylaxis against neutropenic complications. The aim of this study was to assess the clinical safety and efficacy of mFFX combined with secondary prophylaxis using Peg G in advanced PDAC patients. Methods Advanced PDAC patients who had received more than two cycles of mFFX were analyzed. The clinical safety and efficacy were compared between patients in the Peg G group and those in the non-Peg G group in a retrospective manner. Results Among 45 patients treated with mFFX, 28 exhibited grade 3-4 neutropenia or febrile neutropenia. Among these 28 patients, 4 who received only 1 or 2 mFFX cycles were excluded from this study. Finally, 11 patients in the Peg G group and 13 in the non-Peg G group were enrolled. The combination therapy with Peg G and mFFX markedly prolonged the progression-free survival compared with the non-Peg G group, and its effects were associated with a reduced incidence of neutropenic events as well as lower rates of dosage reduction, delayed chemotherapy due to neutropenic events and altered blood cell counts after chemotherapy. Conclusion The scheduled administration of secondary prophylactic Peg G prolonged the progression-free survival in patients treated with mFFX. The combination therapy of Peg G and mFFX may be recommended in patients who exhibit grade 3-4 neutropenic events after prior mFFX cycles. - Minaga Kosuke; Takenaka Mamoru; Yoshikawa Tomoe; Okamoto Ayana; Ishikawa Rei; Yamazaki Tomohiro; Nakai Atsushi; Omoto Shunsuke; Kamata Ken; Yamao Kentaro; Kudo MasatoshiGASTROINTESTINAL ENDOSCOPY 89 6 AB299 2019年06月 [査読有り]
- Tomohiro Yamazaki; Hitoshi OhnoInternal medicine (Tokyo, Japan) 50 21 2659 - 62 2011年A 50-year-old man presented with an ileocecal tumor and a large amount of ascites. Lymphoma cells obtained from the ascitic fluid were CD10(+), CD20(+), CD38(+), HLA-DR(+), BCL6(-), MUM1/IRF4(+), BCL2(+), and immunoglobulin µ/γ(+). The karyotype determined by G-banding and spectral karyotyping was 46, XY, der(3)t(1;3)(q12;p12), -4, +7, t(8;14)(q24;q32), t(12;14)(q24;q32), der(17)t(4;17)(q21;p11). Fluorescence in situ hybridization disclosed that 93% of interphase cells were positive for the c-MYC and immunoglobulin heavy chain gene fusion. The patient was treated with intensive chemo-immunotherapy, resulting in a complete response. The t(8;14)-t(12;14) double-hit may have generated molecular abnormalities analogous to those of a previously cloned three-way translocation t(8;12;14).