Tamura, Masashi



School of Medicine, Department of Radiology (Diagnostic Radiology) (Shinanomachi)




Papers 【 Display / hide

  • Development of human hepatocellular carcinoma in X-linked severe combined immunodeficient pigs: An orthotopic xenograft model

    Mishima K., Itano O., Matsuda S., Suzuki S., Onishi A., Tamura M., Inoue M., Abe Y., Yagi H., Hibi T., Kitago M., Shinoda M., Kitagawa Y.

    PLoS ONE (PLoS ONE)  16 ( 3 March ) e0248352 2021.03

     View Summary

    Hepatocellular carcinoma (HCC) is the fifth most common primary tumor and the third leading cause of cancer-related deaths worldwide. Rodent models of HCC have contributed to the advancement of studies investigating liver carcinogenesis, tumor-host interactions, and drug screening. However, their small size renders them unsuitable for surgical or clinical imaging studies, necessitating the development of larger-size HCC models. Here, we developed a xenograft model of human HCC in X-linked interleukin-2 receptor gamma chain gene (Il2rg)-targeted severe combined immunodeficient (SCID) pigs. HepG2 cell suspension in serum-free medium containing 50% membrane matrix was directly injected into the liver parenchyma of eight X-linked Il2rg-targeted SCID pigs (6.6-15.6 kg) via ultrasonography- guided percutaneous puncture. Tumor engraftment was evaluated weekly using ultrasonography, and cone-beam computed tomography was performed during arterial portography (CTAP) and hepatic arteriography (CTHA) to evaluate the hemodynamics of engrafted tumors. The engrafted tumors were histologically analyzed following necropsy and assessed for pathological similarities to human HCCs. Macroscopic tumor formation was observed in seven of the eight pigs (simple nodular tumors in three and multinodular tumors in four). Engrafted tumors were identified as low-echoic upon ultrasonography and as perfusion-defect nodules on the CTAP images. Meanwhile, CTHA showed that the tumors were hyperattenuating. Further, histopathological findings of the engrafted tumors were consistent with those of human HCC. In conclusion, the porcine model of human HCC, successfully generated herein, might help develop more effective therapeutic strategies for HCC.

  • Arteriovenous malformation on the sole of the foot treated successfully by embolization

    Yuzaki I., Aramaki-Hattori N., Tamura M., Torikai H., Okabe K., Sakai S., Nakatsuka S., Jinzaki M., Kishi K., Inoue M.

    Radiology Case Reports (Radiology Case Reports)  15 ( 12 ) 2621 - 2626 2020.12

     View Summary

    © 2020 Arteriovenous malformations of the sole of the foot are rare and can cause disturbances in normal living activities. We report a case of a plantar arteriovenous malformation in a 24-year-old male with pain and difficulty in walking. The arteriovenous malformation was complex, with a large and poorly marginated nidus, so we considered that with surgical resection, walking disabilities would be inevitable. When surgical removal of vascular mass is difficult, embolization alone can be effective. Therefore, he was treated with 4 therapeutic embolization procedures. Transvenous approaches to the venous sac and direct punctures of the nidus was performed. The nidus was successfully eradicated by embolization using alcohol, resulting in the disappearance of associated symptoms. Appropriate imaging is essential for diagnosis and evaluation of treatment. We were successful in achieving improved quality of life and satisfaction for a rare and difficult case by percutaneous embolization and sclerotherapy.

  • Predictors of Occlusion of Hepatic Blood Vessels after Irreversible Electroporation of Liver Tumors

    Tamura M., Pedersoli F., Schulze-Hagen M., Zimmerman M., Isfort P., Kuhl C.K., Schmitz-Rode T., Bruners P.

    Journal of Vascular and Interventional Radiology (Journal of Vascular and Interventional Radiology)  31 ( 12 ) 2033 - 2042.e1 2020.12

    ISSN  10510443

     View Summary

    © 2020 SIR Purpose: To examine predictors of midterm occlusion in portal and hepatic veins within or adjacent to the ablation zone after irreversible electroporation (IRE) of liver tumors. Materials and Methods: This retrospective cohort analysis included 39 patients who underwent CT-guided IRE of liver tumors. Vessels within or adjacent to the ablation zone were identified on CT images acquired immediately after the procedure, and the positional relationships with the ablation zone (within/adjacent), locations (proximal/distal), and diameters (< 4 mm or ≥ 4 mm) were evaluated. Using contrast-enhanced follow-up scans, each vessel was classified as patent, stenosed, or occluded. Associations between vessel occlusion and each variable were investigated. Results: Overall, 33 portal veins and 64 hepatic veins were analyzed. Follow-up scans showed occlusion in 12/33 (36.7%) portal veins and 17/64 (26.6%) hepatic veins. Vessels within the ablation zone were occluded significantly more frequently than vessels adjacent to the ablation zone (portal: 55.6% [10/18] vs 13.3% [2/15], P = .04; hepatic: 45.4% [15/33] vs 6.4% [2/31], P = .011). Vessels with a diameter < 4 mm were also occluded significantly more frequently than vessels with a diameter ≥ 4 mm (portal: 72.7% [8/11] vs 18.1% [4/22], P = .011; hepatic: 54.8% [17/31] vs 0% [0/33], P < .001). The respective positive and negative predictive values for occlusion of vessels categorized as both within and < 4 mm were 88% (7/8) and 82% (20/25) for portal veins and 79% (15/19) and 96% (43/45) for hepatic veins. Conclusions: Midterm vessel occlusion after liver IRE could be predicted with relatively high accuracy by assessing ablation location and vessel diameter.

  • Successful depiction of systemic collateral supply to pulmonary artery in CTEPH using time-resolved 4D CT angiography: a case report

    Tamura M., Kawakami T., Yamada Y., Kataoka M., Nakatsuka S., Fukuda K., Jinzaki M.

    Pulmonary Circulation (Pulmonary Circulation)  10 ( 2 ) 2045894019881065 2020

    ISSN  20458932

     View Summary

    © The Author(s) 2020. A 49-year-old man with CTEPH (pre-procedural mean pulmonary artery pressure: 36 mmHg) underwent balloon pulmonary angioplasty. Chronic total occlusion of the left inferior pulmonary artery trunk was observed. To evaluate the collateral vessels of the chronic total occlusion, 4D-CTA was performed. The examination was performed using a 256-row detector CT system using the test bolus tracking method. 4D-CTA showed the bronchial artery-to-left inferior pulmonary artery collateral supply, which was confirmed by a selective bronchial artery angiography. The patient’s symptoms improved with balloon pulmonary angioplasty of the other stenotic lesions. 4D-CTA can noninvasively evaluate the anatomy and hemodynamics of multiple systemic collaterals simultaneously. This technique can support interventions in systemic artery-to-pulmonary artery collaterals, such as embolization, and could be helpful in challenging balloon pulmonary angioplasty interventions for chronic total occlusion to identify vessel structures distal to the chronic total occlusion and collateral channels for a retrograde approach.

  • Imaging Findings of Atypical Type II Endoleak Through Vasa Vasorum After Abdominal Endovascular Aneurysm Repair

    Torikai H., Inoue M., Nakatsuka S., Tamura M., Yashiro H., Yoshitake A., Shimizu H., Jinzaki M.

    CardioVascular and Interventional Radiology (CardioVascular and Interventional Radiology)  41 ( 1 ) 186 - 190 2018.01

    ISSN  01741551

     View Summary

    © 2017, Springer Science+Business Media, LLC and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE). A type II endoleak (T2EL) is the most common endoleak after endovascular aneurysm repair (EVAR), and a persistent T2EL has been occasionally associated with aneurysmal enlargement. Typical findings of a T2EL consist of an endoleak cavity with inflow and outflow arteries of aortic branch vessels. However, an atypical T2EL, in which hypertrophied vasa vasorum and enlargement of a thrombosed aneurysm are observed, has no endoleak cavity. We have seen three cases of continuous aortic aneurysmal growth after EVAR caused by atypical T2ELs without endoleak cavities through developed vasa vasorum. In this report, the imaging findings of selective angiography and dynamic computed tomography of these cases are reviewed.

display all >>

Reviews, Commentaries, etc. 【 Display / hide

  • 【Q&Aでまとめる! 予後予測・治療効果予測の画像検査】胸部(呼吸器・循環器・乳腺) 慢性血栓塞栓性肺高血圧症の画像的予後因子は何か?

    奥田 茂男, 田村 全, 山田 祥岳, 岩渕 雄, 松本 俊亮, 川上 崇史, 陣崎 雅弘

    臨床放射線 (金原出版(株))  65 ( 8 ) 847 - 857 2020.08

    ISSN  0009-9252

  • 当院におけるup-to-seven out、Child Pugh A HCCのTACE後のALBI scoreの推移

    小川 遼, 中塚 誠之, 長谷 学, 鳥飼 秀幸, 田村 全, 伊東 伸剛, 井上 政則, 屋代 英樹, 陣崎 雅弘

    日本インターベンショナルラジオロジー学会雑誌 ((一社)日本インターベンショナルラジオロジー学会)  35 ( Suppl. ) 193 - 193 2020.08

    ISSN  1340-4520

  • 【リンパ系のIVR】腹部リンパ漏病変に対するIVR

    井上 政則, 鳥飼 秀幸, 伊東 伸剛, 田村 全, 小川 遼, 中塚 誠之, 陣崎 雅弘

    日本インターベンショナルラジオロジー学会雑誌 ((一社)日本インターベンショナルラジオロジー学会)  34 ( 3 ) 187 - 192 2020.02

    ISSN  1340-4520

  • 【循環器疾患の画像診断-現状と進歩】肺循環疾患 CT angiographyおよびCT perfusionを活用する

    田村 全, 杉浦 弘明, 山田 祥岳, 川上 崇史, 陣崎 雅弘

    循環器ジャーナル ((株)医学書院)  67 ( 3 ) 410 - 419 2019.07

    ISSN  2432-3284

     View Summary

    <文献概要>Point ・肺循環疾患の画像診断は従来肺血管造影,シンチグラフィによって行われてきたが,多列化・高速化によるCT angiographyの画質向上やDual Energy CTやsubtraction技術によるCT perfusionの日常臨床導入により,CTの役割は大きくなってきている.・CTは肺高血圧症診療においてスクリーニングから分類,CT perfusionを利用した重症度評価・治療効果判定にまで広く用いることができるが,特に慢性血栓塞栓性肺高血圧症(CTEPH)を確実に拾い上げることが非常に重要である.・CT perfusionでは従来の肺血流シンチグラフィに比べて短時間で空間分解能の高い血流画像を取得することが可能であり,最近ではCTEPHにおける肺血流評価においても肺血流シンチグラフィとほぼ同等の成績が報告されている.

  • 先天性門脈体循環シャントの3例

    古後 斗冴, 中塚 誠之, 吉川 裕紀, 長谷 学, 鳥飼 秀幸, 田村 全, 伊藤 伸剛, 井上 政則, 陣崎 雅弘

    日本インターベンショナルラジオロジー学会雑誌 ((一社)日本インターベンショナルラジオロジー学会)  34 ( Suppl. ) 269 - 269 2019.05

    ISSN  1340-4520

display all >>

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

  • 超選択的副腎静脈支脈採血の普及・成功率上昇のための深層学習を用いた新規AI開発


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

  • 免疫不全豚を用いた肝癌新規実験モデルにおける血流動態/画像-病理相関の妥当性検討


    MEXT,JSPS, Grant-in-Aid for Scientific Research, Grant-in-Aid for Young Scientists (B), Principal investigator


Courses Taught 【 Display / hide