Updated on 2025/08/28

Information

 

写真a

 
SHIRAKAWA YUKO
 
Organization
Faculty of Medical Sciences Assistant Professor
Title
Assistant Professor
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Papers

  • Combination of Clinical Factors and Radiomics Can Predict Local Recurrence and Metastasis After Stereotactic Body Radiotherapy for Non-small Cell Lung Cancer Reviewed

    Isoyama-Shirakawa Y., Yoshitake T., Ninomiya K., Asai K., Matsumoto K., Shioyama Y., Kodama T., Ishigami K., Arimura H.

    Anticancer Research   43 ( 11 )   5003 - 5013   2023.11   ISSN:02507005

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    Authorship:Lead author   Publisher:Anticancer Research  

    Background/Aim: Radiomics, which links radiological image features with patient prognoses, is expected to be applied for the prediction of the clinical outcomes of radiotherapy. We investigated the clinical and radiomic factors associated with recurrence patterns after stereotactic body radiotherapy (SBRT) for non-small cell lung cancer (NSCLC). Patients and Methods: We retrospectively analyzed 125 patients with histologically confirmed NSCLC who underwent SBRT between April 2003 and June 2017 at our institution. A radiomic score was calculated from five radiomics features (histogram and texture features) selected using the LASSO Cox regression model. These features were extracted from the gross tumor volume (GTV) in three-dimensional wavelet decomposition CT images. We used univariate and multivariate analyses to determine the associations between local control (LC) time and metastasis-free survival (MFS), clinical factors (age, sex, performance status, operability, smoking, histology, and tumor diameter), and the radiomic score. Results: With a median follow-up of 37 months, the following 3-year rates were observed: overall survival, 80.9%; progression-free survival, 61.7%; LC, 75.1%, and MFS; 74.5%. In multivariate analysis, histology (squamous cell carcinoma vs. non-squamous cell carcinoma, p=0.0045), tumor diameter (>3 cm vs. ≤3 cm, p=0.039); and radiomic score (>0.043 vs. ≤0.043, p=0.042) were significantly associated with LC, and the radiomic score (>0.304 vs. ≤0.304, p<0.001) was significantly associated with MFS. Conclusion: Histology, tumor diameter, and radiomic score could be significant factors for predicting NSCLC recurrence patterns after SBRT.

    DOI: 10.21873/anticanres.16699

    Scopus

  • Dosimetric evaluation of cone beam computed tomography-guided online adaptive radiotherapy in gastric mucosa-associated lymphoid tissue lymphoma

    Takaki, M; Hirose, TA; Yoshitake, T; Matsumoto, K; Shirakawa, Y; Wakiyama, H; Hisano, O; Imafuku, H; Ishigami, K

    TECHNICAL INNOVATIONS & PATIENT SUPPORT IN RADIATION ONCOLOGY   35   100321   2025.9   eISSN:2405-6324

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    Language:English   Publisher:Technical Innovations and Patient Support in Radiation Oncology  

    Introduction: This study evaluated dosimetric values of cone beam computed tomography (CBCT)-guided online adaptive radiotherapy (oART) in patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma, accounting for interfractional and intrafractional motion. Methods: Four patients with stage I gastric MALT lymphoma received CBCT-guided oART. For each of the 60 treatment sessions, scheduled (SCH) and adapted (ADP) plans were generated. Dosimetric evaluation focused on clinical target volume (CTV) and organs at risk (OARs). Metrics included CTV D98 % and D95 %, mean dose to the liver and left and right kidneys, maximum dose to the spinal cord, and V5Gy for bilateral kidneys. Adaptive planning CBCT-based contours were propagated to synthetic CTs of SCH and ADP plans to assess interfractional motion. Post-treatment CBCT-based contours were propagated to synthetic CTs of the ADP plan to evaluate intrafractional motion. Results: ADP plans significantly improved CTV coverage: mean D98% increased from 94.7 % in the SCH plan to 98.6 %, and D95% from 97.3 % to 99.2 % (p < 0.001). Most OAR doses were reduced in the ADP plans, including bilateral kidney V5Gy (11.3 % vs. 8.3 %, p < 0.001) and spinal cord Dmax (9.8 Gy vs. 7.9 Gy, p < 0.001). Liver Dmean was slightly higher in the ADP plan (11.4 Gy vs. 11.1 Gy, p = 0.002). No significant differences were observed in CTV and OAR dosimetric parameters between adaptive planning and post-treatment CBCTs (e.g., CTV D98%: 98.6 % vs. 98.5 %, p = 0.629). Conclusion: CBCT-guided oART improved target coverage and maintained post-treatment dosimetric stability in gastric MALT lymphoma, supporting clinical feasibility.

    DOI: 10.1016/j.tipsro.2025.100321

    Web of Science

    Scopus

    PubMed

  • Time-variant tumor growth trajectory models for in silico randomized controlled trials for patients with early-stage non-small cell lung cancer in optimizing stereotactic body radiation therapy

    Mitsushima, K; Arimura, H; Shirakawa, Y; Kodama, T; Yoshitake, T

    HEALTH AND TECHNOLOGY   2025.8   ISSN:2190-7188 eISSN:2190-7196

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    Publisher:Health and Technology  

    Purpose: Applying new treatments to real patients to verify therapeutic efficacy may induce various risks, such as critical adverse events. Additionally, there are ethical and financial issues in real-world randomized controlled trials (RCTs). This study aimed to develop mathematical models of time-variant tumor growth trajectories (TGTs) for in silico RCTs targeting patients with stage I non-small cell lung cancer (NSCLC) to optimize stereotactic body radiation therapy (SBRT). Methods: The basic idea of the in silico RCT was to evaluate the endpoint of progression-free survival (PFS) curves for the two regimens derived from TGTs for virtual patient data produced via mathematical models. TGT models with a relative number of tumor cells were proposed by integrating the Bertalanffy-Pütter (BP) model and linear quadratic model into tumor growth models. To validate the proposed models, we performed three RCTs, 30 Gy/1 fraction (Fr) versus 60 Gy/3 Fr, 48 Gy/4 Fr versus 75 Gy/25 Fr, and 34 Gy/1 Fr versus 48 Gy/4 Fr. Results: The three in silico RCTs showed no statistically significant differences in PFS curves, which was similar to the results of three previous studies. Conclusions: The proposed mathematical models could be leveraged for in silico RCTs to optimize SBRT.

    DOI: 10.1007/s12553-025-01005-2

    Web of Science

    Scopus

  • 体幹部定位放射線治療を受けた早期非小細胞肺癌患者における腫瘍成長モデルの開発

    光島 千稀, 有村 秀孝, 白川 友子, 吉武 忠正

    日本医用画像工学会大会予稿集   43回   134 - 135   2024.8

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    Language:Japanese   Publisher:(一社)日本医用画像工学会  

    体幹部定位放射線治療(SBRT)を受けた早期非小細胞肺癌(NSCLC)患者では腫瘍が進行することがある.したがって,本研究では腫瘍の進行予測を目的とし,SBRTを受けた早期NSCLC患者の腫瘍成長モデルの開発を行った.SBRTを施行したNSCLC患者17名を選択し,治療前後のCT画像から輪郭描出した肉眼的腫瘍体積(GTV)をもとに腫瘍細胞数を算出し,それらを参照値とした.一方,放射線に対して3つの異なる反応を示す細胞集団(感受性細胞,persister細胞,抵抗性細胞)が存在すると仮定し,Gompertzモデルに基づいた腫瘍成長モデルを構築した.腫瘍成長モデルに含まれる9つのパラメータを焼きなまし法によって最適化し,腫瘍細胞数の経時変化曲線を推定した.SBRTを受けた早期NSCLC患者において,腫瘍細胞数の予測可能性を示したが,進行予測のためには腫瘍成長モデルの更なる改良が必要である.(著者抄録)

  • 肺がん定位体放射線治療における3次元計画CT画像上のGTVに対する深層学習ネットワークのセグメンテーション性能への訓練対テスト比の影響(Impact of training-to-test number ratio on segmentation performance of deep learning networks for gross tumor volumes on 3D planning computed tomography images in lung cancer stereotactic body radiotherapy)

    崔 雲昊, 有村 秀孝, 白川 友子, 吉武 忠正, 塩山 善之, 藪内 英剛

    日本医用画像工学会大会予稿集   42回   130 - 131   2023.7

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    Language:English   Publisher:(一社)日本医用画像工学会  

    我々は深層学習(DL)を用いて体幹部定位放射線治療(SBRT)の治療計画CT画像において肺腫瘍の領域抽出法を研究している。SBRTにおいて領域抽出性能は訓練データ数に依存するが、その性能をある程度維持できる訓練データ数は研究されていない。本研究では、訓練データ数対テストデータ数比(training-to-test number ratio:TTR)の腫瘍領域抽出性能に対する影響を調査した。本研究は、非小細胞肺癌患者192名[solid:118名、part-solid:53名、ground-glass opacity(GGO):21名]を対象とした。3D U-Net、V-Net、およびDense V-Netの3つのDLモデルを5パターンのTTR(1.00、0.791、0.531、0.291および0.116)でトレーニングした。3つのモデルは、Dice係数、precision、およびrecallに基づいて評価された。V-Netは、TTR=0.116のとき、最も高い0.788のDice係数を達成し、precisionは0.826、recallは0.794であった。訓練症例が10%、検証症例が5%に削減されても、ある程度領域抽出性能を維持できる可能性を示した。(著者抄録)

  • Relapse predictability of topological signature on pretreatment planning CT images of stage I non-small cell lung cancer patients before treatment with stereotactic ablative radiotherapy

    Kodama, T; Arimura, H; Shirakawa, Y; Ninomiya, K; Yoshitake, T; Shioyama, Y

    THORACIC CANCER   13 ( 15 )   2117 - 2126   2022.8   ISSN:1759-7706 eISSN:1759-7714

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    Language:English   Publisher:Thoracic Cancer  

    Background: This study aimed to explore the predictability of topological signatures linked to the locoregional relapse (LRR) and distant metastasis (DM) on pretreatment planning computed tomography images of stage I non-small cell lung cancer (NSCLC) patients before treatment with stereotactic ablative radiotherapy (SABR). Methods: We divided 125 primary stage I NSCLC patients (LRR: 34, DM: 22) into training (n = 60) and test datasets (n = 65), and the training dataset was augmented to 260 cases using a synthetic minority oversampling technique. The relapse predictabilities of the conventional wavelet-based features (WF), topology-based features [BF, Betti number (BN) map features; iBF, inverted BN map features], and their combined features (BWF, iBWF) were compared. The patients were stratified into high-risk and low-risk groups using the medians of the radiomics scores in the training dataset. Results: For the LRR in the test, the iBF, iBWF, and WF showed statistically significant differences (p < 0.05), and the highest nLPC was obtained for the iBF. For the DM in the test, the iBWF showed a significant difference and the highest nLPC. Conclusion: The iBF indicated the potential of improving the LRR and DM prediction of stage I NSCLC patients prior to undergoing SABR.

    DOI: 10.1111/1759-7714.14483

    Web of Science

    Scopus

    PubMed

  • 治療計画CT画像のトポロジー解析によるレディオミクスシグネチャを用いた体幹部定位放射線治療を受けたステージI非小細胞肺癌患者の進行予測

    兒玉 拓巳, 有村 秀孝, 白川 友子, 二宮 健太, 吉武 忠正, 塩山 善之

    日本医用画像工学会大会予稿集   41回   152 - 153   2022.7

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    Language:Japanese   Publisher:(一社)日本医用画像工学会  

    早期非小細胞肺癌(NSCLC)の標準治療は手術と体幹部定位放射線治療(SABR)で,両者の治療効果は同等であり,治療前の再発リスク予測により患者毎の適切な治療法選択を実現する可能性がある.本研究の目的は,SABRの治療前計画CT画像のトポロジー解析による画像シグネチャを用いてステージI期NSCLC患者の治療後の癌進行を予測することである.患者群をレディオミクススコア(Rad-score)により高・低リスク群に分類し,p値(log-rank test),c-index,総合指標のnLPCを用いて評価した.Rad-scoreは,従来ウェーブレット特徴量(WFs)及びトポロジー解析に基づくベッチ数マップから得た特徴量(TFs)を基にCox-netにより構築したシグネチャから計算された.テスト症例のp値,c-index,nLPCはそれぞれ,TFsで3.28×10^-2,0.80,1.19,WFsで3.13×10^-2,0.72,1.08であった.TFsはWFsと比較しより有意なNSCLCの進行との関連性を持つ可能性がある.(著者抄録)

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Presentations

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Research Projects

  • Prediction system for severity of pneumonitis after radiotherapy for lung cancer and optimization of treatment methods using deep learning

    Grant number:20K08113  2020.4 - 2024.3

    Grants-in-Aid for Scientific Research  Grant-in-Aid for Scientific Research (C)

    Shioyama Yoshiyuki

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    Grant type:Scientific research funding

    We performed to developed a prediction model of RP using CT imaging features for stereotactic radiotherapy of early-stage lung cancer and showed the usefulness of combining serum KL-6, a marker of interstitial pneumonia, with CT imaging features.
    We also showed that CT imaging features can predict the risk of recurrence after stereotactic radiotherapy. Furthermore, we examined whether the combined use of radiomics score and various clinical factors (age, gender, PS, histological type, tumor size, etc.) can predict the risk of local recurrence and distant metastasis more accurately. The results suggest that the risk of recurrence and its pattern (local recurrence, distant metastasis) after stereotactic irradiation of lung cancer can be predicted by using the radiomic score in addition to the histological type and tumor size.

    CiNii Research