Development of a diagnostic imaging system to evaluate tumor heterogeneity and tumor infiltrating lymphocytes

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K10550
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General surgery
• Research Institution: Hiroshima University
• Principal Investigator: masumoto norio 広島大学, 病院(医), 助教 (40528014)
• Co-Investigator(Kenkyū-buntansha): 岡田 守人 広島大学, 原爆放射線医科学研究所, 教授 (70446045)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 腫瘍浸潤リンパ球 / 超音波画像装置 / 乳癌 / 乳房専用PET / 腫瘍内不均一性

Outline of Final Research Achievements

The SUVs of DbPET are highly correlated with prognostic clinicopathological factors. This methodology can be used to visualize not only homogenous but also heterogeneous intratumoral FDG distributions of breast cancer. Moreover, pathological images of cancers with heterogeneous intratumoral distributions confirm that invasive cancer is present at sites of strong FDG uptake, while sites with weak uptake are more likely to have necrosis and fibrosis. We conclude that the intratumoral heterogeneity on DbPET can predict the malignancy grade of breast cancer.
The presence of TILs is predictive of prognosis and therapeutic effect for breast cancer. Our method for determining the TILs-US score based on conventional US findings was found to be an accurate and convenient diagnostic method for LPBC and can be easily performed preoperatively. The clinical application of the TILs-US score in LPBC is expected to lead to a new treatment strategy for breast cancer.

Free Research Field

乳腺外科

Academic Significance and Societal Importance of the Research Achievements

腫瘍には、腫瘍内不均一性をはじめとした問題により、既存の評価法には限界があり、新たな評価法の確立が国際社会より望まれており喫緊の課題である。乳房専用PET（DbPET)による画像検査と病理像を比較検証することで、DbPETは腫瘍の不均一性を予測できること、そして腫瘍の増殖能や悪性度を予測できることを実証した。また腫瘍の予後予測因子である腫瘍浸潤リンパ球(TILs)を多く持つ腫瘍には、超音波検査で特徴的所見があることを同定した。そしてその特徴的超音波画所見を組み合わせることで、TILsを予測できることを実証した。