A clinicopathological base study to control over-diagnosis in early breast cancer screening and advance compound noninvasive immunotherapy for early breast cancer

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08707
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Human pathology
• Research Institution: Kurume University
• Principal Investigator: Yamaguchi Rin 久留米大学, 医学部, 准教授 (10309750)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 乳癌 / サブタイプ / 過剰診断 / HER2陽性 / 腫瘍浸潤リンパ球 / DCIS / コメド壊死 / 複合免疫療法

Outline of Final Research Achievements

Breast cancer (BC) is investigated from not only histological viewpoints, but also the subtypes. We examined how BC progresses from early (in situ) diagnosis to invasion by the subtypes (luminal, Her2, triple negative), as well from the histological viewpoint of the immune response to control over-diagnosis and over-treatment in early BC screening. In early BC, in situ Her2 BCs have high-grade cancer cells with comedo necrosis and there is a pathway of invasion by the response of tumor-infiltrating lymphocytes, which are different from other subtypes. Invasive Her2 BCs are revealed to divide largely into ER positive and negative depending on pathological, morphological, and immunological viewpoints. We believe that our results can contribute to the control of over-diagnosis and over-treatment in early BC screening and advance compound noninvasive immunotherapy for early BC.

Free Research Field

乳腺病理

Academic Significance and Societal Importance of the Research Achievements

高異型度上皮内乳癌が浸潤する際に免疫応答による経路が明らかになり、さらに通常高異型度癌が有するコメド壊死がマンモグラフィなど画像による石灰化に反映することから、元来予後不良であったHer2陽性や高異型度乳癌の早期発見に繋がることが示唆された。浸潤性Her2陽性乳癌ではER陽性と陰性群で病理・形態学的・免疫応答の点においてに大きく二分されることが明らかとなり、他サブタイプとの進展、浸潤の差異、類似点から、更なる早期発見や治療指針にも寄与できる。また、今後の複合免疫療法など新たなる治療にも繋がる。我々の研究結果は、目的とした検診の過剰診断抑制や今後の乳癌治療指針への大きな貢献を可能とする。