2023 Fiscal Year Final Research Report

Non operative approach for breast cancer by therapy-induced tumor dormancy

Research Project

PDF

Project/Area Number	18K08585
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 55010:General surgery and pediatric surgery-related
Research Institution	Hiroshima University (2023) Department of Clinical Research, National Hospital Organization Kure Medical Center (2018-2022)
Principal Investigator	Shigematsu Hideo 広島大学, 原爆放射線医科学研究所, 講師 (40543707)
Co-Investigator(Kenkyū-buntansha)	尾崎慎治独立行政法人国立病院機構(呉医療センター臨床研究部), その他部局等, その他 (10558266)
Project Period (FY)	2018-04-01 – 2024-03-31
Keywords	Breast Cancer / Peritumoral edema / Neoadjuvant chemotherapy / Relapse free survival / Overall survival
Outline of Final Research Achievements	To elucidate the mechanism of dormancy induction by breast cancer drug therapy, we investigated the correlation between tumor microenvironment factors and prognosis in early-stage breast cancer patients treated with neoadjuvant chemotherapy. Focusing on peritumoral edema (PE) as a key microenvironmental factor, we conducted clinical and basic research. Among 128 early-stage breast cancer cases treated with neoadjuvant chemotherapy, 64 were positive for PE, with residual PE observed in 22 cases. Residual PE was identified as a significant adverse prognostic factor for recurrence-free survival and overall survival. Furthermore, an increased tendency of tumor-associated immune cells was noted in cancers with residual PE. These findings suggest that PE may serve as an adverse prognostic marker and a potential therapeutic target in early-stage breast cancer.
Free Research Field	Breast Cancer
Academic Significance and Societal Importance of the Research Achievements	早期乳癌に対する術前化学療法は標準治療として施行される。術前化学療法後に病変遺残を認めた乳癌（no pCR）の予後は極めて不良であり、no pCR乳癌に対する治療戦略の開発は喫緊の課題である。本研究では術前化学療法が施行された乳癌を対象に乳房MRIにより腫瘍微小環境として腫瘍周囲浮腫（PE）を評価し、PE遺残が有意な予後不良因子であることを示した。PE遺残は腫瘍関連免疫細胞との相関が示唆され、腫瘍免疫細胞を標的とした治療がno pCR乳癌の予後改善に寄与することが期待される。本研究結果は、腫瘍微小環境を標的とした新たな治療戦略を提起し、no pCR乳癌の予後改善に寄与することが期待される。