Ultrasound elastography as an imaging biomarker for detection of early tumour response to chemotherapy in a murine breast cancer model: a feasibility study.

Jian-Wei Wang, Zhi-Xing Guo, Qing-Guang Lin, Wei Zheng, Shu-Lian Zhuang, Shi-Yang Lin, An-Hua Li, Xiao-Qing Pei,

The British journal of radiology, November 30, -0001

This study investigated the feasibility of using strain elastography (SE) and real time shear wave elastography (RT-SWE) to evaluate early tumor response to cytotoxic chemotherapy in a murine xenograft breast cancer tumor model. MCF-7 breast cancer-bearing nude mice were treated with either cisplatin 2 mg/kg plus paclitaxel 10 mg/kg (treatment group) or sterile saline (control group) once daily for 5 days. The tumor elasticity was measured by SE or RT-SWE before and after therapy. Tumor cell density was assessed by hematoxylin and eosin staining, and the ratio of collagen fibers in the tumor was evaluated by Van Gieson staining. The correlation between tumor elasticity, as determined by SE and SWE, as well as the pathologic tumor responses were analyzed. Chemotherapy significantly attenuated tumor growth compared to the control treatment (p < 0.05). Chemotherapy also significantly increased tumor stiffness (p < 0.05) and significantly decreased (p < 0.05) tumor cell density compared with the control. Moreover, chemotherapy significantly increased the ratio of collagen fibers (p < 0.05). Tumor stiffness was positively correlated with the ratio of collagen fibers but negatively correlated with tumor cell density. The study suggests that ultrasound elastography (UE) by SE and SWE is a feasible tool for assessing early responses of breast cancer to chemotherapy in our murine xenograft model. Advances in knowledge: This study showed that the tumor elasticity determined by UE could be a feasible imaging biomarker for assessing very early therapeutic responses to chemotherapy.

Pubmed Link: 29400545

DOI: 10.1259/bjr.20170698