A large-scale study of the ultrawideband microwave dielectric properties of normal, benign and malignant breast tissues obtained from cancer surgeries

TLDR

Microwave breast cancer detection relies on contrast in dielectric properties between malignant and normal tissues, yet comprehensive, consistent data across frequencies remain scarce. This study experimentally measured ultrawideband microwave dielectric properties (0.5–20 GHz) of normal, benign, and malignant breast tissues from cancer surgeries. Using a precision open‑ended coaxial probe, we collected permittivity data from adipose, glandular, fibroconnective, ductal and lobular carcinomas, fibroadenomas, and cysts, and fitted a one‑pole Cole‑Cole model to each sample. The results reveal a large 10:1 contrast between malignant and normal adipose‑dominated tissues, whereas the contrast in glandular/fibroconnective tissues is only about 10 %.

Abstract

The development of microwave breast cancer detection and treatment techniques has been driven by reports of substantial contrast in the dielectric properties of malignant and normal breast tissues. However, definitive knowledge of the dielectric properties of normal and diseased breast tissues at microwave frequencies has been limited by gaps and discrepancies across previously published studies. To address these issues, we conducted a large-scale study to experimentally determine the ultrawideband microwave dielectric properties of a variety of normal, malignant and benign breast tissues, measured from 0.5 to 20 GHz using a precision open-ended coaxial probe. Previously, we reported the dielectric properties of normal breast tissue samples obtained from reduction surgeries. Here, we report the dielectric properties of normal (adipose, glandular and fibroconnective), malignant (invasive and non-invasive ductal and lobular carcinomas) and benign (fibroadenomas and cysts) breast tissue samples obtained from cancer surgeries. We fit a one-pole Cole-Cole model to the complex permittivity data set of each characterized sample. Our analyses show that the contrast in the microwave-frequency dielectric properties between malignant and normal adipose-dominated tissues in the breast is considerable, as large as 10:1, while the contrast in the microwave-frequency dielectric properties between malignant and normal glandular/fibroconnective tissues in the breast is no more than about 10%.