Microwave Imaging for Early Breast Cancer Detection: Current State, Challenges, and Future Directions

Abstract

Breast cancer is the most commonly diagnosed cancer type and is the leading cause of cancer-related death among females worldwide. Breast screening and early detection are currently the most successful approaches for the management and treatment of this disease. Several imaging modalities are currently utilized for detecting breast cancer, of which microwave imaging (MWI) is gaining quite a lot of attention as a promising diagnostic tool for early breast cancer detection. MWI is a noninvasive, relatively inexpensive, fast, convenient, and safe screening tool. The purpose of this paper is to provide an up-to-date survey of the principles, developments, and current research status of MWI for breast cancer detection. This paper is structured into two sections; the first is an overview of current MWI techniques used for detecting breast cancer, followed by an explanation of the working principle behind MWI and its various types, namely, microwave tomography and radar-based imaging. In the second section, a review of the initial experiments along with more recent studies on the use of MWI for breast cancer detection is presented. Furthermore, the paper summarizes the challenges facing MWI as a breast cancer detection tool and provides future research directions. On the whole, MWI has proven its potential as a screening tool for breast cancer detection, both as a standalone or complementary technique. However, there are a few challenges that need to be addressed to unlock the full potential of this imaging modality and translate it to clinical settings.

Keywords: breast cancer; breast tissues electrical properties; microwave breast imaging; microwave tomography; passive radiometry; radar-based imaging.

Figure 1

Citations of publications on the use of MWI in breast cancer screening applications from the Web of Science databases. Citations are presented: (a) per year; (b) per discipline.

Figure 2

Methods of microwave breast imaging. The figures on the left show (a) passive versus (b) active approaches. The figures on the right show patient’s orientations for (c) planar systems (supine position) versus (d) cylindrical systems (prone position).

Figure 3

Citations of publications on the use of MWT in breast cancer screening applications from the Web of Science databases. Citations are presented: (a) per year; (b) per discipline.

Figure 4

(a) MWT multi-frequency prototype; (b) typical phantom experiment with liquid containers suspended from above the tank and integrated with an alignment fixture for accurate positioning. Reprinted with permission from [38].

Figure 5

Citations of publications on the use of radar-based MWI in breast cancer screening applications from the Web of Science databases. Citations are presented: (a) per year; (b) per discipline.

Figure 6

UWB radar for breast cancer detection setup developed by the University of Bristol team. Reprinted with permission from [46].