Content area
Full text
Introduction
Breast cancer, a common malignancy worldwide, remains a global public health problem. The Global Cancer Burden data estimates that in 2020 there were 2.26 million new cases of breast cancer (1). Mass-type breast cancer is a typical feature of breast cancer (2). However, owing to negligence in breast self-examination and clinical examination, patients continue to be diagnosed at an advanced stage of disease (3). Previous and ongoing research has had significant implications for improving the clinical outcomes of breast cancer owing to the progress achieved in the fields of screening, diagnosis and therapeutic strategies for breast cancer management (4). Lifestyle and environmental factors (lack of physical exercise, alcohol consumption and high-fat diet) affect the development of breast cancer, the appropriate management of which could result in a reduction in morbidity and mortality. Other diagnostic tests, such as mammography, ultrasonography, breast self-examination and magnetic resonance imaging, aid in the early detection of tumors (5). Recently, there has been significant improvement in the speed and resolution of image acquisition; however, imaging-based diagnosis is restricted by subjective factors, such as the experience and ability of clinicians, and their capability to reproduce results and promote screening (6).
The formation of new blood vessels, reduction in blood flow resistance and elevation of blood flow in breast cancer lesions form the basis of cancer cell growth. Thus, an accurate estimation of blood flow status in tumor lesions can provide a basis for determining malignancy (7). In breast imaging examinations, ultrasound has become the first choice for physicians and patients owing to its simplicity, economy, effectiveness, convenience and safety (8). Doppler ultrasound is a common approach for evaluating blood flow status in clinical practice, and the evaluation of blood flow parameters can quantify blood flow in local tissues (9). Color Doppler ultrasound is a promising alternative for assessing tumor responses in breast cancer due to its availability, reproducibility and cost-effectiveness (10).
Additionally, with increases in healthcare costs and the introduction of novel targeted therapies, the application of biomarkers has become an approach to assist in cancer diagnosis, prognosis, treatment response prediction, and disease monitoring during and after treatment (11). Cancer antigen 15-3 (CA15-3) is a tumor protein in a variety of cancer types, particularly breast cancer (12). CA15-3 levels in breast...