Potential of Liquid Biopsies for Breast Cancer Screening, Diagnosis, and Response to Treatment

Abstract

Cancer therapy decisions are often made according to the histopathological-molecular profile of tumor tissue obtained from surgery or biopsy. It has been shown that tumor profiles change with time and treatment, and that tumor tissue is heterogeneous. Thus, other approaches that are easily accessible and less invasive than surgery or biopsy to monitor responses to treatment and predict relapses are urgently needed. In the last few years, the term “liquid biopsies” has been introduced to represent multifunctional circulating biomarkers in the peripheral blood and other physiological fluids of patients with cancer. Liquid biopsies are a noninvasive alternative to tissue biopsies, but they have not been implemented in routine clinical practice for breast cancer. In addition, liquid biopsies seem to be a promising approach for personalized medicine, which enables the prediction, monitoring, and rational selection of appropriate therapy for individual patients. In this review, we outline recent progress and current challenges with liquid biopsies in clinical practice for breast cancer diagnosis, treatment choices, and responses to therapy from a clinician’s perspective.

Association of Circulating Tumor DNA With Disease-Free Survival in Breast Cancer

“…as TP53, PIK3CA, and ERBB2 in breast cancer. 34 Five of the studies included in the present study used PCR techniques to measure ctDNA gene variants. 18,[20][21][22][23] rence and the degree of benefit associated with chemotherapy.…”

Targeted Next-Generation Sequencing of Circulating Tumor DNA Mutations among Metastatic Breast Cancer Patients

“…The application of ctDNA-based real-time liquid biopsy represents a noninvasive and highly sensitive biomarker for cancer diagnosis, early prediction, and therapeutic response assessment [7,[19][20][21][22]. Although there have been many studies regarding ctDNA and breast cancer, some challenges and limitations remain for its clinical implementation, including the identi cation of speci c driver mutations for the multiple demands of breast cancer management, the high costs of detecting the low proportion of ctDNA in the "sea" of normal DNA, and the development of standardized methods for data processing [12,23,24].The development of NGS and bioinformatics has provided new opportunities for the establishment and validation of speci c panels of mutation biomarkers for routine clinical use in breast cancer management [25,26].…”

Non-Invasive Biomarkers for Early Detection of Breast Cancer

“…Compared with carcinoma proteins and CTCs, ctDNA has several advantages, being a better and more sensitive marker for monitoring tumor burden [ 107 , 108 ]. It has a greater dynamic range representing the heterogenetic features of tumors, a shorter half-life, and is more specific to malignancy [ 109 ].…”