Clinical value of plasma cfDNA concentration and integrity in breast cancer patients

Breast cancer is a malignant tumor that occurs in the glandular epithelial tissues of the breast. It is one of the most common malignant tumors in women. This study was aimed at investigating the role of cell-free DNA (cfDNA) as a potential biomarker for breast cancer diagnosis. Patients with primary breast cancer (n =110) were enrolled in the experimental group, 95 patients with benign breast tumors were in control group 1, while 90 healthy volunteers were in control group 2. Quantitative PCR was used to determine cfDNA concentration and integrity in each group. The cfDNA levels in different groups and their relationship with clinical features of breast cancer patients were analyzed. Receiver operational curves were established to analyze sensitivity and specificity of cfDNA concentration, cfDNA integrity, CEA, CA125 and CA15-3. The cfDNA concentration and cfDNA integrity of the experimental group were significantly higher than those of control groups 1 and 2. The cfDNA concentration and integrity in plasma of experimental group after chemotherapy were significantly lower than those before chemotherapy. While CEA and CA15-3 expressions were significantly correlated with cfDNA concentration, CA125 expression was significantly correlated with cfDNA integrity. Results from ROC curve analysis showed that the sensitivity and specificity of cfDNA concentration and integrity were higher than those of traditional tumor biomarkers. These results indicate that cfDNA concentration and integrity are significantly higher in primary breast cancer patients than in benign breast tumor patients and healthy people. Thus, cfDNA may serve as a potential biomarker of breast cancer.