Abstract:

Objective To investigate the roles of plasma cell-free deoxyribonucleic acid（cfDNA）levels and its integrity in the diagnosis and prognosis of breast cancer. Methods Plasma samples were collected from 106 patients newly diagnosed as breast cancer,72 breast benign disease patients and 301 healthy subjects. Plasma cfDNA was extracted,and then 100 bp and 241 bp human telomerase reverse transcriptases（hTERT）were quantified by real-time fluorescence quantitation polymerase chain reaction（PCR）. The cfDNA integrity was calculated,and the difference among the 3 groups and the relationship with tumor burden were analyzed. The sensitivities and specificities of 100 bp and 241 bp hTERT levels and cfDNA integrity for the diagnosis of breast cancer were evaluated by receiver operating characteristic（ROC）curve. Results The levels of 100 bp and 241 bp hTERT in breast cancer patients were higher than those in breast benign disease patients and healthy subjects（P<0.001）. The integrity of cfDNA was related to lymph node metastasis（P<0.01）. The areas under ROC curves （AUC）of 100 bp and 241 bp hTERT levels and cfDNA integrity were 0.693,0.792 and 0.865. The sensitivities were 73.3%,68.0% and 66.7%,and the specificities were 68%,80% and 92%,respectively. Conclusions The determinations of cfDNA levels and its integrity have certain clinical significance in the diagnosis and treatment of breast cancer,which could be as tumor biomarkers for the diagnosis and prognosis of breast cancer.

Key words: Breast cancer, Human telomerase reverse transcriptase, Cell-free deoxyribonucleic acid, Integrity