Detection and clinical significance of peripheral blood micrometastasis in patients with breast cancer

OBJECTIVE:To study the relationship between expression of human mammoglobin (hMAM) mRNA and biological characteristics of breast cancer and evaluate its clinical significance. METHODS: Expression of hMAM mRNA was detected in peripheral blood from patients with breast cancer and breast benign lesions, and healthy volunteers by the nested reverse transcriptase polymerase chain reaction (nested-RT-PCR). RESULTS: hMAM mRNA was found in 34 of 67 (50.75%) samples of peripheral blood from patients with breast cancer, and no hMAM mRNA was found in peripheral blood of healthy volunteers, but in only one of the 16 patients with breast benign lesions,χ~2=24.173 5, P=0.000. In breast cancer patients, the positive rate of hMAM mRNA was 25.00% (2/8) in stage Ⅰ, 45.80% (11/24) in stage Ⅱ, 43.75%(7/16) in stage Ⅲ, 73.70% (14/19) in stage Ⅳ,respectively. The expression of hMAM mRNA in peripheral blood of breast cancer patients with Ⅳ stage was significantly higher than those in patients with stageⅠ, Ⅱand Ⅲ, χ~2=5.526 8, P=0.018 7. CONCLUSION: hMAM mRNA may be a biological marker of micrometastasis for breast cancer and it can provide important information for estimated prognosis and guiding clinical therapy of breast cancer.