Detection of circulating breast cancer cells with multiple-marker RT-PCR assay

RT-PCR assay for the multiple markers has been shown to increase the detect ion rate of circulating tumor cells. This assay targeted against cytokertat in 19 (CK19), cytokeratin 20 (CK20) and beta -subunit of human chorioic gon dadotropin (beta -hCG) was used to detect circulating breast cancer cells. 5 ml of peripheral blood was drawn before any surgical procedures from 72 b reast cancer patients and 30 cases with benign breast disease. Total RNA wa s extracted from peripheral blood mononuclear cells, reverse-transcripted a nd amplified. For the benign cases, 10% (3/30) were positive for CK19 and a ll were negative for CK20 and beta -hCG, whereas 9.72% (7/72), 2.78% (2/72) and 12.5% (9/72) ofthe malignant cases were positive for CK19, CK20, but i t increased to 18.1% (13/72) when the marker was combined with beta -hCG. A significant difference was observed for beta -hCG between benign cases and affected patients with stage II, III and IV disease (p= 0.026). In conclus ion, positive RT-PCR signals in blood samples of affected patients correlat ed with stage,in particular for beta -hCG. CK19/beta hCG was a a promising marker combination.