Detection of occult tumour cells in lymph nodes of colorectal cancer patients using real-time quantitative RT-PCR for CEA and CK20 mRNAS
The purpose of our study was to develop specific, sensitive, objective assays for early detection of disseminated tumour cells in patients with colorectal cancer (CRC). Carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20) were chosen as markers because they are selectively expressed in epithelial cells with maintained expression in CRC. Real-time quantitative RT-PCR assays with RNA copy standa