Limitations of specific reverse-transcriptase polymerase chain reaction markers in the detection of metastases in the lymph nodes and blood of breast cancer patients

Purpose: This study was performed to evaluate the potential of specific mRNA markers to detect microme-tastases by reverse-transcriptase polymerase chain re-action (RT-PCR) and Southern blot analysis of sentinel lymph nodes (SNs) and blood from patients with breast cancer. Patients and Methods: We assessed the specificity of carcinoembryonic antigen (CEA), cytokeratin-19 (CK-19), CK-20, gastrointestinal tumor-associated antigen-733.2 (GA733.2), and mucin-1 (MUC-1) in the blood of healthy donors (n = 13) and lymph nodes from patients without cancer (n = 3) by RT-PCR assay. The sensitivity of the RT-PCR assay for the target mRNA markers was assessed in breast cancer cell lines (n = 4), primary breast tumors (n = 8), and the frozen sections of SN