RT-PCR detection of breast cancer cells in sentinel lymph modes

Sentinel lymph node (SLN) biopsy is being evaluated in breast cancer patien ts to improve detection of metastases and to guide therapy with minimal mor bidity. The aim of this study was to increase the sensitivity of tumor cell detection in SLNs using superior reverse transcription polymerase chain re action (RT-PCR) for carcinoembryonic antigen (CEA) and mammaglobin (MMG) an alysis rather than current methods which fail to identify clinically releva nt disease in many patients. In seventy stage I and II breast cancer patien ts dye-guided lymph node mapping was performed and the SLNs were divided al ternately for RT-PCR or hematoxylin and eosin staining (H&E), RT-PCR and H& E diagnosis of SLNs were compared. SLNs were identified in 66/70 (94.3%) pa tients. Seventeen patients (26.2%) had histological metastasis in SLNs. CEA was expressed in 25.0% of 48 patients with H&E negative SLNs, acid MMG was expressed in 20.8%. SLNs could predict axillary lymph node status with 95. 4% accuracy and 6.3% false negative rate by H&E. Moreover, RT-PCR improved these to 98.5% and 2.8%, respectively. SLN diagnosis using RT-PCR is a powe rful and sensitive method, which increases the accuracy of clinical staging and may provide more informed choices for appropriate therapeutic manageme nt of breast cancer patients.