RESUMEN
The study of different epithelial antigen expression has been performed in 183 breast cancers. In 73 patients regional lymph nodes were studied as well. Panepithelial antigen Egp-34 (Mab HEA-125) was expressed in 100% of primary tumors and metastases. Antigen MUC-1 (Mab ICO-25) was identified in 93% of breast cancers. Monomorphic type of expression in tumor cells was typical for Egp-34, MUC-1 being in certain cases expressed as a proportion of cells. Additional immunohistochemical study of regional lymph nodes with Mab to Egp34 and MUC-1 provides a 10% increase in the rate of breast cancer metastases detection compared to histological examination alone. The carcinoembryonic antigen (CEA) was useful in identification of metastases only in CEA-positive breast cancers.