EVALUATIN OF ErbB-2 PROTEIN IN TISSUE EXTRACT COMPARED WITH OTHER PROGNOSTIC FACTORS IN HUMAN BREAST CANCERS

ErbB-2 protein levels in breast cancer extracts in 128 patients were mesured by EIA, and compared with other well-known prognostic factors. In primary breast cancer, 12.3% (15/122) of the cases were found to be positive for ErbB-2 protein, and 33.3% (2/6) of the non-primary cases were positive for ErbB-2 protein (the cut-off value of ErbB-2 protein was set at 18.0ng/mg prot) Overexpression of ErbB-2 protein was significantly associated with lymphatic vessel invasion (p=0.0158) and negative estrogen receptor (p=0.0127). It also related to large tumor size, but there was no significant difference. However, overespression of ErbB-2 was not associated with age and lymph node metastases. These results suggest that the commbined use of classical prognostic factors and mesurement of ErbB-2 protein may improve prognostic value and contribute to adjuvant chemotherapy and hormonal therapy.