Prognostic significance of expression of c-ERBB-2 oncoprotein in breast cancer patients]

The c-erbB-2 oncogene, is a member of tyrosine kinase oncogene family and expected to play a role in the regulation of cell growth. In the present study, prognostic significance of the expression of c-erbB-2 oncoprotein was investigated by immunocytochemical assay with 130 primary breast cancer patients. The positive expression of c-erbB-2 oncoprotein was found in 53 out of 130 patients (40.8%). There was no significant correlation between expression of c-erbB-2 oncoprotein and conventional prognostic factors, estrogen receptor (ER), axillary lymph node metastasis and epidermal growth factor receptor (EGFR). Relapse free survival rate of the patients with positive c-erbB-2 expression was significantly worse than those with negative at 49 month after operation. Similar result was found in overall survival rate but the difference was not significant. Furthermore, when patients were stratified by regional nodal status, in the patients with lymph node metastasis, the prognosis of the patients with positive c-erbB-2 expression was significantly worse than those with negative, while no significant difference was found in the patients without lymph node metastasis. These results suggest that c-erbB-2 oncoprotein may act as a prognostic factor independently, predicting the prognosis of breast cancer patients.