Significance of immunohistochemical c-ErbB-2 product localisation pattern for prognosis in human breast cancer.

Breast cancer is an increasingly important cause of illness and death among women. In recent years several novel prognostic determinants of breast cancer have been identified, including c-ErbB-2. In this study, expression of c-ErbB-2 in breast carcinoma was correlated with axillary lymph node metastases and disease outcome. The expression of c-ErbB-2 oncoprotein was analysed in 315 tumor specimens of infiltrating ductal carcinoma of breast. They were categorized according to the modified Bloom and Richardson criteria into three histological grades. These patients also had axillary lymph nodes sampling. The expression of c-ErbB-2 oncoprotein was analysed immunohistochemically. Over expression of c-ErbB-2 were observed in 39.36% tumors. Axillary lymph node metastasis had significant correlation with intensified positivity of c-ErbB-2. C-ErbB-2 positive patients did show resistance to chemotherapy when compared for recurrence and distant metastases following surgery (p< 0.05). At a median follow-up of 48 months in c-ErbB-2 positive patients, the overall survival was 3.0 years and disease free survival was 2.5 years. c-ErbB-2 negative tumor patients showed a far better survival. In this group the overall survival was 4.44 years and the disease free survival was 3.78 years. These findings reinforce the view that c-ErbB-2 immunohistochemical detection is of help in detecting a subgroup of breast carcinoma patients who are at high risk. This may also be of particular relevance in decisions regarding adjuvant chemotherapy to these patients.