Immunohistochemical cathepsin-D expression in breast cancer: Correlation with established pathological parameters and survival

Breast cancer is an increasingly important cause of illness and death among women. In recent years, several novel prognostic determinants of breast ca ncer have been identified, including Cathepsin-D (CD) protein. CD protein e xpression was analyzed immunohistochemically (IHC) in tumor specimens (315 patients) of infiltrating ductal breast carcinoma. These patients also had axillary lymph node sampling. Overexpression of CD was observed in 39% of t he tumors. IHC results were compared with the histological grade. Seventy n ine percent (n = 95; 79%) tumor positivity was seen in grade II tumors, fol lowed by grade I (n = 13; 11%) and grade III tumors (n = 12; 10%). Axillary lymph node metastasis had no significant correlation with CD positivity (p < 0.05). Bone metastases were significantly correlated with CD positivity (p < 0.05). CD positivity showed no significant correlation with disease-fr ee and overall survival (p > 0.05). At a median follow-up of 48 (4 years) m onths in CD-positive patients, overall survival was 3.17 years, and disease -free survival 2.67 years. The overall survival of CD-negative tumor patien ts was 3.50 years, and disease-free survival was 2.93 years. We conclude th at in comparison with cytosol-based quantitative studies, CD expression is not a good prognostic marker when, as in all ICH studies, only the expressi on in the tumor is considered.