Clinical significance of cathepsin D assay in breast cancer tissues

Cathepsin D was assayed in 74 primary breast cancer specimens by enzyme immunoassay (EIA) and immunohistochemical assay (ICA). Of the 74 specimens, 38 (51.4%) were scored positive by ICA, and 25 (33.8%) were scored positive by EIA. The coincidence rate between ICA and EIA was 71.6% (53/74). There was no significant correlation between cathepsin D and menopausal status, tumor size, number size, number of metastatic lymph nodes, histological type of the tumor, or steroid receptor status. Cathepsin D status designated by EIA or ICA predicted neither disease-free survival (DFS) nor overall survival (OAS). Subject analysis with estrogen receptor, menopausal, and lymph node status revealed no association between cathepsin D and DFS or OAS. Therefore, cathepsin D is not an independent prognostic factor in breast cancer.