[Cathepsin D: an independent prognostic factor in cancer of the breast]

The total amount of cathepsin-D (mature forms and pro-enzyme especially) in the cytosol of 88 breast cancers including 85 primary cancers and 11 axillary lymph node metastasis was measured by way of immuno-radiometric assay. Maximum follow-up is 58 months. Cathepsin-D was found to be independent of clinical and biological parameters including axillary lymph node involvement and oestradiol receptors (RE). Univariate analysis has pointed out a significant linkage between overall survival and cathepsin-D, using a cut-off level of 30 pmol/mg protein which is the most discriminating value. Cathepsin-D appeared to be particularly useful in lymph-node-positive and RE-negative patients but it was not significant in the node-negative population. Multivariate analysis of the overall survival (Cox model) revealed that it was strongly related to oestradiol receptor, lymph node involvement and cathepsin-D.