Cathepsin D: association between TN-stage and steroid receptor status of breast carcinoma.

PURPOSE

To assess whether the expression of estrogen-induced protease, cathepsin D, might facilitate biological subgrouping of patients with breast carcinomas, and accordingly, its potential applicability in clinical oncology.

PATIENTS AND METHODS

This study includes 70 patients with histologically confirmed breast carcinoma. Pathological findings were classified according to tumor size (T) and the presence or absence of metastases in regional lymph nodes (N). Steroid hormone receptor (SR) density as well as cathepsin D concentrations were assayed in the cytosol of breast carcinomas in accordance with the recommendation of the EORTC.

RESULTS AND DISCUSSION

Statistically significant direct correlations were observed between cathepsin D expression and axillary node status as well as SR status. However, it is important to point out that in spite of these statistically significant findings, there were no biologically significant associations due to a wide range of individual cathepsin D values. Baseline levels of cathepsin D expression were found in patients with SR-negative status and node-negative tumors as well as in patients with SR-negative status and tumors of </=2 cm. Accordingly, a clinical significance of cathepsin D expression may be assumed.