Cathepsin B, a prognostic indicator in lymph node-negative breast carcinoma patients: Comparison with cathepsin D, cathepsin L, and other clinical indicators

New prognosticators are needed for breast cancer patients after the initial surgical treatment to make therapeutic decisions that ultimately will. aff ect their DFS, These consist of specific proteolytic enzymes including lyso somal endopeptidases, In this study, the activity and protein concentration s of cathepsins (Cats) D, B, and I, were measured in 282 invasive breast tu mor cytosols. These potential biological prognostic indicators were compare d with other histopathological parameters, such as tumor size, lymph node i nvolvement, tumor-node-metastasis stage, histological grade, DNA analysis, and steroid receptors, CatD protein concentration correlated with lymph nod e involvement. CatB and CatL levels correlated significantly with Scarf-Blo om-Richardson histological grade and were also higher in estrogen-negative tumors, and CatB was;as higher in larger tumors. As prognostic markers, CatB concentration was significant for increased ris k for recurrence in the entire patient population and specifically also in lymph node-negative patients as follows: high CatB concentration (above 371 mu g/g) in tumor cytosols was significant (P < 0.00) for high risk of recu rrence but was of only borderline prognostic significance (P < 0.06) for ov erall survival of all patients. In lymph node-negative patients, CatB (abov e 240 mu g/g, P < 0.003) was highly significant for recurrence-free surviva l, followed by CatL (above 20 mu g/g, P < 0.049) and CatD (above 45 nmol/g, P < 0.044) concentrations. For overall survival of node-negative patients, only CatB was a significant (P < 0.014) prognosticator, We conclude that C atB is useful as a prognostic indicator in lymph node-negative patients. Th is suggests that selective adjuvant therapy should be applied in this lower risk group of patients when high levels of CatB are determined.