An immunohistochemical determination of the growth fraction (gf) with the ki-67 monoclonal antibody has been performed in a prospective series of 140 patients with primary operable breast carcinoma. Gf ranged from 0% to 43% ki-67 stained cells with a median value of 8%. High gf (> 8%) was significantly associated with axillary node involvement (p = 0.006), aneuploidy (p = 0.008), histologic grade (p = 0.03), and s-phase fraction > 5% determined by flow cytometry (p = 0.01). After a median follow-up of 6 years, the univariate analysis did not show significant correlation between high gf and worse relapse-free survival (p = 0.10) or shorter overall survival. However, a multivariate analysis on relapse-free survival, performed in 127 comparable patients, showed that gf was an independent predictive factor (p = 0.03) together with nodal status (p = 0.00001), age under 45 years (p = 0.0008), and chemotherapy (0.006). In node negative patients, gf was still an independent prognostic indicator (p = 0.002) together with age under 45 years (p = 0.0003). Tumor proliferative activity evaluated by the monoclonal antibody ki-67 appears to be an effective indicator of prognosis in breast cancer and could be of assistance in the decision making of adjuvant therapy in node negative patients.
Hillen, H. F. P., Blijham, G. H., von Meyenfeldt, M. F., Volovics, L., Schutte, B., Schouten, L. J., Jager, J. J., de Jong, J., Schouten, H. C., & Hupperets, P. S. G. J. (1996). Prognostic factors in node-negative breast cancer patients: 7 years follow-up. Breast Cancer Research and Treatment, 37(S), 57. https://doi.org/10.1007/BF01806632