Medline ® Abstract for Reference 132
of 'Prognostic and predictive factors in early, nonmetastatic breast cancer'
The prognostic value of Ki67 is dependent on estrogen receptor status and histological grade in premenopausal patients with node-negative breast cancer.
Klintman M, Bendahl PO, Grabau D, Lövgren K, Malmström P, FernöM, South Sweden Breast Cancer Group
Mod Pathol. 2010 Feb;23(2):251-9. Epub 2009 Nov 20.
The aim of this study was to evaluate the prognostic value of Ki67 in relation to established prognostic factors in lymph node-negative breast cancer, and furthermore, whether the prognostic impact was dependent on estrogen receptor (ER) status and histological grade. In 200 premenopausal patients, with 5 years of follow-up, Ki67 was determined on tissue microarrays. In univariate analysis, Ki67 (<or = 20 vs>20%) was a prognostic factor for distant disease-free survival (hazard ratio: 2.7, 95% confidence interval: 1.3-5.4, P=0.005) and overall survival (hazard ratio: 4.9, 95% confidence interval: 1.7-14, P=0.003). When stratifying for ER status and histological grade, Ki67 was a significant prognostic factor for distant disease-free survival and overall survival only in the ER-positive group, and only in patients with histological grade 2, respectively. In multivariate analysis, human epidermal growth factor receptor 2 and age were independent prognostic factors for distant disease-free survival, whereas Ki67, histological grade, and tumor size were not. Ki67 was, however, an independent prognostic factor in the 87% of the patients who had not received adjuvant medical treatment. Agreement between the threereaders was very good (kappa-values: 0.83-0.88). Furthermore, Ki67 was a significant prognostic factor for all three investigators (hazard ratio: 2.7-3.2). This study shows that Ki67 is a prognostic factor in node-negative breast cancer. It is noteworthy that the prognostic information of Ki67 is restricted to ER-positive patients, and to patients with histological grade 2. Taken together, Ki67, as an easily assessed and reproducible proliferation factor, may be an alternative or complement to histological grade as a prognostic tool and for selection of adjuvant treatment.
Department of Oncology, Clinical Sciences, Lund University and Lund University Hospital, SE 221 85 Lund, Sweden. Marie.Klintman@med.lu.se