Thymidine labeling index and Ki-67 staining in breast cancer and their relationship to clinical and pathological variables

Abstract

In this study, two proliferation markers; i.e. thymidine labeling index (TLI) and Ki-67 scores of 32 breast cancer patients were evaluated by assessing the relationship with other prognostic parameters including lymph node status, nuclear-histopathologic grades, tumor size, estrogen-progesterone status and menopausal status. Both TLI values and Kİ67 scores were correlated with nuclear and histologic grades. While indices of both proliferation markers were significantly lower in estrogen receptor positive patients than hormone negative patients, only TLI values were found to be significantly lower in progesterone receptor positive patients. No other correlations or associations between variables reached statistical significance. In conclusion, TLI and Ki-67 scores may be independent prognostic factors as nuclear grade and hormonal status.