Thymidine labeling index in breast cancer prognosis

Abstract

In addition to primary prognostic factors (tumor size, axillary lymph node status, histological and nuclear grade, estrogen receptor status, etc.), cell kinetics may help to predict outcome and determine treatment for breast cancer. Thymidine labeling index (TLI), which is a kinetic parameter showing tumor aggressivity and cell proliferation rate, is shown among the secondary group of prognostic factors. At Istanbul University, Istanbul Faculty of Medicine, Breast Diseases Research and Treatment Unit, TLI was determined in tumor tissues of 154 patients with primary breast cancer. TLI values varied in the range of 0%-23.59% with a mean of 4.31% ± 0.36% and a median of 3.10%. TLI levels were compared with age, menopause status, axillary involvement, tumor diameter, histological and nuclear grade, estrogen receptor level, and tumor histology. There was no statistically significant correlation between TLI and prognostic factors (p > 0.05). One hundred and eleven patients were followed up for an average of 14.0 months. Twenty-nine patients (26.1%) relapsed and there were 11 (10%) deaths. On the one hand, the low TLI group ( 3%). Nevertheless, these results were not statistically significant (p < 0.05). Thus, TLI appears to be independent of the known prognostic factors for breast carcinoma. According to preliminary results, high TLI levels seem to be associated with higher mortality rates.