The Relationship of GATA3 and Ki-67 With Histopathological Prognostic Parameters, Locoregional Recurrence and Disease-free Survival in Invasive Ductal Carcinoma of the Breast

Background: In recent years, GATA-binding protein 3 (GATA3) has been indicated as a marker showing good prognosis in breast cancer. In luminal breast cancer, which has good a prognosis, it shows more significant elevation in small-sized and low-grade tumors. In contrast, Ki-67 is defined as a poor prognostic factor. The aim of this study was to emphasise the prognostic importance of GATA3 and the inverse relationship with Ki-67. Materials and Methods: In our study, 90 patients with invasive ductal breast cancer were immunohistochemically evaluated for Ki-67 and GATA3 expression. The relationship between GATA3 and Ki-67 expression was examined. In addition, the relationship between these two factors with estrogen, progesterone, human epidermal growth factor 2 receptor antibodies and other prognostic parameters such as disease-free survival and local recurrence was investigated. We accepted the level of >= 5% nuclear reaction as positive for GATA 3. A Ki-67 cut-off value of 20% was accepted as positive. Results: In GATA3 positive breast cancers, good prognostic parameters were seen including high estrogen receptor (ER) positivity, progesterone receptor (PR) positivity, small tumor size and low histological grade as well as low Ki-67 expression. In breast cancers showing high Ki-67 expression, ER, PR, and GATA3 positivity were lower and there was higher human epidermal growth factor receptor 2 (HER2) positivity and high histological grade while the tumor size was larger. Conclusion: Our study has revealed that GATA3 has an inverse relationship with Ki-67, whereas it has a positive releationship with good prognostic factors.