Investigation of the relationship between FHIT expression and response and prognosis to neoadjuvant chemotherapy in triple negative breast cancer patients

Breast cancer is the most common type of cancer in women worldwide and has the highest mortality rate. The most aggressive type of cancer is triple negative breast cancer (TNBC), which is a poorly prognostic subtype of breast cancer. Estrogen, progesterone, and HER2 receptor expression are absent and an option of targeted therapy is not available. Therefore, currently it can only be treated with chemotherapy. With the neoadjuvant treatment, it is aimed to reduce the risk of recurrence, to increase the chance of surgical intervention, to reduce the risk of complications after surgery and to increase the quality of life. TNBC is one of the subgroups with the best tumoral, nodular and pathological response to neoadjuvant chemotherapy. In this study, it was aimed to show the relationship both between the response to neoadjuvant chemotherapy and Fhit expression and between Fhit expression and clinical pathological data in TNBC patients. FHIT is a tumor suppressor gene located in the fragile region of FRA3B. Loss of Fhit expression is frequently seen in breast cancer. 50 patients with TNBC were included in the study. Fhit expression in formalin-fixed parafine-embedded (FFPE) blocks was evaluated immunohistochemically (IHC). Fhit expression percentages and scores were in comparison with clinical pathological and survival data. T-stage was found to increase in patients with loss of Fhit expression and it was statistically significant (p=0.003). In our study, the relationship between Fhit expression in TNBC and clinical pathological and prognostic factors, other than T stage, could not be significantly demonstrated (p>0.05). However, loss of Fhit expression may be a negative prognostic marker for overall survival. Larger-scale studies are needed to elucidate the relationship between Fhit expression loss and TNBC. The results we obtained from our study are compatible with the literature and will contribute to the field with new data and shed light on future research on this subject.