Assessment of prognostic value FOXA1 Expression in breast carcinoma after neoadjuvant chemotherapy: Immunohistochemically Study

: Background: Breast carcinoma is the most common malignant tumor and the leading cause of carcinoma death in women. Aim and objectives: to determine the expression of FOXA1 in breast carcinoma, to correlate the expression of FOXA1 with hormonal receptors (ER and PR), Her2\neu, Ki67and pathological response to chemotherapy. Patient and method: This retrospective study was carried on 100 controlled, selected cases included seven cases with bilateral breast cancer, eighty-six cases IDC, five cases ILC, ductal carcinoma insitu (DCIS) was three cases, medullary carcinoma three case, two cases papillary and one case tubular. Fifty-six cases of the total cases with positive axillary lymph nodes metastasis. It was performed on formalin-fixed paraffin-embedded tissue blocks of specimens, collected from Pathology Department, Faculty of Medicine, Benha University, from the years (2013-2019). Result: Concerning the pathological response was found that, FOXA1 was positive in forty-four (44) out of fifty (50) cases with complete pathological response, twenty-seven (27) out of thirty-seven (37) cases with partial pathological response and seven (7) cases out of thirteen (13) cases with no pathological response. While for (ER), (89) cases are positive out of them (74) case FOXA1 positive, and (PR), (80) cases positive, FOXA1 positivity (68) out of them, however Her-2\neu negative cases were (48) from them (41) case are FOXA1 positive. For Ki-67, fourteen (14) cases show low scoring, while (31) cases has intermediate score and (55) cases has high scoring, FOXA1 positivity out of them (14, 31, 33 cases respectively). Conclusion: FOXA1 is a marker of good prognosis in breast cancer as FOXA1 expression associated with complete pathological response, positive hormone receptors and low-intermediate Ki67.