Carcinomas with apocrine differentiation: Comparison of clinicopathologic features with invasive breast carcinoma of no special type (NST) in Turkish patients

When a total of 2488 Turkish patients were taken into consideration, carcinomas with apocrine differentiation accounted for 0.7% of invasive breast carcinomas. The aim of this study was to evaluate clinicopathologic features of this rare type breast carcinoma in Turkish population. To our knowledge, our study has a unique specialty as having broadest group of Turkish patients with apocrine carcinoma, so far. Parameters such as patient's age, tumor size, nodal metastasis, lymphatic - vascular invasion, immunohistochemical expressions of estrogen receptor, progesterone receptor, HER2 status were documented and compared with invasive ductal carcinoma of no special type. Against 20 cases of apocrine carcinoma, a grade-matched control group of 40 invasive ductal carcinoma was formed. Prognostic features such as overall survival period and relapse - free survival period were also studied; but only for a limited follow - up period with an average of approximately 30 months. Usual negativity of estrogen and progesterone receptors in apocrine carcinoma was once more confirmed by this study. Results were consistent with related literature, indicating presence of poor significant difference between clinicopathologic features of apocrine carcinoma and the other invasive ductal carcinomas of breast.