Immunohistochemical Evaluation of TFF1 and TFF3 Expression in ER-Negative Breast Carcinomas
Haiyan Liu, Jianhui Shi, Jeffrey Prichard, Fan Lin. Geisinger Medical Center, Danville, PA
Background: The human trefoil proteins TFF1 and TFF3 belong to the trefoil factor family, expressed primary in the epithelial cells of gastrointestinal tract. TFF1, also called PS2, is frequently expressed in breast carcinomas (BCA) under the control of estrogen. Studies reveal that TFF1 expression is associated with BCA with ER-positive status and better prognosis. Our previous studies on tissue microarray (TMA) BCA, including invasive ductal carcinomas (IDC, G1, 2, 3 and other special types) and invasive lobular carcinomas (ILC, G1,2 and 3), demonstrated that 72% of IDC and 87% of ILC are reactive to TFF1; 84% of IDC and 94% of ILC, to TFF3. The ER-positive rates in TMA BCA are 74% for IDC and 84% for ILC. In contrast, the vast majority of lung adenocarcinomas, endometrial adenocarcinomas and ovarian serous carcinomas were negative for TFF1. In the current study, we immunohistologically evaluated the expression of TFF1 and TFF3 in 49 consecutive ER-negative BCA on core needle biopsy specimens using a single immunostaining system (Ventana).
Design: Immunohistochemical evaluation of the expression of TFF1 (Epitomics, AC-0045RUO) and TFF3 (Epitomics, AC-0103RUO) was performed on 49 consecutive ER-negative BCA, including mainly IDC, G2, G3 and a few other special types, such as metaplastic and medullary carcinomas on core needle biopsy specimens, using a Ventana immunostaining system. The staining intensity was graded as weak or strong. The distribution was recorded as negative (<5% of tumor cells stained), 1+ (5-25%), 2+ (26-50%), 3+ (51-75%), or 4+ (>75%).
Results: Fourty-five percent (22/49) of ER negative BCA showed focal or diffuse positivity for TFF1. Eighty-six percent (42/49) of the ER-negative BCA were nonreactive to TFF3. Staining patterns of the positive cases were summarized in table 1.