Tissue Factor Expression in Triple-Negative Breast Carcinomas
XM Zhang, CM Schneider, A Padmanabhan, R Sterling, ME Bromberg. Temple University, Philadelphia, PA
Background: Tissue factor (TF) is expressed in a variety of tumor cells and has been linked to cellular signaling, angiogenesis, and tumor progression. However, its role in human cancer is not fully known. Recently, upregulation of TF has been linked to expression of epidermal growth factor receptor (EGFR), a prognostic factor of breast cancer. Triple-negative (ER, PR and HER-2) breast carcinomas (TNBC) belong to a subgroup of breast cancer with aggressive clinical behavior and poor prognosis.
Design: Forty-five cases of TNBC diagnosed from 2003 to 2008 were retrieved from the archive of the Department of Pathology of Temple University. Adequate tissue was available in 41 cases that formed the basis of this study. All patients were female with an age range from 32 to 81. Immunohistochemistry for CK5/6, EGFR and TF was performed, and results were scored as positive (tumor cells stained) or negative (no tumor cell stained). Basal-like carcinoma (BLC) was defined as a TNBC positive for CK5/6 and/or EGFR.
Results: 20 (49%) of patients presented with regional lymph node metastasis, 9 (22%) demonstrated distal metastasis and 24 (59%) had advanced clinical stage (III/IV). All cases were invasive ductal carcinoma (IDC), except for one adenoid cystic carcinoma. 36 of the 40 IDC were histologically high grade and the remaining 4 were intermediate grade. BLC was identified in 36 of the 41 (88%) cases, among which 21 (58%) were positive for both CK5/6 and EGFR, 14 (39%) were positive for only CK5/6 and 1 (3%) was positive only for EGFR. The remaining 5 cases were negative for both markers (non basal-like carcinoma, NBLC). Overall, TF expression was found in 35 of the 41 (85%) cases. TF expression was detected in 31 of 36 (86%) BLC and in 4 of 5 (80%) NBLC. With respect to EGFR expression, 18 of the 22 (81%) cases positive for EGFR expressed TF, however TF expression was also found in 4 of 6 (80%) cases that lacked EGFR expression.
Conclusions: TF expression was found in the majority of cases of TNBC (88%), suggestive that TF expression is linked with the aggressive tumor behavior and poor prognosis of the patients with TNBC. Tumor TF expression was similar in BC (86%) and NBC (80%). However, a close association between TF and EGFR expression was not observed. Further study is warranted to explore the clinical significance of TF expression and its association with EGFR expression in this breast cancer subtype.
Tuesday, March 23, 2010 9:30 AM
Poster Session III # 50, Tuesday Morning