Different Prognostic Factors Correlate with Bcl-2 Expressionamong Triple Negative and Non-Triple Negative Breast Cancers

Abstract

Background: Prognostication of breast cancer using clinico-pathologic variables, although useful, remainsimperfect. Recent research has focused on finding new markers of prognosis using gene expression profiling.Panels of proteins assessed by immunohistochemistry might also be useful in this regard. This study focusedon Bcl-2 protein expression in triple-negative (TNBC) and non- triple-negative breast cancer (non-TNBC) withcorrelation to clinico-pathologic variables. Materials and methods: We analyzed Bcl-2 expression in 77 womenwith primary breast carcinoma divided into two groups; triple-negative and non- triple-negative according toexpression of estrogen (ER), progesterone (PR) and human epidermal growth factor receptors (Her2/neu). Bcl-2expression was assessed in relation to age, histo-pathological subtype, grade, nodal status and tumor size.
Results:Bcl-2 was expressed in 74% of triple-negative breast cancers and 70% of non- triple-negative cancers. In TNBC,expression was significantly correlated with invasive ductal subtype, while in non-TNBC it was significantlycorrelated with age and negative nodal status. In both groups higher Bcl-2 expression associated with favourableprognostic factors in breast cancer, but no significant statistical correlations were found.
Conclusions: Frequencyof Bcl-2 expression does not differ between TNBC and non-TNBC, but different prognostic factors correlatewith Bcl-2 in the two cases.

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