Status of Bcl-2 expression and Its Relationship to the Other Prognostic Factors in Breast Cancer / 대한암학회지

ABSTRACT

PURPOSE: There are several well-established prognostic factors to predict the course of breast cancer. Recently, a new category of genes that control the process of programmed cell death, also called apoptosis, has been identified. It includes the bcl-2 proto-oncogene which actively blocks apoptosis. The purpose of this retrospective study is to investigate the relationship between Bcl-2 protein expression in primary breast cancers and other markers of prognostic value. MATERIALS AND METHODS: We analyzed 43 cases of invasive ductal carcinoma of breast cancer, which were consecutively operated in the period from January 1990 to December 1994. Analysis of Bcl-2 protein, ER and PgR expression was carried out using immunohistochemistry on the paraffin-embedded tissue section. The following indices were measured.; size of the tumor, number of axillary metastasis, histological grade, menopausal status, ER, PgR, and Bcl-2 status. RESULTS: Expression of the bcl-2 proto-oncogene was found in 28 cases of 43 patients (65.1%). No relationship could be observed between Bcl-2 status and tumor grade, TNM staging and menopausal status. A strong positive relationship was demonstrated between Bcl-2 immunoreactivity and ER status (P 0.001) and PgR status (P=0.014). A favorable prognostic value was demonstrated for Bcl-2 expression on overall survival (P=0.0427), but no prognostic value was demonstrated on disease-free survival (P=0.1587). CONCLUSION: Our results suggest that the Bcl-2 expression may be a favorable prognostic marker and its important role may be a modulator of response to adjuvant therapy in breast cancer.