Expression of Cyclin D1 and bcl-2 in Infiltrative Ductal Carcinoma of the Breast: Their Correlations and Clinical implications

Abstract

This study was designed to analyze the correlations of cyclin D1 and bcl-2 and their clinical implications in breast cancer. Methods: Immunohistochemical expression of cyclin D1 and bcl-2 were studied in 342 infiltrative ductal carcinoma cases and were compared with clinicopathologic parameters such as age, tumor size, histologic grade, lymph node status, p53, c-erbB2 and hormone receptors. Results: Cyclin D1 expression was found in 86 of 342 cases (25.1%). Bcl-2 was positive in 227 of 342 cases (66.4%). Bcl-2 overexpression was associated with the high expression of cyclin D1 (p=0.001). Correlation was detected between both cyclin D1 and bcl-2 and hormone receptor positivity (p<0.001). There was a reverse correlation between bcl-2 and histologic grade, p53, c-erbB2. And the bcl-2 overexpression group showed better disease free survival rates at 3-year follow up. Conclusion: Higher expression of cyclin D1 was associated with bcl-2 overexpression. Positive estrogen receptor expression was associated with high cyclin D1 and bcl-2 expression. Bcl-2 tends to correlate with a positive clinical outcome.