Expression of Cox-2 and Bcl-2 in Paget's disease of the breast

Paget's disease (PD) is a rare form of intraepithelial adenocarcinoma that involves breast and extramammarian tissues. It is often associated with ductal carcinoma in situ and/or invasive ductal cancer. Molecular pathways that play a role in development of Paget's disease are stil unclear. Expression patterns of Cox-2 and bcl-2 were therefore assessed.

Patients with a histopathological diagnosis of Paget's disease were included in this study. Patient files were analysed retrospectively.

Invasive cancer was diagnosed in 35 (76.1%) of the patients, 7 (15.2%) had ductal carcinoma in situ and 4 (8.7%) patients had no associated neoplasm. Twenty four (52.2%) patients showed COX-2 expression in Paget cells whereas no expression was seen in 22 (47.8%) patients. No relation was found between COX-2 expression and the lesion underlying Paget's disease (p=0.518). Bcl-2 expression in Paget cells was found positive in 12 (26.1%) and negative in 27 (58,7%) cases. There was no relation between Bcl-2 expression and the lesion accompanying Paget's disease (p=0.412). No relation was observed between COX-2 expression and Bcl-2 expression (p=0.389).

In breast cancer, COX-2 expression is associated with poor prognostic factors. As COX-2 expression increases the tendency to metastasize also increases. In our study we found a significantly high COX-2 expression in Paget's disease of the breast. We suggest that COX-2 expression and inflammatory processes may play a role in pathogenesis of the Paget's disease of the breast.