CEACAM5 and breast cancer: To our best knowledge, the present study is the fourth one in the last 40 years (Pub-Med search) providing information regarding the neoplastic tissue Se concentration in breast cancer patients and the first one providing data for serum/tissue Se concentrations simultaneously, in association with serum CEA levels (Garg et al, 1994; Sharma et al, 1994; Kuo et al, 2002).