CEA positivity in sera and breast tumor tissues obtained from the same patients.

It is well known that the concentration of serum CEA correlates best with colorectal carcinomas but less well with other solid tumors. The aim of the present study was to elucidate further the poor relationship between confirmed primary mammary carcinomas and CEA serum levels, 108 of these tumors have hence been studied for their tissular CEA positivity and the results obtained were compared with the CEA serum values found preoperatively in the same patients. Techniques employed were the indirect immunoperoxydase method for the histologic studies and the enzymoimmuno-assay for the serum measurements. The discordance and concordance of the CEA results obtained with the two techniques were analyzed in respect to the histologic types of tumors classified following the ICD-O nomenclature. Our results seem to prove that: 1) although most tumors produce the antigen only a fraction of them releases it, and 2) the most common histologic type of tumor is the one secreting the antigen the less frequently. These observations are apparently independant of the tumor stages T1-T4, N- or N+, M-.