Clinicopathological study on the relationship between serum-CEA and tissue-CEA of resected lung cancer cases

The clinicopathological correlation between serum-CEA (s-CEA) and immunohistological tissue-CEA (t-CEA) was studies on 63 cases of operated lung cancers. T-CEA was examined by peroxidase anti-peroxidase (PAP) method. T-CEAs were detected in 36/39 cases (92.3%) of adenocarcinoma, 16/16 cases (100%) of epidermoid carcinoma, 2/5 cases (40%) of large cell carcinoma, and 1/3 case (33.3%) of small cell carcinoma. T-CEAs in adenocarcinoma and large cell carcinoma with mucin exhibited moderate to strong reactivity with diffuse distribution, and also s-CEA of these cases indicated high levels. On the contrary, in epidermoid carcinoma t-CEAs showed a weak reactivity with focal distribution, and s-CEAs also demonstrated low levels. In adenocarcinoma it was suggested that the more cancers were differentiated, the more t-CEA and s-CEA were increased, and about two third of cases showed a balance between t-CEA and mucin content in cancer tissue. S-CEAs were not correlated with the size of the primary lesion or the extent of lymph node metastasis, but with the histological types, i.e. high levels of s-CEA in adenocarcinoma and large cell carcinoma with mucin.