Abstract
During a 5-year period from February 1976, to April 1981, the serum CEA levels of 251 patients, including 233 with lung cancer and 18 with various non-malignant pulmonary diseases were measured at the Department of Radiology, Gunma University, School of Medicine.
The CEA positivity (above 2.5 ng/ml) was 53% in all patients with lung cancer (33% for stage I, 47% for stage II, 44% for stage III and 73% for stage IV) and 22% in the patients with non-malignant pulmonary diseases.The positivity was significantly higher in stage IV. (p<0.01). Lung cancer was considered to be a disease in which serum CEA levels did not become high until an advanced stage. There was no close correlation between serum CEA level and T, N or M factors in patients with lung cancer.
According to the histological type, adenocarcinoma had high serum levels of CEA compared with the other histological types. (p<0.05). On the other hand, oat cell carcinoma did not produce CEA because its serum level was low in spite of advanced stage.
Serial CEA determinations are useful in patients with lung cancer. Patients who responded to radiotherapy showed decreased serum CEA levels when CEA was elevated before therapy. Elevation on further measurements means progressive tumor spread. It is of importance to note that there were some patients who had normal CEA values on the first measurement but had elevated CEA values when metastasis and/or recur-rence appeared after radiotherapy.
