Carcinoembryonic antigen in thyroid disease.

Plasma carcinoembryonic antigen (CEA) levels were measured by the Z-Gel technique in 138 patients with benign thyroidopathies, 25 patients with thyroid cancer, and 141 normal persons. Levels were raised (above 5 ng/ml) in 2% of the normal subjects, in none of the patients with benign thyroidopathies, and in 20% of the patients with thyroid cancer. They were considerably raised in all cases of medullary carcinoma of the thyroid but they were also high in other histological types of thyroid cancer. Measurement of plasma CEA may be of value in the preoperative diagnosis and follow-up of patients with thyroid cancer.