An immunohistochemical study in thyroid cancer.

Follicular, papillary, anaplastic and medullary cancers of the thyroid were investigated using immunohistochemical methods. The following antibodies were used: anti-S-100, antineuron-specific enolase (NSE), antikeratin, antithyroglobulin, anticalcitonin, anticarcinoembryonic antigen (CEA), antiepithelial membrane antigen (EMA); the following hormones were also tested in the medullary carcinoma: gastrin, ACTH and serotonin. Papillary and follicular carcinoma in particular reacted with anti-S-100 and anti-NSE; the anaplastic neoplasia reacted with anti-S-100 (25%), anti-NSE (12%), antikeratin (12%), antithyroglobulin (12%), anti-CEA (37%) and anti-EMA (37%). Medullary carcinoma reacted with anticalcitonin (100%), anti-CEA (96%), anti-NSE (79%), anti-EMA (4%) and anti-S-100 (17%). We were not able to correlate the virulence of the medullary carcinoma with the anticalcitonin and anti-CEA reactivity, while the hyperplastic C cells were immunoreactive both with calcitonin or with CEA.