Circulating thyroglobulin and antithyroglobulin antibodies after fine needle aspiration of thyroid nodules.

Circulating thyroglobulin and antithyroglobulin antibodies were assayed in fifteen patients affected by solitary "cold" nodules of the thyroid who had undergone fine needle aspiration for cytologic diagnosis. The aim of the study was to investigate whether a minor insult to thyroid tissue such as fine needle aspiration is able to release thyroglobulin into the circulation and to induce the formation of antithyroglobulin antibodies. The results obtained are as follows: 1. Circulating thyroglobulin increased substantially after fine needle aspiration in 11 out of 15 patients. 2. Antithyroglobulin antibodies did not appear in any patient during a follow-up period of two months. 3. The magnitude of basal thyroglobulin and thyroglobulin increase after needle aspiration were unrelated to cytologic diagnosis.