Concentration of thyroxine, tri-iodothyronine and thyroglobulin in the thyroid lymph.

Human thyroid lymphatic fluid was collected from 8 patients operated upon for thyroid tumours. All tumours were of small size and localized to one lobe. The lymph was collected from the side opposite the tumour. The levels of thyroxine and tri-iodothyronine in the lymph were determined by a radioimmunoassay technique in 7 of the patients. The thyroglobulin content of thyroidal lymph from one patient was analysed. The results demonstrate higher levels of thyroxine and tri-iodothyronine in the human thyroid lymphatic fluid as compared with those seen in peripheral or thyroid venous blood. Evidence for the presence of thyroglobulin in the human thyroid lymphatic fluid was obtained.