Angiogenic activity of normal and pathologic human thyroid tissue.

Thyroid tissue was collected from 60 patients during operations for various thyroid conditions. The tissue's angiogenic capacity was assessed in a chick chorioallantoic membrane preparation. Angiogenic activity was observed in 22 (85%) of 26 solitary follicular neoplasms, in none of ten papillary carcinomas and in one of seven glands with Graves' disease (all pretreated with propranolol). Of 17 glands with euthyroid multinodular colloid goitre, three (18%) showed angiogenic activity. No angiogenic activity was detected in normal thyroid tissue from 26 patients. Angiogenic activity of diseased human thyroid does not seem to be a marker of thyroid malignancy.