Role of thyroid-stimulating immunoglobulin in aggressiveness of well-differentiated thyroid cancer.

ABSTRACT

OBJECTIVE: To assess whether a relationship exists between thyroid-stimulating antibodies and increased aggressiveness of thyroid cancer. METHODS: We analyzed clinical, histologic, and biochemical data, including thyroid-stimulating antibodies, from 26 patients (24 women and 2 men) who had had well-differentiated thyroid carcinoma for 1 to 5 years and had undergone total thyroidectomy and radioactive iodine ablative therapy. For analysis, the overall study cohort was divided into two groups group 1 (N = 16), with stable disease and no evidence of metastatic activity, and group 2 (N = 10), with aggressive disease and substantiated metastatic involvement. RESULTS: The thyroid-stimulating antibodies ranged from 92 to 129% in group 1 and from 95 to 118% in group 2. Thus, both study groups had thyroid-stimulating antibody levels within the normal range (normal, <130%). CONCLUSIONS: Apparently, thyroid-stimulating antibodies had no contributory role in the growth of the metastatic lesions in the 10 patients with aggressive disease. Further studies should be undertaken to investigate other potential factors involved in stimulating the progression of thyroid cancer.