COMPARATIVE EVALUATION OF ABNORMALITIES OF FUNCTIONAL ACTIVITY OF HYPOTHALAMIC–PITUITARY–THYROID SYSTEM IN PATIENTS WITH BREAST CANCER AND THYROID CANCER
Comparative evaluation of hormone statuses in 178 patients with infiltrating ductal breast carcinoma and 196 patients with papillary thyroid carcinoma in tumor process progression allowed discovering the fact as follows: development of initial and metastatic stages of mentioned cancer forms is formed against the background of totally different changes in functional activity of hypothalamic–pituitary–thyroid system. The tumor growth in patients with breast cancer begins when the level of thyroid-stimulating hormone in blood decreases and the levels of thyroxin and triiodothyronine in blood increase, whereas in patients with thyroid carcinoma at similar stages of tumor process authors noted the enhancement in centrogenous influence on thyroid gland due to thyroid-stimulating hormone hyper-production alongside with the decrease in thyroxin level in peripheral blood with triiodothyronine level being within normal range. 
 Key words: breast cancer, thyroid cancer