Low T3 syndrome with hyperthyrotropinemia and early detection of liver metastasis.

Abstract

e23010 Background: Numerous clinical studies have shown an association between changing thyroid gland (TG) function and the development of tumors. The purpose of the study was to analyze the dynamics of thyroid hormones in the pituitary gland, TG and blood serum (BS) during liver metastasis in order to create thyroid profile of metastasis and to detect thyroid markers of metastasis in BS. Methods: The experiment included 44 white male rats weighing 180-250 g. Sarcoma 45 was transplanted intrasplenically. Levels of thyroid stimulating hormone (TSH) were studied in the pituitary gland, TG, BS; the amount of free (fT4) and total (T4) thyroxine and free (fT3) and total (T3) triiodothyronine in TG and BS were determined by radioimmunoassay (Immunotech, Czech Republic; Arian analyzer, Russia). Results: Exertion of the pituitary gland and overproduction of TSH were observed since the early days of the tumor development, later accompanied by TG hypofunction. Quantitative changes of thyroid hormones in organs did not coincide with their dynamics in BS. The first diagnostic signs of experimental liver metastasis, in the absence of formed metastases in the body, were hyperthyrotropinemia and a tendency to fT3 decrease in BS. Already formed liver metastases were characterized by a marked low T3 syndrome which transformed into a more severe lowT3/lowT4 syndrome during the secondary metastasis. Conclusions: The development of liver metastases is accompanied by the exertion and imbalance of the thyroid system function. Analysis of dynamics of the thyroid axis hormones in BS allows predicting the appearance of liver metastasis and identification of “the point of no return” in the development of the pathology that leads to secondary metastasis and irreversible progression of the disease.