Estrogen-dependence of thyroid carcinoma: testing with estradiol preparations and tamoxifen
Bershteĭn, L.M.; Tsyrlina, E.V.; Porozova, A.A.; Poroshina, T.E.
Voprosy Onkologii 54(6): 710-714
2008
ISSN/ISBN: 0507-3758 PMID: 19241844 Document Number: 615517
Twenty-four patients with thyroid carcinoma receiving thyroxine were examined. The thyroid gland had been extirpated in 20; hemithyreoidectomy (4). Tests with ethinyl estradiol (50 mcg, per os, 6 days) (8), estradiol valerate (2 mg, per os, 12 days) (10), and tamoxifen (40 mg, per os, 14 days) (6) were carried out on the assumption of normal and neoplastic thyroid epithelium sensitivity to estrogen stimulation. Blood thyroglobulin, TSH and estradiol levels were assayed before and after loading. Thyroglobulin concentrations increased in 5 out of 24 patients (ethinyl estradiol--1 out of 8, estradiol valerate--2 out of 10 and tamoxifen--2 out of 6); those of TSH--in 6 out 24 (3 out of 8, 2 out of 10 and 1 out of 6, respectively). Enhanced thyroglobulin correlated with higher levels of TSH in 2 out of 5 and with blood-estradiol--in 4 out of 5. It was suggested that at least, in some patients, the preparations might produce a direct stimulating effect on thyroglobulin biosynthesis in the thyroid tissue remnants. Further research is suggested or on whether tamoxifen exerts pro- or antiestrogenic influence on thyroid epithelium.