Radioactive iodine is an effective and widely accepted therapy for Graves disease (GD) and differentiated thyroid carcinoma (DTC), but there still are some controversies about the criteria for its use. To establish the present tendency for radioiodine indication, we have sent questionnaires for members of The Brazilian Society of Endocrinology and Latin American Thyroid Society, with 3 index cases: GD, toxic nodular goiter (TNG) and DTC. For each case, questions were proposed about diagnostic procedures and therapy with some clinical variants, which could modify the therapeutic choice. From the almost 2000 questionnaires sent only 82 replies (3.4%) were analyzed. Most of respondents defined themselves as general endocrinologists (85%), working in South and Southeast regions of Brazil (80%), with more than 20 years of professional activity and working mainly at University Hospitals (40%). In case index 1 (GD), 95% of the respondents used arrays of T3, T4 and TSH for the diagnosis and 25% added TRAb and thyroid scan. Antithyroid drugs (ATD) were the first choice for 72%, followed by radioiodine and surgery (26% and 1.3% respectively). None of clinical variants such as severe exophtalmos, older age or goiter size modified the therapy. In case 2 (TNG), radioiodine was the first therapy for 84% of professionals and the presence of compressive symptoms was the only variant that changed this tendency, when surgery was the main option. In case 3 (DTC), almost all indicated total thyroidectomy. Radioiodine for thyroid remnants was proposed by 45% of respondents, independent of residual uptake, while the remaining did so depending of different values of uptake, giving 30 to 100mCI. These data show that radioiodine use is increasing for hyperthyroidism, but still less than observed in other countries and that we do not have uniformity for treatment of DTC.
Radioactive iodine; Graves' disease; Differentiated thyroid carcinoma; Toxic nodular goiter
