The aim of our study was to assess the effectiveness of radioiodine therapy (RIT) on the achievement of euthyroidism and reduction of thyroid volume, in patients with toxic nodular goitre (TNG).
Material and methods: During the last 7 years, we treated 3800 patients with TNG, aged 30-70 years; 82% female and 18% male; 2200 patients with multinodular goitre (MNG) and 1600 with autonomous toxic nodule (ATN); thyroid volume ranged between 16 and 130 ml (30% with thyroid volume >60 ml).
Qualification of these patients were based on clinical features, characteristic appearance on thyroid scans and ultrasound. Malignant changes were excluded in all nodules by fine needle aspiration biopsy. All the patients had serum TSH levels below 0.1 mU/l and effective half-life more than 3 days at the time of treatment. The activity dose was calculated by Marinellis formula and ranged between 200 and 800 MBq. The absorbed dose (Gy) ranged between 150 and 260 for MNG, and 200-300 for ATN. Follow-up control was done every 6 weeks. Thyroid ultrasound, and thyroid scan were done before and after12 months of RIT to assess RAIU, volume of thyroid gland and nodules. Repeated RIT was given after 6 months of the first dose if needed.
Results: After 4 years of follow-up, the success of treatment was: 97% of patients with ATN and 92% of patients with MNG achieved euthyroidism. Three percent of patient with ATN and 8% of patient with MNG develop hypothyroidism. Thirty-four patients with toxic MNG and 5 patients with ATN received more than one dose of RIT. Thyroid volume reduced to 52% in MNG and 47% in ATN.
Conclusions: The achievement of euthyroidism and the remission of the symptoms and signs of clinical hyperthyroidism, were due to well preparation of the patients; accurate measurement of administered activity, relatively high effective half-life, and well-organised follow-up.
03 - 07 May 2008
European Society of Endocrinology