Endocrine Abstracts

Most of the patients with the benign cold nodule refuse surgical operation. Radioiodine therapy (RIT) is the choice for these patients. The aim of our study was to evaluate the efficacy of radioiodine therapy to reduce thyroid volume in patients with cold nodule by the use of two doses of radioiodine.

Methods: We treated 40 patients with non-toxic nodular goitre with large cold nodule, aged 18 and 48 years; initial 24 h radioiodine uptake (RAIU) was ranged between 18–45%, and thyroid volume ranged between 48 and 120 ml, effective half-life was more than 3 days at the time of treatment. Malignant changes were excluded in all nodules by fine needle aspiration biopsy. The activity dose was calculated by the use of Marinelli’s formula and ranged between 280 and 800 MBq. Thyroid ultrasonography, and thyroid scan with RAIU at 24 was done before and after 6 and 12 months of RIT. Follow up control was done every 6 weeks.

Results: After 6 months RIT in all the patients the large cold nodule changes to hot nodule. In 13 patients the size of the thyroid gland decrease to 48%, and no need for the second dose of radioiodine therapy. 27 patients received second dose of RIT to decrease the nodule which was cold and turned to hot after the first dose. After 12 months of the second dose of radioiodine a mean thyroid volume reduction of 56% was achieved. After 12 months of RIT euthyroidism persist in 52% of patients, and hypothyroidism develop in 48% of patients.

Conclusions: Radioiodine is non-invasive, safe and cost effective method of therapy for reduction of large non-toxic goitre even with cold nodule. The reduction of the cold nodule and the thyroid volume, were due to well accurate measurement of administered activity, relatively high effective half-life and well-organised follow up.