Endocrine Abstracts

Introduction: Radioiodine (RAI) is a safe and effective treatment used to treat benign thyroid disease. A review of patients who received RAI in Malta between 2010 and 2018 was carried out to determine their outcome.

Methods: Data collection included patient demographics, indication for RAI, amount of RAI doses received, use of antithyroid drugs pre RAI and thyroid function tests (TFTs) at 3, 6 and 12 months post RAI. Cure was defined as euthyroidism or hypothyroidism during the first year post RAI.

Results: 185 patients received RAI. 136 (73.5%) were female whilst 49 (26%) were male. Average age was 52.8 years. A standard dose of 10 mCi was used. 9 patients needed a repeat dose. Indications for RAI included Graves’ disease: 113 (61%), multinodular goitre: 14 (7.5%), toxic adenoma: 12 (6.4%), amiodarone induced thyrotoxicosis: 2 (1%) and hyperthyroidism cause: 44 (23.8%). Before each RAI dose 148 (76%) were treated with carbimazole, 11 (5.7%) received propylthiouracil, 27(14%) had no treatment and in 6(3%) no treatment was recorded. Patients had their thyroid function tests checked after 3, 6 and 12 months. At 3 months: 25(12.9%) were euthyroid, 100 (51.5%) were hypothyroid, 21 (10.8%) hyperthyroid in 47 (24%) no TFTs were available. At 6 months: 19 (9.8%) were euthyroid, 115 (59%) hypothyroid, 19 (9.8%) hyperthyroid and in 40 (20.6%) TFTs were unavailable. At 12 months: 18 (9.2%) were euthyroid, 116 (59.8%) hypothyroid, 5 (2.6%) hyperthyroid and in 52 (26.8%) TFTs were unavailable. Median duration to achieve eu/hypothyroidism was as follows: 125 (64.4%): 3 months, 45 (23%): 6 months, 6 (3%): 12 months and in 13 (6.7%) no data was available. 6(3%) were still hyperthyroid at 12 months.

Discussion: The majority of patients achieve euthyroidism or hypothyroidism at one year. Radioiodine is a highly successful treatment in benign thyroid disease.