Successful reduction in thyroid and nodule volumes in large solitary and multinodular goiters with serial 131 iodine therapy

ABSTRACT

Introduction@#131Iodine therapy is effective in nodular nontoxic goiter with enhanced effects using recombinant thyroid stimulating hormone (rTSH). The eventual fibrosis of the thyroid tissue and blood vessels ligates the vascular supply of the nodule. The study aims to show the successful reduction of thyroid and nodule volumes in large solitary and multinodular goiters using serial low dose 131iodine therapy (10mCi) at three to six months interval.@*Methods@#A retrospective analytical study was done from January 2010 to December 2012 and included twenty three patients with enlarged solitary and multinodular (nodule/s ≥2cm) non-toxic goiter (females: age range 35-65yrs) given serial 131iodine therapy (eight to10mCi) at three to six-month interval. Before each course, serum thyroid stimulating hormone (TSH) was done to document hypothyroidism while thyroid gland and nodule sizes were monitored by ultrasonographic measurements serially with each 131iodine therapy. Relief of compressive symptoms was monitored on follow-up at clinic.@*Results@#Thyroid size reduced by 38-40% from baseline after first radioactive iodine (RAI) and by 33-39% after the second RAI. Thyroid nodules reduced by 63-69% and 11-25% serially. Significant reduction was noted after the first RAI. One subject underwent third RAI with 80-85% overall reduction in nodule size. All patients developed post-RAI hypothyroidism and overall had greater than 50% increase in levothyroxine replacement dose after the last RAI. Significant relief of compressive symptoms was noted by 91% post-therapy. Four thyroid nodules disappeared which resulted in reduced total number of thyroid nodules from 29 to 25 nodules post serial RAI.@*Conclusion@#Serial 131iodine therapy proved to have thyroid and nodule size reduction by more than 70% in this study. Among patients who do not consent or have contraindications to surgery, serial 131iodine therapy may be considered a safe and effective non-surgical alternative.