Evaluation of the clinical results of thyroidectomy and RAİ treatment in the definitive treatment of Graves' disease

Background: Graves' disease (GD) is characterized by the presence of circulating TSH receptor antibodies (TRAb) in the blood and is currently the most common cause of hyperthyroidism. Graves' Ophthalmopathy (GO), an autoimmune disease of retro-ocular tissues that occurs in patients with Graves', is the most common extrathyroidal symptom of the disease. Approximately 20-25% of patients with Graves' hyperthyroidism have clinically significant Graves' ophthalmopathy, whereas only 5% have moderate to severe GO. The pathogenesis of GH and GO are related to each other, and the course of GO influences the choice of treatment modality. There are three treatment modalities for Graves' Disease: Anthyroid drugs and definite treatment modalities, RAI, and surgical treatment. In this study, we aimed to compare the effects of RAI and surgical treatment modalities used in the definitive treatment of the patients with Graves' disease who have symptoms of the disease and Graves' ophthalmopathy. Materials and Methods: Definitive treatment was planned for 119 patients with the diagnosis of Graves' Disease decided in the multidisciplinary endocrine council between January 2015 and December 2020 at Akdeniz University Faculty of Medicine. Patients with GO who had eye examination in the ophthalmology outpatient clinic before and after definitive treatment were included in the study. Demographic, clinical, pathological and outcome data were collected from the hospital computer database. Results: Patients in the RAI group were older than the surgical group (49.6 and 41.8 p=.005). There was a significant difference between the two groups in the presence of Graves' ophthalmopathy (surgical 75,4% RAI 32,6% p=0.0001). After the first dose of RAI, 69,5% of the patients had remission. The overall remission rate after additional RAI was 95,6%. Total thyroidectomy was performed in all of the patients in the surgical group. GO was remarkable with a rate of 42,1% among the surgical treatment indications. Ocular symptoms were evaluated with CAS, disease severity and proptosis. After definitive treatment, GO progression was observed at a rate of 21,8% (n=10) in the RAI group and 8,8% (n=5) in the surgical group. Conclusion: In this study, we evaluated the clinical responses of definitive treatment modalities in Graves' disease. The surgical treatment in Graves' disease had a higher success rate compared to RAI treatment in cases with active GO. The surgery should be considered as the primary treatment as the definitive treatment in patients with active GO. At the same time, CAS was found to be more valuable than other parameters in the evaluation of treatment response in both groups.