Establishing and Monitoring an Effective Management of Benign Nontoxic Multinodular Goitre in Kuwait "Utilizing Two Different Dose Levels of Recombinant Human TSH in Combination with Radioactive Iodine".

Introduction: rhTSH-assisted radioiodine therapy of multinodular goiter is not fully known and only a few studies, with a limited number of patients have evaluated the effect of rhTSH assisted radioiodine therapy beyond 1 year. Though there is an effective and safe management of benign non-toxic MNG available, it is not applicable to all patient categories in Kuwait covering the impact of the past environmental events (Gulf War) and the genetic relation. The proposed project aims to address those points raised, that is exclusive to the Kuwait population.

Materials and methods: In this cohort study, 2 groups of patients, group one (G1) and group two (G2) patients (N=50, ≥18 years old) went undergo evaluated according to a proposed criteria followed by FNA to exclude cancer, toxicity and those who have refused surgery. All patients had a CT scan, TSH, T3, T4 and CBC and complete biomedical tests at a 6-months interval during the treatment period and the follow up. The Volumetric application of GE 670 SPECT/CT (i.e. Xeleris) and in-house developed MATLAB used for quantitative measurement. All patients had a 131-I uptake at baseline and 24 intervals post intramuscular a single dose of 0.3mg or 0.1mg (group 1, group 2) of rhTSH.

Results: There was no significant difference in TSH levels at 24-month follow-up between the two groups (p=0.327), whereas there was a statistically significant difference at the baseline and at the 6-months interval between the 2 groups for T4. Post treatment follow up at the 24-hour time point, Group 1 displayed significantly higher uptake than Group 2 (G1:41.74 ± 6.27 vs. G2:34.80 ± 3.84, p < 0.001). The change in I131 uptake from baseline to 24 hours was significantly greater in Group 1compared to Group 2 (p < 0.001). The ROC analysis (AUC) post treatment indicated an excellent discriminatory power for AUC (0.960) and (p < 0.001). There was a much better correlation posttreatment between BMI and thyroid volume for group 1 (R2=0.661) than for group 2 (R2=0.008). Our results suggest 42.1% thyroid volume reduction for group 1 and 20% for group 2.

Conclusion: The study underscores the potential benefits of the higher rhTSH dose (0.3mg) in managing multinodular non-toxic goiter for the Kuwaiti population and the region considering the impact of dietary, and experience to the drastic environmental exposure.