Pertechnetate Thyroid Scan and Thyroid Function Tests in a Case of Sorafenib Induced Thyroiditis

Abstract

Purpose of report:Sorafenib is a tyrosine kinase inhibitor used for treatment of advanced metastatic renal cell carcinoma and in recent years, for patients suffering from hepatocellular carcinoma (HCC) with limited options. Thyroiditis is a relatively rare side effect and we present one such case.Materials and Methods:We describe a 65 year old male undergoing Sorafenib treatment for advanced HCC, who developed thyroid abnormalities clinically and biochemically. Thyroid Function Tests followed over 6 months and a Tc-99m Pertechnetate scan were performed for diagnosis and evaluation.Results:The temporal connection between onset of clinical and biochemical hyperthyroidism with commencement of Sorafenib therapy in a patient with no history of thyroid disease aroused suspicions for a drug induced reaction. Follow-up over 6 months using TFTs and the thyroid scan confirms a thyroiditis with subclinical hypothyroidism that was preceded by a hyperthyroid phase.Conclusion:Correlation between TFTs and thyroid scans are useful in patients on Sorafenib therapy especially if there are clinical signs or if patients have risk factors of advanced age, prior thyroid disease or neck irradiation.