Anaplastic Thyroid Carcinoma Following Radioactive Iodine Therapy for Graves' Disease
A 42-year-old woman was referred to our clinic in 1998, because of palpitations, hand tremor, and laboratory findings of hyperthyroidism (serum thyrotropin [thyroid-stimulating hormone, TSH] 0.05 µIU/mL [reference range, 0.17 to 4.05], free thyroxine 4.01 ng/dL [reference range, 0.79 to 1.86], and positive TSH receptor antibody at 201.7% [percent binding inhibition index, radioreceptor assay, reference range; ±15.0%]), and had been diagnosed as Graves' disease. A technetium-99m thyroid scan showed enlarged and homogeneously increased uptake, and ultrasonography revealed a diffuse goiter without nodules. The patient received 200 mg/day of propylthiouracil and β-adrenergic blocking agents for 1 year. However, due to recurrent hyperthyroidism, she received RAI therapy twice with an administered dose 370 MBq (10 mCi), 296 MBq (8 mCi), each. Two years later, she received thyroid hormone replacement due to subsequent hypothyroidism at a local clinic.\nIn September 2010, over 10 years later, she revisited us with complaints of hoarseness, dysphagia, and dyspnea, which had been presented for 2 months. An anterior neck mass, which was hard and fixed, and some lymph nodes (LNs) around the mass were palpable. Her chest radiography showed a tracheal narrowing and deviation to the right without active lung lesion. On computed tomography (CT) of the neck, the thyroidal mass invaded the tracheal cartilage and the right tracheoesophageal groove (). In fludeoxyglucose positron emission tomography-CT, an intense hypermetabolic lesion was noted in the thyroid gland and LNs on her left neck without distant metastasis. LN biopsy was performed and microscopically showed metastatic papillary carcinoma (). In September 2010, a total thyroidectomy with selective neck dissection, tracheal sleeve resection, and end-to-end anastomosis were performed. The surgical specimen from the thyroid was diagnosed as anaplastic carcinoma (). The final pathologic staging was T4bN1bM0. Subsequently, she had concurrent cisplatin-based chemoradiotherapy for her neck and superior mediastinum (total 6,600 cGy/33 fractions).\nAfter 4 months of follow-up, despite the aggressive treatment, the disease progressed. She developed shortness of breath, dyspnea, and pain in her left arm. On neck CT, a new focal necrotic mass on the left side of her neck was noted, suggesting local recurrence. The mass extended up to the tracheal lumen and the patient died of sudden uncontrolled bleeding in the airway.