Papillary thyroid cancer and chronic lymphocytic thyroiditis presenting with diffuse microcalcifications without focal mass on ultrasound

Abstract

The detection and characterization of PTC are based on the evaluation of specific ultrasonographic features of thyroid nodes. However, there is limited data regarding diagnostics without typical malignant-appearing nodules. We report a very rare case of PTC in underlying chronic lymphocytic thyroiditis ultrasonographically manifested with diffuse microcalcification without focal mass. A 22-year-old woman visited our institution complaining of weight loss, general weakness, and headache. A physical examination revealed a painless, firm thyroid without a palpable mass. In an ultrasonography of the neck, the pathology was not assessed. The thyroid hormones concentration, TPOAb (Thyroperoxidase Antibodies) were within normal ranges. Thus, we did not find any evidence of thyroid disease. Two years later, the woman made an appointment at our clinic complaining of exercise – associated dyspnea. Her thyroid-stimulating hormone (9.96 mU/l; normal, 0.4–3.6 mU/l) and TPOAb (685 kU/l; normal, 0–78 kU/l) were increased. The ultrasonography showed marked bilateral low parenchymal echogenicity, inhomogeneous thyroid. In the left thyroid lobe, there were diffuse microcalcifications without focal mass. Sonographically, the thyroid lesions were indicative of chronic lymphocytic thyroiditis. A subsequent fine needle aspiration biopsy was performed. The cytologic examination assessed a suspicion of malignancy with chronic lymphocytic thyroiditis. The patient underwent the total thyroidectomy with lymph node dissection. Histopathologically, a chronic lymphocytic thyroiditis and 0.7 cm size papillary microcarcinoma in the left lobe were detected. Numerous stromal psammoma bodies, lymphatic intralobular spread with lymph node metastasis were revealed. We have demonstrated a very rare case of PTC with chronic lymphocytic thyroiditis ultrasonographically presenting with diffuse microcalcification without thyroid nodes. In our case, an