Patterns and Significance of Peripheral Calcifications of Thyroid Tumors seen on Ultrasound

PURPOSE: We wanted to analyze the peripheral calcification patterns of thyroid tumors that were seen on ultrasound and we also wanted to evaluate the clinical usefulness of the peripheral calcifications of the thyroid tumors. MATERIALS AND METHODS: We retrospectively analyzed 21 peripheral calcifications of the thyroid tumors of 18 patients; these were histopathologically confirmed by fine needle aspiration biopsy, automated gun biopsy and surgery. The peripheral calcification patterns were categorized into three types: type 1, peripheral nodular calcification, type 2, peripheral smooth rim calcification, and type 3, peripheral irregular rim calcification. The histopathologic results obtained during surgery, fine needle aspiration or automated gun biopsy were compared. RESULTS: Of the total 21 peripheral calcifications of thyroid tumors, 5 cases showed as being type 1 (24%), 3 cases showed as being type 2 (14%) and 13 cases showed as being type 3 (62%). Of the total 21 peripheral calcifications of the thyroid tumors, 18 were histopathologically confirmed as papillary carcinoma (86%). Among the type 1 peripheral calcification patterns, 3 cases were coincidentally diagnosed as papillary carcinoma and 2 cases were follicular neoplasm on the preoperative biopsy results and on the surgical results. Two cases of type 2 peripheral calcifications (67%) and three cases of type 3 peripheral calcifications (23%) were diagnosed as benign lesions upon preoperative biopsy, but the postoperative results were papillary carcinoma. CONCLUSION: Peripheral calcifications of thyroid tumors are important feature that suggest malignancy together with the microcalcification and peripheral calcifications of the type 2 and type 3 patterns, and these lesions may be difficult to accurately diagnose with using only biopsy.

Percutaneous Radiofrequency Ablation for Benign Nodules of the Thyroid Gland

PURPOSE: We wanted to evaluate the efficacy and safety of using ultrasound guided percutaneous radiofrequency ablation for the benign nodules of the thyroid gland. MATERIALS AND METHODS: We studied 148 patients with benign thyroid nodules (200 total nodules) that were confirmed histopathologically, and we performed ultrasound guided radiofrequency ablation. The radiofrequency ablation was done 1 to 5 times per one nodule, and follow-up ultrasonography was performed one to nineteen months after the ablation procedures. The physical changes and the decrease of volume of the nodules were evaluated, and the complications related to radiofrequency ablation were observed. RESULTS: The mean initial nodule volume was 0.01-95.61 ml (mean; 6.83+/-SD of 10.63 ml) and the nodule volume after radiofrequency ablation was decreased to 0.00-46.56 ml (mean; 1.83+/-SD of 4.69 ml). The mean volume reduction rate was 73.2%. Reduction of more than 50% was noted in 90% of all cases. For 180 nodules (90%), the decrease was 50% or more, in 20 nodules (10%), the decrease was 49% or less. On gray-scale ultrasonogram obtained after ablation, the echogenicity of the nodules changed to darker, and on the doppler-sonogram, the vascular flow within the nodules disappeared in all cases. Most patients complained pain during or right after the procedure, but the pain was transient and subsided after medication. Two patients developed hoarseness that was improved in 1 week and 2 months, respectively. CONCLUSION: Sonoguided percutaneous radiofrequency ablation can be one of the treatments for benign nodules of the thyroid gland.