Diffuse sclerosing variant of papillary thyroid carcinoma: ultrasonographic and clinicopathological features in children/adolescents and adults

Aim: To analyse the clinicopathological features and ultrasound findings of the diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) and compare differences between children/adolescents (CAs) and adults.

Materials and methods: Medical records and ultrasound images of 97 consecutive DSV-PTC patients were reviewed and comparison was made between CAs and adults.

Results: The average age was 31.2 ± 12.4 years old and 16.5% patients were CAs. Unilateral lobe was involved in 40.2% patients and 69.1% combined with Hashimoto's thyroiditis. Up to 95.9% patients had lymph node metastasis (LNM). CAs had more contralateral central LNM (CCLNM) and contralateral lateral LNM (CLLNM) than adults (p=0.047, p=0.025). Lung metastasis was also more common in CAs (p=0.002). Involved lobes mostly appeared as diffuse heterogeneous echogenicity on ultrasonography with isoechogenicity as the most common predominant echo (48.4%). Diffuse microcalcifications were observed frequently with grade 2-3 accounting for 52.3%. Lesions involving the whole gland lobe (diffuse type) occurred in 63.9%. Blood flow was poor in 71.6% (with grade 0-1). Microcalcifications of both lobes and metastatic lymph nodes and lesions involving (diffuse type) were more common in CAs (p=0.038, 0.002; 0.011). Of 39 patients with unilateral lobe involvement, ultrasonic sensitivity for CCLNM and CLLNM was only 50% and 66.7% respectively.

Conclusion: DSV-PTC has characteristic ultrasonographic findings. DSV-PTC of CAs may be more aggressive than that of adults. Ultrasonic sensitivity for LNM of contralateral compartments was not satisfactory and diagnostic methods with good efficacy are required.