Papillary thyroid carcinoma with honeycomb-like multiple small cysts: characteristic features on ultrasonography.

BACKGROUND Thyroid nodules with cystic content or mixed sponge-like aspect on ultrasonography and a concordant cytology are strongly predictive of benignity. OBJECTIVES We present 8 patients with honeycomb-like papillary thyroid carcinoma with multiple small cysts on ultrasonography. METHODS The patients were 6 women and 2 men aged between 30 and 57 years. The tumors of these patients showed honeycomb-like multiple small cysts that were aggregated in some area of the thyroid gland on ultrasonography. Histopathological examination indicated a well-differentiated type of papillary thyroid carcinoma with multiple small cysts and a small solid lesion. The cysts were lined with papillary carcinoma cells, and normal thyroid tissue lay between the cysts. RESULTS There is a peculiar type of papillary thyroid carcinoma that histopathologically shows honeycomb-like multiple small cysts in the thyroid gland. Ultrasonography can be used to identify characteristic features of honeycomb-like multiple small cysts in the thyroid gland in such patients. CONCLUSIONS One should be aware of this peculiar type of papillary thyroid carcinoma with honeycomb-like multiple small cysts on ultrasonography, although thyroid nodules with cystic lesions are generally regarded as benign in clinical management.