Ultrasonographic features of Langerhans cell histiocytosis of the thyroid.

Langerhans cell histiocytosis (LCH) is a rare disease, especially when it involves the thyroid gland. Awareness of ultrasonic features will be helpful for a clinician who should consider this disease in the differential diagnosis from other more common thyroid disorders, especially prior to surgery. Here, we report two patients who have histologically confirmed LCH of the thyroid and summarize the reported cases with ultrasonographic scans from the last 10 years (n=10). Ultrasonograms showed isolated or multiple hypoechoic nodules in unilateral or bilateral thyroid gland. Internal acoustic features of most nodules was heterogeneous (n=5) or hypoechoic (n=2).