Intrathyroidal ectopic thymus in 8-year-old girl: a case report.

We provide a case report of two thyroid nodules in an 8-year-old girl, which revealed malignant ultrasonographic findings and which were confirmed as ectopic thymic tissue by total thyroidectomy. The ultrasound presentations of intrathyroidal thymus glands were similar to those of the malignant thyroid nodules. In addition, in this case, there were two ectopic thymus lesions in the thyroid gland, which undoubtedly increased the difficulty of diagnosis. The occurrence of multiple ectopic thymic lesions in the thyroid gland was different from previous reports. Therefore, clinicians should take into consideration this rare entity, and should not mistake it as a thyroid neoplasm; moreover, they should not perform extensive thyroid resection.