Cervical Nontuberculous Mycobacterial Lymphadenitis Mimicking a Thyroid Tumor and Infiltrating Deep into the Neck

Aim: Nontuberculous Mycobacterial Lymphadenitis (NML), which occurs in 1.2 per 100,000 children, is very rare. And those which emerge at the anterior cervical portion and infiltrate deep into the neck are even more rare. Generally, this disorder is uncommon existed near the thyroid gland. We report here a case of NML mimicking a thyroid tumor and infiltrating into the deep part of the anterior neck. Case: A mass at the anterior portion of her neck was found at 5 years old. It was not mobile and palpated as an irregularly surfaced hard mass whose size was 3 cm at the anterior lower portion of her neck. Ultrasonography showed an oval mass which existed near the slightly inferior part of the right lobe of the thyroid gland. Enhanced computed tomography showed a mass near the slightly inferior part of the right lobe of the thyroid gland. The mass was resected with the platysma and the right sternohyoid muscle. In the HE staining, epithelioid cell and Langhans type giant cells surrounding coagulative necrosis lesions which seemed to be caseation necrosis existed, similarly to cervical NML. Discussion: No consensus exists for the treatment of NML, but many documents advise complete excision. When the lesion cannot be completely removed, excision as far as possible and additional antibiotics are recommended. The characteristics of imaging of NML around the thyroid gland and infiltrating deep into the anterior neck and mediastinum are discussed.