Abstract
A 59-year-old male with T2N0M0 carcinoma of the right oral floor of the mouth underwent partial excision of the oral floor and partial mandibulectomy. Forty months after the initial surgery, late cervical lymph node metastases developed in the right upper neck. FDG-PET scan revealed high uptake in the right neck as well as the bilateral pulmonary apexes, mimicking malignancy. Chemotherapy resulted in a temporary reduction of FDG uptake in both those regions. Thereafter the cervical nodes enlarged, however SUVmax in the lung decreased. Modified radical neck dissection was performed, and finally nontuberculous mycobacterial avium complex (MAC) was detected. There has been no evidence of recurrence or metastasis in the 87 months after the initial surgery and in the 40 months after the neck dissection. The incidence of pulmonary MAC infection is increasing. It is notable that the PET image of MAC infection is similar to that of pulmonary metastases and lung malignancy.
