Abnormally Increased F-18 FDG PET Uptake in the Post-Partial Glossectomy Tongue on Delayed Images

F-18 FDG PET is effective for determining recurrence or treatment response of the head and neck cancer, but also some false-positive appearances are reported. Here we presented a patient of left tongue squamous cell carcinoma after partial glossectomy without concurrent chemoradiotherapy. After more than two years follow-up, he received right neck dissection because of recurrence and lymph nodes metastases, and underwent a FDG PET scan for distant metastasis survey. Although no abnormality in the tongue on initial PET imaging, high uptake of FDG in the left part of the remaining tongue mimicking a recurrent tumor was noted on delayed imaging. No recurrent tongue cancer was observed in a continuous follow-up. High FDG uptake in the tongue was presumed the result of altered balance in lingual muscle activity after operation in this patient.