Pleomorphic Adenoma Mimicking Malignant Tumor in the Parapharyngeal Space in a Patient with Gastric Carcinoma

A 68-year-old man underwent total gastrectomy for stomach cancer. On the follow-up FDG PET/CT image 18 months later, intense focal (18)F-fluorodeoxyglucose (FDG) uptake was noted in the right parapharyngeal space. This lesion showed intermediate signal intensity on T1-weighted image and heterogeneous high signal intensity on T2-weighted image. The mass was heterogenously enhanced by gadolinium enhancement. This lesion was pathologically confirmed as pleomorphic adenoma by excision. This case highlights the fact that both benign and malignant lesions in the parotid gland may exhibit intense FDG activity and the need for pathologic confirmation of parotid gland lesions for accurate disease staging.