a) 55-year-old patient with recurrent lip carcinoma. A malignant lesion in the left parapharyngeal space (short arrow) is suggested by misregistration caused by involuntary patient movement. The presumed tumor cannot be assessed in its entirety due to artifacts of metallic dental implants.
b) 41-year-old patient with intraorbital metastasis of a nasal squamous cell carcinoma. The tumor cannot be differentiated from the metabolically active medial rectus muscle.
c) 64-year-old female patient with CUP syndrome. Histologically proven carcinoma of the left pharyngeal tonsil. The SUV of the tumor was below the SUV of the intrinsic muscle of the tongue due to its low affinity to FDG.