Various diagnostic tools were used in 26 patients with parotid masses to determine their value in preoperative malignant or benign categorization. These tools were positron emission tomography (PET), clinical examination, fine-needle aspiration biopsy (FNAB), computed tomography (CT), and magnetic resonance imaging (MRI). PET identified all 26 lesions and all 12 malignant lesions, but made the correct categorization in only 69% of cases. Thus, it was not as good as the more conventional diagnostic methods, their correct categorizations being 85% (clinical), 87% (CT/MRI), and 78% (FNAB) in the same patients.