1.

Image diagnosis

Content	Level I expert recommendation	Level II expert recommendation
CT, computed tomography; MRI, magnetic resonance imaging; PET, positron emission tomography.
Diagnosis	Primary lesion enhanced CT Primary lesion enhanced MRI Neck enhanced CT	PET/CT
Image staging (1)	Primary lesion enhanced CT Primary lesion enhanced MRI Neck enhanced CT Chest enhanced or plain CT Abdominal ultrasound	PET/CT
Technique to obtain tissue or cytology analysis	Oral or endoscopic mass biopsy Cervical lymph node puncture or biopsy	Endoscopic examination and biopsy under general anesthesia