Pharyngeal cancer. Positron emission tomography (PET) coronal scan of a patient with a primary cancer of the pharynx, the part of the throat behind the nose and mouth. The primary tumour (white) is the area in the centre of the neck, highlighted by the use of a contrast medium. The contrast medium has also highlighted a metastatic spread of the cancer to lymph nodes (white) on the left side of the neck (at right in this view from the front). The brain is also highlighted, as are traces of the contrast medium in the kidneys.