Metastatic Head and Neck Cancer Conflated with Pulmonary Embolism and Infarct on PET/CT

The use of FDG PET/CT in the assessment of oncologic disease is becoming increasingly widespread. The advent of PET/CT however presents some additional challenges; recent reports have emphasized the need to detect incidental findings which can confer additional health risks. We report a case of a pulmonary embolus with pulmonary infarct secondary to a metastatic right atrial mass on a background of squamous cell carcinoma of the neck that demonstrated findings on both the PET and CT portions of the examination. The significance of standardized uptake value (SUV) in the differential diagnosis of chest lesions is discussed. This report highlights the possible co-existence of non-metastatic, but potentially life threatening abnormalities that may be present on the CT portion of such studies.