Bronchiectasis as a Cause of Elevated CA-19-9 Demonstrated on 18F-FDG PET/CT.

A 64-year-old woman with a history of weight loss and a markedly elevated serum carbohydrate antigen 19-9 level of 560 U/mL was referred for an F-FDG PET study to evaluate for occult malignancy. In addition to the weight loss, she had suffered from a chronic cough secondary to bronchiectasis and had been investigated for a suspected gastrointestinal malignancy. Multiple FDG-avid foci were detected throughout both lungs on FDG PET, corresponding to areas of bronchiectasis on CT with no obvious suspicious FDG-avid foci elsewhere. This supported an inflammatory process causing her elevated carbohydrate antigen 19-9 rather than malignancy.