Review of six cases of false-positive FDG-PET findings revealing non-recurrent lesions following lung cancer surgery

Abstract

Fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) for the preoperative diagnosis of lung cancer has been reported to be more accurate than computed tomography. It is useful for the differentiation between benign and malignant tumors and for locating lymph node or distant metastasis. As a result, FDG-PET is being used increasingly frequently for the diagnosis of recurrent lesions. However, FDG-PET can also yield false-positives and-negatives, posing problems in diagnosis. We reviewed six cases in which a positive FDG-PET finding revealed non-recurrent lesions. Of the six cases, three involved infectious disease, all of which were treated with chemotherapy. In one case thoracotomy revealed suspected intercostal and subcutaneous tumor dissemination, but the final diagnosis was inflammatory granulation tissue. Based on these six cases, false-positive FDG-PET findings can be useful in the detection of infectious foci or additional tumors, leading to a definite diagnosis by thoracotomy or video-assisted thoracoscopic surgery.