RT Journal Article SR Electronic T1 Significance of Incidental 18F-FDG Accumulations in the Gastrointestinal Tract in PET/CT: Correlation with Endoscopic and Histopathologic Results JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1804 OP 1810 VO 45 IS 11 A1 Ehab M. Kamel A1 Miriam Thumshirn A1 Kaspar Truninger A1 Marc Schiesser A1 Michael Fried A1 Barbara Padberg A1 Didier Schneiter A1 Sandro J. Stoeckli A1 Gustav K. von Schulthess A1 Katrin D.M. Stumpe YR 2004 UL http://jnm.snmjournals.org/content/45/11/1804.abstract AB This study was undertaken to identify the clinical value of incidentally detected lesions (IDLs) in the gastrointestinal tract (GIT) with 18F-FDG PET/CT. Methods: The reported database of 3,281 patients who underwent partial-body 18F-FDG PET/CT scans from April 2001 to September 2003 was reviewed. Patients with incidental 18F-FDG accumulations in the GIT that were associated with concomitant abnormal soft-tissue density or wall thickening on the native CT were evaluated. Incidental PET/CT findings were correlated with endoscopic and histopathologic results. Results: According to our selection criteria, 98 (3%) of the 3,281 patients had an IDL of the GIT on 18F-FDG PET/CT. Correlative endoscopic findings were available in 69 (70%) of 98 patients. Of these, 13 patients (19%) were harboring newly occurring cancers of the GIT in addition to preexisting aerodigestive tract tumors (n = 12) and malignant melanoma (n = 1). Twenty-nine (42%) patients were identified with precancerous lesions, such as advanced colonic adenomas (n = 27), Barrett’s esophagus (n = 1), and intestinal metaplasia of the gastric mucosa (n = 1). Inflammatory and other benign GIT lesions were detected in 12 (17%) and 6 (8%) patients, respectively. In 9 (13%) patients, PET/CT was false-positive, showing normal findings in subsequent endoscopic examinations. In 20 (28%) of 69 patients, PET/CT findings had a relevant impact on the clinical management. Twenty-nine (30%) of the 98 patients were not subject to a further endoscopic examination because of the extent and nature of the primary tumor (n = 17), loss to follow-up (n = 7), death shortly after PET (n = 3), and patient unwillingness (n = 2). Conclusion: Although IDLs of the GIT on 18F-FDG PET/CT scans are found only in about 3% of cases, they are associated with a substantial risk of an underlying cancerous or precancerous lesion. Early identification of these occult lesions may have a major impact on the patients’ management and outcome.