S. U. Berlangieri

Role of Low-dose, Noncontrast Computed Tomography from Integrated Positron Emission Tomography/Computed Tomography in Evaluating Incidental 2-Deoxy-2-[F-18]fluoro-d-glucose-avid Colon Lesions

PurposeTo assess the contribution of concurrent low-dose, noncontrast CT in the assessment of the malignant potential of incidental focal 2-deoxy-2-[F-18]fluoro-d-glucose (FDG)-avid colonic lesions on positron emission tomography/computed tomography (PET/CT).ProceduresRoutine FDG-PET/CT scans were reviewed for identification of focal FDG-avid colon lesions, and the CT component was independently reviewed for an anatomical lesion and malignant potential based on CT criteria. Clinical, endoscopic, and histopathology follow-up was obtained.ResultsA total of 85/2,916 (3%) oncology FDG-PET/CT scans had incidental focal colon lesions. Clinical and/or endoscopic follow-up was available in 83/85 (98%) patients. Focal, corresponding CT lesions were found in 44/83 (53%) patients, but features of malignancy were not assessable. Of the 44 patients with a final diagnosis, 32/44 (73%) were FDG-PET/CT true positives; 5/44 (11%) were false positives; and 7/44 (16%) had inconclusive FDG-PET/CT findings.ConclusionsConcurrent low-dose, noncontrast CT improves localization, but does not provide independent information on the malignant potential of incidental focal colonic activity on FDG-PET/CT.

Prevalence of occult metastatic disease in patients undergoing 18F-FDG PET for primary diagnosis or staging of lung carcinoma and solitary pulmonary nodules.

Background: Accurate staging of lung cancer is essential in determining the most appropriate management plan, as detection of occult metastasis can significantly alter management.

F-18 fluorodeoxyglucose PET and Ga-67 citrate scintigraphy in a case of AIDS lymphoma and pericarditis

A 32-year-old patient with AIDS was examined by Ga-67 citrate and F-18 FDG PET to stage biopsy-proved gastric non-Hodgkins lymphoma. The Ga-67 scan showed increased uptake in the stomach, lungs, and pericardium. The PET study was consistent with lymphomatous involvement in the stomach and lung apices, but no abnormality was evident in the pericardium. The pericardium was not examined by biopsy given the absence of significant symptoms and no large pericardial effusion. The disparity between the Ga-67 and the FDG findings in this region suggested an inflammatory process rather than lymphomatous involvement and highlights the multiple diseases encountered in patients with AIDS.