ABSTRACT
PURPOSE: To 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). PROCEDURES: Routine 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. RESULTS: A 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. CONCLUSIONS: Concurrent 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.
Subject(s)
Colonic Diseases/diagnosis , Contrast Media/metabolism , Fluorodeoxyglucose F18 , Incidental Findings , Positron-Emission Tomography , Tomography, X-Ray Computed , Endoscopy , False Positive Reactions , Follow-Up Studies , HumansABSTRACT
BACKGROUND: Accurate staging of lung cancer is essential in determining the most appropriate management plan, as detection of occult metastasis can significantly alter management. AIMS: The aims of this study are to determine the prevalence of occult metastasis in patients undergoing 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography (PET) for evaluation of suspected/proven lung carcinoma and correlate pre-PET TNM stage with prevalence of metastasis. METHODS: FDG-PET, which identified patients with metastasis on institutional database, was re-evaluated by a nuclear medicine physician blinded to clinical information. The confidence level of metastasis was scored on a 5-point scale, with a score of >/=4 considered positive. RESULTS: There were 67 of 645 (10%) patients identified with suspected occult metastasis on FDG-PET. Twelve patients scoring
Subject(s)
Lung Neoplasms/diagnostic imaging , Lung Neoplasms/epidemiology , Neoplasm Metastasis/diagnostic imaging , Solitary Pulmonary Nodule/diagnostic imaging , Solitary Pulmonary Nodule/epidemiology , Adult , Aged , Aged, 80 and over , Female , Fluorodeoxyglucose F18 , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Positron-Emission Tomography , Predictive Value of Tests , Prevalence , Radiopharmaceuticals , Retrospective Studies , Solitary Pulmonary Nodule/pathologyABSTRACT
Fluorine-18 fluorothymidine (F-18 FLT) is a radioisotope based on the nucleic acid thymidine and has emerged as an important tracer that mirrors cellular proliferation in positron emission tomography (PET) studies. Early studies in human tumors have been promising. However, imaging of renal tumors using F-18 FLT PET studies has not previously been described. In this report, a difficult case of renal transitional cell carcinoma in a longstanding cyst was clearly delineated using F-18 FLT. Importantly, the study was able to guide clinicians toward appropriate surgical management. The use of such tracers may herald a new era in renal tumor imaging.
