Utility of PET/CT in Differentiating Benign from Malignant Adrenal Nodules in Patients with Cancer
- 1 November 2008
- journal article
- Published by American Roentgen Ray Society in American Journal of Roentgenology
- Vol. 191 (5), 1545-1551
- https://doi.org/10.2214/ajr.07.3447
Abstract
OBJECTIVE. The purpose of this retrospective study was to determine the sensitivity and specificity of combined PET/CT in differentiating benign from malignant adrenal nodules measuring at least 1 cm in diameter in patients with cancer. MATERIALS AND METHODS. We reviewed the radiology reports and images of patients with known malignant disease who had undergone PET/CT for cancer staging or surveillance and who had adrenal nodules at least 1 cm in diameter. We identified 112 adrenal nodules in 96 patients. Two-dimensional PET had been performed 1 hour after administration of 18F-FDG. Unenhanced CT was performed for attenuation correction, to determine lesion size, and for coregistration with PET data. Adrenal nodules were considered to have a positive PET result if the average standardized uptake value was greater than that of the liver. Follow-up data and biopsy reports were used to determine the pathologic status of the adrenal nodules. RESULTS. Thirty adrenal lesions were malignant. Twenty-five of the 30 malignant nodules had positive PET results. Twelve of 82 benign nodules were PET positive with a sensitivity of 83.3% and specificity of 85.4%. Patients with four of five malignant nodules with negative PET results had received previous therapy. The positive predictive value for detection of malignant lesions was 67%, and the negative predictive value was 93%. CONCLUSION. Adrenal masses that are not FDG avid are likely to be benign with a high negative predictive value. Especially in patients undergoing therapy, however, there is a small but statistically significant false-negative rate. A considerable proportion of benign nodules have increased FDG activity.Keywords
This publication has 28 references indexed in Scilit:
- Preoperative evaluation of adrenal lesions based on imaging studies and laparoscopic adrenalectomy in patients with otherwise operable lung cancerLung Cancer, 2007
- Integrated PET-CT for the Characterization of Adrenal Gland Lesions in Cancer Patients: Diagnostic Efficacy and Interpretation PitfallsRadioGraphics, 2006
- State-of-the-Art Adrenal ImagingRadioGraphics, 2001
- Is computed tomography guided biopsy still necessary for the diagnosis of adrenal masses in patients with resectable non-small-cell lung cancer?European Journal of Cardio-Thoracic Surgery, 1999
- Characterization of adrenal masses using unenhanced CT: an analysis of the CT literature.American Journal of Roentgenology, 1998
- Delayed enhanced CT for differentiation of benign from malignant adrenal masses.Radiology, 1996
- Distinction between benign and malignant adrenal masses: value of T1-weighted chemical-shift MR imaging.American Journal of Roentgenology, 1995
- State-of-the-art MR imaging of the adrenal gland.RadioGraphics, 1994
- The Incidentally Discovered Adrenal MassAnnals of Internal Medicine, 1983
- Metastases in carcinoma.Analysis of 1000 autopsied casesCancer, 1950