TY - JOUR T1 - <sup>18</sup>F-FDG PET for the Diagnosis and Grading of Soft-Tissue Sarcoma: A Meta-Analysis JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 717 LP - 724 VL - 44 IS - 5 AU - John P.A. Ioannidis AU - Joseph Lau Y1 - 2003/05/01 UR - http://jnm.snmjournals.org/content/44/5/717.abstract N2 - PET using 18F-FDG is increasingly used for the diagnosis and grading of tumors. Several studies have been performed that evaluate the diagnostic and grading performance of 18F-FDG PET for soft-tissue sarcoma, but each study has had a limited sample size. Therefore, we undertook a comprehensive meta-analysis of the evidence. Methods: Relevant studies were identified from MEDLINE and EMBASE. Diagnostic and grading performance were evaluated for qualitative visualization; standard uptake value (SUV, cutoffs of 2.0 and 3.0); and metabolic rate of glucose (MRG, cutoff of 6.0 μmol/100 g/min). Quantitative data synthesis included independent weighting of sensitivity and specificity, construction of summary receiver operating characteristic curves, and pooled analyses. Results: The meta-analysis included 15 studies with 441 soft-tissue lesions (227 malignant, 214 benign). For diagnosis of malignant versus benign lesions, typical pairs of sensitivity and specificity estimates from the summary receiver operating characteristic curves were 92% and 73% for qualitative visualization; 87% and 79% for SUV 2.0; 70% and 87% for SUV 3.0; and 74% and 73% for MRG 6.0. Diagnostic performance was similar for primary and recurrent lesions. By qualitative interpretation, 18F-FDG was positive in all intermediate/high-grade tumors (95% confidence interval [CI], 97.3%–100%), 74.4% (95% CI, 58.6%–85.9%) of low-grade tumors, and 39.3% (95% CI, 29.1%–50.3%) of benign lesions (including 11 of 12 inflammatory lesions). Using an SUV cutoff of 2.0, respective rates were 89.4% (95% CI, 79.4%–95.6%), 33.1% (95% CI, 15.6%–55.3%), and 19.1% (95% CI, 10.6%–30.5%). Limited data on comparisons with MRI and CT showed no differences against 18F-FDG PET in diagnosing recurrent and metastatic disease. Conclusion: 18F-FDG PET has very good discriminating ability in the evaluation of both primary and recurrent soft-tissue lesions. 18F-FDG PET may be helpful in tumor grading but offers inadequate discrimination between low-grade tumors and benign lesions. ER -