Is 18F-FDG PET useful in predicting the WHO grade of malignancy in thymic epithelial tumors? A meta-analysis

• Published in: Lung cancer (Amsterdam, Netherlands) Vol. 86; no. 1; pp. 5 - 13
• Main Authors: Treglia, Giorgio, Sadeghi, Ramin, Giovanella, Luca, Cafarotti, Stefano, Filosso, Pierluigi, Lococo, Filippo
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ireland Ltd 01-10-2014; Elsevier
• Subjects: Biological and medical sciences; FDG; Medical sciences; Meta-analysis; Multiple tumors. Solid tumors. Tumors in childhood (general aspects); PET/CT; Pneumology; Positron emission tomography; Thymic; Thymoma; Tumors; Tumors of the respiratory system and mediastinum; FDG; Thymic; Thymoma; Positron emission tomography; PET/CT; Meta-analysis; Radionuclide study; 2-deoxy-2-fluoroglucose; Mediastinum disease; Lung cancer; Malignancy; Glucose; Evidence-based medicine; Metaanalysis; Thymus pathology; Bronchus disease; Benign neoplasm; WHO; Lung disease; Thymus gland; Radiodiagnosis; Respiratory disease; Evidence-based practice; Malignant tumor; Medical imagery; Computerized axial tomography; Thymic epithelial tumor; Cancer; Emission tomography
• ISSN: 0169-5002; 1872-8332
• DOI: 10.1016/j.lungcan.2014.08.008

•A pre-op identification of the WHO-subtype of thymic tumors has important implications on the overall management strategy.•18F-FDG PET/CT findings correlate with the aggressiveness, proliferative activity and prognosis of TETs.•The present meta-analysis clearly shows that 18F-FDG PET/CT may predict the WHO-grade of malignancy in TETs.
To perform a systematic review and meta-analysis of published data on the role of fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET) in predicting the WHO grade of malignancy in thymic epithelial tumors (TETs).
A comprehensive literature search of studies published up to March 2014 was performed. Data on maximum standardized uptake value (SUVmax) in patients with low-risk thymomas (A, AB, B1), high-risk thymomas (B2, B3) and thymic carcinomas (C) according to the WHO classification were collected when reported by the retrieved articles. The comparison of mean SUVmax between low-risk thymomas, high-risk thymomas and thymic carcinomas was expressed as weighted mean difference (WMD) and a pooled WMD was calculated including 95% confidence interval (95%CI).
Eleven studies were selected for the meta-analysis. The pooled WMD of SUVmax between high-risk and low-risk thymomas was 1.2 (95%CI: 0.4–2.0). The pooled WMD of SUVmax between thymic carcinomas and low-risk thymomas was 4.8 (95%CI: 3.4–6.1). Finally, the pooled WMD of SUVmax between thymic carcinomas and high-risk thymomas was 3.5 (95%CI: 2.7–4.3).
18F-FDG PET may predict the WHO grade of malignancy in TETs. In particular, we demonstrated a statistically significant difference of SUVmax between the different TETs (low-grade thymomas, high-grade thymomas and thymic carcinomas).