The role of ¹⁸F‐FDG PET/CT in the metabolic characterization of lung nodules in pediatric patients with bone sarcoma

Abstract

BackgroundThe principal aim of this study was to identify the lowest nodule diameter and the SUVmax capable of characterizing lung nodules in pediatric patients with bone sarcoma.ProcedureEighteen consecutive bone sarcoma patients (M/F = 11:7; mean age 14 years) with suspicious lung lesions at CT were enrolled. Overall, 63 lung nodules with a mean diameter of 3.35 mm (range 1.2–39.8 mm) were investigated. 18F‐FDG PET was performed according to standard procedure using a hybrid PET/CT system and results were compared with histology and/or clinical/radiological follow‐up. For each lesion, we evaluated SUVmax, SUVratio to the mediastinal blood pool and maximum nodule diameter.ResultsOf the 63 nodules, 32 proved to be benign and 31 malignant. On a visual basis, 18F‐FDG PET had an accuracy of 88.9%, a sensitivity of 90.3%, a specificity of 87.5%, a PPV of 87.5%, and a NPV of 90.3%. ROC curve analysis of SUVmax for all nodules showed a value around 1 (>1.09) to be capable of differentiating metastases from benign lesions: sensitivity and specificity were 90.3% and 93.8%, respectively (accuracy 92.1%). Similar analysis revealed a cut‐off value around 1 (>0.83) for SUVratio (sensitivity and specificity were 90.3% and 90.6%, respectively) and a cut‐off value of ca. 6 mm (>5.8 mm) for nodule diameter (sensitivity and specificity of 90.3% and 81.3%, respectively).Conclusions18F‐FDG PET/CT is an accurate modality for the metabolic characterization of lung nodules in the pediatric population with bone sarcoma, and a SUVmax (or SUVratio) >1 is capable of discriminating malignant from benign lesions. Pediatr Blood Cancer 2012; 59: 1206–1210. © 2012 Wiley Periodicals, Inc.

Evaluation of the Outcome of Lung Nodules Missed on 18F-FDG PET/MRI Compared with 18F-FDG PET/CT in Patients with Known Malignancies

“…Today, whole-body 18 F-FDG PET/CT is widely available and used not only to identify lung nodules but also to discriminate malignant from benign pulmonary masses, enabling a comprehensive tumor staging in a 1-stop shop examination (21)(22)(23). On the other hand, the latest transition from a mere research modality into clinical practice raised issues regarding the eligibility of 18 F-FDG PET/MRI to detect small pulmonary nodules compared with CT or PET/CT as the modality of choice for lung imaging.…”

Pediatric Malignant Bone Tumors: A Review and Update on Current Challenges, and Emerging Drug Targets

“…A recent study using Fluorine-18-fluorodeoxyglucose positron emission tomography ( 18 F-FDG PET) suggests that the PET avidity (SUV max 4 1) of nodules above 6 mm is consistent with malignancy. 18 Traditionally bone scans have been used to detect bone metastasis; however, in the future PET/CT and/or PET/MRI may supplant the routine use of bone scan. 18,19 Laboratory Testing Generally, the CBC and blood chemistries are normal in patients with OS and provide a valuable baseline, as they may be perturbed once therapy is initiated.…”

Pulmonary and Extrathymic Mediastinal Tumors

“…There may be a limited role for FDG-PET in improving the specificity for malignancy in enlarged lymph nodes or lung nodules visualized on CT (Kleis et al 2009;Cistaro et al 2012).…”

“…FDG-PET confers significantly higher specificity than CT for pulmonary metastases greater than 5 mm diameter in children (Kleis et al 2009). A prospective study of FDG-PET/CT in the characterization of pulmonary nodules in children with bone sarcoma demonstrated a sensitivity of 90 % and specificity of 94 % using a SUV max value around 1, compared to a sensitivity of 90 % and specificity of 81 % using a cut-off value of 6 mm for nodule diameter (Cistaro et al 2012).…”