Differentiation of soft tissue and bone sarcomas from benign lesions utilizing 18F-FDG PET/CT-derived parameters

Abstract

Background Accurate differentiation between malignant and benign changes in soft tissue and bone lesions is essential for the prevention of unnecessary biopsies and surgical resection. Nevertheless, it remains a challenge and a standard diagnosis modality is urgently needed. The objective of this study was to evaluate the usefulness of 18 F-fluorodeoxyglucose ( 18 F-FDG) PET/CT-derived parameters to differentiate soft tissue sarcoma (STS) and bone sarcoma (BS) from benign lesions. Methods Patients who had undergone pre-treatment 18 F-FDG PET/CT imaging and subsequent pathological diagnoses to confirm malignant (STS and BS, n = 37) and benign ( n = 33) soft tissue and bone lesions were retrospectively reviewed. The tumor size, PET and low-dose CT visual characteristics, maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and heterogeneous factor (HF) of each lesion were measured. Univariate and multivariate logistic regression analyses were conducted to determine the significant risk factors to distinguish sarcoma from benign lesions. To establish a regression model based on independent risk factors, and the receiver operating characteristic curves (ROCs) of individual parameters and their combination were plotted and compared. Conventional imaging scans were re-analyzed, and the diagnostic performance compared with the regression model. Results Univariate analysis results revealed that tumor size, SUVmax, MTV, TLG, and HF of 18 F-FDG PET/CT imaging in the STS and BS group were all higher than in the benign lesions group (all P values were < 0.01). The differences in the visual characteristics between the two groups were also all statistically significant ( P < 0.05). However, the multivariate regression model only included SUVmax and HF as independent risk factors, for which the odds ratios were 1.135 (95%CI: 1.026 ~ 1.256, P = 0.014) and 7.869 (95%CI: 2.119 ~ 29.230, P = 0.002), respectively. The regression model was constructed using the following expression: Logit ( P ) = − 2.461 + 0.127SUVmax + 2.063HF. The area under the ROC was 0.860, which was higher than SUVmax (0.744) and HF (0.790). The diagnostic performance of the regression model was superior to those of individual parameters and conventional imaging. Conclusion The regression model including SUVmax and HF based on 18 F-FDG PET/CT imaging may be useful for differentiating STS and BS from benign lesions.

Diagnostic value of 18F-FDG PET/CT in discriminating between benign and malignant lesions of the ribs

“…Additionally, Chen et al presented a regression model using SUVmax and a heterogeneity factor (calculated from a metabolism volume-threshold function from 40% to 80%) and found that it showed diagnostic performance superior to that of individual volumetric parameters. [ 19 ] Im et al reported that the MTV and TLG obtained using a liver-based threshold (liver SUVmean + 2 SDs) were the parameters with the most statistically significant predictive value for event-free survival (hazard ratios = 11.774 and 13.121, respectively, at posttherapy). [ 13 ] We evaluated the MTV and TLG using a liver-based threshold, which would be less influenced by the variability in SUV measurements caused by multiple PET/CT systems.…”

Characterization of focal hypermetabolic thyroid incidentaloma: An analysis with F-18 fluorodeoxyglucose positron emission tomography/computed tomography parameters

“…There are studies on TIs reporting that MTV, TLG, or both are useful parameters in distinguishing malignant lesions from benign ones[ 27 - 31 ], while other reported different conclusions[ 32 ]. The roles of MTV and TLG in other cancers are still open to debate[ 33 - 36 ]. In this study, both MTV and TLG were not useful in the discrimination.…”

Differential diagnosis of cardiac tumors: General consideration and echocardiographic approach

“…The best imaging technique in differentiating benign masses from their malignant counterpart (myxoma vs. myxosarcoma, fibroma vs. fibrosarcoma, angioma vs. angiosarcoma and so on) is PET/CT, which is based on the metabolic activity of the tissues: using 18‐Fluorodeoxiglucose ( 18 FDG), a high maximum standardized uptake (SUVmax) and intratumoral glucose metabolic heterogeneity factor (HF) may discriminate well between malignant (sarcomas, lymphomas, or other malignant tumors) and benign masses, as well as in differentiating a tumor thrombus from a simple thrombus. 105 , 106 , 107 , 108 , 109 , 110 To improve the sensitivity and specificity of 18 FDG in the particular setting of cardiac tumors, the physiologic glucose uptake by the myocardium must be minimized. This can be obtained with a low‐carbohydrate, high‐fat diet and with the administration of 50 Units/Kg of body weight of unfractioned heparin before the injection of 18 FDG.…”