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 in soft tissue and bone lesions is essential for the prevention of excessive pathological biopsy and unplanned surgical resection. However, it remains a challenge and a standard diagnosis modality is urgently needed. The purpose of this study is to evaluate the usefulness of 18F- FDG PET/CT-derived parameters to differentiate soft tissue sarcoma (STS) and bone sarcoma (BS) from benign lesions.Methods: Patients who underwent pretreatment 18F-FDG PET/CT imaging and subsequent biopsy to confirm malignant (STS and BS, n=37) and benign (n=33) soft tissue and bone lesions were retrospectively reviewed. The tumor size, maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG) and heterogeneous factor (HF) of each lesion were measured. Univariate analysis and multivariate logistic regression analysis were performed to screen the significant risk factors to distinguish STS and BS from benign lesions. To establish a regression model based on independent risk factors, receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performances.Results: Univariate analysis results showed that tumor size, SUVmax, MTV, TLG and HF of 18F-FDG PET/CT imaging in STS and BS group were all higher than benign lesions group, the difference were statistically significant (all P value were<0.01). However, the multivariate regression model only included SUVmax and HF as independent risk factors, odds radios were 1.135(95%CI: 1.026~1.256, P =0.014), 7.869(95%CI: 2.119~29.230, P =0.002), respectively. The regression model was as follow: Logit (P) = -2.461+0.127SUVmax+2.063HF. The area under the ROC was 0.860 (95%CI: 0.771~0.948, P <0.001) higher than SUVmax 0.744(95%CI: 0.628~0.860, P <0.001) and HF 0.790 (95%CI:0.684~0.896, P <0.001).Conclusion: The regression model including SUVmax and HF based on 18F-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.…”

“…The volumetric parameters of 18 F-FDG PET/CT (e.g., MTV or TLG) have been introduced to overcome the limitations of the metabolic parameters of 18 F-FDG PET/CT (e.g., SUVmax or SUVpeak), and several studies have published diagnostic values for differentiating malignant from benign bone and soft tissue tumors. [18,19] These studies evaluated the diagnostic performance of the MTV and TLG using various threshold values with a fixed SUVmax of 2.0 or 2.5 or 40%, 50%, and 75% of SUVmax. Additionally, Chen et al presented a regression model using SUVmax and a heterogeneity factor (calculated from a metabolism volume-threshold function from 40% 80%) and found that it showed diagnostic performance superior to that of individual volumetric parameters.…”

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.…”

PET-CT in the Evaluation of Neoadjuvant/Adjuvant Treatment Response of Soft-tissue Sarcomas

“…There are weaknesses stemming from discordance between metabolic and volume-based PET-CT parameters. First, SUV max may not accurately reflect the malignant potential of STS and is not a precise indicator of global metabolic activity 51,57 . Because SUV max only reflects the most active part of a tumor, it may not be suitable for a more global assessment of an STS because these tumors show considerable spatial heterogeneity.…”