Clinical value of baseline 18F-FDG PET/CT in soft tissue sarcomas

Abstract

Background The use of 18F-FDG Positron emission tomography/Computed tomography (PET/CT) in the initial staging of many cancers is clearly established. Most soft tissue sarcoma (STS) has a high affinity for 18F-FDG, which is why 18F-FDG PET/CT has been proposed as a non-invasive method, useful in diagnosis and follow-up. The standardized uptake value values (SUV), the volume-based metabolic parameters MTV (metabolic tumor volume), and TLG (total lesion glycolysis) determine tumor viability and provide its total volume and the total activity of metabolically active tumor cells. The histological grade is the most important predictor of metastases and mortality associated with STS, and a significant relationship between the metabolic parameters of 18F-FDG PET/CT and the histological grade has been described. Methods A retrospective study was conducted on STS patients, who had histological grade according to the FNCLCC (Fédération Nationale des Centres de Lutte Contre Le Cancer) criteria, as well as a baseline PET/CT. SUV (SUVmax, SUVmean, and SUVpeak), MTV, and TLG were quantified. A T-student test was performed to establish the relationship between the metabolic biomarkers and the histological grade. Their usefulness as predictors of the histological grade was verified using receiver operator characteristic (ROC) curves. A survival function study was performed using the Kaplan–Meier method. To assess the prognostic utility of the metabolic biomarkers we use the Log-Rank method. Results The SUV values were useful to discriminate high-grade STS. We found a significant relationship between the histological grade and the SUV values. SUVmax, SUVpeak, MTV, and TLG were predictors of overall survival (OS). There were no significant differences in the OS for the SUVmean, or in the disease-free survival (DFS) for SUVmax, SUVmean, SUVpeak, MTV, and TLG. Conclusions The SUVmax, SUVmean, and SUVpeak values correlate with the HG and are useful to discriminate high-grade from low-grade STS. Patients with high SUVmax, SUVpeak, MTV, and TLG have a significantly lower OS.

Comparing Apparent Diffusion Coefficient and FNCLCC Grading to Improve Pretreatment Grading of Soft Tissue Sarcoma—A Translational Feasibility Study on Fusion Imaging

“…Several studies have recently demonstrated significant results for grading differentiation based on the standardized uptake value (SUV). Additionally, a correlation between the mitotic count or tumor necrosis and the SUV could be demonstrated here [ 20 , 23 , 24 ].…”

“…In particular, functional imaging may be suitable to describe tumor aggressiveness by estimating surrogate metabolism markers, blood flow, and tumor cellularity. Cohort studies have described MRI, CT, and positron emission tomography (PET)-CT as applicable modalities for this purpose [ 18 , 19 , 20 ].…”

Incidental Detection of a Rare Pediatric High-Grade Fibrosarcoma in a Post-traumatic Setting: The Conundrum of Intra-Abdominal Hematoma versus Neoplasia

“…The role of FDG-PET/CT in diagnosis of soft tissue sarcomas is not well established as there remain challenges in differentiating malignant from benign lesions [ 21 ]. However, due to the sensitivity to tumors with high metabolic activity, such as high-grade sarcomas, as found in our case, FDG-PET/CT improves the likelihood of detecting small regional deposits or distant metastatic disease in the initial workup period and plays an important role in identifying or excluding local relapse or metastasis essential in the long-term management of these patients [ 22 , 23 ].…”

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

“…In addition, it is stable, repeatable, and thus the most commonly reported parameter. In comparison, SUV mean is the average SUV within a ROI and incorporates information from multiple voxels 8 ; thus, it is less sensitive to image noise and scan time than SUV max , especially in small tumors 9 . The metabolic tumor volume (MTV) and total lesion glycolysis (TLG) are volumetric metabolic parameters that can compensate for the limitations of SUV max because they reflect the glucose metabolism in the entire tumor volume 10 .…”