[¹⁸F]FDG-PET/CT texture analysis in thyroid incidentalomas: preliminary results

Area of Science:

• Nuclear medicine imaging
• Radiomics
• Oncology

Background:

• The clinical significance of incidental thyroid 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) uptake on positron emission tomography/computed tomography (PET/CT) scans is debated.
• Thyroid incidentalomas detected on PET/CT require accurate diagnosis to guide management.

Purpose of the Study:

• To assess the efficacy of [18F]FDG-PET/CT texture analysis in predicting the final diagnosis of thyroid incidentalomas.
• To determine if texture analysis can differentiate between benign and malignant thyroid nodules found incidentally on PET/CT scans.

Main Methods:

• Retrospective analysis of 50 patients with thyroid incidentalomas and available fine needle aspiration (FNA) or histological data.
• Segmentation of PET images using 40% SUVmax threshold and texture analysis performed with LifeX software.
• Statistical analysis to compare texture features between benign and malignant nodules, including ROC analysis for predictor identification.

Main Results:

• Of 50 patients, 32 had benign nodules and 18 had malignant nodules (15 primary thyroid cancers, 3 metastases).
• Significant differences were observed in SUVmax (p=0.01) and skewness (p=0.02) between benign and malignant nodules.
• Skewness demonstrated the best area under the curve (0.66) among tested textural features, while SUV-based parameters offered higher specificity and MTV, TLG, skewness, kurtosis, and correlation_GLCM offered better sensitivity.

Conclusions:

• [18F]FDG-PET/CT texture analysis shows promise in stratifying patients with thyroid incidentalomas based on malignancy risk.
• This technique could potentially refine the selection of patients who need to undergo cytology for suspected malignant thyroid nodules.