Related Experiment Video
Updated: Feb 26, 2026
A Swin Transformer-Based Model for Thyroid Nodule Detection in Ultrasound Images
Published on: April 21, 2023
Evaluation of [68Ga]Ga-FAPI PET/CT-derived parameters in thyroid nodules with emphasis on indeterminate cytology
Merve Okuyan1, Umut Elboga2, Mehmet Bastemir3
1Department of Nuclear Medicine, Recep Tayyip Erdogan University Training and Research Hospital, Rize, 53000, Turkey.
Objectives:
To evaluate the diagnostic performance of [68Ga]Ga-FAPI PET/CT-derived metabolic parameters in thyroid nodules and their association with cytological risk stratification, with particular emphasis on indeterminate nodules.
Methods:
Forty patients with 53 thyroid nodules who underwent [68Ga]Ga-FAPI PET/CT were prospectively analysed. Maximum standardized uptake value (SUVmax) and tumour-to-background ratio (TBR) were calculated for each nodule. Ultrasound-based malignancy classification (USG-BM) and Bethesda cytology categories were recorded. Comparisons between benign and malignant nodules were performed in the overall cohort (Bethesda I-VI) and within the Bethesda III-IV subgroup. Multivariable logistic regression was used to identify independent predictors of malignancy. Diagnostic performance was assessed using receiver operating characteristic analysis.
Results:
In the overall cohort, SUVmax and TBR were significantly higher in malignant nodules than in benign nodules (P < .01). In multivariable analysis, TBR showed a stronger independent association with malignancy, whereas USG-BM was not independently predictive. Within the Bethesda III-IV subgroup, SUVmax and TBR did not differ significantly in univariable analyses; however, TBR demonstrated a borderline independent association with malignancy in multivariable analysis (P = .058). Maximum standardized uptake value and TBR values were significantly higher in Bethesda V-VI nodules compared with Bethesda III-IV nodules (both P < .001). Receiver operating characteristic (ROC) analysis demonstrated good discriminative performance for both parameters, with TBR yielding a higher area under the curve and high negative predictive values.
Conclusion:
[68Ga]Ga-FAPI PET/CT-derived metabolic parameters, particularly TBR, show promising diagnostic performance for thyroid nodule characterization. High negative predictive values suggest a potential complementary role for excluding malignancy, especially in indeterminate nodules. Further multicentre studies are warranted.
Advances In Knowledge:
[68Ga]Ga-FAPI PET/CT-derived metabolic parameters were higher in malignant thyroid nodules compared with benign lesions. These findings suggest that FAPI PET/CT may provide complementary functional information in nodules with indeterminate cytology.
