Thyroid incidentalomas in PSMA PET/CT: a systematic review and meta-analysis

Purpose Thyroid incidentaloma is an abnormal finding detected by imaging exams and which was not the initial reason for performing it. This article aimed to verify the prevalence of TI in PSMA PET/CT and to analyze its risk of malignancy through a systematic review and meta-analysis. Methods A systematic search through electronic databases was conducted until April 2022 to identify relevant articles on thyroid findings in PSMA PET/CT. Observational studies that reported TI detected with PSMA PET/CT were eligible for inclusion. Results Three hundred and eighty-four abstracts were reviewed in electronic databases and bibliographic references, including 5 studies containing 8422 patients for qualitative and quantitative analysis. PSMA PET/CT identified 96 TI (1.3%), of which 6 were malignant. Only three studies describe TI uptake pattern. The prevalence of TI with a focal pattern was 67.6% (95% CI 57.2–77.2%; I 2 = 0%), while the risk of malignancy in focal lesions alone was 9.0% (95% CI 3.0–17.7%; I 2 = 0.0%). Conclusion TI is rarely detected on PSMA PET/CT, and the risk of malignancy can reach considerable values in lesions with a focal pattern. Therefore, follow-up and appropriate clinical investigation of lesions with focal PSMA uptake in the thyroid are important.