Sama Alsofi, Therese Ovesen, Kasper Drimer Berg, Ali Abood, Ditte Hermansen
Focal PSMA-PET/CT-positive thyroid incidentalomas are uncommon and associated with a low risk of clinically relevant malignancy. A less aggressive diagnostic approach, therefore, appears justified.
INTRODUCTION: With the widespread use of prostate-specific membrane antigen (PSMA)-PET/CT in prostate cancer management, incidental thyroid findings are occasionally detected. However, the malignancy risk associated with focal PSMA-PET/CT-positive thyroid incidentalomas remains unclear, and most patients are therefore referred to a fast-track cancer pathway. This study aimed to determine the incidence and malignancy risk of focal PSMA-PET/CT-positive thyroid incidentalomas and to assess whether routine fast-track referral is justified.
METHODS: In this retrospective cohort study, all PSMA-PET/CTs performed between January 2019 and December 2023 were reviewed. Patients with focal thyroid PSMA uptake were included. Medical records were examined to collect data on imaging and subsequent evaluation at an ear, nose and throat department, including ultrasonography, thyroid function tests, cytology, histopathology and follow-up. The malignancy risk was determined based on cytological and histopathological findings as well as clinical follow-up.
RESULTS: Among 1,477 PSMA-PET/CTs, thyroid uptake was identified in 80 (5.4%), of which 42 (2.8%) were focal. Forty patients with focal uptake were included in the study. Malignancy was confirmed in one patient, corresponding to an overall malignancy rate of 2.5%. Histopathology revealed papillary thyroid carcinoma.
CONCLUSIONS: Focal PSMA-PET/CT-positive thyroid incidentalomas are uncommon and associated with a low risk of clinically relevant malignancy. A less aggressive diagnostic approach, therefore, appears justified.
FUNDING: None.
TRIAL REGISTRATION: Not relevant.