Work

A prospective, exploratory study of 18F-PSMA-1007 PET/CT in patients with medullary thyroid cancer

Year: 2026

Type: article

Abstract: Prostate specific membrane antigen (PSMA) is expressed in the neo-vasculature of most medullary thyroid carcinomas (MTCs) and can be imaged with PET/CT. This prospective, feasibility study evaluated the diagnostic performance of 18 F-PSMA-1007 PET/CT in MTC patients compared to 18 F-FDG PET/CT. Eligible patients were ≥ 1 18 years, had histopathologically confirmed MTC, elevated calcitonin/CEA, and a clinically indicated 18 F-FDG PET/CT. All imaging ≤ 1 year prior was reviewed to establish a composite reference standard (CRS) of total tumor lesions. Analyses were performed at patient, region (neck/thorax/abdomen/bone), and lesion level. Lesions were also semi-quantified using SUVpeak. In eight included patients, the CRS identified 186 tumor lesions. Patient-based sensitivity of 18 F-PSMA-1007 PET/CT was 88% (median lesion per patient 3, range 2 – 51), while 100% for 18 F-FDG PET/CT (lesions per patient 5, range 2 – 45). Of 32 evaluated regions, 16 (50%) were tumor positive, of which 18 F-PSMA-1007 PET/CT and 18 F-FDG PET/CT identified 12 (sensitivity 75%), and 14 (sensitivity 88%) correctly, respectively. 18 F-PSMA-1007 PET/CT detected 84 lesions (sensitivity 45%) while the 18 F-FDG PET/CT detected 85 (sensitivity 46%) of 186 tumor lesions (p = 0.893). Lesion-based semi-quantitative analysis identified a higher SUVpeak on 18 F-PSMA-1007 ( 18 F-PSMA-1007 3.37 (range 1.78 – 9.63) vs 18 F-FDG PET/CT 2.52 (range 1.04 – 5.51) p < 0.001). In this exploratory, hypothesis-generating study, 18 F-PSMA-1007 PET/CT shows modest utility in assessing disease extent in MTC patients. Its value in staging therefore seems limited when compared to existing imaging modalities. Nonetheless, high tracer uptake (exceeding the liver) in selected lesions might identify possible candidates for 177 Lu-PSMA-617 therapy, warranting further research.

Source: European Journal of Nuclear Medicine and Molecular Imaging

DOI: 10.1007/s00259-026-07902-6

Authors: Eline C. Jager, Schelto Kruijff, Reina W. Kloet, Thera P. Links, Adrienne H. Brouwers

Institutions: University Medical Center Groningen, University of Groningen, Karolinska Institutet

Language: English

Topic: Thyroid Cancer Diagnosis and Treatment

Subfield: Endocrinology, Diabetes and Metabolism

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,490