Multimodal Characterization of a PSMA-Positive Thyroid Nodule Using 68Ga-PSMA and 124Iodine PET/US Fusion Imaging

A 54-year-old male diagnosed with prostate cancer was referred for 68Gallium-PSMA-11 PET/CT. The scan revealed a solitary PSMA-positive thyroid lesion. On PET/ultrasound fusion imaging, a nodule with moderate risk of malignancy (TIRADS 4B) could be unambiguously correlated. Additional 124Iodine PET/ultrasound fusion imaging revealed normal iodine uptake within the PSMA-positive thyroid nodule. Fine-needle aspiration cytology was performed using an ultrasound needle-guidance system. The cytopathological investigation confirmed a benign thyroid nodule and excluded a thyroid carcinoma as well as a prostate cancer metastasis. Immunohistochemistry was positive for thyroglobulin staining.

[1]  I. V. D. van der Ploeg,et al.  Retrospective analysis of PSMA PET/CT thyroid incidental uptake in adults: incidence, diagnosis, and treatment/outcome in a tertiary cancer referral center and University Medical Center , 2022, European Journal of Nuclear Medicine and Molecular Imaging.

[2]  J. Buatti,et al.  Prostate-Specific Membrane Antigen (PSMA) Theranostics for Treatment of Oligometastatic Prostate Cancer , 2021, International journal of molecular sciences.

[3]  M. Freesmeyer,et al.  De Quervain Subacute Thyroiditis With Moderate PSMA Uptake Mimicking Thyroid Metastasis of Renal Cell Carcinoma. , 2021, Clinical Nuclear Medicine.

[4]  B. de Keizer,et al.  Retrospective Analysis of PSMA PET/CT Thyroid Incidental Uptake in Adults: Incidence, Diagnosis and Treatment/outcome in a Tertiary Cancer Referral Center and an Academic Hospital , 2021 .

[5]  P. Seifert,et al.  The FUSION iENA Study: Comparison of I-124-PET/US Fusion Imaging with Conventional Diagnostics for the Functional Assessment of Thyroid Nodules by Multiple Observers , 2019, Nuklearmedizin.

[6]  P. Seifert,et al.  Standard Needle Magnetization for Ultrasound Needle Guidance: First Clinical Experiences in Fine‐Needle Aspiration Cytology of Thyroid Nodules , 2019, Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine.

[7]  P. Seifert,et al.  I-124-PET/US Fusion Imaging in Comparison to Conventional Diagnostics and Tc-99m Pertechnetate SPECT/US Fusion Imaging for the Function Assessment of Thyroid Nodules. , 2019, Ultrasound in medicine & biology.

[8]  S. Ben-Haim,et al.  68Ga-PSMA PET/CT in prostate cancer patients – patterns of disease, benign findings and pitfalls , 2018, Cancer Imaging.

[9]  T. Winkens,et al.  Low-activity (124)I-PET/low-dose CT versus (131)I probe measurements in pretherapy assessment of radioiodine uptake in benign thyroid diseases. , 2014, The Journal of clinical endocrinology and metabolism.

[10]  Jin Young Kwak,et al.  Thyroid imaging reporting and data system for US features of nodules: a step in establishing better stratification of cancer risk. , 2011, Radiology.

[11]  Dharmendra Kumar,et al.  The Bethesda System for Reporting Thyroid Cytopathology , 2014 .

[12]  The Bethesda System for Reporting Thyroid Cytopathology: Definitions, Criteria, and Explanatory Notes , 2023 .