1. Reversing "Flip-Flop" Phenomenon of 131 I and Glucose Avidity in RET-Fusion Positive Radioiodine-Refractory Thyroid Cancer Lesions After Treatment of Pralsetinib.
- Author
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Chan HP, Chen IF, Tsai FR, Kao CH, and Shen DH
- Subjects
- Male, Humans, Middle Aged, Thyroid Cancer, Papillary drug therapy, Fluorodeoxyglucose F18, Positron Emission Tomography Computed Tomography, Glucose, Proto-Oncogene Proteins c-ret, Iodine Radioisotopes therapeutic use, Thyroid Neoplasms pathology
- Abstract
Abstract: A 61-year-old man presented with papillary thyroid cancer in radioiodine-refractory status after high-activity 131 I treatments following thyroidectomy. FDG-avid neck and pulmonary metastases but without 131 I-uptake were detected. CCDC6-RET fusion was identified from the tumor lesion. He was treated with pralsetinib, a RET inhibitor, followed by another high-activity 131 I therapy. Posttherapeutic scan displayed restoration of 131 I avidity at those lesions only shown on previous FDG PET/CT. Reduced FDG avidity of those lesions and decreased serum antithyroglobulin antibody titer were also noticed. This case illustrated successfully reinduced 131 I avidity in papillary thyroid cancer through redifferentiation with target therapy to suppress tumor RET overexpression., Competing Interests: Conflicts of interest and sources of funding: The authors declare that they have no conflicts of interest. This work was supported in part by the following research grants: KSVGH21-CT12-19 from Kaohsiung Veterans General Hospital, Taiwan and VAC111-004 from Veterans Affairs Council, Taiwan., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2023
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