| Autor: |
Parihar AS; Department of Nuclear Medicine, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, India., Mittal BR; Department of Nuclear Medicine, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, India., Kumar R; Department of Nuclear Medicine, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, India., Shukla J; Department of Nuclear Medicine, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, India., Bhattacharya A; Department of Nuclear Medicine, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, India. |
| Jazyk: |
angličtina |
| Zdroj: |
Thyroid : official journal of the American Thyroid Association [Thyroid] 2020 Apr; Vol. 30 (4), pp. 557-567. Date of Electronic Publication: 2020 Jan 23. |
| DOI: |
10.1089/thy.2019.0450 |
| Abstrakt: |
Background: Radioiodine therapy ( 131 I) forms a principal cornerstone in the management of differentiated thyroid cancer. Radioiodine-refractory differentiated thyroid cancer (RAIR-DTC) presents a challenge in detection of structural disease in patients with evidence of biochemical disease and in treatment of the disease using alternate therapies. The present study was conducted to compare the diagnostic accuracy (in terms of sensitivity and specificity) of 68 Ga-DOTA-RGD 2 positron emission tomography (PET)/computed tomography (CT) as a neoangiogenesis imaging modality with 18 F-FDG PET/CT, the current standard in diagnostic algorithm of RAIR-DTC, and to evaluate the radiotracer avidity on 68 Ga-DOTA-RGD 2 PET/CT for potential theranostics. Methods: Forty-four RAIR-DTC patients with negative post-therapy 131 I scan were prospectively enrolled. Serum thyroglobulin (sTg) and anti-thyroglobulin (ATg) measurements were performed with levothyroxine withdrawal (thyrotropin-stimulated state), and 18 F-FDG PET/CT and 68 Ga-DOTA-RGD 2 PET/CT studies were performed within 1 week of each other. Follow-up was performed with histopathology/sTg/ATg/conventional imaging. The findings of 18 F-FDG PET/CT and 68 Ga-DOTA-RGD 2 PET/CT were compared with the reference standard to obtain sensitivity, specificity, and overall accuracy. Degree of radiotracer uptake on 68 Ga-DOTA-RGD 2 PET/CT was described as tumor to background (T/B) and tumor to liver (T/L) ratios of standardized uptake value. Results: 68 Ga-DOTA-RGD 2 PET/CT detected a total of 123 lesions, with an overall sensitivity, specificity, and accuracy of 82.3%, 100%, and 86.4%, respectively. 18 F-FDG PET/CT detected a total of 144 lesions, with an overall sensitivity, specificity, and accuracy of 82.3%, 50%, and 75%, respectively. Most commonly identified disease sites were nodal metastases (82.9%), followed by thyroid bed lesions (10.5%). 82.1% of patients positive on 68 Ga-DOTA-RGD 2 PET/CT showed lesional radiotracer uptake higher than the liver (grade IV and grade V). Conclusions: 68 Ga-DOTA-RGD 2 PET/CT showed a similar sensitivity to, but higher specificity and overall accuracy than 18 F-FDG PET/CT in detection of lesions in RAIR-DTC patients. This novel application of the angiogenesis imaging modality can prove useful in RAIR-DTC, especially in patients with negative/suspicious 18 F-FDG PET/CT. Furthermore, since the majority of patients (82.1%) positive on 68 Ga-DOTA-RGD 2 PET/CT showed radiotracer avidity toward the higher end of the spectrum (grade IV and grade V), novel 177 Lu-based theranostics can be a potential treatment for these patients. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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