Akademik Veri Yönetim Sistemi
Annual Congress of the European Association of Nuclear Medicine, Vienna, Avusturya, 21 - 25 Ekim 2017, cilt.44, ss.153, (Özet Bildiri)
Purpose
In patients with elevated parathyroid hormone(PTH) levels, conventional imaging modalities including ultrasonography(USG) and parathyroid scintigraphy with Tc-99m MIBI(MIBI) are used for detection of suspected parathyroid adenomas. However, both modalities could be negative despite persistent hyperparathyroidism. F-18 Choline(FCH) PET has recently been suggested to be a better alternative for detection of parathyroid adenomas. The aim of our study is to compare the diagnostic accuracy of FCH-PET with conventional imaging modalities for detection of parathyroid adenomas.
Subjects and Methods
Among 130 adult patients with primary or secondary hyperparathyroidism that have been prospectively enrolled in our on-going study, 93 patients with postoperative histopathological confirmation or follow-up biochemical results were included in our comparison. FCH-PET/CT, MIBI dual-phase imaging and USG were performed to all patients. Mean 8,8±2,4 mCi(325±88,8 MBq) FCH was applied iv and dual-time PET/CT imaging was performed 15min and 45min after FCH administration. Gold standard was postoperative histopathology in patients that have undergone parathyroidectomy operation, and follow-up serum PTH, calcium, phosphate and vitamin-D levels in patients with negative imaging results.
Results
Total 61 patients underwent surgery, resulting in parathyroid adenoma in 54, neoplasia in 3 and hyperplasia in 3 patients. In one patient parathyroid tissue was not found in the pathology specimen. FCH-PET could successfully localize 95,1% of the hyperfunctioning parathyroid glands among operated patients. It was false negative(FN) in 3,3% and false positive(FP) in 1,6% of patients. Sensitivity and positive predictive value(PPV) of FCH-PET are 96,7% and 98,3%, respectively. MIBI could detect only 48,3% of the lesions and missed 50%. USG was positive in 50% of the lesions and missed 48,1%. Sensitivity of MIBI and USG remained 49,2% and 51,0%, respectively. Total 32 patients were followed without surgery and PTH levels decreased in 9 patients, remaining high in 23 patients. FCH was positive in 52,2%(12/23) of patients with persistent hyperparathyroidemia, whereas MIBI and USG was positive in 17,4%(4/23) and 8,7%(2/23), respectively. Out of 30 patients, that were negative with both MIBI and USG, 15 were FCH positive and adenoma was confirmed with histopathology in 10 patients, whereas PTH level remained high in 5 patients, who could not be operated.
Conclusion
FCH-PET is an effective imaging tool with higher sensitivity compared to conventional imaging modalities for detection of hyperfunctioning parathyroid glands. It should be used especially in cases with persistent hyperparathyroidism despite negative MIBI and USG results.
Acknowledgements: This work was supported by Istanbul University Scientific Research Projects (project-no:24412).