Increasing the yield of recombinant thyroid-stimulating hormone-stimulated 2-(18-fluoride)-flu-2-deoxy-D-glucose positron emission tomography-CT in patients with differentiated thyroid carcinoma

Abstract

Objective: The aim of this study was to assess the accuracy of recombinant thyroidstimulating hormone (rTSH)-stimulated 2-(18-fluoride)-flu-2-deoxy-D-glucose ( Results: 58 rTSH PET-CT scans were performed in 47 patients with a previous thyroidectomy and radioiodine ablation. The only indication for PET-CT was a raised thyroglobulin level in 46 of 58 scans, with the remainder for characterisation of equivocal radiology or staging. 25 (43%) of PET-CT scans were positive for recurrent disease. Histological correlation was available for 21 (36%) scans. The overall sensitivity, specificity, positive predictive value and negative predictive value were 69%, 76%, 72% and 73%, respectively. Median unstimulated thyroglobulin in true-positive scans was 33 mg l 21 and 2.2 mg l 21 in the remainder (p50.12). 4 of 35 (11%) patients with unstimulated thyroglobulin levels ,10 mg l 21 had true-positive scans. Median stimulated thyroglobulin in true-positive scans was 320 mg l 21, and 10 mg l 21 in the remainder (p50.046), with no positive scans with a stimulated thyroglobulin ,8 mg l 21. PET-CT directly influenced patient management in 17/58 (29%) scans. Conclusion: rTSH PET-CT is a useful imaging technique for detecting disease recurrence in patients with iodine-resistant differentiated thyroid cancer. Low stimulated thyroglobulin levels are potentially useful in identifying patients unlikely to benefit from a PET-CT scan.

F18-FDG-PET for recurrent differentiated thyroid cancer: a systematic meta-analysis

“…The literature search identified 34 studies with a total of 2639 patients meeting the inclusion criteria ( 6 , 16 – 48 ). Eleven studies reported on the diagnostic accuracy of single-modality PET, 17 on PET/CT, and six on both PET and PET/CT (“mixed”).…”

Usefulness of PET/CT with 18F-FDG in Patients with Differentiated Thyroid Carcinoma after Radioiodine Therapy: An Italian Multicenter Study

“…Whether or not PET/CT with 18 F-FDG in DTC should be performed under TSH stimulation remains a controversial issue. In our retrospective analysis, we included only patients who underwent PET/CT under TSH stimulation, as it has been reported that TSH stimulation not only influences PET/CT's sensitivity, but also significantly affects its impact on clinical management [22,23].…”

Usefulness of PET‐CT scan in recurrent thyroid cancer

“…19,20 However, a lower sensitivity in the diagnostic accuracy of 18F-FDG-PET/PET-CT imaging after rhTSH stimulation was observed in the suspected recurrent thyroid cancer patients with low titer of thyroglobulin. 20 In this set of patients, the utility of rhTSH stimulation procedure could lie in the identification of patients with low stimulated Tg serum levels: consequently, the assessment of Tg serum level after rhTSH stimulation is potentially useful in identifying patients unlikely to benefit from an 18 F-FDG-PET-CT. 21 Finally, there are other interesting points that emerge from analyzed literature. First, a previously good quality conventional imaging raised the sensitivity in the detection of recurrent thyroid cancer of 18 F-FDG-PET-CT. Second, a direct correlation between SUV (standardized uptake value) max and cervical lymph-nodes size was observed.…”

“…In this set of patients, the utility of rhTSH stimulation procedure could lie in the identification of patients with low stimulated Tg serum levels: consequently, the assessment of Tg serum level after rhTSH stimulation is potentially useful in identifying patients unlikely to benefit from an 18 F-FDG-PET-CT. 21 …”