In general, thyroglobulin (Tg) and a radioactive scan correlate well with each other in follow-up studies for differentiated thyroid carcinoma after thyroid remnant ablation. To maximise radioiodine uptake in malignant thyroid cells, it is necessary to elevate TSH cells by the withdrawal of thyroid hormone therapy or, more recently to use recombinant human TSH. However, whether PET scanning for the detection of Tg-positive and scan –negative metastases for DTC should be performed under TSH stimulation remains controversial.

Ma et al. searched the MEDLINE, EMBASE and Cochrane library for prospective controlled trials using TSH stimulation as an intervention. A meta-analysis was carried out using the Review Manager software. Seven prospective controlled studies with 168 patients were found. PET scans taken under TSH stimulation altered clinical management in 9% of patients in 5 paired studies.

The data analysis undertaken by the authors indicates that TSH stimulation should be recommended for DTC patients undergoing PET scanning. Ma et al. (2010), European Journal of Endocrinology, in press (published online on 19 May 2010).

Read the full article at DOI: 10.1530/EJE-10-0256.