Recombinant human thyrotropin versus thyroid hormone withdrawal in radioiodine remnant ablation for differentiated thyroid cancer: a meta-analysis.

AIM: We aim to assess the effects of recombinant human thyrotropin (rhTSH) versus thyroid hormone withdrawal (THW), and rhTSH-aided low doses (1.11 GBq and 1.85 GBq) versus high dose (3.7 GBq) of radioiodine in the residual ablation for differentiated thyroid cancer (DTC).

METHODS: Studies were obtained from computerized searches of MEDLINE, EMBASE, the Cochrane Library (all until September 2012). Randomized controlled trials were included.

RESULTS: Altogether 1325 patients with DTC participated in seven trials for residual ablation. Overall, studies had a low risk of bias. We found no statistically significant differences between rhTSH and THW treatment in terms of successful ablation rate (OR 0.87, 95% CI 0.56 to 1.37, P=0.56) but significant benefits in health-related quality of life (mean difference 3.59, 95% CI 2.81 to 4.37, P<0.00001), adverse events during and after ablation (OR 0.57, 95% CI 0.44 to 0.73, P<0.00001), radiation exposure to blood and bone marrow (mean difference -0.01, 95% CI -0.02 to -0.01, P<0.00001). In addition, no significant difference was found in the successful ablation rate between the low dose (1.11 GBq and 1.85 GBq) and high dose (3.7 GBq) of radioiodine aided by rhTSH (OR 0.85, 95% CI 0.49 to 1.47, P=0.56). There were no deaths and no serious adverse effects in DTC patients treated with either rhTSH or THW, maximum follow-up was 12 months. None of the included trials investigated secondary malignancies or economic outcomes.

CONCLUSION: rhTSH is as effective as THW on radioiodine thyroid remnant ablation with significant benefits on health-related quality of life, adverse effects during and after ablation, decreased whole body radiation exposure. The lower radioiodine doses are as effective as high doses for remnant ablation under rhTSH stimulation.