Efficacy of postoperative thyroid-stimulating hormone inhibition therapy in differentiated thyroid cancer in China: a systematic literature review and meta-analysis.

Abstract

<h4>Background</h4>Thyroid-stimulating hormone (TSH) suppression therapy after surgery is recommended for patients with differentiated thyroid cancer (DTC) at risk of recurrence; however, evidence, including all stages of the disease, is inconclusive. A meta-analysis was conducted to assess the efficacy of postoperative treatment with or without TSH inhibition in Chinese patients who had undergone surgery for DTC.<h4>Methods</h4>PubMed (MEDLINE), Embase, and two Chinese databases (Wanfang and China National Knowledge Infrastructure) were searched for relevant studies published from inception to 1 April 2023. Study characteristics, patient characteristics, and recurrence or metastasis data were extracted. Data from 20 prospective studies were pooled for overall effect and for effects by tumor subtype using a random-effects model.<h4>Results</h4>Postoperative TSH suppression therapy significantly reduced recurrence risk <i>vs.</i> without at 1 year [risk ratio (RR): 0.24; 95% confidence interval (CI): 0.08-0.70], 3 years (RR: 0.21; 95% CI: 0.12-0.36), and 5 years (RR: 0.26; 95% CI: 0.17-0.41), and also reduced the risk of distant (RR: 0.17; 95% CI: 0.08-0.37) and central (RR: 0.18; 95% CI: 0.09-0.36) lymph node metastasis at 3 years. An additional analysis, including two retrospective studies, found a significant reduction of risk at 5 years for distant (RR: 0.24; 95% CI: 0.14-0.42) and central (RR: 0.21; 95% CI: 0.12-0.35) lymph node metastasis.<h4>Conclusions</h4>This meta-analysis showed that TSH suppression therapy was effective in reducing the risk of recurrence and metastasis <i>vs.</i> no TSH suppression therapy. Follow-up studies are required to determine long-term safety risks.