Association between preoperative serum TSH and tumor status in patients with papillary thyroid microcarcinoma.

Thyroid-stimulating hormone (TSH) is a growth factor affecting the initiation or progression of papillary thyroid cancer (PTC). However, the relationship between preoperative serum TSH and papillary thyroid microcarcinoma (PTMC) remains controversial. To investigate the relationship between preoperative serum TSH and tumor status of PTMC, a multicentered retrospective study was performed from January 2014 to December 2016. The cohort of this study consisted of 1997 patients who underwent thyroid surgery. Serum TSH concentrations were measured and PTMC was diagnosed based on the post-operation pathological report. Results showed that the preoperative serum TSH concentration was not related to age and gender but was positively associated with tumor size. Furthermore, higher TSH level was associated with extra-thyroidal extension and lymph node metastasis (LNM). These results indicated that TSH might not be involved in the development of PTMC but may be associated with PTMC progression. Preoperative serum TSH concentration should be considered as risk predictor for tumor progression in patients with PTMC.