Clinical significance of matrix metalloproteinase-9 expression in papillary thyroid carcinoma: a meta-analysis.

OBJECTIVE: The purpose of this study was to investigate the relationship between the expression of matrix metalloproteinase-9 (MMP-9) and pathological indexes in papillary thyroid carcinoma (PTC). EVIDENCE OBTAINED: The database was searched in PubMed, Embase, CNKI, and Web of Science databases for relevant clinical trials. The odds ratio (OR) and 95% confidence interval (CI) show the effect of MMP-9 expression and age, tumour size, gender, lymph node metastasis (LNM), and TNM (tumour, lymph node, metastasis) stage. Statistical analysis of the data was performed using Stata 17.0. EVIDENCE SYNTHESIS: A total of 1433 patients with PTC were included in this meta-analysis. MMP-9 expression was significantly correlated with LNM (OR = 3.92, 95% CI = 2.71-5.65, P = 0.000), tumour size (OR = 1.69, 95% CI = 1.13-2.52, P = 0.011), and TNM stage (OR = 2.95, 95% CI = 2.10-4.13, P = 0.000), but not with gender (OR = 0.90, 95% CI = 0.66-1.22, P = 0.487) and age (OR = 1.36, 95% CI = 0.93-1.98, P = 0.115). CONCLUSIONS: Our meta-analysis showed that MMP-9 was significantly associated with LNM, tumour size, and TNM stage; therefore, MMP-9 may be a reliable prognostic biomarker for patients with PTC. However, more high-quality studies are needed to support these findings further.