Objective To evaluate systematically the correlation between the expression level of human epididymis protein 4 (HE4) and lymph node metastasis of endometrial cancer (EC).

Methods Computers were used to search for the literatures about the correlation between the expression level of HE4 and lymph node metastasis of EC in PubMed, Cochrane, Web of Science, CBM, CNKI, and Wanfang Database. The search time was from the database establishment to May 2021. Articles were screened in accordance with the inclusion and exclusion criteria, and the quality of literature was evaluated by Newcastle Ottawa scale. Stata12.0 was used to perform meta-analysis, and TSA was used to evaluate the sample size.

Results A total of 2736 patients with EC were included in the 25 eligible studies. The results of meta-analysis showed that the expression level of HE4 in the EC-lymph-node metastasis group was significantly higher than that in the non-metastasis group (SMD=1.58, 95%CI: 1.13-2.03), and meta-regression analysis revealed that the results were related to the average age of patients in each study. TSA analysis exhibited that the total sample size of the included studies met the requirements.

Conclusion The expression level of HE4 is correlated with lymph node metastasis of EC, and this correlation may be affected by age, body mass index, and other factors. The correlation weakens with the increase in age.