Association of endometrial polyps with STC-1 and STC-2 in infertile patients

Abstract

Objective: The present study aimed to evaluate the impact of endometrial polyps (EPs) on the endometrium of patients with unexplained infertility using stanniocalcin-1 and -2 proteins (STC), whose effects on endometrial receptivity have been reported recently.

Materials and methods: A case-control study was performed, consisting of 26 patients who underwent endometrial sampling for diagnosis and/or treatment and diagnosed with EP on biopsy and/or excision material, and 23 patients with normal endometrial findings in the pathology, for a total of 49 patients with unexplained infertility. An immunohistochemistry examination was performed on paraffin-embedded tissue samples from both groups to understand whether there was a relationship between EP and STC. Staining results of the polyp and control groups for STC-1 and STC-2 were compared, and it was investigated whether STCs were predictive for EP.

Results: In the comparison performed between the H-score evaluation results of the control and polyp groups after the immunohistochemical staining method, the staining in the polyp group was significantly higher for both STC-1 (p < 0.001) and STC-2 (p < 0.001). There was more staining with STC-1 than STC-2 in all groups (STC-1: 15.08; STC-2: 8.27; p < 0.05). In the logistic regression analysis established with STC-1, STC-2, and age, the predictive effect of STC-1 for EP was statistically significant (p = 0.040; odds ratio: 1.66; 95% confidence interval: 1.02-2.68). In EP, according to receiver operating characteristic curve analysis, area under the curve was 0.980 (likelihood ratio: 20.35; p < 0.05), and the cut-off value was 18 for STC-1.

Conclusion: In infertile patients, since STC-1, which affects endometrial receptivity, is found to be significantly higher in polyps and has a predictive effect on polyps, in patients with unexplained infertility, routine uterine cavity evaluation and routine excision of polypoid lesions detected during this period may have a positive effect on endometrial receptivity.