The prognostic and clinical significance of cervical stromal invasion in endometrial cancer: a multicenter retrospective study.

Abstract

Endometrial cancers that invade the cervical stroma are generally associated with worse clinical outcomes than tumors confined to the uterine corpus. However, tumors that spread to the cervical stroma often present other adverse prognostic features, making it uncertain whether cervical stromal invasion independently influences prognosis. Previous studies have provided limited and inconsistent results. The objective of this study was to evaluate the independent prognostic significance of cervical stromal invasion in patients with early-stage endometrial cancer. This multicenter retrospective study included patients with International Federation of Gynecology and Obstetrics 2009 stage I to II endometrial cancer who underwent surgical staging at 9 regional medical institutions across China between 2000 and 2019. The primary outcome was progression-free survival, and the secondary outcome was overall survival. Cox proportional hazards regression models were used to estimate hazard ratios and 95% confidence intervals for the association of cervical stromal invasion with survival outcomes. Propensity score matching was applied to balance baseline characteristics between patients with and without cervical stromal invasion. Variables used for propensity score were age at diagnosis, hypertension, diabetes, carbohydrate antigen 125 level, histological type, depth of myometrial invasion, lymphovascular space invasion, peritoneal cytology, surgical approach, type of hysterectomy, lymphadenectomy, and adjuvant therapy. To assess the robustness of the findings, subgroup analyses were performed. A total of 7383 patients were included (524 with cervical stromal invasion and 6859 without cervical stromal invasion). Cervical stromal invasion was not independently associated with decreased progression-free survival (adjusted hazard ratio, 1.31; 95% confidence interval, 0.94-1.81; P=.106) and overall survival (adjusted hazard ratio, 1.33; 95% confidence interval, 0.88-2.00; P=.171) at multivariable analysis performed on the entire cohort. In the propensity score-matched cohort, patients with and without cervical stromal invasion showed similar 5-year progression-free survival and overall survival (92.3% vs 93.7%, P=.493; 95.0% vs 95.7%, P=.791). Subgroup analyses by histological type and adjuvant therapy also showed no differences in survival outcomes between patients with and without cervical stromal invasion. After adjusting for confounders, the presence of cervical stromal invasion does not affect progression-free survival or overall survival in women with International Federation of Gynecology and Obstetrics 2009 stage I to II endometrial cancer.