Abstract 552P
Background
The impact of lymph-vascular space invasion (LVSI) on the prognosis of endometrial cancer (EC) patients remains controversial and lacks support from large sample size studies. Very few have examined whether LVSI is related to prognosis of non-endometrioid cancer patients. Our goal was to determine the impact of LVSI on the clinical prognosis of patients with endometrioid and non-endometrioid cancer respectively.
Methods
This multicenter retrospective cohort study used the Chinese Endometrial Carcinoma Consortium database to identify 3715 women with endometrioid and non-endometrioid cancer who underwent initial surgical treatment between January 1, 2010 and December 31, 2019 and without other malignancies. The median (interquartile range) duration of follow-up was 39 (22-63) months. Patients were stratified based on histopathologic types and LVSI status. A propensity score matching (PSM) algorithm was used to balance the clinical characteristics (ratio 1:1). The impact of LVSI on the prognosis was examined using Kaplan-Meier analysis. univariate and multivariate Cox proportional hazards regression analyses were performed to identify independent high-risk factors of DFS and OS. The end points were disease-free survival (DFS) and overall survival (OS) and were assessed in the endometrioid and non-endometrioid cancer population.
Results
Among the 3715 women, LVSI was found in 346 (9.31%) cases. In the after PSM cohorts, LVSI significantly decreased the DFS (P=0.005), but not OS (P=0.66) of endometrioid cancer patients. For patients with non-endometrioid cancer, there was no statistical difference in DFS (P=0.54) or OS (P=0.51). In multivariate Cox proportional hazards regression, LVSI was an independent risk factor of DFS (hazard ratio [HR], 2.62 [95% CI, 1.35-5.10]; P=0.005) and not OS (HR, 1.24 [95% CI, 0.49-3.13]; P=0.66) for endometrioid cancer patients. LVSI was not a prognostic factor of neither DFS (HR, 1.28 [95% CI, 0.58-2.81]; P=0.54) or OS (HR, 1.33 [95% CI, 0.55-3.13]; P=0.52) for non-endometrioid cancer patients.
Conclusions
The presence of LVSI was associated with decreased DFS of endometrioid cancer patients, and had no influence on the prognosis of non-endometrioid cancer patients.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
This work was supported by the Taishan Scholar Youth Project of Shandong Province (grant number tsqn201812130)，and the Research Leader Studio of Jinan (grant number 2019GXRC049).
Disclosure
All authors have declared no conflicts of interest.