An analysis of the significance of the lymph node ratio and extracapsular involvement in the prognosis of endometrial cancer patients

Introduction
The primary aim of our study was to analyse the impact of the lymph node ratio (LNR) and extracapsular involvement (ECI) on the prognosis of endometrial cancer (EC) patients.

Material and methods
We carried out a retrospective analysis of 886 patients surgically treated for EC between 2000 and 2015. In the subgroup of patients with lymph node metastases (LNM), we evaluated the impact of the number and localization of the LNM, LNR, and ECI on patients’ overall survival (OS).

Results
In the group of patients with LNM, 0.3 was the optimal LNR cut-off for differentiating between short- and long-term survivors [HR = 2.94 (95% CI: 1.49–5.80)]. Patients with a LNR ≥ 0.3 had a significantly shorter OS period (35.0 months, range 0.2–175 months) compared to patients with a LNR < 0.3 [median OS – mOS, was 143, range 15–169 months; (p = 0.003]. We observed significant differences in the mOS of EC patients without LNM compared to patients with LNM, as well as those with both LNM and ECI (p < 0.0001). In the group of patients with LNM, we also found that a poorer prognosis depended on the extension of the primary tumour.

Conclusions
Our results suggest that when LNM are found, the long-term outcomes of EC patients are worse in those who have a LNR ≥ 0.3, the presence of ECI, and a more advanced extension of the primary tumour.