A low-risk group for lymph node metastasis is accurately identified by Korean gynecologic oncology group criteria in two Japanese cohorts with endometrial cancer

Abstract

Objective: The Korean Gynecologic Oncology Group (KGOG) recently proposed new pre-operative criteria to identify a low-risk group for lymph node metastasis in endometrial cancer. The aim of this study was to test whether the good performance of the criteria can be reproducible in diverse clinical settings.

Methods: From two Japanese hospitals, 319 patients with endometrial cancer who underwent systemic lymphadenectomy were retrospectively reviewed. In one hospital, para-aortic lymphadenectomy was routinely performed, but it was selectively performed in the other hospital. The performance of the criteria was determined by adjusting the false-negative rate (FNR) at the given prevalence of nodal metastasis of 10% using Bayes' theorem.

Results: Nodal metastasis rate of the study population was 12.9%. The KGOG low-risk criteria identified 181 of 319 patients as a low-risk group (51%), and three false-negative cases were found (1.9%). Despite a significant difference in the nodal metastasis rate (18.2% and 8.8%, P=.012) and the surgical policy for para-aortic lymphadenectomy (100% and 48.9%, P<.001) between the two hospitals, KGOG criteria consistently showed a very low adjusted FNR at the prevalence of 10% in both hospitals (1.8% vs. 1.1%, respectively). Among the entire study population, the adjusted FNR was 1.4% (95% confidence interval, .5% to 4.3%), which was similar to the FNR of 1.3% in our previous study.

Conclusion: The KGOG low-risk criteria accurately identified a low-risk group for lymph node metastasis with acceptable false negativity regardless of diverse clinical settings.