Evaluation of Clinical Significance of Lymphovascular Space Invasion in Stage IA Endometrial Cancer

Introduction: The prognostic significance of lymphovascular space invasion (LVSI) in stage IA endometrial cancer remains unclear. The aim of this study was to evaluate the clinical significance of LVSI in stage IA endometrial cancer. Methods: Clinical data of patients with stage IA endometrial cancer who underwent initial surgery at our institution between January 2008 and December 2018 were reviewed retrospectively. Information of patients, surgery, and characteristics of cancer were obtained from medical records and pathological reports. Results: Two hundred ninety-seven patients were enrolled in this study. With a median follow-up of 60 months, 15 patients experienced recurrence (5.1%) and 4 patients died of endometrial cancer (1.3%). The recurrence and mortality rates did not differ significantly between the LVSI-positive and-negative groups (p = 0.07 and p = 0.41, respectively). Recurrence-free survival and endometrial cancer-specific survival also did not differ significantly between these groups (p = 0.11 and p = 0.49, respectively). The 5-year endometrial cancer-specific survival rates for tumors with and without LVSI were 97.0% and 98.9%, respectively. Among patients with low-grade tumors, recurrence-free survival and endometrial cancer-specific survival did not differ significantly between patients with tumors with and without LVSI (p = 0.92 and p = 0.72, respectively). The 5-year endometrial cancer-specific survival rates for low-grade tumors with and without LVSI were 100% and 99.3%, respectively. Conclusion: LVSI was not a prognostic factor of not only stage IA endometrial cancer but also stage IA low-grade cancer.