Risk of nodal metastasis associated with lymphovascular space invasion in endometrial cancer

Abstract

Objective: We conducted this study to investigate the risk of lymphovascular space invasion (LVSI) on lymph node metastasis in endometrial cancer. Methods: Between August 2017 and December 2019, we enrolled 88 consecutive patients with a preoperative histologically confirmed diagnosis of clinical stage 1 endometrioid type endometrial carcinoma, who had undergone hysterectomy and 59 of these patients required staging lymphadenectomy. We used Pearson s correlation coefficient and Mc Nemar s test for comparing LVSI and myometrial invasion to predict lymph node metastasis. Logistic regression analysis used for determining predictors for lymph node (LN) metastasis. Results: 75% of tumors with pelvic lymph node metastasis had LVSI, whereas 80% of the patients with pelvic lymph node negative tumors did not have LVSI and there was a significant correlation between LVSI and pelvic lymph node metastasis (p < 0.01). Sensitivity for LVSI in predicting pelvic lymph node involvement was 75%, specificity was 80.4%, positive predictive value (PPV) was 38% and negative predictive value (NPV) was 95.3% (p<0.05) (95% confidence interval (CI) 1.3–82, hazard ratio (HR): 10.3). Sensitivity for LVSI to predict para-aortic lymph node involvement was 85.7%, specificity 80.8%, PPV 38% and NPV 97.6% (p < 0.05) (95% CI 1.7–205 HR: 18.8). Pathological examination results with myometrial invasion more than half of the myometrium that has 75% sensitivity, 51% specificity, 19% PPV and 93% NPV for pelvic lymph node metastasis, thus, LVSI seems to have equal sensitivity but more specificity (p < 0.05). Discussion: This study demonstrates that LVSI is an independent predictor of LN metastasis for apparently Stage 1 endometrioid type endometrial carcinoma. If feasible, incorporating intraoperative frozen section analysis of LVSI may be used when deciding to perform lymphadenectomy. LVSI status is at least as important as myometrial invasion status of the tumor and LVSI may be a better indicator of lymph node metastasis.