Sentinel lymph node sampling versus full lymphadenectomy in endometrial cancer: a SEER database analysis

Objective: To assess the long term outcomes and prognosis of sentinel lymph node sampling compared with full lymph node dissection in endometrial cancer patients.

Methods: We used the Surveillance, Epidemiology, and End Results (SEER) database for information on women diagnosed with endometrial cancer from 2010 to 2019. We conducted a comparison including overall survival between patients who had undergone sentinel lymph node sampling only and patients who had undergone formal lymph node dissection. Propensity score matching was performed according to the patient's age, type of endometrial cancer, grade and stage of disease, and adjuvant therapy. Subgroup analyses were performed according to type and grade of endometrial cancer.

Results: 41411 endometrial cancer patients were identified through the database. After matching, 6019 patients each were included in the sentinel lymph node and lymph node dissection groups. Median (interquartile range (IQR)) follow-up time was 16 (7-31) months in both groups. One year survival rates were longer in the sentinel lymph node group compared with the lymph node dissection group (hazard ratio (HR) 1.61 (95% confidence interval (CI) 1.17 to 2.21); p=0.004). Subgroups analysis according to grade of disease showed that 1 year survival rates were longer in the sentinel lymph node group in patients with endometrioid-type grade 1-2 endometrial cancer (HR 1.70 (95% CI 1.31 to 2.56); p=0.01), while no difference in survival was found between the sentinel lymph node and lymph node dissection groups in the subgroup of patients with high grade endometrial cancer (HR 1.40 (95%CI 0.94 to 2.24); p=0.17). In patients with low grade endometrial cancer included in the sentinel lymph node group, only 7% had lymph nodes positive for malignancy compared with 17% in the high grade group.

Conclusion: Survival rates were not compromised in endometrial cancer patients undergoing sentinel lymph node sampling versus full lymph node dissection for all grades of disease.