Lymph node sampling and survival in endometrial cancer

Objective. To determine the impact of pelvic lymph node sampling on survival in women with FIGO stage I and II endometrial adenocarcinoma. Methods. We reviewed data from the National Cancer Institute's Surveillance, Epidemiology, and End Results program on 9185 women with stage I endometrial cancer and 881 women with stage II endometrial cancer. Life table analysis was used to compare survival rates. Results. Overall, lymph node sampling did not appear to convey survival benefit. The 5-year relative survival for 6363 women with stage I endometrial cancer who did not undergo lymph node sampling was 0.98, compared to 0.96 for 2831 women who did undergo lymph node sampling at the time of hysterectomy, a nonsignificant difference. Lymph node sampling (LNS) was associated with increased survival among those with stage I, grade 3 disease, but not grade 1 or grade 2. Women with stage I, grade 3 disease who underwent LNS had a relative 5-year survival of 0.89, compared to 0.81 for those who did not undergo LNS (P = 0.0110). Nonsignificantly improved survival associated with LNS for women with grade 3 disease was observed in International Federation of Gynecology and Obstetrics stages Ib, Ic, and II. Conclusions. The observed survival benefit associated with lymph node sampling may be due to identification of women with more advanced endometrial cancer. Accurate determination of grade and extent of tumor is necessary to delineate which patients may benefit from lymph node sampling at hysterectomy. Effective cooperation between surgical pathology and gynecology services may be required to ensure adequate examination of the hysterectomy specimen. A surgeon with expertise in performing lymph node sampling should be available if operative findings render lymph node sampling appropriate.