Incidence of lymph node metastases in patients with apparent early-stage endometrioid ovarian carcinoma.

The incidence of lymph node metastases for apparent early-stage endometrioid ovarian carcinoma is not well-known. We accessed the National Cancer Database and selected patients with apparent stage I endometrioid ovarian carcinoma undergoing surgery between 2004 and 2015. The rate of lymphadenectomy was 76.9%, with a median of 12.5 lymph nodes removed. The overall incidence of lymph node metastasis was 2.2%, specifically, 1.2% for grade 1, 2.2% for grade 2, and 5.1% for grade 3 tumors (p < .001). After controlling for disease sub-stage, patients with grade 2 tumors were nearly twice (OR 1.78, 95% CI 1.20 to 2.63), and patients with grade 3 tumors were nearly 4 times (OR 4.1, 95% CI 2.74 to 6.22) as likely as those with grade 1 tumor to have lymph node metastases. Surgical staging identifies a very low rate of lymph node metastases for patients with apparent early-stage grade 1 endometrioid ovarian carcinoma, suggesting that lymphadenectomy can be omitted for these patients.