The Risk of Lymph Node Metastasis With Positive Peritoneal Cytology in Endometrial Cancer

Abstract

ObjectiveTo determine the correlation between positive peritoneal cytology (PPC) and lymph node metastasis in patients with endometrial cancer grossly confined to the uterus.MethodsData were extracted from the Surveillance, Epidemiology, and End Results database between 1988 and 2005. Only patients with endometrial cancer grossly confined to the uterus who had undergone a complete staging procedure (lymph node removal) were included. Statistical analysis used the χ2test and logistic regression models.ResultsA total of 22,947 patients were identified. Positive peritoneal cytology was present in 3.5% of the patients. The incidence of lymph node metastasis was significantly higher among patients with PPC compared to those with negative peritoneal cytology for all histologic types examined (P< 0.0001): endometrioid adenocarcinoma, 28.7% versus 6.9%; adenocarcinoma not otherwise specified, 35.4% versus 5.8%; clear cell/serous carcinoma, 41.4% versus 19.0%, and carcinosarcoma,; 38.4% versus 14.4%. After adjusting for other contributing factors in the multivariable model, PPC remained an independent predictor of lymph node metastasis (P< 0.0001).ConclusionOur data indicate that patients with positive washings are at significant risk of nodal metastasis and adverse prognosis. Although no longer a part of the current International Federation of Gynecology and Obstetrics staging criteria, peritoneal cytology status should continue to inform clinical decision making in endometrial cancer.