Accuracy of preoperative tests in clinical stage I endometrial cancer: The importance of lymphadenectomy

Objective. To evaluate the accuracy of preoperative tests for endometrial cancer in predicting the need for lymphadenectomy. Design. Retrospective study. Setting. Tertiary university hospital. Sample. One hundred and eighty-two patients diagnosed with clinical stage I endometrial cancer. Methods. Review of medical records of the patients preoperatively diagnosed with stage I disease at Yonsei University Health System between April 2000 and December 2007. Main outcome measures. Preoperative assessment of the tumor grade, depth of myometrial invasion and lymph node metastases were compared with final pathologic results. Survival was analyzed by Cox multivariate regression analysis. Results. In 104 cases with preoperative tumor grade 1, the final pathology was upgraded in 19 cases (18.3%). MRI correctly differentiated among stage Ia, Ib and Ic disease in 58.2% (106/182) of patients. Of the 166 patients undergoing lymphadenectomy, 20 (12.0%) had retroperitoneal lymph node metastases. The sensitivity and specificity of MRI for detection of lymph node metastases was 45% and 80.8%, respectively. Myometrial invasion (hazard ratio 17.14, p 0.037) and lymph node metastases (hazard ratio 8.94, p 0.042) were independent prognostic factors for overall survival. Conclusions. Incorrect decisions might be made for a substantial number of patients based on preoperative tests. Full systematic lymphadenectomy is necessary to accurately determine the extent of the disease and to guide correct decision making about tailoring adjuvant therapy, even in patients suspected of early stage disease by preoperative tests.