The standard of care for women with high risk endometrial cancer is the removal of all visible lymph nodes in the pelvis and lower abdomen to identify if disease has spread to these areas. It is estimated that no more than 25% of all women with presumed early stage high risk endometrial cancer will have positive lymph nodes however currently the majority of women are subjected to extensive resection of all pelvic lymph and or para-aortic lymph nodes and its associated morbidities. The objective of this study is to determine if intraoperative sentinel lymph node (SLN) mapping will improve the assessment of regional lymph nodes and enhance the detection of lymph nodes with metastatic disease in endometrial cancer. This would benefit the majority of women with early stage high risk endometrial cancer and would prevent the associated complications of pelvic lymph node dissection.