Update on sentinel node mapping in uterine cancer: 10-year experience at Memorial Sloan-Kettering Cancer Center

Endometrial cancer is the most common gynecologic malignancy. In the majority of patients, the disease will present at an early stage, without metastasis, and with an excellent prognosis. Although the rate of metastasis in patients with early stage endometrial cancer is low, the standard of treatment still includes a complete or selective pelvic and para-aortic lymphadenectomy for staging. Many patients will undergo a comprehensive lymphadenectomy despite having disease confined to the uterus, resulting in detrimental side-effects, including lower extremity lymphedema. Recent studies, such as 'A Study in the Treatment of Endometrial Cancer', have shown that there is no therapeutic benefit to a complete lymphadenectomy in early stage endometrial cancer, although further study is needed to confirm these findings. The use of sentinel lymph node (SLN) mapping in endometrial cancer may provide an appropriate middle ground between the two schools of thought of complete lymphadenectomy versus no nodal evaluation. SLN mapping, which is gaining ever-increasing acceptance in many cancer types, is based on the concept that lymph node metastasis is the result of an orderly process, that is, the lymph drains in a specific pattern away from the tumor, and therefore if the SLN, or first node, is negative for metastasis, then the nodes after the SLN should also be negative. We present here the Memorial Sloan-Kettering Cancer Center experience with SLN mapping in uterine cancer, a technique we first began using in 2003 and have improved over the years.