Surgical Staging Widely accepted management of endometrial cancer consists of hysterectomy, removal of remaining adnexal structures, and appropriate surgical staging in patients considered at risk for extrauterine disease (132–134). Surgical staging was recommended for patients with endometrial cancer since 1988 (134). In spite of this general recommendation, the incorporation of a systematic pelvic and para-aortic lymphadenectomy in all patients is not universally accepted (135–137). This recommendation became more controversial after the publication of two large prospective randomized trials that failed to demonstrate improved outcomes for patients who underwent pelvic lymphadenectomy (138,139). These two studies show differences in their design: in the ASTEC trial all women with clinical stage I were included without exclusion criteria, whereas the Italian study excluded women with stage IA and IB grade 1 tumors, and nonendometrioid malignancies. In the Italian study, systematic nodal dissection was performed, as opposed to pelvic node sampling in the ASTEC trial (median number of lymph nodes harvested 30 vs. 12, respectively). The studies share characteristics that could lead to misinterpretation of their results. The percentage of nodal positivity is low in both studies (13% and 9%), suggesting that regardless of differences in exclusion criteria, low-risk cases were included in both studies, thus diluting possible (if any) therapeutic benefit of lymphadenectomy. Another important limitation is that nodal dissection was limited to the pelvis without any recommendation for para-aortic lymphadenectomy. It was demonstrated previously that radiotherapy limited to the pelvis does not improve survival (136). It is not surprising that pelvic lymphadenectomy alone has no therapeutic impact, considering that 67% of patients with nodal involvement have paraaortic lymph node metastases and 16% of patients with documented lymphatic dissemination have isolated para-aortic metastases (140). Neither study used the information derived from lymphadenectomy to target postoperative treatment (i.e., to spare patients with negative nodes from radiotherapy or to target postoperative treatment to the metastatic areas), thus eliminating one of the potential benefits of this surgical procedure.
Systematic pelvic and para-aortic lymphadenectomy remains one of the most important steps to assess the presence of extrauterine disease and to guide targeted postoperative treatment. GOG33 demonstrated that patients with absent or superficial myometrial invasion have a low probability of lymphatic metastases (141). Furthermore, Mariani et al. demonstrated that no patient with endometrioid grade 1 or 2 disease and superficial myometrial invasion harbored a lymphatic metastasis when the tumor diameter was 2 cm or less (137). The importance of tumor size as a predictor for lymphatic spread was reported by Schink et al. (142). It is possible to identify a group of patients in whom lymphadenectomy is likely to increase the risk of surgical complications without producing any concrete benefits. Tumor diameter, along with myometrial invasion and histologic grade and subtype, can be utilized to determine whether or not lymphadenectomy is appropriate.