Obstetrics and Gynecology International feasible and more economic imaging method with accuracy comparable with MRI and it can be proposed as ﬁrst-line option for evaluation of myometrial invasions and cervical spread [31]. Some imaging modalities can also investigate the status of lymph nodes, but the results, to date, have been disappoint- ing. MRI and CT/PET are statistically comparable, but have only a limited speciﬁcity in detecting pelvic and paraaortic node metastasis [29, 30]. 4. Intraoperative Detection of Lymph Node Metastasis There is currently no validated method for predicting lymph node metastasis. Accordingly, many authors support a comprehensive surgical staging for endometrial cancer. Although intraoperative evaluation methods for lymph node metastasis, as frozen section examination and node palpations, are often used in surgical oncological practice, there is scientiﬁc agreement that they are inaccurate. 4.1. Lymph Node Palpation. Girardi et al. found that 37% of nodal metastases were less than 2 mm and only 7% larger than 2 cm [32]. Several authors demonstrated the high false- negative rates for intraoperative lymph node palpation (26% by Eltabbakh and 36% by Arango et al.) [33, 34]. 4.2. Frozen Section. The incidence of lymph node metastasis is related to the depth of invasion and tumor grade. Intraoperative frozen section might identify patients who are at risk for extrauterine spread and required complete surgical staging. Frozen section may help to further stratify for the risk of ﬁnal pathology but is not entirely accurate [35]. To date, available evidence does not clearly support modulating the extent of surgical staging according to the results of frozen section examination. Case et al. evaluated in a prospective-blinded study the accuracy of frozen section in surgical management of endometrial cancer. There was a poor correlation between frozen and ﬁnal section: only 67% for invasion depth and 58% for tumour grade. This study demonstrated a clini- cally relevant upstaging in 18% of patient who underwent lymphadenectomy [36]. Another study by Frumovitz et al. veriﬁed that the combination of intraoperative frozen section analysis for histological grade and depth of myometrial invasion correlates poorly with ﬁnal pathologic grade and stage in patients with apparent grade I and II tumor [37]. The ﬁnding of negative pelvic nodes at intraoperative frozen section has been proposed to guide further surgical management during surgical staging of endometrial cancer. A recent study by Papadia et al. conﬁrmed that frozen section underestimated the risk of lymph node involvement in 16% of cases when compared with ﬁnal section pathology [38]. Another trial by Pristauz et al. veriﬁed that intraoperative frozen section of pelvic nodes is not accurate to tailor the extent of lymphadenectomy. In this study, examination of 3 pelvic nodes had a sensitivity of 41% and a false negative rate of 59% [39]. 4.3. Sentinel Lymph Node Examination. In an eﬀort to decrease the morbidity resulting from lymphadenectomy, several authors proposed the sentinel lymph node (SN) detection approach. Although it is still under investigation, this technique has several potential beneﬁts in surgical management of endometrial cancer. Data on feasibility and utility are rapidly increasing. However, few studies have concluded the feasibility of SN in endometrial cancer [40– 50]. It has been veriﬁed by many authors that SN detection may help to evaluate regional lymphatic status and to select the group of patients that must be submitted to a complete lymphadenectomy, avoiding surgical invasiveness in early stage cancer [49, 50]. Most investigators performed intramyometrial or intracervical punctures [40–50]. The identiﬁcation rates were 61.5% to 67%, when blue dye was injected into the subserosal myometrium of the fundus, and 83% by additional injections of blue dye into the cervix [40]. The modern trend in lymphatic mapping for endometrial cancer is through subendometrial hysteroscopic injection. Delaloye et al. published a study evaluating hysteroscopic injection of patent blue dye and radioactive tracer beneath the tumour of 60 patients with endometrial carcinoma, sentinel nodes were identiﬁed in 49 of 60 patients (82%) [50]. 5. Extent of Lymphadenectomy Actually, the extent and anatomical limits of lymphadenec- tomy in endometrial cancer is another topic of scientiﬁc debate. The GOG (Gynaecologic Oncology Group) has standardized the surgical limits of pelvic and paraaortic lymphadenectomy including the genitofemoral nerve later- ally, the hypogastric artery medially, the obturator nerve posteriorly, the circumﬂex iliac vein caudally, and inferior mesenteric artery (IMA) as cranial limit when performing paraaortic lymphadenectomy [51]. 5.1. Paraaortic Lymphadenectomy: To Do or Not To Do? Retroperitoneal lymph node metastasis is a signiﬁcant prog- nostic factor for patients with endometrial cancer. The risk of paraaortic nodal metastasis can be related to the presence of adnexal metastasis and/or pelvic lymph nodes metastasis: paraaortic lymph nodes are positive in 38%–52% of cases with positive pelvic lymph nodes, in 20%–57% with adnexal metastasis, and in only 2% with negative pelvic nodes [52]. In other trials, a range from 28.6% to 66.7% of patients with pelvic metastasis had concomitant positive paraaortic nodes [5, 52–54]. Mariani et al. demonstrated that 47% of patients with pelvic lymph nodes metastasis also have positive paraaortic lymph nodes or will submit a relapse in paraaortic region [20]. Furthermore there are reports in literature showing that increasing number of positive pelvic nodes is associ- ated with paraaortic metastasis [55, 56]. Fujimoto et al. reported the therapeutic signiﬁcance of complete paraaortic