The Role of Lymphadenectomy in Patients with Endometrial Cancer

Endometrial cancer (EC) represents the most common malignancy of the female genital tract in developed countries [1-10]. Current international guidelines (ACOG, FIGO, SGO, ESGO and ESMO), recommend systematic surgical staging as the initial treatment approach for all types of EC [type I (endometrioid) and type II (serous, clear cell, undifferentiated)] [2-4,6-15]. This is mainly because systematic surgical staging offers many diagnostic, prognostic and therapeutic benefits for these patients [2-4,6-13].

Pelvic and para-aortic lymphadenectomy represents an integral part of the systematic surgical staging [2][3][4][6][7][8][9][10][11]16]. Pelvic lymphadenectomy should include the remove of the nodal tissue from the distal half of the common iliac artery, the external iliac artery and vein (down to the deep circumflex iliac vein) and the obturator fat pad (anterior to the obturator nerve) [11]. In para-aortic lymphadenectomy the nodal tissue from the inferior vena cava and aorta (up to the level of either the renal vessels or to the inferior mesenteric artery) is dissected [8][9][10][11].
There is an ongoing debate regarding the need and the extent of para-aortic lymphadenectomy in EC patients, mainly because the occurrence of isolated para-aortic lymph node metastases with negative pelvic nodes, is approximately only 1-3,5% [8,11,20,29]. Based on the results of the SEPAL study, combined pelvic and para-aortic lymphadenectomy should be recommended in intermediate and high risk EC patients (stage Ib or more in type I EC and any stage in type II EC), as there are essential survival benefits [8,30]. Furthermore, the implementation of para-aortic lymphadenectomy up to the level of renal vessels is preferable, because most patients with paraaortic lymph node involvement have metastases above the level of the inferior mesenteric artery [8,29,31].
The extent of pelvic and para-aortic lymphadenectomy should be confirmed pathologically in the tissue specimen [8,11]. Although there is not any limit regarding the number of the removed lymph nodes, the removal of more than 10-12 lymph nodes is directly correlated with improved prognosis [8,11,24,26,27,32]. Consequently, the total number of the removed lymph nodes, reflects the adequacy of lymphadenectomy [8,24,26].
The most common intraoperative and postoperative complications of pelvic and para-aortic lymphadenectomy, are vessel or nerve injury, pelvic lymphocysts, lymphoedema and
In recent years, the sentinel lymph node detection and dissection has emerged as an attractive approach, mainly because it could potentially be related to reduced risk of perioperative complications compared to the systematic lymphadenectomy. Particularly in EC, sentinel lymph node dissection still remains experimental and represents a balance between systematic lymphadenectomy and no dissection in low and intermediate risk EC patients [8,[37][38][39][40][41][42]. The approach is based on the theory that lymph drains away from the tumor in a specific centrifugal pattern [38,39]. Consequently, if the sentinel lymph node is negative for metastasis, then the chance that more distal nodes are involved by tumor is very low, and therefore the need for further lymphadenectomy is not necessary [38,39].
In conclusion, pelvic and para-aortic lymphadenectomy plays an essential role in the systematic surgical staging of patients with EC [2][3][4][6][7][8][9][10][11]16]. Moreover, provides important information for the postoperative adjuvant treatment of these patients, in order to maximize the survival and minimize the morbidity of overtreatment (post-radiation effects, chemotherapy related toxicity) and the risks of under-treatment (recurrence). Provisional results of the sentinel lymph node dissection look promising and future studies would be able to show if this approach could replace the systematic lymphadenectomy.