Determinants of pelvic and para-aortic lymph node metastasis in endometrial cancer and its role in tailoring lymphadenectomy

Objectives: Complete lymphadenectomy may be omitted in selected cases in which the risk of lymph node spread is low (low-risk cancer). In this study, we aimed to study the various clinicopathologic variables affecting lymph node metastasis, to evaluate the incidence and distribution of pelvic lymph nodes (PLN) and paraaortic lymph node (PALN) metastases in endometrial cancer, and to study intraoperative and postoperative complications of pelvic and para-aortic lymphadenectomy. Methods: Our study included 78 patients with endometrial cancer between June 2005 and May 2011. The surgical procedure involved peritoneal cytology, total or radical hysterectomy, and bilateral salpingooophorectomywith pelvic and para-aortic lymphadenectomy. Statistical analysiswas performed using Fisher's exact probability test, and P b 0.05 was considered statistically significant. Results: Positive LN metastasis was diagnosed in 41% of patients: 23% with PLN and PALN metastasis, 10.3% with PLN metastasis only, and 7.7% with PALN metastasis only. The most commonly involved PLN groups were internal iliac and obturator LNs (67.9% and 61.5%). In the aortic area, the most commonly involved group (66.6%) was the preaortic LNs (supraand inframesentric). PLN and PALN metastasis in stages III and IV was significantly higher than in stages I and II. Myometrial invasion, cervical invasion, adnexal metastasis, and lymphovascular invasion were significantly correlated with PLN metastasis, while myometrial invasion, adnexal metastasis, and lymphovascular invasion were significantly correlated with PALN metastasis. Postoperative complications were observed in 50 patients (64.1%). The most common complication was pelvic lymphocysts in 46.1%. Ileus and deep venous thrombosis were seen in 7.6%. None of the complications resulted in death. Conclusions: Our findings suggest that systemic lymphadenectomy can be omitted in endometrial carcinoma patients who have favorable clinicopathological determinants (stage I, endometroid type, myometrial invasion b50%, and absence of lymphovascular invasion) because of low risk for LN metastasis and to avoid perioperative complications. However, these results should be confirmed in prospective large-scale, randomized clinical trials.