Abstract: Objective To evaluate the effect of lymph node dissection on the prognosis of patients with early epithelial ovarian cancer (EOC). Methods The patients with stage Ⅰ-Ⅱ EOC in our hospital from January 2008 to December 2018 were retrospectively recruited. According to whether lymph node dissection was performed, the patients were divided into an operation group without lymph node dissection (No-LND group) and a lymph node dissection group (LND group). The demographic characteristics, clinicopathological information and perioperative adverse events of the two groups were collected, and Cox proportional hazard regression was used for survival analysis. Results A total of 279 patients with EOC were enrolled, 56 cases in the No-LND group and 223 in the LND group. The median number of lymph nodes removed in the LND group was 25, including 21 pelvic lymph nodes and 4 para-aortic lymph nodes. The 5-year PFS rates of the LND group and No-LND group were 85.9% and 81.6%, respectively, and the 10-year PFS rates were 81.3% and 72.9%, respectively, with a statistically significant difference (P=0.013). The 5-year OS rates of the LND group and No-LND group were 93.8% and 88.7%, respectively, and the 10-year OS rates were 86.7% and 82.6%, respectively, with a statistically significant difference (P=0.042). Multivariable Cox regression analysis showed that lymph node dissection was a protective factor for prognosis (HR=0.89, 95%CI: 0.79-0.97, P=0.041), but the median operation time of the LND group was longer than that of No-LND group (220 min vs 155 min,  P<0.001), and the incidence of lymphatic cysts at discharge was also higher in the LND group (31.8% vs 0, P<0.001). Conclusions Lymph node dissection can improve the prognosis of patients with early EOC, but it may increase the incidence of perioperative adverse events. Therefore, the therapeutic value of lymph node dissection in the patients with early EOC still needs to be further verified by large-scale, prospective randomized controlled trials.

Key words:  Ovarian cancer, Lymph node dissection, Prognosis