Abstract: Background and purpose: Ovarian cancer is the most common cause of death in gynecological malignancy. For patients in the early stage, the value of lymphadenectomy remains a question. This study demonstrated the relationship between lymphadenectomy and the progression-free survival outcomes of patients with early stage ovarian cancer. Methods: The information of 246 patients with International Federation of Gynecology and Obstetrics (FIGO) stage ⅠC-ⅡA ovarian cancer treated from 2001 to 2019 was collected from Fudan University Shanghai Cancer Center. The patients were divided into two groups according to the type of surgery, the pathological staging group (n=123) and the clinical staging group (n=123). And survival analysis was performed to evaluate the prognosis of patients. Multivariable regression analysis was conducted to explore the association between overall survival (OS) or progression-free survival and other variables. Meanwhile, t-test was used to compare the average operative duration, average hospitalization and the average blood loss between the pathological staging group and the clinical staging group , to explore the effect of lymphadenectomy on postoperative complications. Results: There was no significant difference in the clinical characteristics between the two groups. The 3-year, 5-year and 10-year OS rates were 91.78%, 80.77% and 45.45% in pathological staging group, and were 90.91%, 81.43% and 42.86% in the clinical staging group, respectively. Kaplan–Meier method and log-rank test demonstrated that there was no significant difference in progression-free survival (P=0.194) and OS (P=0.184) between these two groups. All patients received platinum-based adjuvant chemotherapy. The patients who received CBP+taxol for 6 courses were the most (103/246, 41.87%), and the median course of chemotherapy was 6. A total of 85 patients developed recurrent metastasis, and 78 (78/85, 91.76%) of them had metastasis in the pelvic and peritoneal cavity. During the follow-up of the patients in the pathological staging group, we found two patients with retroperitoneal lymph node metastasis while there were 3 patients in clinical staging group. Furthermore, the median operating time was longer in the pathological staging group than in clinical staging group (P<0.001). And the mean time of hospitalization was also significantly longer in the pathological staging group than in clinical staging group (P=0.016). Four patients in the pathological staging group developed postoperative complications (4/123, 3.25%), whereas only one patient in the clinical staging group developed postoperative complications (1/123, 0.81%). In the multivariate analysis model, we found that the FIGO stage was an independent predictive factor for OS, while the grade of tumor was an independent prognostic factor for both progression-free survival and OS. Lymphadenectomy was not associated with progression-free survival and OS. Conclusion: The use of lymphadenectomy did not improve the prognosis of patients. Moreover, it may increase the risk of postoperative complications due to its prolonged operating time.

Key words: Ovarian cancer, Lymphadenectomy, Prognosis