The Role Of Para-aortic Lymphadenectomy In Epithelial Ovarian Cancer

Background and ObjectiveOvarian malignant tumor is one of the common gynecologic cancers, which has the highest mortality. Epithelial ovarian cancer comprises the majority of malignant ovarian tumor. Surgery combined with chemotherapy based on platinum is the basic therapeutic method of epithelial ovarian cancer, there are still 50%?80% recurrence of epithelial ovarian cancer after radical surgery and standard chemotherapy, the 5-year survival rate of patients with advanced stage is still around 30?40%. To date, surgical-pathological staging proposed by the International Federation of Gynecology and Obstetrics is admitted global to be the most important factor in evaluating patients' prognosis. At present, there is a controversy about the value and the extent of lymph node dissection in treatment of epithelial ovarian cancer. The aim of this study was to investigate the impact of lymph node metastasis and the extent of lymph node dissection related to recurrence, and estimate the risk factors of pelvic lymph node and para-aortic lymph node metastasis in epithelial ovarian cancer, in order to select appropriate surgical procedure.MethodsThe clinical-pathologic factors 104 patients with epithelial ovarian cancer who underwent lymphadenectomy from Jan 2012 to Nov 2015 in the Second Affiliated Hospital of Zhengzhou University were undertaken.37 patients performed pelvic lymphadenectomy and 67 patients performed united pelvic and para-aortic lymphadenectomy, respectively. The patients were divided into pelvic lyphadenectomy group and the pelvic add para-aortic lyphadenectomy group. Firstly, we calculated lymph node metastasis rate. Secondly, we compared the effects of lymph node metastasis and the extent of lymphadenectomy on the recurrence rate and survival rate of epithelial ovarian cancer. Finally, we analyzed risk factors of pelvic node and para-aortic lymph node metastasis. SPSS 21. OOsoftware was applied for statistical treatment. P value<0.05 was considered statistically significant.Results1.46(44.23%) of 104 patients had lymph node metastases,41 patients (39.42%) had pelvic lymph node metastases,24 patients (35.82%)had para-aortic lymph node metastases. In the pelvic add para-aortic lyphadenectomy group,7 patients (10.45%) only had pelvic lymph node metastases,5 patients (7.46%)only had para-aortic lymph node metastases,19 patients (28.36%)had both pelvic and para-aortic lymph node metastases.In univariate analysis, clinical stages, pathological type and cell differentiation are high risk factors of pelvic lymph node metastases; clinical stages and pelvic lymph node metastases are high risk factors of para-aortic lymph node metastases. In multivariate analysis, clinical stages is an independent high risk factor of pelvic lymph node metastases, pelvic lymph node metastases is an independent high risk factor of para-aortic lymph node metastases.2. The average number of lymph node dissection are (19.56±6.14) and (39.55±15.59) in pelvic lyphadenectomy group and the pelvic add para-aortic lyphadenectomy group, respectively. Patients with pelvic add para-aortic lymphadenectomy had higher number of resected lymph node(P<0.05). The average number of positive lymph node are (9.09±4.63) and (32.93±18.10) in pelvic lyphadenectomy group and the pelvic add para-aortic lyphadenectomy group, respectively. Patients with pelvic add para-aortic lymphadenectomy had higher number of positive lymph node(P<0.05).3. Para-aortic up to the renal vessels lymph nodes and the lymph nodes between para-aortic and inferior vena cava were the most common involved para-aortic lymph nodes.4.8 early stage cases upstage after lymphadenectomy due to lymph node metastases, accounted for 17.39%(8/46).Five cases performed pelvic add para-aortic lymphadenectomy,4 cases had lymph node metastases in both pelvic and para-aortic lymph nodes,1 case in para-aortic lymph nodes only,5 cases had lymph node metastases in the para-aortic lymph node up to the renal vessels.5.41 have recurrence in the 104 cases, the total recurrence rates is 39.42% (41/104). The recurrence rates were 60.87%(28/46) in lymph node metastasis group and 22.41%(13/58) in lymph node non-metastasis group. There were statistically significant differences between two groups(P<0.05). The recurrence rates were 54.05%(20/37) in pelvic lyphadenectomy group and 31.34%(21/67) in the pelvic add para-aortic lyphadenectomy group, respectively. There were statistically significant differences between two groups(P<0.05). The average progression-free time were(23±1.963) months and (32±1.643) months in lymph node metastasis group and lymph node non-metastasis group, the median progression-free time were 20 months and 39 months in pelvic lyphadenectomy group and the pelvic add para-aortic lyphadenectomy group, respectively. There were statistically significant differences between two groups(P<0.05).Conclusions1. In epithelial ovarian cancer, pelvic add para-aortic lymphadenectomy can find only para-aortic lymph node metastasis occult patients, improve the operation and pathological staging of patients, reduce relapse rate, and prolong the tumor-free survival period.2. Pelvic add para-aortic lymphadenectomy should be performed in epithelial ovarian cancer. Given the para-aortic up to the renal vessels lymph nodes are the most involved nodes, the extent of lymphadenectomy should up to the renal vessels.3. Pelvic add para-aortic lymphadenectomy should be performed especially for advanced disease, serous cancer and poorly differentiated ovarian cancer.