The impact of systematic retroperitoneal lymphadenectomy on long-term oncologic outcome of women with advanced ovarian clear-cell carcinoma

Objective: The impact of systematic retroperitoneal lymphadenectomy (SRL) remains controversial in patients with advanced ovarian clear-cell carcinoma (CCC) who are optimally debulked. Methods: Between 1986 and 2017, a total of 3,227 women with epithelial ovarian carcinoma were analyzed in a multi-institutional study. Among them, 166 optimally debulked women with stage IIB–IV CCC were collected (residual tumor of <1 cm). All patients were divided into 2 groups: 1) Group I (n=112): underwent standard radical surgery with SRL, 2) Group II (n=54): underwent non-staging limited surgery. The pathological slides were assessed based on central pathological review. Oncologic outcomes were compared between the two groups using a propensity score (PS)-matching technique to adjust for various clinicopathologic factors. Results: The median follow-up duration of all surviving women was 52.8 (1.6–184.2) months. Overall, 88 patients (53.0%) experienced recurrence and 68 patients (41.0%) died of the disease. In the original cohort, the 5-year overall survival (OS) rates of groups I and II were 57.9 and 64.9%, respectively (log-rank p=0.415). In the PS-adjusted cohort, the 5-year OS rates were 64.9 and 58.8% in women in groups I and II, respectively (p=0.453). Furthermore, in the PS-matched cohort after adjustment for multiple clinicopathologic factors, there was no significant difference in OS between the 2 groups (group I vs. group II; hazard ratio=1.170; 95% confidence interval=0.633–2.187; p=0.615). Conclusions: This study suggests that the performance of SRL including radical surgery may not lead to a significant improvement in the oncologic outcome of advanced CCC patients with optimal cytoreduction.