Should We Abandon Systematic Pelvic and Paraaortic Lymphadenectomy in Low-Grade Serous Ovarian Cancer?

Low-grade serous ovarian carcinoma (LGSOC) is a rare disease that accounts for 5% of all ovarian cancers and requires surgical complete debulking. To date, the prognostic value of pelvic and paraaortic lymphadenectomy remains unclear in this population.

This retrospective cohort of patients with a diagnosis of LGSOC was registered in the Tumeurs Malignes Rares Gynécologiques national network, between January 2000 and July 2017, at 25 centers. All LGSOC were confirmed after pathological review and operated by primary debulking surgery (PDS) or interval debulking surgery after neoadjuvant chemotherapy (NACT-IDS). Primary endpoints were overall survival (OS) and progression-free survival (PFS).

A total of 126 patients were included, 86.1% were stage III/IV, and 74.6% underwent lymph node dissection (LND). According to the Completeness of Cancer Resection (CCR) score, 83.7% had complete resection. Median OS was 130 months, and median PFS was 41 months. Pelvic and paraaortic LND had no significant impact on OS (p = 0.78) or DFS (p = 0.93), and this was confirmed in subgroups (advanced stages FIGO III/IV, CCR score 0/1 or 2/3, and timing of surgery PDS or NACT-IDS). Histological positive paraaortic lymph nodes had a significant negative impact on PFS in the whole population (HR 2.21, 1.18-4.39, p = 0.02) and in the CC0/CC1 population (HR, 2.28, 1.13-4.59, p = 0.02).

Systematic pelvic and paraaortic LND in patients with LGSOC improved neither overall nor PFS. A prospective trial would be necessary to validate these results but would be difficult to conduct due to the rarity of this disease.