Introduction To investigate the impact of the number of retrieved lymph nodes (NRLN) in the recurrence-free survival (RFS) of patients with vulvar cancer (VC).

Methods We retrospectively included 192 patients treated for VC at the Salah Azaiez Institute between 1994 and 2022. The NRLN was stratified into 2 groups: NRLN <12 and NRLN ≥ 12. We analyzed the impact of the NRLN on RFS according to clinical and pathological factors.

Results The mean age was 64.93± 13.817 years (range, 24–104 years). Surgery consisted of a radical vulvectomy, hemivulvectoy, and pelvic exenteration in respectively 96.4%, 2.1%, and 1.6% of cases. Lymph node (LN) dissection was bilateral in 88.5% of cases and the mean number of retrieved lymph LN was 14. LN metastasis (LNM) was assessed in 67 patients (34.9%). NRLN<12 and ≥12 were recorded in respectively 31.8% and 68.2% of cases. After a mean follow-up time of 35.48±35.48 months, the 5-year RFS in patients with NRLN<12 and NRLN≥12 was 38.2% and 64.9% respectively (p=0.092). The subgroup analysis revealed that a NRLN≥12 was significantly associated with a better 5 years RFS compared to NRLN<12 in stage pT1 (70.1% vs 38.9%, p=0.016), patients staged without LNM (81% vs 46.5%, p=0.032), patients with 3 or more LNM (33.6% vs 0%, p=0.027), in case of R0 resection (74.8% vs 36.6%, p=0.005) and in the absence of lymphovascular space invasion (64.9% vs 28.7%, p=0.046)

Conclusion/Implications The removal of more than 12 LN improves VC outcomes in patients with node-positive and negative disease, pT1 stage, and complete resection.