Preoperative Neutrophil-to-Lymphocyte Ratio Is Associated with Lymphovascular Space Invasion and Nodal Metastasis in Vulvar Squamous Cell Carcinoma

Background: Prognosis in vulvar squamous cell carcinoma (VSCC) is strongly influenced by lymph node involvement and adverse clinicopathological features. Systemic inflammatory indices derived from blood counts may reflect tumor–host interactions associated with adverse pathological phenotypes. Objective: To assess associations of preoperative neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR) with nodal metastasis, lymphovascular space invasion (LVSI), and tumor size. Methods: This retrospective single-center study included 93 surgically treated patients between March 2017 and February 2026. Results: NLR was associated with nodal metastasis (unadjusted p = 0.015; false discovery rate [FDR]-adjusted q = 0.047) and LVSI (unadjusted p < 0.001; FDR-adjusted q = 0.006). NLR showed modest discrimination for nodal metastasis (area under the receiver operating characteristic curve [AUC] = 0.647). For LVSI, NLR had the highest AUC among the evaluated markers (AUC = 0.789; 95% confidence interval [CI]: 0.683–0.894), but 16 cases were positive and the positive predictive value (PPV) was low (0.378). Nominal MLR findings for LVSI and large tumor size did not remain significant after FDR correction (both q = 0.308), while PLR showed no consistent associations. Elevated NLR was associated with nodal metastasis in univariable analysis (odds ratio [OR] = 3.291; p = 0.012) but not in multivariable models including LVSI (adjusted OR = 1.296; p = 0.654) or excluding LVSI (adjusted OR = 1.823; p = 0.261). Conclusions: NLR was associated with adverse pathological features but was not independently associated with nodal metastasis and should not be used as a standalone predictive or clinical decision-making tool.