The significance of systemic immune-inflammation index (SII) and age in vulvar squamous cell carcinoma: a retrospective analysis of prognostic factors

Background: This study aimed to evaluate the significance of the systemic immune-inflammation index (SII) and age in patients with vulvar squamous cell carcinoma (VSCC). Methods: We conducted a retrospective analysis of 79 VSCC patients treated at a tertiary cancer center between 1998–2021. SII was calculated as (neutrophil × platelet)/lymphocyte count. Optimal cutoff values were determined by receiver operating characteristic (ROC) curve analysis. Survival outcomes were analyzed using Kaplan-Meier and Cox regression methods. Results: Patients with high SII (≥497.975) had significantly higher rates of lymph node metastasis (p = 0.036, independent t-test with Welch’s correction). Age >65 years was associated with worse 5-year overall survival (OS) (70.7% vs. 83.5%, p = 0.003) and increased nodal involvement (p = 0.02). Multivariate analysis identified age >70 years (hazard ratio (HR) = 2.41, 95% confidence interval (CI): 1.32–4.39) and advanced International Federation of Gynecology and Obstetrics (FIGO) stage (HR = 3.02, 95% CI: 1.85–4.93) as independent prognostic factors. Conclusions: SII shows promise as a predictor of nodal metastasis in VSCC, while advanced age significantly impacts survival outcomes. These findings may help guide risk stratification and treatment decisions for this rare malignancy.

Vulvar squamous cell carcinoma; Systemic immune-inflammation index; Prognostic factors; Lymph node metastasis

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