Lymphovascular space involvement as a prognostic factor for survival outcomes in vulvar cancer: A systematic review and meta‐analysis

BACKGROUND: Lymphovascular space involvement (LVSI) is a significant prognostic factor of survival outcomes in gynecologic oncology. Synthetic studies on vulvar cancer are lacking as well as clear consensus about the importance of LSVI in vulvar cancer. OBJECTIVES: This study systematically evaluates the evidence of the impact of LVSI on vulvar cancer survival outcomes and explore its potential association with inguinofemoral metastases whenever relevant data were available. METHOD: We searched the international literature using the Medline, Scopus, Clinicaltrials.gov, Cochrane Central Register of Controlled Trials CENTRAL, and Google Scholar. Observational studies that compared survival outcomes among vulvar cancer patients that had positive pathology findings for LVSI and those without LVSI were included. RESULTS: Overall, 22 articles were retrieved and six were selected for inclusion. Significant differences were noted in the progression-free survinal (PFS) of patients with LVSI compared to that of patients without LVSI (hazard ratio [HR] 2.79, 95% confidence interval [CI] 1.27, 6.14). Similarly, the overall survival (OS) of patients with LVSI was substantially lower compared to that of patients without LVSI (HR 1.66, 95% CI 1.18, 2.35). None of the studies reported differences in lymphatic metastases among patients with LVSI and those without LVSI in the primary tumor site. CONCLUSION: Despite the significant heterogeneity of included studies, current data suggest that vulvar cancer patients with LVSI of the primary tumor site have worse survival outcomes. It remains unclear how much this observation is influenced by other significant factors, including the stage of the disease and positive tumor margins.