Lymphatic microvessel density as a novel prognostic factor in early-stage invasive cervical cancer

Few data on the influence of lymphatic microvessel density (MVD) on survival in cancer are available since until recently there was no reliable immunohistological marker for lymphatic endothelium. Using an antibody staining podoplanin, a novel marker for lymphatic endothelium, lymphatic MVD in tissue samples of 85 patients with cervical cancer classification pT1b treated by radical hysterectomy was investigated. Survival was determined using univariate and multivariate analyses. Lymphatic MVD was also compared to MVD assessed by immunostaining against factor VIII-related antigen, which is considered a marker for blood vessels. Patients with >5 lymphatic microvessels/0.25 mm(2) field had significantly better overall survival (mean 91.8 months) than those with < or =5 lymphatic microvessels/field in univariate analysis (mean 113 months) (p = 0.0105, log-rank test). In multivariate analysis, lymphatic node involvement (p =0.0183), vessel infiltration (p =0.0158) and lymphatic MVD (p =0.0269) remained independent prognostic factors. No correlation between lymphatic MVD and various clinical and histopathological parameters was observed. Correlation between lymphatic MVD and MVD assessed by immunostaining against factor VIII was only weak (p = 0.004, r = 0.312, Spearman's coefficient of correlation). Our results suggest that increased lymphatic MVD is associated with favorable prognosis in early-stage cervical cancer.