FLT4 and ovarian cancer: The high histological grade was related to low expression of VEGF-C (p = 0.006), VEGF-D (p = 0.04), VEGFR1 (p < 0.001), VEGFR2 (p = 0.008) and VEGFR3 (p = 0.004) in epithelial cells of the primary ovarian cancer.