Tumor vascularity in cancer cases with and without evidence of the presence of endothelium-coated tumor emboli. Vascular density was determined by counting the number of vessels per unit of HPF (high power field) at magnification ×400. (A) Mean vascular density of total cases and seven cancer types, excluding FTC, HCC and RCC. Standard deviation (SD) is indicated by error bars. (B) Vascular density of individual cases for each type of cancer. The mean vascular densities are indicated by the horizontal lines. (C) Mean percentage of vascular area and SD of all cases examined and for the seven cancer types. (D) Percentage of vascular area of individual cases for each type of cancer. The mean percentages of vascular area are indicated by the horizontal lines. Solid bars and circles, cancer cases with endothelium-coated tumor emboli; open bars and circles, cases with uncoated emboli. FTC, follicular thyroid carcinoma; HCC, hepatocellular carcinoma; RCC, renal cell carcinoma. *Significant difference between cancer cases with endothelium-coated tumor emboli and with naked ones (P < 0.01).