MKI67 and hepatocellular carcinoma: To further investigate the association of exosomal circRNA-100,338 in serum with MVD and Ki-67 expression of both HCC primary and pulmonary metastatic tissues, we classified the 13 patients with pulmonary metastasis into high ratio ((Post/Pre)high, n = 8) and low ratio ((Post/Pre)low, n = 5) groups with the threshold at 1.2 (mean of the ratios).