Association of antitumor activity of lenvatinib with tumor vasculature in 19 human tumor xenograft models. Lenvatinib was administered orally twice daily for 7 days, when tumor volumes reached approximately 100–300 mm3. Each group consisted of 5 mice. (A) Antitumor activity of lenvatinib in 19 human tumor xenograft models. The ΔT/C (%) was presented as a mean. □: The lenvatinib-sensitive group; ■: the lenvatinib-relatively resistant group. The relationship between the antitumor activity and MVD is shown in (B), and that between the antitumor activity and the % of pericyte coverage of vessels is shown in (C). Each symbol (○) indicates the mean of MVD or pericyte coverage in each tumor xenograft model. (D) Vascular score in the lenvatinib-sensitive and –relatively resistant groups. The vascular score was the sum of the MVD and pericyte coverage scores.