Fig. 1

The metastatic pattern of six human melanoma xenograft models. Histological preparations showing metastatic growth in lymph node (a) and lung (b). C-10, D-12, and E-13 tumors showed lower incidence of lymph node metastasis (c) and higher incidence of pulmonary metastasis (d) than N-15, R-18, and T-22 tumors. The percentage of mice that showed metastatic growth was used as a parameter for incidence of metastasis. Columns and bars: mean values ± standard error of four experiments, each involving 10–15 mice per melanoma model. The experiments were carried out by using adult (8–12 weeks of age) female BALB/c nu/nu mice as host animals