MKI67 and lymph node neoplasm: Analysis of CyCIF images showed that ~12% of tumor cells in MEL101 were positive for the KI67 proliferation marker (as were 35% of immune cells; Fig. 3a, b; Supplementary Fig. 4a); unexpectedly, this was similar to the average proportion of KI67+ tumor cells in progressing lymph node tumors in ICI-treated patients (MEL107–109; range 3% to 12% in Fig. 3a, b; Supplementary Fig. 4b).