Extended data figure 2. Clinical data on the melanomas used in this study and summary of their metastatic behavior in NSG mice.

a) Summary of the clinical characteristics of the melanomas used in this study at the time of banking, as well as patient outcome after banking, and metastasis patterns upon transplantation of banked tumours into NSG mice. Melanomas were stratified into efficient and inefficient metastasizers. Efficient metastasizers formed distant metastases in patients and in NSG mice. Inefficient metastasizers did not form distant metastases in patients or distant macrometastases in NSG mice. They did form micrometastases in the lung, but not outside of the lung in the period of time it took for subcutaneous tumours to grow to 2 cm in diameter (when the mice had to be euthanized in these experiments²⁷). Nonetheless, most of the inefficient metastasizers have the ability to form macrometastases if given enough time (data not shown). b) Growth rates of subcutaneous tumours in NSG mice after subcutaneous transplantation of 100 cells. Statistical significance was assessed using two-tailed Student’s t-test. c) Clinical characteristics of the patients from whom melanomas were obtained at the time of banking and upon subsequent clinical follow up. The tumours were confirmed to be melanomas by clinical dermatopathology. The tumours were independently confirmed to be melanomas after xenografting in mice by histological and flow cytometric analysis of melanoma markers (Extended data figure 1) as well as examination by a clinical dermatopathologist.