To test the MyCTC chip in a more clinically relevant setting, we applied a whole blood sample from a patient with metastatic breast cancer (Table S1) and stained the captured cells on-chip with antibodies against EPCAM, EGFR and HER2 to identify cancer cells and with antibodies against CD45 to discriminate the remaining haematopoietic cells. The gene discussed is ERBB2; the disease is cancer.