EGFR and neoplasm: Next, to determine whether the tumor cells showing amplification of 7p12 and those showing gain of 11q13 of case 4 were really limited to the MU and SM, respectively, we analyzed tissue sections from case 4 by immunohistochemistry with antibodies against EGFR, which was amplified only in the MU portion (Figure 2E), and CTTN, which was gained only in the SM portion (Figure 2F).