The relative rate of ecDNA is the highest for EGFR (Figure S7D), but this appears to be highly specific to CNS tumors (where 87% of EGFR amplifications are associated with ecDNA), whereas for lung tumors (where epidermal growth factor receptor [EGFR] amplification is also common) and other cancer types, the rates of ecDNA are only 11% and 21%, respectively, similar to that of other well-known oncogenes (Figure S7E). Here, EGFR is linked to central nervous system neoplasm.