EGFR and AIDS dementia complex: Moreover, nearly all (4 out of 5) ADC/SCC tumors with EGFR mutation as clonal events exhibited a high level of immune cell infiltration (P5N, P7N, P13N, and P14N), while the matched SCLC tumors, with clonal EGFR mutations and RB1 inactivation, demonstrated low or moderate levels of immune cell infiltration (Fig. 3A).