According to the blood CEA values and CT scan, the tumor acquired resistance to anti-EGFR treatment within 9 months and plasma-Seq revealed a novel focal amplification on 17q12, including ERBB2, which represents an established mechanism of resistance to anti-EGFR therapy (Fig. 5; Additional file 3: Table S2; Additional file 2: Figure S6) [36, 60–62]. The gene discussed is ERBB2; the disease is neoplasm.