The growing number of tumor-agnostic targets (e.g., BRCA1/2, HER2, NTRK1/2/3, BRAF v600E, RET, FGFR1/2/3, IDH1, homologous recombination deficiency, and high microsatellite instability and tumor mutational burden) in combination with targets of ongoing clinical trials (e.g., BRAF Class II/II and KRAS) justify the use of multigene NGS in most patients with a good Eastern Cooperative Oncology Group performance status (ECOG PS) and who could derive clinical benefit from a resulting therapy. The gene discussed is ERBB2; the disease is neoplasm.