ERBB2 and breast cancer: Comparisons between BMs and primary tumors have revealed genes with increased mutation frequency in BMs, including TP53, ATR, and APC (in LUAD); ARID1A and FGF10 (in SCLC); PIK3CG, NOTCH3, and TET2 (in lung squamous cell carcinomas); ERBB2, BRCA2, and AXL1 (in BC).323