As EV and subpopulations of PD-L1EV/PD-L2EV provide tumor-supporting characteristics within the tumor microenvironment [2–5], their pre- and post-CT levels were analyzed with respect to presence or absence of specific CTC subpopulations including AKT2, ALK, AR, AURKA, BRCA1, KIT, MET, EGFR, ERCC1, ERBB2, ERBB3, KRT4, mTOR, NOTCH 1, PARP1, PIK3CA, SRC. This evidence concerns the gene ERBB2 and neoplasm.