Magnetic beads coated with antibodies for the epithelial markers EpCAM, HER2, and MUC1 were applied to enrich CTCs in samples from patients with ovarian cancer, which were followed by multiplex RT-PCR for six genes (EpCAM, HER2, MUC1, WT1, P16, and paired box gene 8). The gene discussed is ERBB2; the disease is ovarian carcinoma.