Indication of “additional” adjuvant therapy in a breast cancer patient with persisting CTC. CTC positivity: CTC+, CTC negativity: CTC-, FEC: fluorouracil, epirubicin, cyclophosphamid, RT: radiotherapy, BCS: breast conserving surgery, SLNB: sentinel lymphatic node biopsy, dg: diagnosis, IDC: invasive ductal carcinoma, G: grade, markers of stem cells: CD44/CD24, ALDH (aldehyddehydrogenase), VIM (vimentin), markers of epithelial cells: KRT18/19 (keratins), HER2: human epidermal growth factor receptor, MUC1 (mucin), markers of chemoresistance: see Table 2.