MKI67 and neoplasm: There were no significant differences in intrinsic subtype, stage, risk categories, tumour size, lymph node status, oestrogen receptor (ER) status, progesterone receptor (PR) status, human epidermal growth factor receptor 2 (HER2) status, and Ki67 status between the CTC-positive and CTC-negative groups of patients (P > 0.05).