Although a combination of prospective and retrospective cohort study involving 131 cases of advanced stage invasive breast cancer (which have received neoadjuvant chemotherapy) indicated that the expression of ABCB1 had no significant statistical correlation to metastases (p = 0.659) [67], whether ABCB1 has any effect on tumor cell migration, which has not been clearly studied, is an undergoing project we are studying. Here, ABCB1 is linked to neoplasm.