ABCB1 and breast cancer: Previous studies have reported that response to paclitaxel in ovarian cancer patients together with paclitaxel‐induced neutropenia and neuropathy were related to biallelic polymorphism at the 2677 and 3435 loci of ABCB1.6, 7 Another study showed that ABCB1 2677 and 3435 variants in advanced breast cancer patients were associated with disease control rates and overall survival.8 In gastric cancer ABCB1 polymorphism at 3435 sites was also related to clinical outcomes after paclitaxel‐contained chemotherapy.9