Altered cell adhesion and prostaglandin signalling have also been observed in T-DM1-resistant oesophageal carcinoma cells.55 These changes might promote migration, survival or MAPK signalling, which could affect T-DM1 transit or the response of the cell to microtubule depolymerisation, but the translatability of findings in oesophageal cancer models to HER2-positive breast cancer might be limited. This evidence concerns the gene ERBB2 and breast carcinoma.