ERBB2 and metastatic neoplasm: As in the whole study population, in each recurrence subgroup, changes were mostly observed for patients whose tumours were HER2-negative or HER2-low at diagnosis: 89.3% of metastatic tumours (117 cases) and 98.3% of local recurrences (59 cases) with a changed HER2 status developed from primary tumours which were HER2-negative or -low at diagnosis.