ERBB2 and breast cancer: On the other hand, further research will be required to establish whether there are reproducible organ-distinct patterns of distant recurrence across the different molecular subtypes as well as the relationship with nodal involvement, since the probability of axillary metastasis appeared to be more strongly related to the luminal BC group, with a three times higher risk in patients with luminal B tumors, compared with patients with non-luminal HER2 tumors.