A recent meta-analysis, including 39 prospective and retrospective studies found discordance rates in terms of estrogen receptor (ER), progesterone receptor (PR), and HER2 status between primary breast tumor and loco-regional or distant recurrences of 19% for ER, 31% for PR, and 10% for HER2 [16]. Here, ERBB2 is linked to breast neoplasm.