Effect of neoadjuvant chemotherapy on the expression of estrogen receptor(ER),progesterone receptor(PR),and Her2 in breast carcinima

Objective To compare immunohistochemical(IHC) profiles(ER, PR, Her2) of breast cancer before and after neoadjuvant chemotherapy and to assess the subsequent effects on hormone receptor status. Methods Expressions of ER,PR,Her2 of 54 patients with breast cancer were measured before and after neoadjuvant chemotherapy.Results Of the 54 carcinomas, there were 48.1% positivity for ER pre-neoadjuvant therapy and 44.4% positivity forpost-treatment(P=0.7), 40.1% positivity for PR pre-neoadjuvant therapy and 22.2% positivity for post-treatment(P=0.038), and 63% positivity for HER2 IHC pre-treatment and 61% positivity for post-treatment(P=0.843). Conclusion Neoadjuvant chemotherapy has no effect on the profiles for ER, Her2 IHC in primary breast carcinomas, and further investigation is warranted to assess reproducibility of technique and investigate clinical implications of significant loss of PR status.