In estrogen receptor (ER)-positive breast cancer (BC), young age is associated with poor prognosis. While very young patients respond better to chemotherapy, chemotherapy is less effective in ER-positive tumors than in ER-negative tumors. The authors tried to evaluate chemotherapy response of very young patients with ERpositive BC by pathologic complete response (pCR) after neoadjuvant chemotherapy excluding the effect of endocrine treatment to the extent possible. |