Pathological Complete Response Patients after Neoadjuvant Chemotherapy in Breast Cancer.

Cases of breast cancer metastasis after achieving a pathological complete response (pCR) with neoadjuvant chemotherapy (NAC) are sometimes encountered in clinical practice. We investigated the prognostic factors for pCR in patients with breast cancer after NAC. This retrospective cohort study included patients with localized breast cancer who underwent NAC followed by surgery between 2004 and 2020 and achieved a pCR. The associations between clinical factors and distant metastasis-free survival rate were statistically analyzed. We analyzed data for 127 patients. Twelve patients (9.4%) had distant metastases, and seven (5.5%) died. For estrogen receptor (ER)-positive patients, the distant metastasis-free survival rate was 94.6% for both 5 and 8 years. In contrast, ER-negative patients had a distant metastasis-free survival rate of 87.6% and 85.4% for 5 and 8 years (p=0.094), respectively. In cT0-2 patients, the distant metastasis-free survival rate was 92.4% for 5 years and 90.5% for 8 years, whereas in cT3-4 patients, the distant metastasis-free survival rate was 83.5% for 5 years and 83.5% for 8 years (p=0.301). This study suggested that patients with ER-negative, pre-NAC cT3 or T4 breast cancer who had achieved a pCR after NAC tended to have a worse prognosis.