Predictive Factors for Non-Response to Neoadjuvant Chemotherapy for Breast Cancer

ABSTRACT

Purpose@#Neoadjuvant chemotherapy (NAC) can effectively downstage locally advanced breast cancer; however, in some cases the cancer remains clinically stable and in others, there is disease progression. Although factors predictive of the response to NAC have been established, those for a non-response remain unknown. This study investigated factors predicting a stable or progressive disease course, and the extent of the response, after NAC based on anthracycline and cyclophosphamide (AC), with or without taxane. @*Methods@#Data were collected retrospectively by reviewing medical records of patients who received NAC for breast cancer using AC, with or without taxane between January 2013 and December 2017. Patients with clinically stable or progressive disease after NAC were compared statistically with those who achieved a partial or complete response. @*Results@#In total, 297 patients received NAC with AC and 196 patients received AC followed by taxane. Of these, 45 (15.2%) and 64 (32.6%) patients respectively, showed no response (i.e., stable or progressive disease). Factors related to non-response after AC included large pretreatment tumor size, clinical T3 status, and high histologic grade. Factors related to non-response after taxane included clinical T3 status and estrogen receptor or progesterone receptor positivity. @*Conclusion@#Clinical T3 stage, grade III histological grade, and estrogen or progesterone receptor positivity were predictors of no response to NAC for breast cancer.