Patients' responses to breast cancer neoadjuvant chemotherapy (NACT) differ because of heterogeneous tumor characteristics. Reports about NACT progression are sporadic. Here we enrolled 1187 patients who received NACT in our cancer center between January 1, 2007, and December 31, 2016. We analyzed the characteristics and treatments of patients with progressive disease (PD) or non-PD or pathological complete response (pCR). In total, 45 (3.8%) patients had PD. PD patients were associated with a significantly worse disease-free survival (DFS) (hazard ratio (HR) = 3.77; 95% CI, 1.77 to 8.00; P =.001) and overall survival (OS) (HR = 3.85; 95% CI, 1.77 to 8.35; P =.001). For the PD patients, 28 (62.2%) patients received mastectomy immediately after PD, and 17 (37.8%) changed to chemotherapy. DFS and OS exhibited no significant differences between these two salvage therapies. After a change to second chemotherapy, 58.8% (10/17) patients had PD or SD. With the exception of tumor size, pretreatment T stage, and histology type, no other significant differences were noted between PD and pCR patients. Our results demonstrated that PD patients were associated with a significantly worse prognosis. Based on these results, we suggest to give the addition of trastuzumab to HER-2 positive patients instead of changing the chemotherapy regimen and proceeding to surgery instead of further chemotherapy once patients have PD during NACT. Given that some similar characteristics exist between PD and pCR patients, more studies to identify novel molecular markers to predict disease response to NACT should be performed.
Keywords: Breast cancer; neoadjuvant chemotherapy; predictive factor; progression; salvage therapy.