In BC patients who received neoadjuvant chemotherapy but not without received neoadjuvant chemotherapy, we found that those exhibiting a high expression of COL4A1 had longer OS and RFS periods than those exhibiting a low expression as determined via Kaplan–Meier analysis (P=0.047 and P=0.026, Figures 4(a) and 4(b)). Here, COL4A1 is linked to breast cancer.