COL4A1 and neoplasm: As shown in Table 1, low COL4A1 expression in tumors was significantly associated with tumor metastasis (P=0.034), but no significant association was found in those over aged 65 (P=0.421), with late-stage tumors (P=0.058), with positive ER expression (P=0.092), with positive PR expression (P=0.257), positive HER2 expression (P=0.647), or who received neoadjuvant chemotherapy (P=0.742).