Serum biomarker analysis of neoadjuvant chemotherapy for locally advanced breast cancer according to clinical response. (a) Pretreatment serum levels of IL-6, IL-8, MMP-9, and tissue plasminogen activator inhibitor 1 (tPAI-1) were compared between 11 patients achieving a clinical complete response (cCR) and 12 patients demonstrating no response (NR) to neoadjuvant chemotherapy (NAC). (b) Pretreatment serum levels of tPAI-1 were compared between 30 patients achieving a cCR or clinical partial response (cPR) and 12 patients demonstrating NR to NAC. (c) Serum levels of insulin-like growth factor binding protein 1 (IGFBP-1) and IL-8 measured prior to the second round of NAC were compared between 11 patients achieving a cCR and 11 patients demonstrating NR to NAC. (d) Cumulative receiver operating characteristics for responders versus nonresponders based on pretreatment serum levels of tPAI-1. Statistical significance: *P < 0.05; **P < 0.01.