PSM-adjusted OS and BCSS of patients with dnMBC (Stratified by molecular subtype). Kaplan-Meier (K-M) survival analysis: OS of dnMBC patients with (A) HR+/HER2- subtype, (B) HR+/HER2+ subtype, (C) HR-/HER2+ subtype, (D) HR-/HER2- subtype; and BCSS of dnMBC patients with (E) HR+/HER2- subtype, (F) HR+/HER2+ subtype, (G) HR-/HER2+ subtype, (H) HR-/HER2- subtype. OS: overall survival; BCSS: breast cancer-specific survival; dnMBC: de novo metastatic breast cancer; HR: hormone receptor; HER2: human epidermal growth factor receptor 2; PSM: Propensity score matching; BH: Multiple comparisons were corrected by the Benjamini & Hochberg method; NS: neoadjuvant systemic therapy followed with surgery; SC: surgery followed with chemotherapy; CW: chemotherapy without surgery.