Prognostic Significance and Molecular Classification of Triple Negative Breast Cancer: A Systematic Review.

Area of Science:

• Oncology
• Genetics
• Molecular Biology

Background:

• Triple-negative breast cancer (TNBC) is aggressive, lacking standard therapeutic targets.
• TNBC accounts for 15-20% of breast cancers, with poor prognosis and high recurrence rates.
• Molecular subtyping is crucial for understanding TNBC heterogeneity and guiding treatment.

Purpose of the Study:

• To systematically review the prognostic significance of TNBC molecular subtypes.
• To assess the implications of these subtypes for therapeutic management.
• To identify key biomarkers for improved TNBC treatment strategies.

Main Methods:

• Comprehensive literature search of PubMed, Scopus, and Web of Science.
• Inclusion of original research on molecularly classified TNBC cohorts and clinical outcomes.
• Data extraction, synthesis, and analysis of prognostic relevance.

Main Results:

• Identified TNBC subtypes: basal-like, mesenchymal, immune-modulatory, and luminal androgen receptor (LAR).
• Basal-like TNBC shows poor prognosis; immune-modulatory TNBC has better survival, especially with high tumor-infiltrating lymphocytes.
• Mesenchymal and LAR subtypes display varied clinical behavior and treatment responses. Biomarkers like BRCA1/2 mutations and PD-L1 expression are highlighted.

Conclusions:

• Molecular classification of TNBC offers vital prognostic insights and directs therapeutic strategies.
• Integrating molecular subtyping into clinical decisions is essential for personalized TNBC treatment.
• Further research is needed to refine classification and address therapeutic gaps.