Breast-cancer biomarkers are measurable molecular or cellular signatures that guide screening, therapy selection, and recurrence surveillance. They sit at the core of precision oncology, turning heterogeneous tumor biology into actionable data. The Breast Cancer Biomarkers market size is valued at USD 4.1 billion in 2025 and is projected to reach USD 7.9 billion by 2033, translating to a CAGR of 8.6% during the forecast period. This robust growth outlook reflects accelerating adoption of companion diagnostics, expanding reimbursement for multigene panels, and heightened demand for minimally-liquid-biopsy alternatives. North America remains the largest revenue contributor on the back of dense screening infrastructure and favorable CPT coding, while Asia-Pacific emerges as the fastest-expanding region, underpinned by rising incidence, health-tech FDI, and cost-efficient sequencing hubs.