Abstract
Breast cancer remains one of the leading causes of cancer-related mortality in women worldwide. A key driver of tumor progression and resistance to therapy is abnormal vascularization, which leads to heterogeneous blood flow, hypoxia, impaired drug delivery, and increased malignancy. Emerging clinical evidence suggests that breast tumor Doppler ultrasound parameters can predict pathological response to neoadjuvant chemotherapy, highlighting the potential of tumor blood flow as a prognostic biomarker. In this context, strategies to modulate tumor perfusion-particularly through non-pharmacological approaches-are of growing interest. Exercise has shown promise in promoting vascular remodeling, improving oxygenation, and enhancing treatment efficacy. This narrative review discusses current evidence on the role of tumor blood flow in disease progression and therapeutic response, with special emphasis on the modulatory effects of exercise training. We also explore how tumor blood flow is assessed, briefly outlining key methodologies such as Doppler ultrasound, contrast-enhanced imaging, and perfusion-related biomarkers, and their relevance for interpreting exercise-induced vascular adaptations, its association with tumor aggressiveness, and the interplay between exercise and oncological therapies. Understanding how exercise influences tumor hemodynamics may pave the way for innovative adjuvant strategies in breast cancer management.