Invasive breast cancer

1. Big picture

Invasive breast cancer is a malignant breast tumor that has crossed the basement membrane and can therefore invade lymphatics, blood vessels, regional lymph nodes, and distant organs.

For the surgery exam, the core logic is:

Breast symptom or screening abnormality
        ↓
Triple assessment: examination + imaging + biopsy
        ↓
Confirm invasive cancer and biological subtype
        ↓
Stage: local tumor + axilla + distant metastasis
        ↓
Choose treatment sequence:
early operable → surgery first
locally advanced/aggressive biology → neoadjuvant therapy first
metastatic → systemic/palliative, surgery only selected cases

The surgical goal is locoregional tumor control, accurate staging, and choosing the least mutilating operation that is still oncologically safe.

---