Understanding cancer stage
What stage 0 through IV describe
The short version
Stage describes the extent of the cancer — its size, whether it has reached nearby lymph nodes, and whether it has spread elsewhere — using a scale from 0 to IV.
Staging describes the extent of a cancer at diagnosis: its size, whether it has reached nearby , and whether it has spread to other parts of the body. Breast cancer stages generally range from 0 to IV.
- Stage 0 — , contained within a milk duct
- Stage I–II — invasive cancer contained in the breast or nearby lymph nodes, generally smaller or more limited in spread
- Stage III — larger or more extensively involving nearby lymph nodes or tissue
- Stage IV — cancer that has spread to distant parts of the body
Go deeper: TNM staging
Staging is often built from three measures — Tumor size, Node involvement, and Metastasis (spread) — combined into a single overall stage. Biomarker results are also increasingly factored into some staging systems, so your specific stage may reflect more than size and spread alone.
Stage helps guide treatment planning, but it is one part of a larger picture your care team considers together with grade, biomarkers, and your overall health.
Questions you may want to ask
What is my stage, and what was it based on?
Could my stage change as more results come in?