Nottingham Prognostic Index (Breast Cancer)

Nottingham Prognostic Index (NPI) for early invasive breast cancer (Haybittle 1982 / Galea 1992).

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Tumor size
2.5
Lymph-node stage
2 — 1 to 3 positive nodes
Histologic grade
2 — grade II

Result: NPI 4.5: moderate prognosis (> 3.4 to <= 5.4; ~70% 5-year survival).

The tool opens with these values already filled in. Replace them with your own.

What the result means

Groups
Excellent <= 2.4 (~93% 5-yr survival); good > 2.4 to <= 3.4 (~85%); moderate > 3.4 to <= 5.4 (~70%); poor > 5.4 (~50%).

What you enter

  • Tumor size (cm)
  • Lymph-node stage (1=0 nodes, 2=1-3, 3=>=4)
  • Histologic grade (1-3)
How this is calculated
Formula
NPI = (0.2 x tumor size in cm) + node stage + grade. Node stage 1 (0 nodes) / 2 (1-3) / 3 (>= 4); grade 1/2/3.

Galea MH, Blamey RW, Elston CE, Ellis IO. The Nottingham Prognostic Index in primary breast cancer. Breast Cancer Res Treat. 1992;22(3):207-219. (Original: Haybittle JL, et al. Br J Cancer. 1982;45(3):361-366.) Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.