Breast Care A-Z · Concept · GRADESTAGE

Grade and stage

also: tumour grade, cancer grade, cancer stage, TNM staging, Bloom-Richardson, Nottingham grade

Grade describes how abnormal cancer cells look under the microscope and how quickly they are likely to grow; stage describes how large a cancer is and how far it has spread. You may have a histology report mentioning "grade 2" or "stage IIA" and wondered whether they mean the same thing — they don't, and the distinction matters.

Quick answers

Is grade or stage more important?

Both. Stage is the strongest single predictor of outcome — particularly the difference between Stage I/II and Stage III/IV. Grade refines that picture and influences treatment decisions, particularly around chemotherapy. Modern decision-making uses both, often combined with receptor status and (in selected cases) genomic tests.

My cancer is Grade 3 — does that mean it's worse?

Grade 3 cancers grow faster and look more abnormal under the microscope. The outlook depends on the full picture — a small Grade 3 cancer that is fully removed and treated appropriately can have an excellent outlook. Grade in isolation is not the whole story.

Why are there different staging systems mentioned?

Anatomic TNM is the longest-established system. Prognostic TNM, which combines anatomic stage with grade, ER, PR, HER2 (and sometimes Oncotype DX score), gives a more accurate prediction of outcome. Pathology reports often quote both. The treatment recommendation is based on the combined picture rather than on TNM alone.

PLATE XLVI ONCOLOGY · TUMOUR CLASSIFICATION grade and stage Nottingham histological grade · TNM staging system the two fundamental axes of breast cancer classification — grade describes tumour biology, stage describes extent of spread 1 FIG 01 Grade × Stage Prognosis Matrix Histological Grade ▲ TNM Stage ▶ Grade 3 Grade 2 Grade 1 Stage I Stage II Stage III Stage IV ★ ~99% 5-yr survival ✕ ~28% 5-yr survival i Grade 1: well-differentiated, score 3–5 ii Grade 3: poorly differentiated, score 7–9 iii Stage I: T1N0M0 iv Stage IV: any T, any N, M1 v grade × stage = prognosis matrix NOTTINGHAM GRADE COMPONENTS Tubule formation >75% = 1 | 10–75% = 2 | <10% = 3 Nuclear pleomorphism small uniform = 1 | moderate = 2 | large irreg = 3 Mitotic count low = 1 | intermediate = 2 | high = 3 Score 3–5 = Gr1 · 6–7 = Gr2 · 8–9 = Gr3 TNM STAGING SUMMARY T Tumour T1 ≤2cm · T2 2–5cm · T3 >5cm · T4 chest/skin N Nodes N0 none · N1 ipsilateral · N2 fixed · N3 supra M Mets M0 none · M1 distant metastasis 2 FIG 02 Grade 1 vs Grade 3 — Feature Comparison Feature Grade 1 (well-differentiated) Grade 3 (poorly differentiated) Tubule formation >75% tubule formation <10% tubule formation Nuclear size Small, regular, uniform Large, irregular, pleomorphic Mitotic count Low (<8/10HPF) High (>18/10HPF) Growth rate Slow Rapid Ki67 index Low (<15%) High (>30%) ER status Usually ER+ More often ER− Prognosis Excellent Less favourable Nottingham score 3–5 8–9 5-yr survival ~90–95% ~60–70% Chemotherapy Often not needed Usually indicated 3 FIG 03 TNM Staging — Survival Data Stage TNM Criteria Approx 5-yr Survival Stage I T1N0M0 (≤2cm, no nodes) ~99% Stage IIA T2N0 or T1N1 ~93% Stage IIB T2N1 or T3N0 ~80% Stage IIIA T0–3N2 or T3N1 ~72% Stage IIIB T4 any N ~55% Stage IIIC Any T, N3 ~50% Stage IV Any T, Any N, M1 ~28% Stage 0 DCIS only >98% Recurrent After complete response Highly variable 4 FIG 04 Diagnostic & Classification Pipeline Core biopsy (grade from histology) Receptor testing (ER/PR/HER2/Ki67) Imaging staging (CT ± bone scan) TNM classification Overall stage MDT treatment decision From tissue sample to MDT decision — the complete classification pathway Grade determined from histology; stage from imaging and pathology combined Both required for individualised treatment planning 5 FIG 05 Classification Categories at a Glance Grade 1 well-differentiated Grade 2 moderately differentiated Grade 3 poorly differentiated Stage I early, localised Stage II–III locally advanced Stage IV metastatic 6 FIG 06 Key Survival Statistics ~90% Grade 1: 5-year survival [1] ~60% Grade 3: 5-year survival [1] ~99% Stage I: 5-year survival [2] ~28% Stage IV: 5-year survival [2] 7 FIG 07 References & Further Reading 1. Elston CW, Ellis IO. Nottingham grading system. Histopathology 1991;19:403 2. Cancer Research UK. Breast cancer survival by stage 2024 3. Singletary SE et al. AJCC Cancer Staging Manual 7th ed. 2010 4. NICE NG101. Early and locally advanced breast cancer 2023 5. WHO Classification of Tumours: Breast 5th ed. IARC 2022 Clinically authored by Dr Fiona Tsang-Wright , FRCS (Gen Surg) GMC 4549831 · ORCID 0000-0003-4801-026X
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Definition
Grade describes how aggressive a breast cancer's cells appear under the microscope, scored 1 to 3; stage describes how far the cancer has spread, scored 0 to IV — these are two distinct features of a cancer, not the same thing, and both inform treatment decisions.

Common questions The questions patients ask first

Is grade or stage more important?
Both. Stage is the strongest single predictor of outcome — particularly the difference between Stage I/II and Stage III/IV6. Grade refines that picture and influences treatment decisions, particularly around chemotherapy2. Modern decision-making uses both, often combined with receptor status and (in selected cases) genomic tests45.
My cancer is Grade 3 — does that mean it's worse?
Grade 3 cancers grow faster and look more abnormal under the microscope. The outlook depends on the full picture — a small Grade 3 cancer that is fully removed and treated appropriately can have an excellent outlook. Grade in isolation is not the whole story.
Why are there different staging systems mentioned?
Anatomic TNM is the longest-established system. Prognostic TNM, introduced in the AJCC 8th edition1, combines anatomic stage with grade, ER, PR, HER2 (and sometimes Oncotype DX score) to give a more accurate prediction of outcome. Pathology reports often quote both. The treatment recommendation is based on the combined picture rather than on TNM alone3.
Will my stage change after surgery?
Pre-operative staging is based on imaging and biopsy. Post-operative staging incorporates the operation findings — particularly the actual lymph node status from the sentinel biopsy or axillary clearance, and the final pathology measurements of the cancer. The surgical specimen often gives a more accurate stage than pre-operative imaging alone, sometimes upstaging or downstaging the cancer.

Grade describes how aggressive a breast cancer’s cells appear under the microscope, scored 1 to 3; stage describes how far the cancer has spread, scored 0 to IV — these are two distinct features of a cancer, not the same thing, and both inform treatment decisions.

Grade is about the cancer’s cells (how abnormal they look). Stage is about the cancer’s extent (how big it is and whether it has spread). A small but aggressive-looking cancer can be Grade 3 / Stage I; a large slow-growing cancer can be Grade 1 / Stage III. Both are part of the picture, and the treatment plan depends on both.

Orientation Why you might be reading about this

You may have just received a histology report mentioning “grade 2” or “stage IIA” and wondered what they mean — or whether they mean the same thing. They don’t, and the distinction matters. This page explains both, how they are determined, and how they fit into the overall treatment plan.

Related terms: Invasive ductal carcinoma · Invasive lobular carcinoma · Oestrogen receptor · HER2 · Sentinel lymph node biopsy

Grade Grade — how the cells look under the microscope

The pathologist examines the cancer cells and scores them on three features:

  1. Tubule formation — how much the cancer cells still look like normal breast ducts.
  2. Nuclear pleomorphism — how variable and abnormal the cell nuclei look.
  3. Mitotic count — how often the cells are dividing (visible as cells caught in the process of division).

Each feature scores 1 (well-differentiated, near normal), 2 (moderate), or 3 (poorly differentiated, very abnormal). The three scores are added to give a total of 3–9, then translated into one of three grades2:

  • Grade 1 (total 3–5) — well-differentiated. Cells still look fairly similar to normal breast tissue. Typically slower-growing.
  • Grade 2 (total 6–7) — moderately differentiated.
  • Grade 3 (total 8–9) — poorly differentiated. Cells look very abnormal, often dividing rapidly. Typically faster-growing.

This system is called the Nottingham grading system (or Nottingham combined histological grade, sometimes still called the Bloom-Richardson system after the original authors)2. It is the standard worldwide for breast cancer7.

A higher grade does not automatically mean a worse outcome — it usually means a faster-growing cancer, which can be a treatment advantage when chemotherapy is given (faster-growing cancers often respond more dramatically to chemotherapy). The grade is one part of the picture, not the whole.

Stage Stage — how far the cancer has spread

Stage describes the cancer’s extent. The standard system is TNM — three components combined into an overall stage1:

T — Tumour size and local spread

  • T1 — 20 mm or smaller.
  • T2 — more than 20 mm up to 50 mm.
  • T3 — more than 50 mm.
  • T4 — any size with extension to chest wall (T4a) or skin (T4b), both (T4c), or inflammatory carcinoma (T4d).

N — Lymph node involvement

  • N0 — no cancer in lymph nodes.
  • pN1 — 1{nd}3 axillary nodes and/or internal mammary micrometastases on SLNB.
  • pN2 — 4{nd}9 axillary nodes, or clinically detected internal mammary nodes.
  • pN3 — ≥10 axillary nodes, infraclavicular nodes, both axillary and internal mammary involvement, or supraclavicular nodes.

M — Metastasis (distant spread)

  • M0 — no distant spread.
  • M1 — distant spread (to bones, liver, lung, or other organs).

Combined stage

The T, N, and M components are combined into an overall stage from 0 to IV1:

  • Stage 0 — DCIS (and Paget disease of the nipple without an underlying mass). LCIS is no longer staged under TNM 8 and is regarded as a risk marker rather than cancer.
  • Stage I — small tumour, no or minimal lymph node involvement, no distant spread.
  • Stage II — moderate-sized tumour, or some lymph node involvement.
  • Stage III — larger tumour or significant lymph node involvement, no distant spread.
  • Stage IV — distant spread (also called metastatic or advanced breast cancer).

The TNM system has been refined in recent years to include prognostic stage — a system that combines TNM with grade, ER, PR, and HER2 status to give a more accurate prognostic picture than anatomic TNM alone1.

Together Grade and stage together

The two features are independent and both matter. Examples:

  • A 1.5 cm Grade 1 cancer with no lymph node involvement is Stage I, low grade — typically a good outlook with relatively gentle treatment (surgery + hormone therapy, often without chemotherapy).
  • A 1.5 cm Grade 3 cancer with no lymph node involvement is also Stage I, but with cells that look more aggressive — chemotherapy may be considered alongside hormone therapy and HER2-targeted therapy if relevant.
  • A 4 cm Grade 1 cancer with one positive lymph node is Stage IIB, low grade — a different shape of treatment plan from either of the above.
  • A 4 cm Grade 3 cancer with three positive nodes is Stage IIIA, high grade — typically the most intensive treatment combination.

The full picture also includes oestrogen-receptor status and HER2 status. Together, these features feed into the multidisciplinary team’s recommendation for surgery, radiotherapy, and systemic therapy3.

Genomic tests Modern genomic tests — adding to the picture

For some early-stage, ER-positive cancers, genomic tests measure the activity of dozens of genes in the cancer and provide a more refined estimate of recurrence risk than grade and stage alone5. NICE DG58 recommends EndoPredict, Oncotype DX or Prosigna in ER/PR-positive, HER2-negative, lymph-node-negative early breast cancer where the chemotherapy decision is finely balanced. MammaPrint is not currently recommended by NICE for routine NHS use4.

At consultation What to discuss at consultation

Once the histology is back:

  • What grade was the cancer, and what does that mean in context with size and lymph node status?
  • What stage is it, in TNM and combined-stage terms?
  • Is a genomic test being considered to refine the chemotherapy decision?
  • What does this combination predict in terms of likely recurrence risk and the planned treatment intensity?

Grade and stage together shape the treatment recommendation; a second-opinion consultation is a usual way to review that plan before treatment starts.

Resources Further reading

Sources & guidance

Every figure on this page is anchored to a published source. Tap a number in the text or below to jump to the reference.

  1. reference text Amin MB, Edge SB, Greene FL, et al. (eds.); American Joint Committee on Cancer. AJCC Cancer Staging Manual, 8th edition — Breast (Chapter 48). Springer / AJCC. 2017 ;Chapter 48, Breast doi:10.1007/978-3-319-40618-3 Cited for: TNM definitions (T1–T4, N0–N3, M0/M1); anatomic and prognostic stage groupings; Stage 0 = in-situ disease.
  2. cohort Elston CW, Ellis IO. Pathological prognostic factors in breast cancer. I. The value of histological grade in breast cancer: experience from a large study with long-term follow-up. Histopathology. 1991 ;19(5):403–410 doi:10.1111/j.1365-2559.1991.tb00229.x Cited for: Nottingham combined histological grade (Bloom–Richardson refinement) — tubule formation, nuclear pleomorphism, mitotic count; 3–9 score translated into Grade 1/2/3.
  3. guideline National Institute for Health and Care Excellence (NICE). Early and locally advanced breast cancer: diagnosis and management (NG101). London: NICE. 2018 ;Last updated 2024 https://www.nice.org.uk/guidance/ng101 Cited for: UK standard pathway for grading, staging and treatment selection in early breast cancer.
  4. guideline National Institute for Health and Care Excellence (NICE). Tumour profiling tests to guide adjuvant chemotherapy decisions in early breast cancer (DG34). London: NICE. 2018 ;Last reviewed 2025 https://www.nice.org.uk/guidance/dg34 Cited for: UK recommendation for genomic profiling (Oncotype DX, EndoPredict, Prosigna, MammaPrint) to inform chemotherapy decisions in ER+/HER2−/N0 early breast cancer.
  5. rct Sparano JA, Gray RJ, Makower DF, et al. Adjuvant chemotherapy guided by a 21-gene expression assay in breast cancer (TAILORx). New England Journal of Medicine. 2018 ;379(2):111–121 doi:10.1056/NEJMoa1804710 Cited for: Genomic recurrence-score guided chemotherapy decisions; refines treatment selection beyond grade and stage in ER+/HER2−/N0 disease.
  6. meta analysis Early Breast Cancer Trialists' Collaborative Group (EBCTCG). Effect of radiotherapy after breast-conserving surgery on 10-year recurrence and 15-year breast cancer death: meta-analysis of individual patient data for 10,801 women in 17 randomised trials. Lancet. 2011 ;378(9804):1707–1716 doi:10.1016/S0140-6736(11)61629-2 Cited for: Stage / nodal status as the strongest single anatomic predictor of long-term outcome; survival differences across stages I–IV.
  7. reference text WHO Classification of Tumours Editorial Board. Breast Tumours. WHO Classification of Tumours, 5th edition, vol. 2. Lyon: International Agency for Research on Cancer. 2019 https://tumourclassification.iarc.who.int/ Cited for: Histopathological grading framework and tumour-type classification used worldwide.