Dr AlHilali Consultant Clinical Oncologist

A closer look · Understanding a diagnosis

Stage and grade.
Different questions.

Stage describes the extent of a cancer. Grade describes features assessed under the microscope. Explore them separately, then put the information together.

A concept lesson, not a staging tool. The spread diagrams use generic regions, not real anatomy. The microscope examples show one cancer type. No selection assigns a numbered stage, a prognosis or a treatment.

Question A / Extent

Where is the cancer?

Illustrative locationsNot a stage map

Three generic regions illustrating cancer extentAbstract confined-disease example: cancer symbols appear only inside the generic starting organ. This is not real anatomy or a numbered-stage diagram.Starting organNearby regionDistant organFilled circles: illustrative cancer locationsSeparate examples, not an inevitable sequence

Confined to the starting organ

This example illustrates cancer limited to its organ of origin. It does not tell us the numbered stage, the grade or whether an operation is possible.

Nearby tissue or regional nodes

This example illustrates involvement of nearby tissue and/or regional lymph nodes. The effect on staging depends on the cancer and its classification system.

Spread to a distant site

This example illustrates distant spread from the original cancer. The tumour type and other findings still matter. The drawing is not a complete staging assessment.

Question B / Microscope appearance

What does the tissue show?

Three colorectal adenocarcinoma micrographs labelled well differentiated, moderately differentiated and poorly differentiated.
Three different colorectal adenocarcinoma specimens, not a sequence of changes in one tumour. The outline highlights the chosen panel; the full source image and its labels remain visible. Micrographs: Zhou P, Cao Y, Li M, Ma Y, Chen C and Gan X; labels: Mikael Häggström, M.D. Original source · CC BY 4.0. Existing resized image reused unchanged; a selection outline is added by the page.

Well differentiated

In this colorectal example, the cancer retains more recognisable gland-like organisation. Differentiation contributes to grading; a pathologist applies the relevant criteria to the specimen.

Moderately differentiated

This separate colorectal example retains some gland-like organisation. The distinction depends on pathological assessment, not on a visitor matching a picture to their own report.

Poorly differentiated

This separate colorectal example shows less recognisable gland-like organisation. It illustrates one aspect of grading in this cancer type. It does not reveal how far the cancer has spread.

The extent and microscope examples describe different features. Changing one does not automatically determine the other.

Read the explanation

Stage: extent in the body

Staging can use the original tumour, involvement of nearby structures or lymph nodes, and distant spread. Many solid cancers use TNM, but the categories and stage groups are cancer-specific.

The three drawings are deliberately not labelled stage 1, 2, 3 or 4. They cannot be used to assign a stage.

Grade: pathological features

Grade is assessed from tissue. Depending on the cancer, the system may use differentiation and other features such as cell division. The colorectal micrographs illustrate differentiation in one cancer type only.

Brain tumours, blood cancers, neuroendocrine tumours and other cancers may use different classifications. A grade needs to be read with the cancer type and the grading system used.

Other information can matter too

Biomarkers and molecular findings may affect a diagnosis or treatment discussion. They do not simply replace stage or grade, and their meaning depends on the cancer. General health, previous treatment and personal priorities can also affect the plan.

Why people with the same cancer may receive different treatment

Pause and consider

Does a high grade automatically mean the cancer has spread to distant organs?

Useful next reading

Stage and grade explainedUnderstanding a pathology reportTerms for cancer extent

Sources & clinical review

Clinically reviewed and approved by Dr AlHilali on 4 November 2026.

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