Cancer staging systems

Cancer staging systems are something pathologists ought to be familiar with.

Overview

• TNM staging system - most common, and used for the most common (adult) cancers.
• World Health Organization (WHO) grading system - for CNS tumours.
• Durie-Salmon system - multiple myeloma.
• Ann Arbour system - for Hodgkin lymphoma and non-Hodgkin lymphoma (excluding mycosis fungoides and Sezary syndrome).
• St. Jude system - pediatric pathology.

TNM staging system

• Name of the system comes from the elements: Tumour, Nodes (lymph nodes), Metastasis (distant).
• Most common staging system.
• Staging parameters dependent on the specific site.

Modifiers

Table of modifiers:

Modifier	Meaning	Example	Notes
m	multiple tumours	pT(m)NM or pT2(2)N0Mx	tumour stage = highest stage of all the individual tumours
c	clinical stage	cTNM	if it is not specified clinical is assumed
p	pathologic stage	pTNM	derived from a surgical specimen or biopsy
a	stage at autopsy	aTNM	malignancy was not staged previously or treated - unless otherwise specified
y	staging after therapy	ypTNM	do not try to estimate pretreatment stage
r	recurrent tumour stage	rTNM	must have a clinically documented disease freedom

Tumour stage

Usually determined by one of the following:

1. Size of the tumour (maximal dimension).
2. Depth of invasion.

Other factors:

• Lymphovascular invasion usually does not affect the tumour stage.
  • Exceptions:
    • Seminoma.
    • Intrahepatic bile duct carcinoma.
    • Hepatocellular carcinoma.
• Margin status usually does not affect the tumour stage.
  • Exception:
    • Prostate adenocarcinoma - bladder neck margin positivity.

Nodal stage

• Lymph node involvement.
• Positive lymph nodes (without mets) often upstage to stage III.
  • May upstage to stage II in some tumours.
• Sampling may be selective (sentinel lymph nodes).

Metastasis stage

• Metastases.

See also

• Cancer.