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How and why is the Tumor Staged?
MEASURING CANCER | TNM Classification | Staging | Clinical Classification
Staging cancer is a standardized way to classify a tumor based on its size, whether it has spread, and where it has spread. In other words,
staging measures the extent of the disease. 1 Your doctor will order diagnostic tests to determine the stage of your disease. Knowing the stage of your cancer will help
your doctor determine which treatment options are right for you. The stage of your cancer is the most important factor in
making good treatment choices.
Most cancers are staged using the TNM system of classification, which was developed by the American Joint Committee on Cancer
(AJCC). 2
TNM CLASSIFICATION SYSTEM
The TNM system uses three factors to evaluate cancer: tumor, node, and metastasis 1,3:
- T stands for tumor and describes the size and location of the primary tumor, if and how far it has spread within the pancreas,
and if it has spread to nearby structures.
- N stands for node and describes evidence of metastases in lymph nodes close to the pancreas, that is, whether or not the tumor
has spread to the regional lymph nodes.
- M stands for metastasis and describes evidence of distant metastases, that is, whether or not the cancer has spread to distant
parts of the body.
Tumor Evaluation (T)
Based on information from diagnostic tests, the “T” is given a number to describe the size and location of the tumor 1,4:
TX: The primary tumor cannot be evaluated
T0: No evidence of cancer is found in the pancreas
Tis: This classification is used when there is a condition called carcinoma (cancer) in situ, or Tis, meaning that the tumor
remains in a pre-invasive state and is within the pancreas
T1: The tumor is in the pancreas only, and it is 2 centimeters (cm) or smaller in size [2 cm = .80 inches]
T2: The tumor is in the pancreas only, and it is larger than 2 cm
T3: The tumor has spread to surrounding tissue near the pancreas but not to the major blood vessels
T4: The tumor extends beyond the pancreas into the major blood vessels near the pancreas; T4 tumors cannot be removed completely
by surgery
Node Evaluation (N)
Lymph nodes are small, bean-shaped structures found in the neck, underarm, groin, chest, abdomen, and pelvis – and throughout the body.
They store white blood cells, called lymphocytes, which the body uses to fight infection and disease. Lymphatic fluid circulates through lymph vessels, just as blood circulates through blood vessels. Eventually, the lymphatic fluid empties
into blood vessels in the upper chest. 5 Lymph node enlargement detected either by CT or MRI scan may indicate that cancer has spread to that lymph node. (See Question 4 on Diagnosis.) A biopsy also can be performed on lymph nodes to check for cancerous cells. The node staging method is as follows 1,4:
NX: The regional lymph nodes cannot be evaluated
N0: The cancer was not found in the regional lymph nodes
N1: The cancer has spread to the regional lymph nodes
Metastasis Evaluation (M)
Pancreatic cancer may spread locally to the lymph nodes and major blood vessels near the pancreas or to distant lymph nodes
or organs such as the liver or lungs. 6 In staging, this spread is documented as follows 1,4:
MX: Distant spread of the disease (metastasis) cannot be evaluated
M0: The disease has not spread to distant lymph nodes or to distant organs
M1: The disease has spread to distant lymph nodes or to distant organs
STAGING SYSTEM
Combining T, N, and M defines the stage of cancer. Each patient’s condition is evaluated for T, N, and M, and the descriptions
are combined to form a stage ( Figures 5-1 to 5-4 ). 1,4,7
| Stage 0:
|
Refers to cancer in situ, or the cancer has not invaded outside the ducts in which it originated (Tis, N0, M0) |
| Stage IA:
|
The tumor in the pancreas is 2 cm or smaller and has not spread to lymph nodes or other parts of the body (T1, N0, M0) |
| Stage IB:
|
The tumor in the pancreas is larger than 2 cm and has not spread to lymph nodes or other parts of the body (T2, N0, M0) |
 |
| Stage IIA:
|
The tumor extends beyond the pancreas but has not spread to nearby lymph nodes, major blood vessels, or other parts of the
body (T3, N0, M0)
|
| Stage IIB:
|
The tumor is any size and is either limited to or extends beyond the pancreas and has spread to lymph nodes but not to major
blood vessels or other parts of the body (T1, T2, T3; N1; M0)
|
 |
| Stage III:
|
The tumor has spread to nearby blood vessels, may or may not have spread to nearby lymph nodes, but the cancer has not spread
to other parts of the body (T4, any N, M0)
|
 |
| Stage IV:
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The cancer has spread to other parts of the body (any T, any N, M1) |
 |
CLINICAL CLASSIFICATION
A simpler, more descriptive staging system for pancreatic cancer is often used by doctors. This system divides cancers into
groups based on whether or not the tumor can be removed surgically. 1
| Resectable Cancer |
This type of pancreatic cancer can be surgically removed. These tumors may lie within the pancreas or extend beyond it, but
there is no involvement of the critical arteries or veins in the area. There is no evidence of any spread to areas outside
of the tissue removed during a typical surgery for pancreatic cancer. 7 (See Question 7 on Treatment.)
|
| Locally Advanced Cancer |
The cancer is confined to the area around the pancreas but cannot be surgically removed because the tumor may be intertwined
with major blood vessels and may have invaded surrounding organs. No evidence of spread to other areas of the body can be
found. 7 Metastatic Cancer The tumor has spread beyond the area of the pancreas and involves other organs, such as the liver or lungs,
or other areas of the abdomen. Unfortunately, almost half of all patients are diagnosed at this stage. 7 |
| Metastatic Cancer |
The tumor has spread beyond the area of the pancreas and involves other organs, such as the liver or lungs, or other areas
of the abdomen. Unfortunately, almost half of all patients are diagnosed at this stage. 7 Table 5-1 provides a simplified version of the information given in this section. Remember that it is important to know the stage of
you cancer to help make good treatment choices.
|
| Stage |
Classifications
for
Tumor,
Nodes,
Metastases |
Description |
Resectable |
Locally Advanced |
Metastatic |
| 0 |
Tis, N0, M0 |
Cancer is confined to cells in the pancreas; also called carcinoma in situ |
X |
|
|
| IA |
Tis, N0, M0 |
Cancer is only in the pancreas and is 2 cm or smaller |
X |
|
|
| IB |
T2, N0, M0 |
Cancer is only in the pancreas and is larger than 2 cm |
X |
|
|
| IIA |
T3, N0, M0 |
Cancer has spread beyond the pancreas but has not spread to nearby lymph nodes, major blood vessels,or other parts of the
body
|
X
Sometimes
|
X
Sometimes
|
|
| IIB |
T1, T2, or T3;N1; M0 |
Cancer either is limited to or extends beyond the pancreas, with spread to the lymph nodes but not to major blood vessels
or other parts of the body
|
X
Sometimes
|
X
Sometimes
|
|
| III |
T4, any N, M0 |
Cancer has spread to major blood vessels and possibly to the lymph odes, but not to other parts of the body |
X
Sometimes
|
X
|
|
| IV |
Any T, any N,M1 |
Cancer has spread to other parts of the body |
|
|
X
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REFERENCES ! Click reference number to return to text.
1. American Cancer Society. Pancreatic cancer. http://documents.cancer.org/116.00. Accessed April 12, 2007.
2. Exocrine pancreas. American Joint Committee on Cancer: AJCC Cancer Staging Manual. 6th ed. New York, NY: Springer, 2002;157-64.
3. Johns Hopkins Pathology. Pancreas cancer. http://pathology2.jhu.edu/PANCREAS/PANCREAS1.cfm. Accessed April 19, 2007.
4. National Cancer Institute. Pancreatic cancer (PDQ®): treatment. Health professional version. March 15, 2007. www.cancer.gov/cancertopics/pdq/
treatment/pancreatic/healthprofessional/page3. Accessed April 14, 2007.
5. Eyre HJ, Lange DP, Morris LB. Informed Decisions: The Complete Book of Cancer Diagnosis, Treatment, and Recovery. 2nd ed.
American Cancer Society–Health Content Products. Atlanta, GA; 2002.
6. Erikson RA. Pancreatic cancer. www.emedicine.com/med/topic1712.htm. Accessed April 19, 2007.
7. Freelove R, Walling AD. Pancreatic cancer: diagnosis and management. Am Fam Phys. 2006;73:485-92.
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