Doctors use several systems to stage pancreatic cancer. The method used to stage other cancers, called the TNM classification, is not often used for pancreatic cancer; however, for completeness, it is discussed below. The more common way to classify pancreatic cancer is to divide it into four categories based on whether it can be removed with surgery and where it has spread:
• Borderline resectable
This category is being increasingly used. It refers to a tumor that cannot be removed surgically when it is first diagnosed, but if chemotherapy and/or radiation therapy is able to shrink the tumor first, it may be able to be removed at a later time.
• Resectable
If the cancer is only in the pancreas (or has spread just beyond it) and the surgeon believes the entire tumor can be removed, it is called resectable. (In general, this would include most stage IA, IB, and IIA cancers in the TNM system.)
It’s important to note that some cancers might appear to be resectable based on imaging tests such as CT scans, but once the surgeon starts the operation it might become clear that not all of the cancer can be removed. If this happens, only a sample of the cancer may be removed to confirm the diagnosis (if a biopsy hasn’t been done already), and the rest of the planned operation will be stopped to help avoid the risk of major side effects.
• Unresectable
These cancers can’t be removed entirely by surgery.
Locally advanced: If the cancer has not yet spread to distant organs but it still can’t be removed completely with surgery, it is called locally advanced. Often the reason the cancer can’t be removed is because it has grown into or surrounded nearby major blood vessels. (In general, this would include stage IIB and most III cancers in the TNM system.)
Surgery to try to remove these tumors would be very unlikely to be helpful and could still have major side effects. Some type of surgery might still be done, but it would be a less involved operation with the goal of relieving symptoms or problems like a blocked bile duct or intestinal tract, not of curing the cancer.
Metastatic: If the cancer has spread to distant organs, it is called metastatic. These cancers can’t be removed completely. Surgery might still be done, but the goal would be to relieve symptoms, not to cure the cancer. Pancreatic Cancer Staging
• TNM Staging System
A staging system is a standard way for doctors to sum up how far a cancer has spread. The main system used stage cancers of the pancreas is the American Joint Committee on Cancer (AJCC) TNM system. The TNM system is based on 3 key pieces of information:
- T describes the size of the main (primary) tumor and whether it has grown outside the pancreas and into nearby organs.
- N describes the spread to nearby (regional) lymph nodes.
- M indicates whether the cancer has metastasized (spread) to other organs of the body. (The most common sites of pancreatic cancer spread are the liver, lungs, and the peritoneum — the space around the digestive organs.)
T categories
Using the TNM system, the "T" plus a letter or number (0 to 4) is used to describe the size and location of the tumor. This helps the doctor develop the best treatment plan for each patient. Specific tumor stage information listed below.
- TX: The primary tumor cannot be evaluated.
- T0: No evidence of cancer was found in the pancreas.
- Tis: Refers to carcinoma in situ (which is very early cancer that has not spread.)
- T1: The tumor is in the pancreas only, and it is 2 centimeters (cm) or smaller in size.
- T2: The tumor is in the pancreas only, and it is larger than 2 cm.
- T3: The tumor extends beyond the pancreas, but the tumor does not involve the major arteries or veins near the pancreas.
- T4: The tumor extends beyond the pancreas into major arteries or veins near the pancreas. A T4 tumor is unresectable (unable to be completely removed during surgery).
N categories
The "N" in the TNM staging system is for lymph nodes. Lymph nodes are tiny, bean-shaped organs located throughout the body that normally help fight infection and disease as part of the body's immune system. In pancreatic cancer, regional lymph nodes are those lymph nodes near the pancreas and distant lymph nodes are those lymph nodes in other parts of the body.
- NX: The regional lymph nodes cannot be evaluated.
- N0: Cancer was not found in the regional lymph nodes.
- N1: Cancer has spread to regional lymph nodes.
M categories
The "M" in the TNM system indicates whether the cancer has spread to other parts of the body.
- MX: Distant metastasis cannot be evaluated.
- M0: The disease has not spread to other parts of the body.
- M1: Cancer has spread to another part of the body, including distant lymph nodes. Pancreatic cancer most commonly spreads to the liver, peritoneum (lining of the abdominal cavity), and lungs.
Stage Grouping for Pancreatic Cancer
Once the T, N, and M categories have been determined, this information is combined to assign an overall stage of 0, I, II, III, or IV (sometimes followed by a letter). This process is called stage grouping.
- Stage 0 (Tis, N0, M0): The tumor is confined to the top layers of pancreatic duct cells and has not invaded deeper tissues. It has not spread outside of the pancreas. These tumors are sometimes referred to as pancreatic carcinoma in situ or pancreatic intraepithelial neoplasia III (PanIn III).
- Stage IA (T1, N0, M0): The tumor is confined to the pancreas and is 2 cm across or smaller (T1). It has not spread to nearby lymph nodes (N0) or distant sites (M0).
- Stage IB (T2, N0, M0): The tumor is confined to the pancreas and is larger than 2 cm across (T2). It has not spread to nearby lymph nodes (N0) or distant sites (M0).
- Stage IIA (T3, N0, M0): The tumor is growing outside the pancreas but not into major blood vessels or nerves (T3). It has not spread to nearby lymph nodes (N0) or distant sites (M0).
- Stage IIB (T1-3, N1, M0): The tumor is either confined to the pancreas or growing outside the pancreas but not into major blood vessels or nerves (T1-T3). It has spread to nearby lymph nodes (N1) but not to distant sites (M0).
- Stage III (T4, Any N, M0): The tumor is growing outside the pancreas into nearby major blood vessels or nerves (T4). It may or may not have spread to nearby lymph nodes (Any N). It has not spread to distant sites (M0).
- Stage IV (Any T, Any N, M1): The cancer has spread to distant sites (M1). Pancreatic Cancer Staging