How is pancreatic cancer staged?
The TNM system for pancreatic cancer
The most commonly used system to stage pancreatic cancer is the American Joint Committee on Cancer TNM system.
The first step in staging is to find the value for each part of the TNM system. Here's what the letters stand for in the TNM system:
T is the size of the tumor in the pancreas and if it has grown into nearby blood vessels outside the pancreas. The tumor size is measured by centimeters (cm).
N refers to whether any lymph nodes near the original tumor have cancer in them.
M is whether the cancer has spread ( metastasized) to other, distant organs in the body, like the liver, bones, or lungs.
Numbers or letters after T, N, and M provide more details about each of these factors. There are also two other values that can be assigned:
X means the provider does not have enough information to tell the extent of the main tumor (TX), or if the lymph nodes have cancer cells in them (NX).
0 means no sign of cancer, such as no sign of spread to the lymph nodes (N0).
What are the stage groupings of pancreatic cancer?
To find the stage of your cancer, your healthcare provider first assigns numbers for the T, N, and M groups. These numbers are then combined in a process called stage grouping to give an overall description of the cancer. A stage grouping can have a value of 0 or Roman numeral I (1), II (2), III (3), or IV (4). The higher the number, the more advanced the cancer is. Letters and numbers can be used after the Roman numeral to give more details.
These are the stage groupings of pancreatic cancer and what they mean:
Stage 0. The cancer is only in the innermost layers of cells lining the pancreatic duct. It has not invaded the deeper layers or spread anywhere else outside the duct. This may be called pancreatic cancer in situ.
Stage I. The cancer has not spread to lymph nodes or other parts of the body. This stage is divided into two groups:
Stage II. The cancer has not spread to organs in other parts of the body. This stage is divided into two groups:
Stage III. The cancer has not spread to organs in other parts of the body. This stage can be any one of the following:
The cancer is only found inside the pancreas. It’s no larger than 2 cm across. It has spread to 4 or more nearby lymph nodes.
The cancer is only found inside the pancreas. It’s more than 2 cm but less than 4 cm across. It has spread to 4 or more nearby lymph nodes.
The cancer is only found inside the pancreas. It’s larger than 4 cm across. It has spread to 4 or more nearby lymph nodes.
The cancer has grown outside the pancreas and into large blood vessels that are nearby. It may or may not have spread to nearby lymph nodes.
Stage IV. The cancer is any size and has spread to organs farther away from the pancreas. These might include the liver, lining of the abdomen (called the peritoneum), bones, or lungs.
Resectable, borderline resectable, locally advanced, and metastatic cancer
Healthcare providers use the TNM system to formally stage pancreatic cancer. But for practical reasons, they often use a simpler system when trying to decide the best treatment. They may divide cancer into these three main groups using the results of imaging tests done before surgery. The following groups are based on whether the cancer can be removed (resected) with surgery:
These cancers can be surgically removed. This includes many cancers that are still confined within the pancreas or have not grown into important blood vessels near the cancer.
Borderline resectable cancer
These cancers might be able to be surgically removed. But they are very close to nearby blood vessels. For these cancers, treatments other than surgery might be tried first to try to shrink the tumor and make it resectable.
These cancers can't fully be removed with surgery:
Locally advanced cancer. These cancers have spread or grown close to or into nearby blood vessels. lymph nodes, tissues, and organs. They can't be fully removed with surgery. Surgery may still be done to relieve symptoms, but not to try to cure the cancer.
Metastatic cancer. These cancers have spread to distant parts of the body, including distant lymph nodes (Stage IV). So they can't be removed completely with surgery. Surgery may still be done. But it's used to relieve symptoms, not to try to cure the cancer.