Staging of pancreatic cancer:
Staging of pancreatic cancer helps the doctors figure out the on how much the cancer has spread in the pancreas and determine its best treatment. Staging also helps calculate survival statistics. The lower the number of the stage, the less is the cancer has spread, with early stages being 0 and the most advanced stage being 4.
TNM system for staging:
TNM system is the most common type of staging for pancreatic cancer, it stands for stands for Tumour, Node and Metastasis.
The size of the primary tumour (T), the presence of cancerous lymph nodes (N) and how far the pancreatic cancer has spread to a different part of the body (M) can be described using the TNM system.
Tis (carcinoma in situ) is an early stage pancreatic cancer, which hasn’t spread. Pancreatic cancers at such an early stage cannot be diagnosed.
T1 stage: This stage means that the tumour is less than 2 cm or less in the pancreas in any direction. It is further divided depending on the tumour size: T1A, T1B and T1C in the order of increasing size of tumour.
T2 stage: In this stage, the size of the tumour varies between 2 cm and 4 cm.
T3 stage:Here, the tumour is bigger than 4 cm in size.
T4 stage: In this stage,the cancer has grown out of pancreas to the nearby blood vessels.
The node describes whether the cancer has spread to the lymph nodes or not.
N0 stage: Shows that there are no lymph nodes containing cancer.
N1 stage: There is a presence of 1 to 3 cancerous lymph nodes.
N2 stage: 4 or more lymph nodes contain cancerous lymph nodes, which means that the cancer can further spread in the body.
This gives information about the cancer spreading to other parts of the body.
M0 stage: The cancer has not spread to other distant parts of the body.
M1 stage: The cancer has spread to other body parts also.
Stages of pancreatic cancer:
In this stage, the cancer has not penetrated the inner tissues of the pancreas and is confined to the top layers of the pancreatic duct cells. These tumours are known as carcinoma in situ (Tis).
Here, the staging is (Tis, N0, M0).
Treatment: Surgical treatments are used to treat stage 0 since the cancerous cells are still in the pancreas. Depending on the location of the tumour, a particular portion of the pancreas is removed. Radiation therapy and chemotherapeutic drugs are often combined with surgery for better results.
- Stage 1A: In this stage, the cancer is present only in the pancreas and the tumour is not bigger than 2 cm in size. The staging here is, (T1, N0, M0).
- Stage 1B: In this stage, the cancer has not spread to other body parts and the size of the tumour varies between 2 cm and 4 cm. The staging here (T1, N0, M0).
Treatment: At this stage, the cancer has not metastasized, so removing the tumour will remove the cancer from the body. Hence surgical treatments are the best to treat stage 1 of pancreatic cancer. The treatment might include a combination with chemotherapy or radiotherapy in rare cases.
1. Stage 2A: Here, the pancreatic cancer has not spread and the size of tumour is bigger than 4 cm in size. The staging is, (T3, N0, M0).
2. Stage 2B: The pancreatic cancer has spread to 1-3 lymph nodes with varying sizes of tumour. The staging here could be:
- (T1, N1, M0)
- (T2, N1, M0)
- (T3, N1, M0)
Treatment: Surgical procedures, chemotherapy, radiation therapy, targeted and systematic therapies are used to treat stage 2 pancreatic cancer.
In this stage, the size of the tumours could vary 1 cm to 4 cm, or even be bigger than that, along with the cancer being spread to one or more lymph nodes.
The staging here could be:
- (T1, N2, M0)
- (T2, N2, M0)
- (T3, N2, M0)
- (T4, ANY N, M0)
Treatment: Palliative surgery or stent placement or bypass blocked areas in ducts, chemotherapy followed by chemoradiation and chemoradiation followed by chemotherapy are used to treat stage 3 pancreatic cancer.
In this stage, the pancreatic cancer cells have spread to other parts of the body as well. The tumour size is bigger than 4 cm in size and there could be more number of cancerous lymph nodes.
The staging here could be (ANY T, ANY N, M1).
Treatment: Palliative treatments to relieve pain caused by nerve blocks. These surgeries or stent placements to block the bypass the blocked areas in pancreatic ducts is used to treat this stage of pancreatic cancer. Chemotherapy with or without targeted therapy is also one of the treatments for stage 4 pancreatic cancer.
Staging based on resection of tumors:
Patients who can be treated by removal of tumours from the pancreas, the extent of resection is an important factor for staging, that is whether the tumour has been removed completely or not:
- R0: The tumour has been removed completely. There are no traces of the tumour left.
- R1: The visible tumor has been removed completely, but lab tests show that some parts of cancer are still left.
- R2: Visible tumor could not be resected.
Based on whether the tumor can be resected, the staging is divided into 3 groups:
If the cancer is confined just to the pancreas and the tumor can be resected, it is known as resectable. This includes IA, IB, IIA in the TNM system.
This is when the cancer has just spread to the blood vessels, but there is a chance that it could be removed by surgery.
These cancers cannot be removed by surgery. They include cancers that are metastasized or locally advanced.