The stage of a cancer tells you its size and whether it has spread. It helps determine how serious the cancer is and which treatments are best.
Doctors use several systems to stage pancreatic cancer. Two of the most common are the numbering system and the TNM classification system.
A common way to classify pancreatic cancer is to classify a tumour into one of four numbers or categories, based on whether it can be removed with surgery and where it has spread.
Stage I / Localised
This is the earliest stage. The cancer is contained inside the pancreas. There is no sign that it has spread anywhere else in the body. This type of pancreatic cancer can be surgically removed. Sometimes, additional treatment may be recommended before surgery to help shrink the tumour. Approximately 10% to 15% of patients are diagnosed with this stage.
Stage II / Borderline resectable
The cancer has started to grow outside the pancreas into nearby tissues and/or there is cancer in lymph nodes near the pancreas.
Doctors often call stages I and II resectable or early-stage cancer. Resectable means a surgeon may be able to remove (resect) the tumour. Fewer than 1 in 5 cancers of the pancreas (20%) are diagnosed at this stage.
Stage III / Locally advanced
This type of pancreatic cancer is located in the areas around the pancreas, but it cannot be surgically removed because it has grown into or close to nearby arteries, veins, or organs. The cancer may have spread into the stomach, spleen, large bowel or into the large blood vessels near the pancreas, but hasn’t spread to distant sites of the body such as the liver or lungs. Approximately 35% to 40% of patients are diagnosed with this stage.
Stage IV / Metastatic
The cancer has spread to distant sites such as the liver or lungs. Stage IV cancer is often called metastatic cancer. This means that the cancer cannot be removed by surgery — but other treatments such as chemotherapy might be suggested. Approximately 45% to 55% of patients are diagnosed with this stage.
TNM classification system
One of the most common methods used to stage cancers is called the “TNM classification”. However, the TNM classification is not always used for pancreatic cancer.
The TNM staging system stands for tumour, node and metastases.
- T describes the size of the tumour (cancer)
- N describes whether there are any cancer cells in the lymph nodes. Lymph nodes are small, bean-shaped collections of immune cells. Many types of cancer often spread to nearby lymph nodes before they reach other parts of the body.
- M describes whether the cancer has spread to a different part of the body
Your doctor gives each letter (T, N and M) a number, depending on how far the cancer has grown.
These numbers are explained in the table below.
The TNM staging system
|T (Tumour)||The extent (size) of the primary tumour|
|T0||There is no evidence of a primary tumour (it cannot be found).|
|Tis||The cancer cells are only growing in the most superficial layer of the tissue, without growing into deeper tissues. This may also be called in-situ cancer or pre-cancer.|
|T1, T2, T3, T4||Numbers after the T may describe the size of the tumour and / or the amount of spread into nearby structures.|
|N (Nodes)||The spread to nearby lymph nodes|
|N0||Means the nearby lymph nodes do not contain cancer.|
|Numbers after the N may describe the size, location or number of lymph nodes affected.|
|M (Metastasis)||The spread (metastasis) to distant sites|
|M0||Means that no distant cancer spread was found.|
|M1||Means the cancer has spread to distant organs or tissues.|
The T, N and M assessments will be combined to create one overall series of letters and numbers to indicate your TNM staging. For example, Tis N0 M0 would indicate that the cancer cells are only growing in the most superficial layer of tissue, the nearby lymph nodes do not contain cancer, and the cancer has not spread.
The stage of your cancer determines the prognosis, which refers to the outlook of your cancer: the lower the stage the better the outlook.
Determining the stage is fundamental in order to make the right decision about the treatment.