The stage of a cancer tells the doctor about its size and whether it has spread. The tests and scans you have when diagnosing your cancer give some information about the stage.
Doctors use the stage of a cancer to help them decide on treatment. Your doctor may not be able to tell you the exact stage of your cancer until after your surgery, if you are able to have it.
There are different ways of staging cancers. The two main ways are the TNM system and number system.
TNM stands for Tumour, Node, Metastasis. This system describes the size of the cancer (T), whether there are cancer cells in the
Tis (carcinoma in situ) is very early stage pancreatic cancer. It hasn't grown into the deeper layers of tissue within the pancreas. It is uncommon for pancreatic cancer to be diagnosed this early.
T1 means the cancer is inside the pancreas and is 2cm or less in any direction.
T1 is split into 3 stages:
- T1a means the cancer is no more than 0.5cm
- T1b means the cancer is more than 0.5cm but less than 1cm
- T1c means the cancer is between 1cm and 2cm
T2 means the cancer is between 2cm and 4cm in any direction.
T3 means the cancer is bigger than 4cm but is still within the pancreas.
T4 means the cancer has grown outside the pancreas, into the nearby large blood vessels.
Node (N) describes whether the cancer has spread to the lymph nodes.
N0 means there are no cancer cells in the nearby lymph nodes.
N1 means there are 1 to 3 lymph nodes that contain cancer cells.
N2 means that there is cancer in 4 or more lymph nodes.
Cancer that has spread to the nearby lymph nodes means there is a higher risk that cancer cells may have spread further than the pancreas.
Metastasis (M) describes whether the cancer has spread to a different part of the body.
M0 means the cancer has not spread to other areas of the body such as the liver or lungs.
M1 means the cancer has spread to other areas of the body.
The stage of your cancer helps your doctor to decide which treatment you need. Treatment also depends on:
- your type of cancer (the type of cells the cancer started in)
- where the cancer is
- other health conditions that you have
The stage of the cancer and these other factors can also give an idea of your outlook (prognosis).
The grade of the cancer means how normal or abnormal the cells look under a microscope. It can give some idea of how quickly a cancer might grow and whether it is likely to spread.
Exocrine pancreatic cancers include the most common type called adenocarcinoma. Grading for these cancers uses a scale from 1 (low grade) to 3 (high grade).
Grade 1 cancer cells look the most like normal cells. They are low grade and might grow slowly. Your doctor may call them well differentiated.
Grade 2 cancer cells look more abnormal. They are called intermediate grade or moderately differentiated.
Grade 3 cancer cells look very abnormal. They are high grade and are likely to grow or spread more quickly. Your doctor may call them poorly differentiated.
Grading for pancreatic neuroendocrine tumors (NETs)
The NET grading system is a little different. This system looks at how normal or abnormal the cells are and also at how many cells are in the process of dividing. A specialist doctor (pathologist) looks at the cells under a microscope and counts those that have started to split into two new cells (mitoses). They use a test called a Ki-67 test to see how many cells are almost ready to start splitting.