Grading and staging of bladder cancer

The exact stage can often only be determined after surgery when the pathologists have examined the cancer. The whole process can take a few weeks. This can be an anxious time and, while you’re waiting for your results, you may need support from your family, friends or support organisations|.

For early bladder cancer Back to top

Grading

Grading refers to the appearance of the cancer cells| under the microscope. The grade gives an idea of how quickly the cancer may develop. Low grade means that the cancer cells look very much like normal bladder cells. They are usually slow growing and less likely to spread. In high-grade tumours the cells look very abnormal. They are likely to grow more quickly. Some bladder cancers are classified as intermediate grade, which is between low and high grade. In bladder cancer, carcinoma in situ (CIS) is always high grade.

Grading early bladder cancer is important. It helps your doctor to decide if you need extra treatment after the cancer has been removed.

Staging

A cancer’s stage describes its size and whether it has spread. Once your doctors know the stage of your bladder cancer they can decide on the most appropriate treatment for you.

The most commonly used staging system is the TNM system:

• T is the size of the tumour (cancer)
• N is whether it has spread to the nearby lymph nodes (sometimes called glands)
• M is whether the cancer has spread to other parts of the body (metastases).

 

Early bladder cancer is always N0 (node zero) because it hasn’t spread to the lymph nodes. It’s also always M0 (metastases zero) because it hasn’t spread to other parts of the body (metastases).

The stages of early bladder cancer

CIS (carcinoma in situ) is sometimes described as a flat tumour. Cancer cells are only in the very inner layer of the bladder lining.  

Ta The cancer is a mushroom-like growth (papillary cancer) but is still only in the very inner layer of the bladder lining.

T1 The cancer has now started to grow into the layer of connective tissue beneath the bladder lining, which is made up of supportive cells.

 

For invasive and advanced bladder cancer Back to top

Grading

The grade of a cancer gives an idea of how quickly it may develop. To find the grade of your cancer, your doctors will look at a sample of the cancer cells under the microscope. It may be graded as:

• Grade 1 - The cancer cells tend to grow slowly and look quite similar to normal cells (ie are ‘well differentiated’). They are less likely to spread than grade 2 or grade 3 cancers.
• Grade 2 - The cancer cells look more abnormal and grow slightly more quickly than grade 1.
• Grade 3 - The cancer cells tend to grow more quickly, look very abnormal (are ‘poorly differentiated’) and are more likely to spread.

Invasive bladder cancers are usually grade 2 or grade 3.

Another grading system classes invasive bladder cancer as either ‘low grade’ or ‘high grade’. Low-grade cancers are slower growing and less likely to spread than high-grade bladder cancers.

Staging

A cancer’s stage describes its size and whether it has spread. Once your doctors know the stage of the cancer, they can decide on the most appropriate treatment for you. A common staging system uses numbers to indicate the stage of the cancer.

Stage 0a

There is a small area of cancer only in the bladder lining.

Stage 0is or CIS (carcinoma in situ)

This is sometimes described as a flat tumour. The cancer cells are confined to the inside layer of the lining of the bladder.

Stage 1

The cancer has grown into the layer of connective tissue beneath the bladder lining.

Stage 2

The cancer has grown into the muscle of the bladder wall under the connective tissue layer.

Stage 3

The cancer has grown through the muscle of the bladder and into the fat layer surrounding it. It may have spread to the prostate, womb or vagina.

Stage 4

The cancer has spread to the wall of the abdomen or pelvis, the lymph nodes or to other parts of the body. If bladder cancer spreads to other parts of the body, it will most likely go to the lungs, liver or bones.

 

Others terms used

Early, superficial or non-muscle invasive bladder cancer refers to stage 0a, stage 0is (CIS) and stage 1 bladder cancers.

Invasive bladder cancer refers to stage 2 and stage 3 bladder cancers.

Advanced bladder cancer refers to stage 4 bladder cancer.

Metastatic bladder cancer means the cancer has spread to other parts of the body.

Another commonly used staging system for bladder cancer is called the TNM system:

• T is the size of the tumour (cancer).
• N is whether it has spread to the nearby lymph nodes (sometimes called glands).
• M is whether the cancer has spread to other parts of the body (metastases).