Stages of kidney cancer

The stage of a cancer means how big the cancer is and whether it has spread. The tests and scans you have to diagnose your cancer will give some information about the stage. It is important because treatment is often decided according to the stage of a cancer. There are two ways of writing cancer stage. These are the number stages (usually from stage 1 to stage 4) and the TNM system.

The TNM system is a staging system that is common to all cancers. The T stands for tumour. The N stands for lymph nodes and the M for metastases (meaning whether the cancer has spread to other parts of the body). With this combination of letters and numbers, doctors can accurately describe the size of your cancer and whether it has spread to lymph nodes or elsewhere in the body. There is information about the TNM staging system in the stages of a cancer section.

The T stages are

• T0 – there is no evidence of a primary tumour in the kidney
• T1 – the tumour is no more than 7cm across and is completely inside the kidney
• T2 – the tumour is more than 7cm across, but is still completely inside the kidney
• T3 – the cancer has spread through the outer covering of the kidney (the capsule), to a major vein, the adrenal gland or other tissues around the kidney
• T4 – the cancer has spread further than the tissues around the kidney

You may hear your doctor talk about T1a or T1b. T1a means you have a tumour that is less than 4cm across. T1b means the kidney tumour is between 4 and 7cm across.

The N stages mean whether the cancer has spread to your lymph nodes. There are three lymph node stages in kidney cancer. These are

• N0 – No cancer in any lymph nodes
• N1 – Cancer spread to one nearby lymph node only
• N2 – Cancer spread to more than one nearby lymph node

Doctors often call lymph nodes that contain cancer positive lymph nodes.

As with most cancers, there are two stages for metastases (or cancer spread). Either the cancer has spread (M1) or it hasn't (M0). If your cancer has spread, you have advanced kidney cancer. Look at the section about treating advanced kidney cancer for more information.

By combining the T, N and M stages of your tumour, your doctor will give it an overall stage. This is important for deciding which treatment is best for you. There are 4 stages for kidney cancer. They are

• Stage 1 – The cancer is less than 7cm across and is completely inside the kidney

• Stage 2 – The cancer is more than 7cm across but is still completely inside the kidney

• Stage 3 – The cancer has grown into the adrenal gland, or one of the major veins nearby. There is no more than one nearby lymph node containing cancer cells

• Stage 4 – The cancer has grown into the surrounding tissues and there is more than one lymph node containing cancer cells OR the cancer has spread to another part of the body

The grade of your cancer is decided by the appearance of the cancer cells under the microscope. The kidney cancer grading system is called the Fuhrman system. The more the cells look like normal kidney cells, the lower the grade of your cancer. The more abnormal (and so less like normal kidney cells) the cancer cells look, the higher the grade of your cancer. Generally speaking, low grade cancers tend to grow more slowly and are less likely to spread than high grade cancers.

The main factor for deciding which treatment is best for you is whether your cancer has spread away from the kidney or not. For more information look at the page about types of treatment for kidney cancer in this section.