Stages of kidney cancer

The stage of a cancer tells the doctor how far 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. The number stages (usually 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 for nodes and the M for metastases (the doctors' word for cancer spread). 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 more 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 kidney capsule, to a major vein, the adrenal gland or other tissues immediately surrounding the kidney
• T4 - the cancer has spread further than the tissues immediately surrounding 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. This is being introduced because it is important for surgeons. If you have a smaller tumour, it may be possible to remove just the cancer and leave the rest of the kidney behind (nephron sparing surgery).

These tell the doctor if 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'. If you have cancer in your lymph nodes, then your kidney cancer has begun to spread. Your doctor may want you to have further treatment after your surgery. Look at which treatment? in this section for more information.

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, then you have advanced kidney cancer. Look at the CancerHelp UK section on treating advanced kidney cancer for more information.

By combining the T, N & M stagings 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

Doctors tend to use Roman numerals for writing down cancer stage. So you may see stage written as I, II, III, or IV.

The grade of your cancer is decided by the appearance of the cancer cells under the microscope. The more they 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. Look at which treatment for kidney cancer? in this section of CancerHelp UK for more information.