How Does Cancer Staging Work? 

Cancer staging refers to the diagnosis and prognosis of a cancer. In other words, staging relates to how far the cancer has spread and at what stage it is for a patient. Cancer staging is crucial in determining a patient’s journey - it can help resolve what treatment is best, as well as what the survival rate might be. 

A doctor will do various tests, such as x-rays, scans, blood tests and any other clinical or laboratory tests to determine the stage of a particular cancer. Staging can tell where the tumour might be, how big it is, if it has spread locally or whether it might have spread elsewhere in the body. 

What Is Cancer Staging and Why Is it Important?

Staging is a term that describes how far cancer in a body has spread or grown. It is important to know the stage of cancer, because this affects how a patient will be treated alongside the prognosis of the cancer. This means how serious the cancer is - in terms of what a possible cure or survival is. 

Cancer staging is also critical to determine what the best treatment plan is for a specific cancer, and whether there are clinical trials that could assist a patient in their journey. 

How Many Stages of Cancer Are There?

There are various levels when it comes to cancer staging. The stage assigned to a cancer will indicate the severity of it. 

The simplest staging system is as follows: 

• Stage 0: This means that abnormal cells have been identified but it is not yet cancerous. Also known as “carcinoma in situ”, the cells may become cancerous but the important point here is that the abnormality has been detected very early on and the options for treatment and cure are very high. 

Stages 1, 2 and 3, meanwhile, indicate there is a presence of cancer. In such stages, the higher the number, the bigger the size of the tumour and the more it may have spread to surrounding tissue.

• Stage 1: The cancer is localised and has not yet spread beyond its primary site.

• Stage 2: The cancer is still localised, but there is more advanced growth into surrounding tissue. It is also referred to as early locally advanced cancer. 

• Stage 3: The cancer has advanced into the lymph nodes. 

• Stage 4: The cancer has spread beyond the primary site and lymph nodes, to other parts of the body and is described as advanced or metastatic cancer. 

A further Stage 5 is described for a cancer called Wilms tumour, which is a cancer of the kidneys that occurs in children. In Stage 5 of Wilms tumour, the cancer has been found in both of the kidneys. 

The TMN System 

The most common staging system used by doctors is known as the TMN system and provides more details than the above method. TMN stands for: 

• T: The size of the primary (main) tumour. 
• N: How many lymph nodes have been affected by the cancer. 
• M: Whether the cancer has spread beyond the primary site. When cancer has spread beyond this primary site, to other parts of the body, it is said to have “metastasised”. 

Numbers are given after each letter, to describe in more detail what the stage of the cancer is.  

For example T1, T2, T3 describes different sizes or extent of the tumour. The higher the number, the larger the tumour or the more it has grown into surrounding tissue. 

N1, N2, N3, etc – describes how many lymph nodes have been detected with cancer. 

MX means metastases cannot be measured; M0 means there is no cancer spread beyond the primary site, and M1 means the cancer has indeed spread beyond the primary site to other areas in the body.  

If the cancer has been staged clinically, a “c” will be placed before the lettering. If the description is determined based on pathology, in other words, through laboratory and other testing, a “p” will be placed before the letters. 

An “x” means it cannot or has not been determined. If the cancer is being staged after treatment, a “y” will be added to the lettering or an “r” if there is re-staging after a cancer has recurred. 

Other Staging Systems 

 Another simple staging system is descriptive and is described as follows: 

• In situ: Here, as described above, abnormal cells have been detected but there is no spread to surrounding tissue. Technically, it is not considered as cancer but may become cancerous later.  
• Localised: The tumour is only at a primary site and has not spread beyond this. 
• Regional: Here the cancer has now spread to tissues, organs or lymph nodes nearby the primary tumour. 
• Distant: The cancer has spread beyond the primary site to other parts of the body. 

Some specific cancers have special grading systems. For example, the Gleason scoring system is used for prostate cancer and the Nottingham grading system is often used for breast cancer.  

Gynaecological and childhood cancers also often have their own specific grading systems, but they all follow similar principles as those described above. 

What to Do When You Have Been Diagnosed with Cancer? 

Getting a cancer diagnosis can be overwhelming and create a lot of fear and confusion. You will no doubt have many questions you need answering as you come to terms with your diagnosis and what it means for you and/or your family.  

It is important to speak to your doctor to find out what the various options are at your disposal. Counselling might also be important to help you cope with this diagnosis. 

Similarly, getting a second opinion or further assistance might also be a route you’re considering. GlobMed have worked with both NHS and private health care services for many years. We can help support you navigate health care systems through your diagnosis journey.