If you have cancer, the doctors will want to know how much the growth can grow.

Stages of cancer is a ranking the doctors offer based on tests to assess the severity of the cancer. Laboratory tests are also used to determine how much cancer has spread out of the body inside the tissue extracted. Imaging techniques can also be used to stage cancer. Imaging tests do pictures of the body's inside. The images help your doctors to see where the cancer is developing and spreading.

More recently, knowledge is being used to stage other cancers other than where and how much cancer is found in your body. These details may include results of blood tests, results of histological (cell) tests, and risk factors. A risk factor is something that raises the likelihood of a health occurrence, such as the rapid growth of cancer. Where and how much cancer is still key to cancer stages in your body, though.

Staging cancer is critical for many reasons. Often your doctors will determine if you need further cancer-based tests. The stage of cancer is also one of the criteria used by doctors to determine a prognosis. Prognosis is a scientific term for the pattern and outcome predicted of a disease. Most importantly, the stage of cancer is a consideration the doctors use to determine which therapies are best for you. The cancer stage is used in research to evaluate treatment outcomes across patient groups, to compare results between treatment centres, and to plan study studies.

Cancer is often staged twice. Before treatment, the first assessment is performed and is called the clinical level. After diagnosis, the second level is performed after treatments such as Surgery and is called the pathologic stage. The pathologic stage of the cancer is more specific.

How many stages of cancer are there?

• Stage 0 or carcinoma in situ. In situ carcinoma is known to be pre-malignant, or pre-cancer. Abnormal cells can only be identified in the first layer of cells at the location where the changes first began. Deeper tissues are not infiltrated by cells. Over time, these cells may become cancerous, so it is important to find them and treat them before this happens. This stage is not used in most forms of cancer.
• Stage I. Cancer only exists in the cells where it began first, and the region is small. This is deemed to be early and most curable.
• Stage II. Cancer is inside the organ where it began first. It may be slightly larger than stage I, and/or spread to neighbouring lymph nodes.
• Stage III. Cancer is in the organ where it initially began. It may be larger than stage II and may have spread to neighbouring lymph nodes and/or other tissues, organs, or structures close by.
• Stage IV. Cancer has spread (metastasized) to organs in other areas of the body. There may be cancer-indifferent organs, but it is still the same form of cancer as it started at first. For example, Colon Cancer that spreads to the liver is not liver cancer, it is cancer of the stage IV colon with liver metastases. The cancer cells in the liver look like Colon Cancer cells and are classified as Colon Cancer.

Recurrent cancer has (recurred) returned since it was treated. It returns to the same place or another part of the body.

Understanding the 4 Stages of Cancer

Typically, higher numbers mean more widespread disease, greater tumour size and/or cancer spread beyond the organ where it first grew. Higher grade and stage cancers tend to be more difficult to cure and also need heavy treatments. When assigned a stage and provided care, the stage is never changed. A stage I cancer of the cervix, for example, is treated. The same cancer has spread two years later and is now contained in the heart. It is not stage IV now but stage I, with recurrence to the lung.

The main thing about staging is that it decides the correct treatment, lets healthcare professionals make a prognosis, and enables the outcomes of the procedure to be compared. The grade and stage of cancer can be extremely complex and confusing. Be sure to ask your healthcare professional to explain this cancer information to you in a manner you would understand.