Staging of Cancer
What is stage or staging in Cancer?
Every cancer that is diagnosed is given a stage. Stage is based on the type of cancer that is found, its spread to surroundings structures and organs and spread to distant parts of the body. The stage helps the doctor to decide on the best treatment.
What are the types of stages in Cancer?
Stages can be of two types. One is giving a number from 1 to 4, ie stage 1, stage 2 etc. This can be called the number staging system. The other one is TNM staging system.
TNM stands for Tumour, Node, Metastases. T stage is given a number from T1 to T4 depending on the size of the cancer or involvement of surrounding organs. N stage depends on whether the lymph nodes close to the cancer are involved with cancer or not. N stage can be from N1 to N3. M stage is whether there is distant spread of cancer or not. It is denoted as M0 or M1.
How many stages are there?
Usually each cancer is divided into 4 stages. Stage 1 is when cancer is in an early stage and stage 4 is when the cancer has spread to distant parts of the body. A high proportion of stage 1 cancers are curable where as stage 4 cancers are not curable. Cure means that the cancer goes with treatment and never comes back. Stages 2 and 3 are in between.
How is a stage of cancer determined?
Cancer is given based on x-ray or scans. This is called as radiological staging. A stage can be given based on the examination by the doctor. This is called as clinical staging. A stage is giving after surgery is done to remove the cancer. This is called as pathological staging.
Does stage of Cancer change over time?
Yes, the stage of the cancer can change over time. For example, at the time of diagnosis the cancer can be staged as 3. After a few months, the cancer spreads to other organs such as liver or bones and this increases the stage from 3 to 4. At this point it becomes incurable. Stages 4 cancers may not be curable but still treatable.
What is stage 0?
Some cancers are very early, that is they are in a pre-cancerous stage and have not yet got the capacity to spread to other parts of the body. They are sometimes given a stage 0.