The stages of breast cancer are determined by the size of the tumor, whether the cancer affects the lymph nodes or not, whether the cancer is invasive or non invasive and whether it has spread to areas other than the breast.
It is important to understand the stages of breast cancer in order to understand chances of survival, kind of treatment to be obtained and understand the prognosis or the outcome of the cancer.
The stages of breast cancer are standardized so that healthcare providers the world over are able to understand the nature and extent of a given person’s disease; which are 0 through IV stages.
According to the National Breast Cancer website, those who are at the 0 stage have 100% chance of 5 year survival; at Stage I that rate is 98%, at Stage II the five year survival rate drops to 80%, at stage III it is between 56% and 49% and at stage IV the five year survival rate is only 16%. The different stages of cancer correspond to the following situations:
Stage 0 (Carcinoma in Situ): This is breast cancer at the earliest stage, when the abnormal cells have not spread outside the lobules of the ducts which produce milk during lactation.
This stage could signify the woman’s risk of developing cancer or it signifies a very early stage wherein it is easy to treat the cancer before it starts to spread and go on to the next stage.
Stage I: At this stage the size of the tumor is two centimeters or less and has not yet spread to areas other than the breast or the surrounding lymph nodes.
Stage II (A & B): At the stage of breast cancer II A the cancer is about an inch in size and has spread to the lymph nodes situated in the underarm. If the tumor is between 2 and 5 centimeters but hasn’t spread to the lymph nodes, it is still classified as being Stage II A.
At Stage II B the tumor is between 2 and 5 centimeters in size but has spread to three lymph nodes. If the tumor is larger than 5 centimeters but has not spread to the lymph nodes, then this is still classified as Stage II B.
Stage III (A & B): At stage III A, the cancer is between 2 and 5 centimeters in size and has also spread to the nine auxiliary lymph nodes. If the cancer has spread to areas such as the ribs, chest wall, skin of the breast, or the lymph nodes of the chest wall or collar bone.
Stage IV: This is the last of the stages of breast cancer, when the cancer has spread to surrounding areas such as the lungs, the liver, the brain, the skeletal system or the collar bone lymph nodes.
It is important to understand the different stages of breast cancer so as to be able to make informed decisions about treatment, and form opinions and expectations about survival.