Health
Fact-checked

At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

What are the Stages of Breast Cancer Progression?

Dorothy Bland
Dorothy Bland

Breast cancer is generally broken up into five major stages, ranging from stage 0 to stage IV. This method of tracking breast cancer progression functions as a simplified way of categorizing and organizing the disease. The classification gives medical professionals and breast cancer patients a means of understanding the characteristics that breast cancer typically displays at each stage. For each stage, cancer is grouped by tumor size and how far the cancer has spread within the body.

The first stage in breast cancer progression is stage 0, or carcinoma in-situ, and occurs when abnormal cells grow within the milk duct or lobule of the breast. At this stage, the cancer is noninvasive and has not spread to the lymph nodes. Generally, this early stage of cancer cannot be detected through a breast exam and is more likely to be found when receiving a mammogram. If treatment or detection is delayed, the cancer can advance through the walls of the duct.

Mammograms are performed to detect the presence of breast cancer.
Mammograms are performed to detect the presence of breast cancer.

Although stage 0 may be considered cancer, it is often used to describe a precancerous condition; stage I is often considered the first actual cancer stage. Together, stages I to IV of breast cancer progression all refer to invasive forms of cancer. In other words, the cancer cells have the ability to invade into surrounding normal tissue.

Both stage I and stage II breast cancers are still confined to the breast tissue. A stage I, cancer prognosis generally describes the formation of a small tumor measuring less than 1 inch (around 2 centimeters). By the time of a stage II breast cancer progression, however, the tumor is beginning to spread into a few of the axillary, or underarm, lymph nodes.

Most breast cancers start in a milk duct or lobule.
Most breast cancers start in a milk duct or lobule.

Phase II breast cancer is further broken down into two subclasses, stage IIA and stage IIB. Generally, stage IIA refers to a cancerous growth smaller than 1 inch (around 2 centimeters) that is also affecting the lymph nodes. It may also refer to a tumor of up to 2 inches (around 5 centimeters) which has not yet spread into the lymph nodes. Stage IIB, is more advanced than stage IIA and is distinguished by tumors measuring between 1 to 2 inches (roughly 2 to 5 centimeters) that have begun dispersing into the underarm lymph nodes. The stage IIB diagnosis can also apply to tumors that are greater than this size but have not yet extended down into the underarm lymph nodes.

It's important for women to regularly conduct self breast exams.
It's important for women to regularly conduct self breast exams.

Once breast cancer progresses to stage III or later, the cancerous tumor is advancing outside of the local area of the breast. At stage III, tumors are larger than 2 inches (about 5 centimeters) and can be further broken up as stage IIIA, stage IIIB and stage IIIC. Stage IIIA describes cancer cells that are in the lymph nodes, but a tumor is not found in the breast. Regardless of the tumor size in the breast when cancerous cells are joining in the lymph nodes, the condition is also generally described as stage IIIA. The diagnosis of stage IIIB typically indicates that a cancer has spread to the skin of the breast or other nearby tissues, while a stage IIIC cancer is spreading through the lymph nodes into the collarbone and the breastbone.

A breast cancer prognosis is much better when the malignancy is detected early.
A breast cancer prognosis is much better when the malignancy is detected early.

At stage IV, the breast cancer progression is considered metastatic. This indicates that the cancer is spreading through the lymphatic system or the blood into distant parts of the body. By the time cancer has reached this stage, it has the capability to spread to practically anywhere in the body. Organs commonly affected by the advanced of breast cancer include the brain, bones or lungs.

In some cases, advanced breast cancer metastasizes and spreads to the brain or another organ that is not in close proximity.
In some cases, advanced breast cancer metastasizes and spreads to the brain or another organ that is not in close proximity.

Understanding breast cancer progression can help patients better appreciate how far their condition has advanced. From a medical standpoint, this information provides a basis for deciding how aggressively to treat the disease. Although survival rates for breast cancer does go down once the cancer has spread outside of the breast, this does not mean that treatment will be unsuccessful. By combining different treatment options such as chemotherapy, radiation therapy and surgical removal of the tumor, breast cancer sufferers can improve their chances of surviving malignant breast cancer.

Discuss this Article

Post your comments
Login:
Forgot password?
Register:
    • Mammograms are performed to detect the presence of breast cancer.
      By: Tyler Olson
      Mammograms are performed to detect the presence of breast cancer.
    • Most breast cancers start in a milk duct or lobule.
      By: Balint Radu
      Most breast cancers start in a milk duct or lobule.
    • It's important for women to regularly conduct self breast exams.
      By: 9nong
      It's important for women to regularly conduct self breast exams.
    • A breast cancer prognosis is much better when the malignancy is detected early.
      By: edbockstock
      A breast cancer prognosis is much better when the malignancy is detected early.
    • In some cases, advanced breast cancer metastasizes and spreads to the brain or another organ that is not in close proximity.
      By: WavebreakmediaMicro
      In some cases, advanced breast cancer metastasizes and spreads to the brain or another organ that is not in close proximity.
    • A patient diagnosed with stage four breast cancer generally has a poor prognosis.
      By: Lisa F. Young
      A patient diagnosed with stage four breast cancer generally has a poor prognosis.