Breast cancer is a prevalent disease among women. A survey indicates that 30% of cancer diagnoses in women are breast cancer cases. While it primarily affects women aged 50 and older, it can also impact those under the age of 50.
What Causes Breast Cancer?
The primary cause of breast cancer is the unchecked growth of abnormal breast cells. This proliferation leads to the formation of tumors. Women who are breastfeeding are particularly susceptible, as cancerous cells typically develop in the lobules—glands responsible for milk production—or in the ducts that transport milk to the nipple. If not detected early, these tumor cells can spread to other areas of the body.
Several significant factors that may contribute to breast cancer include obesity, excessive alcohol consumption, and frequent radiation exposure. Additionally, advancing age and a family history of breast cancer can also elevate the risk of developing the disease.
Symptoms of Breast Cancer
In the early stages of breast cancer, there are typically no noticeable symptoms. However, as the disease progresses to a more advanced stage, certain symptoms may become apparent. The primary symptoms are listed below:
- An abnormal breast thickening or a lump, mostly painless
- Change in the shape and size or appearance of the breast
- Appearance of a dimple, and redness surrounding the breast
- Sometimes there are changes in appearance in a nipple and the surrounding skin
- Bloody discharge from the nipple
Types of Breast Cancer
Based on the location of the cancerous tumor in the breast, its growth rate, and its typical characteristics, there are two main types of breast cancer, each with various subtypes that reflect their nature. These types of breast cancer are discussed below.
Invasive Breast Cancer
When breast cancer spreads into the surrounding breast tissues, it is classified as invasive breast cancer. This type can be further divided into various subtypes. One example is invasive ductal carcinoma, which begins in the milk ducts that transport milk from the lobules to the nipple; this subtype accounts for about 80% of all breast cancers. Another subtype is invasive lobular carcinoma, which originates in the lobules and represents approximately 10% of breast cancer cases. Additionally, there are triple-negative and triple-positive breast cancers, which test negative and positive, respectively, for estrogen and progesterone receptors. Inflammatory breast cancer is another subtype of invasive breast cancer.
Non-Invasive Breast Cancer
The other primary type of breast cancer is non-invasive breast cancer, which typically does not spread beyond its point of origin. Non-invasive breast cancer is also known as precancers. This category includes two main subtypes: ductal carcinoma in situ, which remains confined to the milk ducts where it originated, and lobular carcinoma in situ, which is another form of non-invasive breast cancer.
Stages of Breast Cancer
Based on diagnostic reports and physical factors such as the type of breast cancer, tumor location, size, and extent of spread, physicians have classified breast cancer into five distinct stages to facilitate treatment.
- Stage 0: This stage is characterized by cancer that remains confined to the ducts and does not spread to other parts of the breast.
- Stage I: At this stage, cancerous cells begin to spread into nearby breast tissue.
- Stage II: In this stage, tumors of varying sizes may be observed, which may or may not involve nearby lymph nodes.
- Stage III: Known as locally advanced breast cancer, Stage III can directly impact nearby tissues and lymph nodes.
- Stage IV: This final stage of breast cancer indicates that the cancer has spread from the breast to other areas, such as the bones, liver, or even the brain.
Treatment of Breast Cancer
Based on the stage of breast cancer, doctors determine the most appropriate course of action. This approach may involve surgery, which can include mastectomy, lumpectomy, and breast reconstruction. In some cases, surgery is combined with treatments such as chemotherapy, radiation therapy, immunotherapy, hormone therapy, or targeted therapy.