Image acquired with fluorescence microscopy showing stress fibers (red) and microtubules (green) in human breast cancer cells (nuclei, blue). These cytoskeletal proteins are essential for survival and cellular processes in both normal as well as cancer cells. However, these mechanisms can be altered to promote cancer cell growth and invasive capabilities.
Photo: National Cancer Institute
Cancer occurs when cells something causes the cells in your body to keep multiplying. This uncontrolled growth can lead to overcrowding of cells, which may form lumps of tissue known as tumors.
When the cancer develops in the breast cells, it’s known as breast cancer. The cancer can form in different areas of the breast, including:
These cancerous cells can spread if they get into the blood or lymph vessels, providing a pathway to other healthy cells of the body. When cancer cells travel and spread to other parts of your body, the cancer is called metastatic.
Early detection is key when it comes to treating any type of cancer.
While breast cancer may not cause any symptoms in its early stages, the most common sign is a lump in the breast that was not there before. Not all lumps are cancers, but a hard, painless mass of tissue that has irregular edges is likely to be cancer.
The signs: The symptoms of breast cancer can vary for different people. The most common symptoms of breast cancer include:
Follow through: While these signs can be warning signs of breast cancer, they can also be caused by a non-cancerous condition like a cyst.
If you experience any of the symptoms above, you need to see a doctor who will conduct the appropriate tests to check whether you have breast cancer.
There are several types of breast cancer, which are typically categorized by where the cancer originates in the breast.
In general, breast cancers are broken down into 2 main categories:
An invasive cancer is one that has spread into the surrounding breast tissue, whereas non-invasive cancer has not spread beyond the site of origin.
Ductal carcinoma in situ (DCIS) is a noninvasive cancer accounting for nearly 1 in 5 new breast cancer cases.
With DCIS, the breast cancer is confined to the walls of the ducts and has not spread to nearby breast tissue. Nearly all women detected at this early stage can be cured of breast cancer with effective treatment.
However, DCIS can sometimes become invasive if left untreated.
Lobular carcinoma in situ (LCIS) refers to cells growing in the lining of milk-producing glands called lobules. Like DCIS, the cancerous cells in lobular carcinoma in situ haven’t invaded the nearby breast tissue.
The types of LCIS include:
While LCIS does not spread beyond the lobule even if it isn’t treated, it does run the risk of developing into invasive breast cancer.
Invasive ductal carcinoma starts in the milk duct in the breast but can spread into nearby tissues by breaking through the duct wall.
According to the American Cancer Society, about 8 in 10 invasive breast cancers are invasive ductal carcinomas — making it the most common type of breast cancer.
Triple-negative breast cancer refers to cancers satisfying specific conditions and accounts for nearly 10 to 15 percent of all breast cancers, according to the American Cancer Society.
To be diagnosed with triple-negative breast cancer, a tumor must:
Because triple-negative breast cancers lack the estrogen and progesterone receptors and don’t make too much of the HER2 protein, they don’t respond to hormonal therapy.
Triple-negative breast cancers tend to grow and spread more quickly and are more likely to return after treatment compared to other types of breast cancer.
Inflammatory breast cancer (IBC) is a rare but aggressive type of breast cancer – accounting for only 1 to 5 percent of all breast cancer but almost always detected at an advanced stage.
Inflammatory breast cancer is a type of invasive ductal carcinoma but with different symptoms and treatments. It occurs when cancer cells block the lymph vessels in the breast, causing the breast to look red, swollen, and feel warmer and heavier.
The survival rates for inflammatory breast cancer are not as high as other types of breast cancer, particularly because IBC has already metastasized by the time of diagnosis in about 1 in 3 cases.
Angiosarcoma is cancer that starts in the cells lining the blood or lymph vessels in the breast and accounts for less than 1 percent of all breast cancers.
The condition can cause skin changes in the breast, leading to the appearance of purple-colored nodules.
The most common types of breast cancer are the same for both men and women, and the symptoms that they experience are typically identical.
A healthier lifestyle, including a healthy weight and limiting alcohol consumption, seems to lower the risk of developing breast cancer in both women and men.
By the numbers: Male breast cancer is rare, accounting for nearly 1 percent of all breast cancer cases diagnosed in the U.S. However, breast cancer is often diagnosed late in men, leading to lower survival rates, ranging from 40 to 65 percent.
The ACS reports that the risk of breast cancer is about 70 times less among Black men compared to Black women. This risk is about 100 times lower in White men compared to White women.
The process of staging breast cancer involves determining if the cancer has spread and to what extent.
According to the ACS, the following factors are considered when staging breast cancer:
Based on these, breast cancer is given one of five main stages.
The cancer is in situ, that is, the cells remain confined in their site of origin and have not spread to any nearby tissue.
The breast cancer is small and is confined only to the breast tissue, or in the lymph nodes close to the breast.
The breast cancer is either in the breast, in the nearby lymph nodes, or both.
The cancer has spread from the breast to lymph nodes close to the breast or to the skin of the breast.
The breast cancer has metastasized — meaning that the cancer has spread to other parts of the body. It is also known as advanced or metastatic breast cancer.
If you experience a lump in your breast or any other symptom of breast cancer, your doctor will typically conduct a physical breast exam along with screening tests to determine your condition.
A breast cancer diagnosis can include the following tests:
A biopsy is the only way to know for sure if you have breast cancer. If the sample tests positive for cancer, your doctor will recommend the next steps in treatment.
Treatment for breast cancer depends on a variety of factors, including:
Surgery is the most common treatment for breast cancer and is often a part of treatment to remove as much of the cancer as possible. Other treatment options include chemotherapy, hormone therapy, and radiation therapy.
Breast cancer surgery is performed to remove as much of the cancerous tissue from the breast as possible.
There are multiple types of surgery for breast cancer depending upon the conditions, including:
While surgery is effective in curing localized breast cancer, it is unlikely to cure cancer that has spread to other parts of the body.
Radiation therapy uses high-energy radiation to destroy cancer cells. The process is often conducted after surgery when treating the early stages of breast cancer.
There are two main types of radiation therapy used to treat breast cancer:
Radiation therapy for breast cancer is typically performed after a lumpectomy or mastectomy to remove any cancer cells that may have been left behind during the surgery.
Chemotherapy uses anti-cancer drugs such as anthracyclines and taxanes that may be given intravenously or orally. It is typically used in conjunction with other forms of treatment, typically surgery.
Side effects: Chemo can also lead to a number of side effects, the most common of which include:
While these side effects typically go away after the treatment is finished, you should discuss any concerns with your doctor if you are considering the treatment.
Some breast cancers are affected by hormones such as estrogen and progesterone. According to the American Cancer Society, 2 out of 3 breast cancer are hormone-receptor positive — meaning that they need a certain hormone to grow.
Hormone therapy may help slow down or stop the growth of the tumor. The treatment is typically performed for at least 5 years.
Immunotherapy boosts your body’s own immune system to fight off cancer cells more effectively. It does so with the use of immunotherapy drugs such as monoclonal antibodies checkpoint inhibitors.
Cancer cells can also be specifically destroyed by targeted drug therapy, which involves the use of medications that attack mutations within cancer cells.
Some of the most common drugs used to treat breast cancer include:
You should talk to your doctor about the potential side effects of any of these medications before deciding on the appropriate treatment.
The ACS reports that white women are at a slightly higher risk of developing breast cancer compared to African American women. However, the difference has been reducing in recent years.
Female breast cancer incidence (2015–2019) and mortality (2016–2020) rates by race/ethnicity in the United States. Data: American Cancer Society Journals
Graph by The Lamen
Studies have also shown that race, ethnicity, and socioeconomic status are integral in determining the detection and effective treatment of breast cancer.
Survival rates of cancers are estimates, and the survival rate of breast cancer depends on a variety of factors.
These factors include:
By the numbers: The 5-year survival rate for women in the United States with non-metastatic invasive breast cancer is 91 percent. The survival rate decreases to 85 percent at the 10-year mark.
Additionally, the mortality rate for Black women (28.4 per 100,000 women) is significantly higher than that of White, Hispanic, and Asian women.
Here are some statistics for breast cancer from the American Cancer Society:
Breast cancer is often a life-changing event, and one cannot anticipate the condition under normal circumstances. If you’ve been diagnosed with breast cancer, you may feel upset, shocked, and frightened.
While many women can get treated when breast cancer is detected early, they might worry about it coming back or even affecting their lifestyle.
Even if you have completed your breast cancer treatment, you will typically still require follow-up checkups involving physical exams and mammograms.
To cope with the changes in life during this period, you should:
With coping techniques and treatment, even women who have been detected with an advanced breast cancer may continue to live for several years.
Cancer is caused when cells grow uncontrollably, often due to mutations that inactivate the genes that suppress cell proliferation. As such, some risk factors such as genetics cannot be avoided, certain lifestyle changes have been shown to decrease the risk of developing breast cancer.
While these factors may reduce the probability, they do not ensure that you will not develop cancer. However, they can help with increasing the chances of successful treatment and survival.