Types of Breast Cancer

Types Of Breast Cancer

Ductal Carcinoma In Situ (DCIS) is non-invasive breast cancer. Ductal means that the cancer starts inside the milk ducts, carcinoma refers to any cancer that begins in the skin or other tissues (including breast tissue) that cover or line the internal organs, and in situ means "in its original place." DCIS is called "non-invasive" because it hasn’t spread beyond the milk duct into any normal surrounding breast tissue. DCIS isn’t life-threatening, but having DCIS can increase the risk of developing an invasive breast cancer later on.

When you have had DCIS, you are at higher risk for the cancer coming back or for developing a new breast cancer than a person who has never had breast cancer before. Most recurrences happen within the 5 to 10 years after initial diagnosis. The chances of a recurrence are under 30%.

Women who have breast-conserving surgery (lumpectomy) for DCIS without radiation therapy have about a 25% to 30% chance of having a recurrence at some point in the future. Including radiation therapy in the treatment plan after surgery drops the risk of recurrence to about 15%. Learn what additional steps you can take to lower your risk of a new breast cancer diagnosis or a recurrence in the Lower Your Risk section. If breast cancer does come back after earlier DCIS treatment, the recurrence is non-invasive (DCIS again) about half the time and invasive about half the time. (DCIS itself is NOT invasive.)

Invasive Ductal Carcinoma (IDC)

Invasive ductal carcinoma (IDC), sometimes called infiltrating ductal carcinoma, is the most common type of breast cancer. About 80% of all breast cancers are invasive ductal carcinomas.

Invasive means that the cancer has “invaded” or spread to the surrounding breast tissues. Ductal means that the cancer began in the milk ducts, which are the “pipes” that carry milk from the milk-producing lobules to the nipple. Carcinoma refers to any cancer that begins in the skin or other tissues that cover internal organs — such as breast tissue. All together, “invasive ductal carcinoma” refers to cancer that has broken through the wall of the milk duct and begun to invade the tissues of the breast. Over time, invasive ductal carcinoma can spread to the lymph nodes and possibly to other areas of the body.

There are various other subtypes of IDC like IDC Tubular Carcinoma, Medullary Carcinoma, Mucinous Carcinoma , Papillary Carcinoma and Cribriform Carcinoma.

Although invasive ductal carcinoma can affect women at any age, it is more common as women grow older. Invasive ductal carcinoma also affects men.

Invasive Lobular Carcinoma (ILC)

Invasive lobular carcinoma (ILC), sometimes called infiltrating lobular carcinoma, is the second most common type of breast cancer after invasive ductal carcinoma (cancer that begins in the milk-carrying ducts and spreads beyond it). About 10% of all invasive breast cancers are invasive lobular carcinomas. (About 80% are invasive ductal carcinomas.)

Invasive means that the cancer has “invaded” or spread to the surrounding breast tissues. Lobular means that the cancer began in the milk-producing lobules, which empty out into the ducts that carry milk to the nipple. Carcinoma refers to any cancer that begins in the skin or other tissues that cover internal organs — such as breast tissue. All together, “invasive lobular carcinoma” refers to cancer that has broken through the wall of the lobule and begun to invade the tissues of the breast. Over time, invasive lobular carcinoma can spread to the lymph nodes and possibly to other areas of the body.

Although invasive lobular carcinoma can affect women at any age, it is more common as women grow older. About two-thirds of women are 55 or older when they are diagnosed with an invasive breast cancer. ILC tends to occur later in life than invasive ductal carcinoma — the early 60s as opposed to the mid- to late 50s.

Some research has suggested that the use of hormone replacement therapy during and after menopause can increase the risk of ILC.

Inflammatory Breast Cancer

Inflammatory breast cancer (IBC) is a rare and aggressive form of breast cancer. About 1% of all breast cancer cases in India are inflammatory breast cancers.

Inflammatory breast cancer usually starts with the reddening and swelling of the breast instead of a distinct lump. IBC tends to grow and spread quickly, with symptoms worsening within days or even hours. It usually mimics infection, abscess and acute inflammatory pathology and is usually misdiagnosed initially.  It’s important to recognize symptoms and seek prompt treatment. Although inflammatory breast cancer is a serious diagnosis, keep in mind that treatments today are better at controlling the disease than they used to be.

IBC is seen in male breasts too.

Lobular Carcinoma In Situ (LCIS)

Lobular carcinoma in situ (LCIS) is an area (or areas) of abnormal cell growth that increases a person’s risk of developing invasive breast cancer later on in life. Lobular means that the abnormal cells start growing in the lobules, the milk-producing glands at the end of breast ducts. Carcinoma refers to any cancer that begins in the skin or other tissues that cover internal organs — such as breast tissue. In situ or “in its original place” means that the abnormal growth remains inside the lobule and does not spread to surrounding tissues. People diagnosed with LCIS tend to have more than one lobule affected.

Despite the fact that its name includes the term “carcinoma,” LCIS is not a true breast cancer. Rather, LCIS is an indication that a person is at higher-than-average risk for getting breast cancer at some point in the future. For this reason, some experts prefer the term “lobular neoplasia” instead of “lobular carcinoma.” A neoplasia is a collection of abnormal cells.

LCIS is usually diagnosed before menopause, most often between the ages of 40 and 50. Less than 10% of women diagnosed with LCIS have already gone through menopause. LCIS is extremely uncommon in men.

LCIS is viewed as an uncommon condition, but we don’t know exactly how many people are affected. That’s because LCIS does not cause symptoms and usually does not show up on a mammogram. It tends to be diagnosed as a result of a biopsy performed on the breast for some other reason.

Male Breast Cancer

Breast cancer in men is a rare disease. Less than 1% of all breast cancers occur in men. In 2020, about 2,620 men are expected to be diagnosed with the disease, and an estimated 520 men are expected to die from breast cancer. For men, the lifetime risk of being diagnosed with breast cancer is about 1 in 833.

You may be thinking: Men don’t have breasts, so how can they get breast cancer? The truth is that boys and girls, men and women all have breast tissue. The various hormones in girls’ and women’s bodies stimulate the breast tissue to grow into full breasts. Boys’ and men’s bodies normally don’t make much of the breast-stimulating hormones. As a result, their breast tissue usually stays flat and small. Still, you may have seen boys and men with medium-sized or big breasts. Usually these breasts are just mounds of fat. But sometimes men can develop real breast gland tissue because they take certain medicines or have abnormal hormone levels.

Because breast cancer in men is rare, few cases are available to study. Most studies of men with breast cancer are very small. But when a number of these small studies are grouped together, we can learn more from them.

It’s important to understand the risk factors for male breast cancer — particularly because men are not routinely screened for the disease and don’t think about the possibility that they’ll get it. As a result, breast cancer tends to be more advanced in men than in women when it is first detected.

A number of factors can increase a man’s risk of getting breast cancer:

Growing older: This is the biggest factor. Just as is the case for women, risk increases as age increases. The average age of men diagnosed with breast cancer is about 68.

High estrogen levels: Breast cell growth — both normal and abnormal — is stimulated by the presence of estrogen. Men can have high estrogen levels as a result of:

taking hormonal medicines

being overweight, which increases the production of estrogen

having been exposed to estrogens in the environment (such as estrogen and other hormones fed to fatten up beef cattle, or the breakdown products of the pesticide DDT, which can mimic the effects of estrogen in the body)

being heavy users of alcohol, which can limit the liver’s ability to regulate blood estrogen levels

having liver disease, which usually leads to lower levels of androgens (male hormones) and higher levels of estrogen (female hormones). This increases the risk of developing gynecomastia (breast tissue growth that is non-cancerous) as well as breast cancer.

Klinefelter syndrome: Men with Klinefelter syndrome have lower levels of androgens (male hormones) and higher levels of estrogen (female hormones). Therefore, they have a higher risk of developing gynecomastia (breast tissue growth that is non-cancerous) and breast cancer. Klinefelter syndrome is a condition present at birth that affects about 1 in 1,000 men. Normally men have a single X and single Y chromosome. Men with Klinefelter syndrome have more than one X chromosome (sometimes as many as four). Symptoms of Klinefelter syndrome include having longer legs, a higher voice, and a thinner beard than average men; having smaller than normal testicles; and being infertile (unable to produce sperm).

A strong family history of breast cancer or genetic mutations: Family history can increase the risk of breast cancer in men — particularly if other men in the family have had breast cancer. The risk is also higher if there is a proven breast cancer gene abnormality in the family. Men who inherit abnormal BRCA1 or BRCA2 genes (BR stands for BReast, and CA stands for CAncer) have an increased risk of male breast cancer. The lifetime risk of developing breast cancer is approximately 1% with the BRCA1 gene mutation and 6% with the BRCA2 gene mutation. Because of this strong association between male breast cancer and an abnormal BRCA2 gene, first-degree relatives (siblings, parents, and children) of a man diagnosed with breast cancer may want to ask their doctors about genetic testing for abnormal breast cancer genes. Still, the majority of male breast cancers happen in men who have no family history of breast cancer and no inherited gene abnormality.

Radiation exposure: If a man has been treated with radiation to the chest, such as for lymphoma, he has an increased risk of developing breast cancer.

Molecular Subtypes of Breast Cancer

Breast cancer is a heterogeneous disease with different biologic subtypes that are recognized by gene expression profiling studies. Clinically, these subtypes are characterized on the basis of expression of oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Level of ER is expressed as a product of the percentage of epithelial cells stained and intensity of staining through immunohistochemistry (IHC). Historically, the cut-off value of ER-positive disease was defined as nuclear staining of ≥10% of the epithelial component of the tumour; however, in 2010 ASCO lowered the IHC cut-off for determining ER-positive status from the previous value of 10% to 1% of stained cells. This was based on the finding that even tumours weakly staining in 1% to 10% of cells demonstrated objective clinical benefit from treatment with tamoxifen. With regard to HER2 testing, ASCO released an algorithm that defined positive, equivocal, and negative values for both HER2 protein expression and gene amplification. A positive HER2 result is IHC staining of 3+ (uniform, intense membrane staining of > 30% of invasive tumor cells), a fluorescent in situ hybridization (FISH) result of more than six HER2 gene copies per nucleus, or a FISH ratio (HER2 gene signals to chromosome 17 signals) of more than 2.2. A negative result is an IHC staining of 0 or 1+, a FISH result of fewer than 4.0 HER2 gene copies per nucleus, or a FISH ratio of less than 1.8. Equivocal results (IHC staining of 2+) require additional testing for final classification.

There are five main intrinsic or molecular subtypes of breast cancer that are based on the genes a cancer expresses:

Luminal A breast cancer is hormone-receptor positive (estrogen-receptor and/or progesterone-receptor positive), HER2 negative, and has low levels of the protein Ki-67, which helps control how fast cancer cells grow. Luminal A cancers are low-grade, tend to grow slowly and have the best prognosis.

Luminal B breast cancer is hormone-receptor positive (estrogen-receptor and/or progesterone-receptor positive), and either HER2 positive or HER2 negative with high levels of Ki-67. Luminal B cancers generally grow slightly faster than luminal A cancers and their prognosis is slightly worse.

Triple-negative/basal-like breast cancer is hormone-receptor negative (estrogen-receptor and progesterone-receptor negative) and HER2 negative. This type of cancer is more common in women with BRCA1 gene mutations. Researchers aren’t sure why, but this type of cancer also is more common among younger and Black women.

HER2-enriched breast cancer is hormone-receptor negative (estrogen-receptor and progesterone-receptor negative) and HER2 positive. HER2-enriched cancers tend to grow faster than luminal cancers and can have a worse prognosis, but they are often successfully treated with targeted therapies aimed at the HER2 protein, such as Enhertu (chemical name: fam-trastuzumab-deruxtecan-nxki), Herceptin (chemical name: trastuzumab), Perjeta (chemical name: pertuzumab), Tykerb (chemical name: lapatinib), Nerlynx (chemical name: neratinib), and Kadcyla (chemical name: T-DM1 or ado-trastuzumab emtansine).

Normal-like breast cancer is similar to luminal A disease: hormone-receptor positive (estrogen-receptor and/or progesterone-receptor positive), HER2 negative, and has low levels of the protein Ki-67, which helps control how fast cancer cells grow. Still, while normal-like breast cancer has a good prognosis, its prognosis is slightly worse than luminal A cancer’s prognosis.

Paget’s Disease of the Nipple

Paget’s disease of the nipple is a rare form of breast cancer in which cancer cells collect in or around the nipple. The cancer usually affects the ducts of the nipple first (small milk-carrying tubes), then spreads to the nipple surface and the areola (the dark circle of skin around the nipple). The nipple and areola often become scaly, red, itchy, and irritated.

Paget’s disease of the nipple accounts for less than 5% of all breast cancer cases. Being aware of the symptoms is important, given that more than 97% of people with Paget’s disease also have cancer, either DCIS or invasive cancer, somewhere else in the breast. The unusual changes in the nipple and areola are often the first indication that breast cancer is present.

Doctors are not yet completely sure how Paget’s disease develops. One possibility is that the cancer cells start growing inside the milk ducts within the breast and then make their way out to the nipple surface. This would appear to explain why so many people with Paget’s disease of the nipple have a second area of cancer within the breast. Another theory is that the cells of the nipple itself become cancerous. This theory would explain the small number of people who: (1) only have Paget’s disease in the nipple, or (2) have a second breast cancer that appears to be completely separate from the Paget’s disease.

Paget’s disease of the nipple is more common in women, but like other forms of breast cancer, it can also affect men. The disease usually develops after age 50. The average age of diagnosis in women is 62, and in men, 69.

Phyllodes Tumors of the Breast

Phyllodes tumors of the breast are rare, accounting for less than 1% of all breast tumors. The name “phyllodes,” which is taken from the Greek language and means “leaflike,” refers to that fact that the tumor cells grow in a leaflike pattern. Other names for these tumors are phylloides tumor and cystosarcoma phyllodes. Phyllodes tumors tend to grow quickly, but they rarely spread outside the breast.

Although most phyllodes tumors are benign (not cancerous), some are malignant (cancerous) and some are borderline (in between noncancerous and cancerous). All three kinds of phyllodes tumors tend to grow quickly, and they require surgery to reduce the risk of a phyllodes tumor coming back in the breast (local recurrence).

Phyllodes tumors can occur at any age, but they tend to develop when a woman is in her 40s. Benign phyllodes tumors are usually diagnosed at a younger age than malignant phyllodes tumors. Phyllodes tumors are extremely rare in men.

Metastatic Breast Cancer

Metastatic breast cancer (also called stage IV) is breast cancer that has spread to another part of the body, most commonly the liver, brain, bones, or lungs.

Cancer cells can break away from the original tumor in the breast and travel to other parts of the body through the bloodstream or the lymphatic system, which is a large network of nodes and vessels that works to remove bacteria, viruses, and cellular waste products.

Breast cancer can come back in another part of the body months or years after the original diagnosis and treatment. Nearly 30% of women diagnosed with early-stage breast cancer will develop metastatic disease.

Some people have metastatic breast cancer when they are first diagnosed with breast cancer (called “de novo metastatic”). This means that the cancer in the breast wasn’t detected before it spread to another part of the body.

A metastatic tumor in a different part of the body is made up of cells from the breast cancer. So if breast cancer spreads to the bone, the metastatic tumor in the bone is made up of breast cancer cells, not bone cells.

Being diagnosed with metastatic breast cancer can be overwhelming. You may feel angry, scared, stressed, outraged, and depressed. Some people may question the treatments they had or may be mad at their doctors or themselves for not being able to beat the disease. Others may deal with diagnosis of metastatic breast cancer in a matter-of-fact way. There is no right or wrong way to come to terms with the diagnosis. You need to do and feel what is best for you and your situation.

Keep in mind that metastatic disease is NOT hopeless. Many people continue to live long, productive lives with breast cancer in this stage. There are a wide variety of treatment options for metastatic breast cancer, and new medicines are being tested every day. More and more people are living life to the fullest while being treated for metastatic breast cancer.

While metastatic breast cancer may not go away completely, treatment may control it for a number of years. If one treatment stops working, there usually is another you can try. The cancer can be active sometimes and then go into remission at other times. Many different treatments — alone, in combination, or in sequence — are often used. Taking breaks in treatment when the disease is under control and you are feeling good can make a big difference in your quality of life.

Metastatic Breast Cancer Symptoms and Diagnosis

The symptoms of metastatic breast cancer can vary greatly depending on the location of the cancer. This section covers the symptoms of breast cancer that has spread to the bone, lung, brain, and liver, and the tests used to diagnose metastatic breast cancer.

Bone Metastasis: Symptoms and Diagnosis

The most common symptom of breast cancer that has spread to the bone is a sudden, noticeable new pain. Breast cancer can spread to any bone, but most often spreads to the ribs, spine, pelvis, or the long bones in the arms and legs.

Lung Metastasis: Symptoms and Diagnosis

When breast cancer moves into the lung, it often doesn’t cause symptoms. If a lung metastasis does cause symptoms, they may include pain or discomfort in the lung, shortness of breath, persistent cough, and others.

Brain Metastasis: Symptoms and Diagnosis

Symptoms of breast cancer that has spread to the brain can include headache, changes in speech or vision, memory problems, and others.

Liver Metastasis: Symptoms and Diagnosis

When breast cancer spreads to the liver, it often doesn’t cause symptoms. If a liver metastasis does cause symptoms, they can include pain or discomfort in the mid-section, fatigue and weakness, weight loss or poor appetite, fever, and others.

Metastatic Breast Cancer Treatment and Planning

After a diagnosis of metastatic breast cancer, it’s helpful to take all the time you need to gather information and make decisions about your treatment. Learn about the medical specialists that may be involved in your care, treatment options, genetic testing, taking a break from treatment, and more.

Surgery

Doctors sometimes recommend surgery for metastatic breast cancer in order, for example, to prevent broken bones or cancer cell blockages in the liver.

Chemotherapy

Chemotherapy is used in the treatment of metastatic breast cancer to damage or destroy the cancer cells as much as possible.

Radiation Therapy

Your doctor may suggest radiation therapy if you’re having symptoms for reasons such as easing pain and controlling the cancer in a specific area. Learn more.

Hormonal Therapy

Hormonal therapy medicines are used to help shrink or slow the growth of hormone-receptor-positive metastatic breast cancer.

Targeted Therapy

Targeted therapies target specific characteristics of cancer cells, such as a protein that allows the cancer cells to grow in a rapid or abnormal way.

Local Treatments for Distant Areas of Metastasis

Local treatments are directed specifically to the new locations of the breast cancer such as the bones or liver. These treatments may be recommended if, for example, the metastatic breast cancer is causing pain.

Genetic Testing and Metastatic Breast Cancer

A licensed certified genetic counselor discusses the benefits of genetic counseling and genetic testing for people with metastatic breast cancer and a woman living with metastatic breast cancer shares why she chose to undergo genetic counseling.

Complementary and Holistic Medicine and Metastatic Breast Cancer

Practices such as acupuncture, massage, hypnosis, meditation, and yoga can help ease the symptoms of metastatic breast cancer, lessen treatment side effects, and improve quality of life.

Clinical Trials for Metastatic Breast Cancer

Clinical trials for metastatic breast cancer are an important step in discovering new treatments and improving the standard of care. They can also help eligible patients receive new treatments.

Taking a Break From Treatment for Metastatic Breast Cancer

Many people with metastatic breast cancer decide at some point to take a break from treatment or to stop treatment. You need to discuss many issues to consider when weighing those decisions

Living With Metastatic Breast Cancer

A metastastic breast cancer diagnosis can be a lot to manage, physically and emotionally. Read about ways to live with metastatic breast cancer, including working after your diagnosis, facing fears, getting emotional support, and more.

Planning Ahead: End-of-Life Issues

If you’re thinking about stopping treatment for metastatic breast cancer, learn about issues to consider such as managing symptoms, organizing your finances, choosing a hospice program, and more.

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