Types of Breast Cancer2020-02-01T15:42:16+00:00

Types of Breast Cancer

There are many types of breast cancer and it’s easy to get confused over a breast cancer diagnosis.

The type of breast cancer is determined by the specific cells in the breast that are affected. Most breast cancers are carcinomas, which are tumours that start in the epithelial cells that line organs and tissues throughout the body. When carcinomas form in the breast, they are usually a more specific type called adenocarcinoma, which starts in cells in the ducts (the milk ducts) or the lobules (milk-producing glands).


Ductal Carcinoma In Situ (DCIS)

Ductal carcinoma in situ (DCIS) is a non-invasive cancer where abnormal cells have been found in the lining of the breast milk duct. The atypical cells have not spread outside of the ducts into the surrounding breast tissue. Ductal carcinoma in situ is very early cancer that is highly treatable, but if it’s left untreated or undetected, it can spread into the surrounding breast tissue.

People diagnosed with DCIS usually don’t have symptoms and this early stage of breast cancer is usually picked up by mammograms.


Treatment of DCIS has a high likelihood of success, in most instances removing the tumour and preventing any recurrence.

In most people, treatment options for DCIS include:

  • Breast-conserving surgery (lumpectomy) and radiation therapy
  • Breast-removing surgery (mastectomy)

In some cases, treatment options may include:

  • Lumpectomy only
  • Lumpectomy and hormone therapy
  • Participation in a clinical trial comparing close monitoring with surgery

Invasive Ductal Carcinoma (IDC)

The abnormal cancer cells that began forming in the milk ducts have spread beyond the ducts into other parts of the breast tissue. Invasive cancer cells can also spread to other parts of the body. It is also sometimes called infiltrative ductal carcinoma.

  • IDC is the most common type of breast cancer, making up nearly 70- 80% of all breast cancer diagnoses.
  • IDC is also the type of breast cancer that can most commonly affects men. Cases of breast cancer in men are only 1% of total breast cancer cases.


Treatments for invasive ductal carcinoma (IDC) include surgery, chemotherapy, radiation therapy, hormonal therapy, and targeted therapy. You and your doctor will decide what treatment or combination of treatments is right for you depending on the characteristics of the cancer and your personal preference.

Triple Negative Breast Cancer

A diagnosis of triple negative breast cancer means that the three most common types of receptors known to fuel most breast cancer growth–estrogen, progesterone, and the HER-2/neu gene– are not present in the cancer tumour.  This means that the breast cancer cells have tested negative for hormone epidermal growth factor receptor 2 (HER-2), estrogen receptors (ER), and progesterone receptors (PR). 

Since the tumour cells lack the necessary receptors, targeted treatments like hormone therapy and that target estrogen, progesterone and targeted therapy for HER-2 positive cases are ineffective. Using chemotherapy to treat triple negative breast cancer is an effective option.


Triple-negative breast cancer is typically treated with a combination of surgery, radiation therapy, and chemotherapy. Immunotherapy, which boosts the immune system of the body, is now being recognised as a potential therapeutic approach in treating TNBC. It uses the body’s own molecules or synthetically produced substances that enhance or restore the immune system. Moreover, scientists are working hard to find more and better ways to treat TNBC.

Inflammatory Breast Cancer (IBC)

Inflammatory breast cancer is an aggressive breast cancer in which cancer cells infiltrate the skin and lymph vessels of the breast. It resembles infection and hence often missed even by doctors.It often produces no distinct tumour or lump that can be felt and isolated within the breast.  But when the lymph vessels become blocked by the breast cancer cells, symptoms begin to appear.


Inflammatory breast cancer (IBC) that has not spread outside the breast or nearby lymph nodes is stage 3. In most cases, treatment is chemotherapy first to try to shrink the tumour, followed by surgery to remove the cancer. Radiation is given after surgery, and in some cases, more treatment may be given after radiation. Because IBC is so aggressive, breast conserving surgery (lumpectomy) and sentinel lymph node biopsy are typically not part of the treatment.

IBC that has spread to other parts of the body (stage IV) may be treated with chemotherapy, hormone therapy, and/or with drugs that targets HER2.

Medullary Carcinoma

It is a form of Invasive Ductal Carcinoma. Medullary carcinoma accounts for 3-5% of all breast cancer types.  The tumour usually shows up on a mammogram but does not always feel like a lump.  At times, it feels like a spongy change of breast tissue. Medullary carcinoma is more common in women who have a BRCA1 mutation.


A typical medullary carcinoma would receive the same treatments as invasive ductal carcinoma.

You can work with your doctor to come up with the treatment plan that is right for you, based on the features of the cancer such as tumour size, grade, and whether or not the cancer has spread to any lymph nodes. Most medullary carcinomas test negative for estrogen and progesterone receptors. Therefore, they usually cannot be treated with hormonal therapies such as tamoxifen or aromatase inhibitors, which interfere with estrogen’s ability to promote cancer cell growth. Medullary carcinomas also usually test negative for HER2 receptors, so cannot be treated with anti-HER2 medicines

Tubular Carcinoma

Making up about 2% of all breast cancer diagnosis, tubular carcinoma cells have a distinctive tube like structure when viewed under a microscope. It is usually found through a mammogram and is a collection of cells that can feel like a spongy area of breast tissue rather than a lump. Normally, this type of breast cancer is found in women aged 50+.


Even though tubular carcinoma is an invasive breast cancer, it tends to be a less aggressive type that responds well to treatment. It isn’t likely to spread outside the breast and is considered to have a very good prognosis. Numerous treatment options are available for people who have tubular carcinoma. A person can discuss these options with their doctor. The best treatment option will depend on the diagnostic test results and the individual’s preferences.

Treatment options for tubular carcinoma include the following:

  • Lumpectomy
  • Mastectomy
  • Radiation therapy
  • Hormone therapy
  • Chemotherapy
  • Targeted therapy (involves medications that target the proteins in cancer cells)

Mucinous Carcinoma (Colloid)

Mucinous carcinoma represents approximately 1% to 2% of all breast cancers. The main differentiating features are mucus production and cells that are poorly defined. It also has a favourable prognosis in most cases.


Even though mucinous carcinoma is an invasive breast cancer, it tends to be a less aggressive type that responds well to treatment. Mucinous carcinoma is less likely to spread to the lymph nodes than other types of breast cancer. Treatment options vary based on the area of the body the cancer is, the stage of the cancer at diagnosis, as well as other health factors. However, in most cases you will have either one or a combination of the following treatment options:

  • Surgery
  • Radiation therapy
  • Chemotherapy
  • Hormonal therapy to block or lower the amount of estrogen
  • Other targeted therapies

Paget Disease of the Breast or Nipple

This condition is a rare type of cancer affecting the skin of the nipple and often the areola, which is the darker circle of skin around the nipple. Like all breast cancers, the prognosis for Paget disease depends on a variety of factors, including the presence or absence of invasive cancer and whether it has spread to nearby lymph nodes.


If you have Paget’s disease of the breast, you will likely need surgery. The type of surgery depends on the condition of the skin around your nipple and how advanced the underlying cancer is.

Treatment options include:

  • Simple mastectomy
  • Lumpectomy (Lumpectomy to treat Paget’s disease of the breast requires follow-up radiation therapy. Lumpectomy wouldn’t be recommended if you can’t have radiation therapy for some reason. Most women have nipple reconstruction after their treatment.)
  • Chemotherapy
  • Hormone therapy

Your specific treatment will depend on the extent of the cancer and whether your tumour tests positive for certain characteristics, such as having hormone receptors or HER-2 positivity.

Metastatic Breast Cancer

Metastatic breast cancer is also classified as Stage 4 breast cancer, where it has spread to other parts of the body.  This may usually include lungs, liver, bones or brain.

The spread of cancer usually happens through one or more of the following steps:

  • Cancer cells invade nearby healthy cells. When the healthy cell is taken over, it too can replicate more abnormal cells.
  • Cancer cells penetrate the circulatory or lymph system. Cancer cells travel through the walls of nearby lymph vessels or blood vessels.
  • Migration through circulation. Cancer cells are carried by the lymph system and the bloodstream to other parts of the body.
  • Cancer cells lodge in capillaries. Cancer cells stop moving as they are lodged in capillaries at a distant location and divide and migrate into the surrounding tissue.
  • New small tumors grow. Cancer cells form small tumors at the new location (called micro-metastases)


Unfortunately, metastatic breast cancer cannot be cured today. Unlike breast cancer that remains in the breast or nearby lymph nodes, you can’t get rid of all the cancer that has spread to other organs.

This doesn’t mean metastatic breast cancer can’t be treated though. Treatment focuses on length and quality of life. If the cancer is hormone receptor-positive, the first treatment is often hormone therapy. If the cancer is HER2-positive, anti HER2 therapies such as trastuzumab (Herceptin) may be given. For triple negative breast cancers that are sensitive to immunotherapy, the first treatment may be the immunotherapy drug in combination with chemotherapy. Chemotherapy and radiation therapy can be used to shrink or slow the growth of tumours or to ease symptoms of the cancer itself. However, these therapies have side effects that can affect quality of life.

Benign breast cancer conditions

Most people associate breast abnormalities with breast cancer. However, not all breast disorders are cancerous. There are many benign (non-cancerous) breast conditions.

A benign breast condition refers to a lump, cyst, or nipple discharge (fluid) of the female or male breast that is not cancerous. For women, the most common ones are:

  • Fibrocystic breast changes – Fibrosis feels like scar tissue and can be rubbery and firm. Cysts are sacs filled with fluid. They may enlarge and feel tender right before your period.
  • These are the most common breast lumps in younger women and are usually small.
  • Your breast can become enlarged because of infection. This can happen to anyone but usually happens when breastfeeding.
  • Fat necrosis – These lumps form when areas of fatty breast tissue are damaged.
  • Small spots of calcium salts can show up anywhere in breast tissue. Usually, you can’t feel them and they’re not painful.
  • Nipple discharge. Your nipples may leak fluid for a variety of reasons.
  • These are made up of mostly fat tissue.

Less common types of benign breast conditions include:

  • Abnormal increase in cell growth in the breast
  • Enlarged lobules in breasts that contain more glands than usual
  • Intraductal papillomas – Small tumours that form in nipple’s milk ducts

Remember, if we are determined & disciplined, cancer can be defeated. Live life to the fullest and say Yes to Life!