Invasive breast cancer

Invasive breast cancer (no special type or NST) is the most common type of breast cancer.

What is invasive breast cancer?

Invasive breast cancer means that the cancer cells have grown through the lining of the ducts into the surrounding breast tissue. Between 70 and 80 out of 100 (between 70 and 80%) breast cancers are this type.

Most invasive breast cancers have no special features and are classed as No Special Type (NST) or not otherwise specified (NOS). 

Special type means that when the doctor looks at the cancer cells under a microscope the cells have particular features. Breast cancers that are classed as special types include some rare types of breast cancer.

Ductal carcinoma in situ

Invasive breast cancer is different from ductal carcinoma in situ (DCIS). In invasive cancer, the cells have broken out of the duct and spread into the surrounding breast tissue. DCIS means that some cells have started to turn into cancer but these cells are all contained inside the ducts. 

Diagram showing ductal carcinoma in situ (DCIS)

Remember that if your doctor has told you that you have ductal carcinoma in situ (DCIS), you don't have invasive breast cancer.

Symptoms of invasive breast cancer

Make an appointment to see your doctor if you notice anything different or unusual about the look and feel of your breasts.

The symptoms of breast cancer include:

  • a new lump or thickening in your breast or armpit
  • a change in size, shape or feel of your breast
  • skin changes in the breast such as puckering, dimpling, a rash or redness of the skin
  • fluid leaking from the nipple in a woman who isn’t pregnant or breast feeding
  • changes in the position of nipple

Diagnosing invasive breast cancer

Your GP may refer you to a breast clinic if you have any symptoms that could be due to invasive breast cancer. You may also be referred to a breast clinic for tests if your screening mammogram shows an abnormal area. 

You usually have a number of tests to check for breast cancer. This includes:

  • a mammogram Open a glossary item 
  • a breast ultrasound scan Open a glossary item
  • taking a sample of tissue from your breast called a biopsy 


To decide on the most appropriate treatment, doctors generally take into account: 

  • the type of breast cancer
  • the size of the cancer and whether it has spread (the stage)
  • how abnormal the cells look under the microscope (the grade)
  • whether the cancer cells have receptors for particular hormones
  • whether the cells have receptors for targeted cancer drug therapy
  • your general health

For invasive breast cancer you might have:

  • surgery to the breast
  • radiotherapy
  • chemotherapy
  • hormone therapy
  • targeted drug therapy
  • drugs that help prevent or slow down bone thinning (osteoporosis) or bone damage
  • a combination of these treatments

You may have surgery to your armpit called a sentinel lymph node biopsy. This means having about 3-5 lymph nodes removed. Sometimes surgeons have to remove more lymph nodes. Your doctor will let you know whether you need this. 

You might have chemotherapy or hormone therapy before surgery called neoadjuvant therapy. The aim is to shrink the cancer down. This means that some people may be able to have breast conserving surgery, who might have needed removal of the breast (mastectomy). 

Breast-conserving surgery removes the cancer while leaving as much normal breast tissue as possible. Some people may have a mastectomy, this is surgery to remove the whole breast.

If you have a mastectomy you might be able to have a new breast made (breast reconstruction). This may be at the same time as the mastectomy or some time afterwards.

Your doctor considers many things before deciding the best treatment for you. This is why your treatment may be different from other people with breast cancer.

Follow up

After treatment you usually have regular check ups. At the check ups your doctor or a breast care nurse will examine you and ask about your general health. This is your chance to ask questions and to tell them if anything is worrying you.

How often you have check ups depends on your individual situation but you might have them for at least 5 years. This might include yearly mammograms. 

It’s important to remember that you can contact your doctor or nurse between appointments if you are worried about a symptom or have questions. You don't have to wait for your next appointment. You can also speak to your GP.

In some hospitals you don't have regular appointments after treatment. But if you have new symptoms or are worried about anything you can phone your doctor or breast care nurse or make an appointment to see them. 

UK guidelines say that everyone who has had treatment for early breast cancer should have a copy of a written care plan. The care plan has information about tests you will have, and signs and symptoms to look out for. It will also include contact details for specialist staff, such as your breast care nurse.

Trials and research

Invasive breast cancer is the most common type of breast cancer. So most breast cancer research is looking at this type.

Research includes:

  • the causes and prevention of breast cancer
  • screening and diagnosis
  • new treatments
  • ways to improve existing treatments
  • ways to cope with cancer and its treatment
  • Early and locally advanced breast cancer: diagnosis and treatment
    National Institute for Health and Care Excellence (NICE), June  2018

  • A Brief Overview of the WHO Classification of Breast Tumors, 4th Edition, Focusing on Issues and Updates from the 3rd Edition
    H Sinn and H Kreipeb
    Breast Care, 2013. Volume 8

  • Early Breast Cancer: ESMO Clinical Practice Guidelines
    F Cardoso and others 
    Annals of oncology, 2019. Volume 30, Pages 1194-1220.

  • Invasive lobular breast cancer and its variants: How special are they for systemic therapy decisions?
    S Guiu and others
    Critical Reviews in Oncology/Haematology, 2014. Volume 92, Issue 3, Pages 235-257

Last reviewed: 
13 Feb 2020

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