Breast Cancer Information – Macmillan Cancer Support

Breast cancer

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What is breast cancer?

Overview

Breast cancer is when cells in the breast multiply in an abnormal way and grow out of control. This is the most common cancer type in women, but it can affect anyone. We have information about breast cancer in men and transgender people.

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Statistics

About 55,000 women are diagnosed with breast cancer each year in the UK. It is most common in women over 50, but can also affect younger women.

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Invasive breast cancer

Breast cancer can be invasive or non-invasive. Invasive breast cancer means cancer cells have spread beyond the milk ducts or lobules in the breasts into surrounding tissue.

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DCIS

Ductal carcinoma in situ (DCIS) is the earliest form of breast cancer. It is not life-threatening. But treatment is usually recommended to stop it developing into breast cancer.

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Information and support for men

Each year, about 375 men are diagnosed with breast cancer in the UK. Find information and support on our breast cancer in men page.

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Understanding breast cancer

Breast cancer explained

Breast Cancer Explained: Symptoms, Stages and Treatment

Dr. Aziza Sesay, General Practitioner

Watch on YouTube (opens in a new tab)

Signs and symptoms

A lump in the breast is the most common symptom of breast cancer. Most breast lumps are not cancer but

A lump in the breast is the most common symptom of breast cancer. Most breast lumps are not cancer but it is always important to get checked by your doctor.

See your GP if you have any symptoms or notice anything else that is unusual for you. If breast cancer is diagnosed and treated early, treatment is more likely to be successful.

Related pages

Causes and risks

Breast cancer is likely to be caused by a combination of things. The biggest risk factor is age.

Breast cancer is likely to be caused by a combination of things. The biggest risk factor is age. About 8 in 10 women diagnosed (80%) are over the age of 50.

Find out more about breast cancer risk factors.

The importance of checking your breasts

Bami's breast cancer story

Watch on YouTube (opens in a new tab)

Diagnosis

Getting a diagnosis

You usually start by seeing your GP. They will examine you and refer you to a breast clinic to see a specialist.

You usually start by seeing your GP. They will examine you and refer you to a breast clinic to see a specialist. Or you may be referred through NHS breast screening programmes. This is usually if there are changes on your mammogram. Breast screening is a way of finding breast cancer at an early stage, when it is too small to be felt or seen.

At the breast clinic

At the clinic, you will see a specialist breast doctor or a nurse. You may also see a breast care nurse. They usually ask you if:

  • you have had any other breast problems or health problems
  • anyone in your family has had breast cancer or ovarian cancer
  • you have been through the menopause
  • you are taking any medicines – for example, hormone replacement therapy (HRT) or the contraceptive pill.

The doctor or nurse will examine your breast or chest area and the lymph nodes in your armpits and above your collarbone.

Tests

Mammogram

A mammogram is a low-dose x-ray of the breast.

Breast ultrasound

A breast ultrasound uses sound-waves to build up a picture of the breast tissue. You will also have an ultrasound scan of the lymph nodes in the armpit.

Breast biopsy

During a breast biopsy, the doctor removes a small piece of tissue or cells from the lump or abnormal area. The sample is checked for cancer cells. There are different ways of taking a breast biopsy.

Further tests after diagnosis

You may have further tests to find out more about the cancer.

MRI

An MRI scan uses magnetism to build up detailed pictures of your body. It may be done to find out the size of the cancer and help decide on the operation you have.

CT scan

A CT scan takes a series of x-rays, which build up a three-dimensional picture of the inside of the body.

Bone scan

A bone scan shows up abnormal areas of bone. You have a small amount of a radioactive substance injected into a vein and wait for 2 to 3 hours to have the scan.

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Planning your treatment

Your treatment plan

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT). Your doctors look at different factors to help decide which treatments are likely to work best for you.

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT). Your doctors look at different factors to help decide which treatments are likely to work best for you.

Your doctor or breast care nurse will talk to you about your treatment plan before you make any decisions about treatment. They will explain the benefits and any side effects of the treatments. You can ask them any questions you have.

Breast cancer types

There are different types of breast cancer, and knowing your type helps doctors choose the most appropriate treatment.

Staging and grading

The results of your tests help your doctors find out more about the size and position of the cancer and whether it has spread. This is called staging. A doctor decides the grade of the cancer by how the cancer cells look under the microscope. This gives an idea of how quickly the cancer might grow or spread.

The results of your tests help your doctors find out more about the size and position of the cancer and whether it has spread. This is called staging. A doctor decides the grade of the cancer by how the cancer cells look under the microscope. This gives an idea of how quickly the cancer might grow or spread.

Knowing the stage and grade helps your doctors plan the best treatment for you. This information is about stage 1 to 3 breast cancer. If you have stage 4 breast cancer, you may find our information about secondary breast cancer helpful.

Receptors for breast cancer

Your treatment plan also depends on whether the breast cancer cells have certain receptors or proteins on their surface. A sample of cancer cells from biopsy or surgery is tested for these.

Your treatment plan also depends on whether the breast cancer cells have certain receptors or proteins on their surface. A sample of cancer cells from biopsy or surgery is tested for these.

Hormone receptors

Breast cancer that has receptors for the hormone oestrogen is called oestrogen receptor positive or ER positive breast cancer. The term ER is used because the American spelling of oestrogen is estrogen.

About 7 in 10 breast cancers in women (70%) are ER positive. Breast cancer can also have receptors for the hormone progesterone (PR positive breast cancer). Your doctor will explain whether testing for progesterone receptors is useful in your situation.

HER2 receptors

Some breast cancers have too much of a protein called HER2. These are called HER2 positive breast cancers. Targeted therapies can be used to treat HER2 positive breast cancers.

Triple negative breast cancer

Some breast cancers do not have any of these receptors. This is called triple negative breast cancer.

Treatment

Treatment options

The first treatment for breast cancer is often surgery to remove it. You may also have other treatments before or after surgery.

The first treatment for breast cancer is often surgery to remove it. You may also have other treatments before or after surgery.

Breast Conserving Surgery

Breast conserving surgery removes the cancer and a small area (margin) of healthy tissue around it. It is also called a wide local excision or lumpectomy. The aim is to keep as much of the breast as possible while making sure the cancer is completely removed.

Mastectomy

Mastectomy is surgery to remove all the breast tissue on the affected side.

Surgery to remove lymph nodes

You will usually also need some, or all, of the lymph nodes in your armpit removed.

Breast reconstruction

Breast reconstruction is surgery to make a new breast shape. You may have this after mastectomy or if a large area of tissue needs to be removed during breast conserving surgery.

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Other treatments

After surgery, you may have one or more of the following treatments to reduce the risk of the cancer coming back. Some people may also have these treatments before surgery. For example, to shrink a larger cancer.

After surgery, you may have one or more of the following treatments to reduce the risk of the cancer coming back. Some people may also have these treatments before surgery. For example, to shrink a larger cancer.

Radiotherapy

Radiotherapy uses high-energy rays to destroy cancer cells in the breast or chest area.

Chemotherapy

Chemotherapy uses anti-cancer drugs to destroy cancer cells.

Hormonal Therapy

Hormonal therapy drugs are used to treat breast cancers that are oestrogen-receptor positive (ER+).

Targeted Therapy

Targeted therapies interfere with the way cancer cells grow. These drugs are often used to treat HER2 positive breast cancer.

Bisphosphonates

Bisphosphonates are drugs that help to protect the bones against some effects of breast cancer treatments. They can also help reduce the risk of the cancer spreading to the bones.

‐Talking about cancer, it's really important. The old Vicky is no more. My life has taken a different part. I need to recognise that this is my new normal. I need to fit into a new life."

Vicky
Read Vicky's journey through breast cancer treatment

After treatment

After breast cancer treatment

After treatment, you will have regular check-ups with your cancer doctor or regular contact with your breast care nurse. Follow-up appointments are a good time to talk to your cancer doctor or specialist nurse about any concerns you have.

After treatment, you will have regular check-ups with your cancer doctor or regular contact with your breast care nurse. Follow-up appointments are a good time to talk to your cancer doctor or specialist nurse about any concerns you have.

You will have yearly mammograms, unless you have had surgery to remove both breasts (double mastectomy). This is to look for any changes in the remaining breast tissue. Mammograms usually continue for 5 years, or until you are invited to have NHS breast screening (opens in a new tab).

Be aware of changes

It is important to be aware of how your breast or chest area looks and feels after treatment. If you notice any new symptoms or changes, tell your breast care nurse or doctor straight away.

Lymphoedema

Treatment for breast cancer can sometimes cause swelling in the arm or hand on the side you had surgery. This is called lymphoedema.

Sex and fertility

Breast cancer and its treatments can affect your sex life and your fertility. Your doctor or nurse can give you support and information.

Early menopause

Some treatments can cause an early or temporary menopause. This can cause menopausal symptoms such as hot flushes and sweats. Early menopause can increase the risk of longer-term problems, including with bone health.

Well-being and recovery

After treatment, it can take time to adjust and recover. Looking after your well-being can help.

Related links

"The stories Macmillan shares help those diagnosed with cancer to understand they are not alone, and the information about treatments and cancer is easy to understand, accurate, supportive and helpful."

Katie
Read Katie's and more stories about support during breast cancer

Other languages and formats

Other ways to access our content

We are committed to making our website as accessible as possible, to make sure that everyone can use it.

We have information about breast cancer in over 16 languages.

We also have other formats available, including audiobooks, and easy read.

If we don't have what you are looking for, you can ask for information to be translated for free or provided in a format to suit you. Email us at cancerinformationteam@macmillan.org.uk or call us on 0808 808 00 00.

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Cancer information

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Understanding breast cancer
Audiobook
Understanding breast cancer >
Ask about your cancer treatment
Booklet
Ask about your cancer treatment >
Managing the late effects
Booklet
Managing the late effects of breast cancer >
Real stories
Stories
Real stories of support during breast cancer >

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Reviewed:Oct '2023
Next Review:Oct '2026

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