A study looking at radiotherapy for women with a very small risk of their breast cancer returning (PRIMETIME)

Please note - this trial is no longer recruiting patients. We hope to add results when they are available.

Cancer type:

Breast cancer

Status:

Closed

Phase:

Other

This study is to see if women who only have a very small risk of their breast cancer returning need to have radiotherapy after surgery. 

Cancer Research UK supports this study.

More about this trial

The main treatment for women with breast cancer is surgery followed by radiotherapy Open a glossary item with or without hormone treatment Open a glossary item.

Radiotherapy reduces the risk of the cancer coming back in the breast (local recurrence). But radiotherapy has side effects. For women who only have a very small chance of their cancer coming back, the side effects of radiotherapy could outweigh the benefits.

In this study researchers do an extra test on the sample already taken from a biopsy Open a glossary item. This is called a Ki67 test. The result of the Ki67 test is used with other routine test results and information about the type of breast cancer. From this the researchers can create a score which can show who might be at a:

  • low risk of their cancer coming back
  • very low risk of their cancer coming back

This score is called the IHC4+C score.

The study aims to find out:

  • which women are at very low risk of their breast cancer coming back
  • if these women can avoid having radiotherapy treatment

Who can enter

The following bullet points list the entry conditions for this study. Talk to your doctor or the study team if you are unsure about any of these. They will be able to advise you. 

You may be able to join this study if all of the following apply. You are a woman and you

  • Have had breast conserving surgery
  • Have a stage 1a invasive breast cancer that is grade 1 or 2 (you might be able to take part if you have both DCIS and invasive breast cancer your doctor can advise you)
  • Have hormone receptor positive breast cancer for oestrogen
  • Have had hormone receptor testing for progesterone
  • Have human epidermal growth factor (HER2 Open a glossary item) negative breast cancer
  • Are due to have at least 5 years of hormone therapy treatment after your surgery
  • Are aged at least 60 years old

Women younger than 60 who have been through the menopause and who their doctor thinks would find radiotherapy difficult because of other medical conditions may be able to take part. They would need to have had the same treatment and type and stage of breast cancer as listed above.  

You cannot join this study if any of these apply. You

  • Have had your whole breast removed as treatment for your cancer
  • Have breast cancer that has spread to your blood vessels and lymphatic system, or you have cancer in the lymph nodes under your arm
  • Had a breast cancer lump that your doctors couldn’t see on a mammogram Open a glossary item 
  • Had hormone therapy or chemotherapy Open a glossary item before your breast cancer surgery
  • Need chemotherapy after your breast cancer surgery
  • Have had cancer in the past apart from carcinoma in situ of the cervix, basal cell skin cancer or squamous cell skin cancer Open a glossary item that was successfully treated. Or you have had another cancer in the past, which was successfully treated and you have been cancer free for at least 5 years. 

Trial design

 The researchers need around 2,400 women to take part. 

Before you have your surgery the study team ask your permission to do the Ki67 test. This means they have the results of the test quite soon after your operation and so there are no delays to any treatment you might need. If you agree to the test your doctor will have your results. If you are suitable to take part in the main study they will tell you more about it.  You don’t have to take part in the main study if you don’t want to. This won’t affect the care you have. 

If you decide to take part in the study, a doctor or nurse will talk to you about your risk group result. This is your IHC4+C score. 

If you in the ‘very low risk’ group, you have at least 5 years of hormone treatment and no radiotherapy.

If you are not in the ‘very low risk’ group you have standard treatment for breast cancer. This is at least 5 years of hormone treatment and radiotherapy.

This is a patient choice study. This means you can decide if you want to have the treatment plan based on the IHC4+C score and risk group.

Samples for research

The study team will ask your permission to use a sample of tissue that was removed when you had surgery for future research. 

If you are ever treated again for cancer they would like to collect a small part of cancer tissue taken from any routine biopsies or surgery you have. 

The team will use these samples to learn more about breast cancer, radiotherapy and why some cancers come back. 

You do not have to agree to give these samples for research. You can still take part in the main study.

Information Giving Study (IGS)

Please note - this part of the study is now closed.

The study team would also like to find out your views on the information you received about the PRIMETIME study. The aim is to see if the information you received helped you to decide whether or not you would like to take part in PRIMETIME.

You fill in a questionnaire after you have made your decision about if you want to take part in PRIMETIME.

You can take part in the PRIMETIME main study and not take part in the PRIMETIME Information Giving Study.

Hospital visits

If you have radiotherapy your doctor will talk to you about how often you go to the hospital. But you usually have it Monday to Friday with a break at the weekend. The treatment is usually over 3 to 5 weeks. You also have hormone therapy for at least 5 years.

You have a mammogram every year for the first 5 years. After this you have routine breast screening, which is a mammogram every three years until you are 70. After the age of 70 you can request a mammogram. 

You see your doctor during and when you finish your treatment as you would do usually.

You might be contacted by the study team to see how you are after you have finished all your breast cancer treatment.

If you don’t have radiotherapy you should have hormone therapy for at least 5 years. You have a mammogram every year for the first 10 years. After this you have routine breast screening.

You see your doctor for routine follow up appointments as you would do usually.

You might be contacted by the study team to see how you are after you have finished all your breast cancer treatment.

Side effects

For radiotherapy for breast cancer, the side effects might include:

  • change in breast shape
  • your breast getting smaller (breast shrinkage)
  • tenderness

Rare side effects include:

  • heart damage
  • the risk of a second cancer some years after treatment

We have more information about the side effects of radiotherapy.

For hormone therapy in women side effects might include:

  • menopausal symptoms
  • muscle and bone changes
  • tiredness

We have more information on the side effects of hormone therapy in women.

Recruitment start:

Recruitment end:

How to join a clinical trial

Please note: In order to join a trial you will need to discuss it with your doctor, unless otherwise specified.

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Chief Investigator

Dr Charlotte Coles

Supported by

Cancer Research UK
Institute of Cancer Research (ICR)
ICR Clinical Trials and Statistics Unit (ICR-CTSU)
University of Cambridge

If you have questions about the trial please contact our cancer information nurses

Freephone 0808 800 4040

Last review date

CRUK internal database number:

14811

Please note - unless we state otherwise in the summary, you need to talk to your doctor about joining a trial.

Last reviewed:

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