A trial of hormone therapy 2 weeks before and after surgery for early breast cancer (POETIC)

Cancer type:

Breast cancer

Status:

Results

Phase:

Phase 3

This trial looked at a type of hormone therapy called an aromatase inhibitor. The researchers wanted to find out if taking it for 2 weeks before and 2 weeks after surgery helps postmenopausal women with breast cancer.

This trial was open for women to join between 2008 and 2014. The results were published in 2020. 

Cancer Research UK supported this trial. 

More about this trial

The first treatment for early breast cancer is usually surgery. The surgeon sends the cancer to a lab to check if it has many hormone receptors. Cancers that do are called hormone receptor positive breast cancer. You have hormone therapy as part of your treatment if you have a hormone receptor positive breast cancer. Most women have hormone therapy for at least 5 years. This helps to reduce the risk of breast cancer coming back.

Aromatase inhibitors Open a glossary item are a type of hormone therapy for women who have gone through the menopause Open a glossary item. In this trial, doctors wanted to find out if having an aromatase inhibitor for 2 weeks before and after surgery reduced the risk of their breast cancer coming back even more. The women also had standard hormone therapy for at least 5 years following surgery.

The researchers also looked at testing the cancer cells to see if there are any changes after a short course of hormone therapy. In the future, this may help doctors to work out which treatment is best for each individual patient. The aims of the trial were to:

  • see if 4 weeks of an aromatase inhibitor at the time of surgery reduced the risk of early breast cancer coming back
  • find out if testing the cancer cells after 2 weeks of hormone therapy helped to predict if a woman will do well on standard hormone therapy after surgery 
     

Summary of results

The trial found that starting an aromatase inhibitor slightly earlier had no additional benefits than having standard hormone therapy for 5 years after surgery.

But the changes seen in the cancer tissue identifies those who do well having the standard care of aromatase inhibitors for 5 years after surgery. And those whose results suggests they might benefit from having more treatment such as being in a clinical trial.   

About this trial
This was a phase 3 trial. 4,480 women took part. After their surgery every woman had an aromatase inhibitor as standard hormonal treatment. 

It was a randomised trial. There were 2 groups. Neither the women nor their doctor chose which group they were in. 

  • 2,976 women had 2 weeks of an aromatase inhibitor before and after their surgery 
  • 1,504 women didn’t have an aromatase inhibitor therapy 2 weeks before and after their surgery


The trial took tissue samples (biopsies Open a glossary item) before and after surgery to look for a protein in the cells called Ki67. They used this as a biomarker Open a glossary item to find out how well treatment was working. 

Results
Everyone had an aromatase inhibitor for at least 5 years after their surgery. The trial team have the results for 5 years of follow up. They looked at whose cancer had come back in each group. Of the 4,480 women, 434 women had their can come back. This was:

  • 280 women who had an aromatase inhibitor 2 weeks before and after surgery
  • 154 women who didn’t have an aromatase inhibitor 2 weeks before and after surgery

Samples
The team compared the level of Ki67 in the tissue samples before surgery and after surgery. They graded it as either low or high.

Women with low levels of Ki67 in the cancer tissue at the time of diagnosis and after 2 weeks of an aromatase inhibitor had a low risk of their cancer coming back when prescribed standard care of treatment.


Woman with high levels of Ki67 at diagnosis and after 2 weeks of hormone therapy had a higher risk of their cancer returning and they would most likely benefit from further treatment or going into clinical trials. Open a glossary item

There was a group of women who had high levels of Ki67 at diagnosis that had reduced after 2 weeks of an aromatase inhibitor before surgery. The team found they had:

  • a higher chance of their cancer coming back than women with a low Ki67 at diagnosis and after an aromatase inhibitor
  • a lower chance of their cancer coming back than women with a high Ki67 at diagnosis and surgery

Researchers concluded that women whose level of Ki67 changed from high to low after 2 weeks of an aromatase inhibitor did well having the standard hormone therapy after their surgery. But this could depend on other features of their cancer for example is it fast growing or not (the grade Open a glossary item of their cancer). 


Conclusion
The trial team concluded that having an aromatase inhibitor for 2 weeks before and after surgery didn’t change the risk of breast cancer coming back. But the results showed that having an aromatase inhibitor before surgery and testing for Ki67 might help to work out what treatment women need after surgery. 

This testing can reassure women who are likely to do well on standard hormone therapy after surgery. And can pick out those women who are at a high risk of their cancer coming back and who could benefit from additional treatment. The team expect that Ki67 testing will become a part of routine practice in the NHS. 

Where this information comes from    
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (peer reviewed Open a glossary item) and published in a medical journal. The figures we quote above were provided by the trial team who did the research. We have not analysed the data ourselves.

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

Professor Ian Smith

Supported by

Cancer Research UK
The Institute of Cancer Research (ICR)
The Royal Marsden Hospital NHS Foundation Trust
NIHR Clinical Research Network: Cancer

Other information

This is Cancer Research UK trial number CRUK/07/015. 

Freephone 0808 800 4040

Last review date

CRUK internal database number:

1002

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

Caroline took part in a clinical trial for breast cancer

“I had treatment last year and I want to give something back.”

Last reviewed:

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