IBIS II breast cancer trial

This page tells you about IBIS II (IBIS 2) trial for breast cancer. This trial is following on from the IBIS I (IBIS 1) prevention trial. There is information on

What the trial is about
Who can take part in the trial
Who can't enter the trial
If you would like to join the trial

The IBIS 1 prevention trial looked into using a hormone therapy called tamoxifen to prevent breast cancer in women at high risk of getting the disease. This trial found that the number of breast cancer cases was lowered by a third in the group of women taking tamoxifen to try to prevent breast cancer. IBIS 2 is looking at using another hormone treatment - anastrazole.

There are two main parts to the IBIS 2 trial.

IBIS 2 (prevention) is looking at preventing breast cancer.
IBIS 2 (DCIS) is looking at treating DCIS

This page is about the IBIS 2 (prevention) trial, which is testing a hormone drug called anastrozole to see if it can prevent breast cancer in women who are at high risk of getting this disease. There is more information about IBIS-2 (DCIS) on our clinical trials database.

The entry conditions for this trial are very detailed. But we thought it might be helpful to put them up in full so that women who are interested can see for themselves if they can join.

Doctors call the entry conditions for a clinical trial the eligibility criteria. For the IBIS 2 trial, these are divided into groups according to your age. The eligibility criteria refer to 1st and 2nd degree relatives. A 1st degree relative includes mother, sister or daughter. A 2nd degree relative includes grandmother, aunt or niece.

There are also exclusion criteria which give details about who cannot take part.

Remember - all women in the IBIS trial must be post menopausal. That means your periods have stopped naturally because you have reached the 'change of life'. Or that you have had to have your ovaries removed for some reason.

The IBIS II entry criteria for women are set according to the following

Between 40 and 44
Between 45 and 59
Between 60 and 70
Other women who may not fit into any of the categories listed

If you are between 40 and 44

You must fit into one of these categories to join. You have

At least two 1st degree relatives with breast or ovarian cancer diagnosed by the age of 50
At least one 1st degree relative with breast cancer diagnosed in both breasts with the first cancer diagnosed at age 50 or less
At least two 1st or 2nd degree relatives with ovarian or breast cancer (if both are 2nd degree and they are on opposite sides of your family, one must have been diagnosed before age 50)
No children or your first child was born after you were 30 and you have a 1st degree relative with breast cancer who was diagnosed with breast cancer at age 40 or less
Had a breast biopsy that was benign but showed overgrowth of cells (proliferative disease) and you have a 1st degree relative with breast cancer who was diagnosed at age 40 or less
Shadows (opacity) on at least 50% of your mammogram and have not taken HRT in the last 3 months
Had LCIS
Had a DCIS treated by mastectomy within the last 6 months
Had a breast lump that showed atypical ductal or lobular hyperplasia

If you are between 45 and 59

You must fit into one of these categories to join. You have

A 1st degree relative with breast cancer diagnosed by the age of 50
A 1st degree relative with breast cancer in both breasts
At least two 1st or 2nd degree relatives with breast or ovarian cancer (if both are 2nd degree and they are on opposite sides of your family, one must have been diagnosed before age 50)
No children or your first child was born after you were 30 and you have a 1st degree relative with breast cancer
Had a breast biopsy that was benign but showed proliferative disease (where there is a overgrowth of cells) and you have a 1st degree relative with breast cancer
Shadows (opacity) on at least 50% of your mammogram and have not taken HRT in the last 3 months
Had LCIS
Had a DCIS treated by mastectomy within the last 6 months
Had a breast lump that showed atypical ductal or lobular hyperplasia

If you are between 60 and 70

You must fit into one of these categories to join. You have

A 1st degree relative diagnosed with breast cancer at any age
A 1st degree relative with breast cancer in both breasts
At least two 1st or 2nd degree relatives with breast or ovarian cancer (if both are 2nd degree and they are on opposite sides of your family, one must of been diagnosed before age 50)
Had your menopause after you were 55
No children or your first child was born after you were 30 and you have a 1st degree relative with breast cancer
Had a breast biopsy that was benign but showed proliferative disease (where there is overgrowth of cells) and you have a 1st degree relative with breast cancer
Shadows (opacity) on at least 50% of your mammogram and have not taken HRT in the last 3 months
Had LCIS
Had a DCIS treated by mastectomy within the last 6 months
Had a breast lump that showed atypical ductal or lobular hyperplasia

Other women may be eligible

The trial organisers are willing to consider women who don't fit into any of the categories above, but who may have an increased risk of breast cancer because of their family history.

If you think you are at increased risk of breast cancer because of your family history, you could email the IBIS 2 research team on ibis@cancer.org.uk, or write to them at

IBIS 2 Cancer Research UK Wolfson Institute of Preventative Medicine Charterhouse Square London EC1M 6BQ

Please explain your family history and remember to include your contact details.

You cannot take part in this trial if you

Are still having periods
Have breast cancer, or have had breast cancer in the past (unless you have had DCIS - see criteria for specific age groups)
Have had any cancer in the past 5 years, apart from carcinoma in situ of the cervix or a non-melanoma skin cancer
Have taken tamoxifen, raloxifene or other Selective Oestrogen Modulators (SERMs) for more than 3 months in the past
Intend to carry on taking HRT that contains oestrogen
Have had, or planning to have, surgery to lower your risk of breast cancer (prophylactic mastectomy)
Have any other serious medical condition
Have taken any trial drug in the past 3 months

First you need to check below to see if you meet the entry conditions. If you do, you can fill in the form on the IBIS II trial website. Or you could print off the form, fill it out and send it to

IBIS 2 Cancer Research UK Wolfson Institute of Preventative Medicine Charterhouse Square London EC1M 6BQ

Or if you would like to receive a leaflet in the post, you can call the IBIS-2 leaflet request line on 0800 111 4134. This is an answer machine service only, so you will need to leave you name and postal address. Alternatively, you can either