“I had treatment last year and I want to give something back.”
A study looking at the genetics of ductal carcinoma in situ (ICICLE)
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This study was to find genes that might increase the risk of ductal carcinoma in situ (DCIS).
Cancer Research UK supported this study.
More about this trial
In this study, the researchers looked at the genes of a large number of women who had been diagnosed with DCIS. They found out more about their family history to see if any of their relatives had also had DCIS or breast cancer.
The aims of the study were to:
- identify genes that might cause DCIS or increased the risk
- try and identify which women with DCIS were more likely to develop invasive breast cancer if DCIS wasn’t treated
Summary of results
The study team found this study provides the strongest evidence so far that DCIS like invasive breast cancer can be genetic. And that many of the genetic changes that cause invasive breast cancer also cause DCIS.
Researchers looked at the data of 38 studies of breast cancer and DCIS. From this there were:
- 5,067 examples of DCIS (the majority of which came from the ICICLE study)
- 24,584 examples of invasive breast cancer
- 37,467 examples where there was no DCIS or breast cancer (control group)
The team looked at over 200,000 genetic changes in all the samples. They found that most of the 76 known genetic changes that increase the risk of invasive breast cancer also increase the risk of DCIS.
The researchers also looked at the examples according to whether they had receptors for the hormone oestrogen (ER positive). They found that there was a link between the genes that increase the risk of ER positive breast cancer and ER positive DCIS.
The study team didn’t find any genetic changes that only increased the risk of DCIS and not invasive breast cancer.
The team concluded that this study gives the strongest evidence to date that there is a shared genetic cause of DCIS and invasive breast cancer. Studies with larger numbers need to be done to determine if there are particular genetic changes that increase the risk of DCIS and not invasive breast cancer.
We have based this summary on information from the research team. The information they sent us has been reviewed by independent specialists (
How to join a clinical trial
Dr Rebecca Roylance
Dr Elinor Sawyer
Cancer Research UK
Breast Cancer Now
Experimental Cancer Medicine Centre (ECMC)
NIHR Clinical Research Network: Cancer
This is Cancer Research UK trial number CRUK/08/046.