Breast Density – The Problems with lack of Awareness

As we approach the second annual World Dense Breast Day and Breast Cancer Awareness month, LDA Research is conducting a study about women with dense breast tissue and their mammogram experiences in the US.
Here in the UK, Clare Cowhig shares her own experience of this condition, and how she is campaigning to increase breast density awareness, and help prevent unnecessary patient deaths.

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Her journey has led her to discover that women at moderate or high risk of getting breast cancer appear to be less protected than those at average/population risk. Even though family history is a significant factor, it wasn’t until she found out about her dense breast tissue, that she discovered the warnings that it could mask tumours on mammogram hidden in the NICE guidance.
Back in March 2018, when she was 50, Clare discovered an unusually thickened area on her right breast high up near her clavicle whilst showering. Her mother had breast cancer a second time the year before, and so Clare decided not to wait for the referral from her GP and instead went private.

Her sonographer said during the ultrasound that Clare had the densest breast tissue she had ever seen and questioned why she had not been having MRIs. This was the first time she found out about the issue of breast density.

The sonographer explained to Clare that cancer shows up as darker areas on ultrasounds, but on a mammogram both tumours and fibroglandular tissue show up as white. The more fibroglandular tissue, the denser the breast, and the greater the areas of white are seen. Cancers can be hidden or missed in breasts with dense tissue breast on mammograms. MRI and ultrasounds can be more effective at picking up tumours. Clare was told that two areas warranted further investigation.

She went back to the hospital where she had been having annual mammograms since the age of 41, as she had significant family history of breast cancer, although there was no identified gene mutation. She saw a breast surgeon who felt the thickened area and said it felt suspicious and sent her for mammograms. These showed nothing, and Clare asked about breast density, and the surgeon agreed that she did indeed have dense breasts.

The surgeon demonstrated what it was like trying to find a tumour in dense tissue, by rolling a piece of white tissue paper into a ball, and placing it on a piece of plain paper. It is like looking for a snowflake in a snowstorm. Due to her dense tissue Clare was sent for additional ultrasounds, and later a breast MRI, which showed possible tumours in both breasts. Biopsies confirmed she had synchronous bilateral breast cancer.

‘I underwent a breast preserving surgery known as a bilateral mammoplasty to remove two tumours. Unfortunately the pathology showed they were both invasive ductal carcinomas (IDC) and oestrogen positive ER+, Her2-. The one on the left was 2cm with a further area of 0.5cms in situ disease (DCIS). The one on the right was 5.2cms and further areas of cancer still remained. I had to undergo another operation but unfortunately, more areas of cancer were found scattered throughout my breast so I was advised to have a mastectomy.

‘As my tumours never showed up on mammograms even when they checked the imaging against the MRI scan, I was told that I could consider a double mastectomy as they were not sure how they would continue to screen my left breast in the future. Due to my relatively young age, the size of my tumour on the right and the bilateral nature of my disease, I was advised to have chemotherapy before my surgery. I agreed, and underwent five months of gruelling chemo, which I had to finish early because the drugs caused permanent nerve damage to my toes and feet.’

Clare then transferred to a specialist cancer treatment hospital where she had a double mastectomy and immediate reconstruction. When the pathology came back, it showed that she still had some in situ disease in the left breast, so she was glad that she had opted to have both breasts removed.

Thankfully Clare’s treatment has been successful and she is currently what her hospital refer to as NED – No Evidence of Disease.
‘To be honest it all felt so unnecessary. I do remember asking the team at the Family History Clinic what the point of me having more frequent and earlier screening was, if it wasn’t to catch any breast cancer at the earliest stage and smallest size possible!
‘I had annual mammograms for eight years, and an ultrasound in 2009 and 2017 but these were always reported as clear and I had no reason to query this. Following my chemotherapy, I put a complaint into the hospital, as I wanted to know how such extensive disease could be missed on my mammograms. I asked to receive a copy of my medical file, and was shocked to discover that each and every one of the reports written following my annual mammograms and put into my medical file, stated that a heterogeneously or/extremely dense breast pattern was seen. This information was never shared with me. I wanted to know why I had never been told I had dense breasts and that this could affect the sensitivity of mammogram. Their response was that I was only ever entitled to mammograms on the NHS, and that women were not routinely told their breast density, or that dense breasts raised the risk of developing breast cancer and tumours being masked on mammogram.

‘I also discovered that my screening was not part of the NHS Breast Screening Programme, but came under the NICE Clinical Guidance 164 Familial History of Breast Cancer Pathway.’

Clare then took her complaint to the Parliamentary and Health Service Ombudsman (PHSO) and discovered that the NICE Guidance 164 contained the following statement: 1.6.18:
Before decisions on surveillance are made, discuss and give written information on the benefits and risks of surveillance, including:
* the possibility that mammography might miss a cancer in women with dense breasts and the increased likelihood of further investigations [2013]

The PHSO undertook two investigations and whilst the second agreed the hospital should have been given the information about the chance of mammograms missing cancers in dense breasts Clare had suffered no injustice as the hospital wouldn’t have been able to screen her any other way apart from mammograms even if she’d been told. Therefore no apology or further action need be taken. 

She asked the PHSO for a review of the investigation as, ‘I pointed out that I couldn’t make an informed decision when agreeing to screening by mammography alone without the breast density information, and even if I couldn’t get mammograms or screening on the NHS I could have had them privately and maybe my tumours could have been found earlier.’  

Clare recently heard back from the PHSO and they apologised that both investigations had contained mistakes. They agreed that her screening hospital should have communicated with her that she had dense breast tissue which raised the risk of developing cancer and could potentially hide any tumours. She received an apology from the Medical Director of the screening hospital and evidence that women screened there on the Familial History Pathway are now provided with the information stated in the NICE Clinical Guidance 164. 

‘Unfortunately, the PHSO stated they couldn’t robustly say my tumours could have been found any earlier as I couldn’t prove what I would have done, screening wise, in hindsight and what this would have found. Whilst, it is likely something would have been seen on MRI in the nine months following my clear mammogram/ultrasound it cannot be proven. However, I still believe that my tumours could have been found earlier and I would have needed less extensive treatment and surgery if they had been found at a smaller and earlier stage.’

Clare believes ALL women should be told about the issues surrounding dense breast tissue and, if they wish, be told their own breast density. ‘I would urge women to become their own advocates and find out what they can about breast density and, if appropriate and they wish to know it, find out if they have dense breasts following a mammogram.
‘In terms of advice, I would signpost women to which provides scientifically verified information regarding breast density, and how different countries screen for breast cancer and whether they provide information to their patients about dense breasts and if they provide additional screening.’

She was recently invited to join the Patient Advisory Group for by JoAnn Pushkin who has pushed for breast density education in the US. The FDA recently announced that by the end of 2024, all women will be told if their breasts are dense or not dense following a mammogram.

‘I would tell women in the UK to discuss with their healthcare providers whether supplemental screening by whole breast ultrasound and/or MRI might be recommended in their circumstances. This would be dependant not only on their breast density but their family history and other risk factors.’

Clare will be continuing her work on ensuring women in England, who are on the NICE CG164 familial history pathway, are receiving the information about dense breasts to which they are entitled. She recently met with the Chair of the All Party Parliamentary Group on Breast Cancer and put forward the need for NICE guidance for those at moderate/high risk to be followed in full, including providing information to patients that mammography can miss cancer in dense breasts. ‘With many others, I also requested that the screening of those at moderate or high risk, and not just those at very high risk, be incorporated into the NHS Breast Screening Programme and therefore subject to the scrutiny of the Screening Committee.’

As it stands there is no overarching body which can determine when or how women at moderate/high risk are being screened and what information they are being given about breast density. Clare also discovered that women on NICE CG164 are not entitled to Duty of Candour, unlike those on the NHS Breast Screening Programme. Such inconsistencies can lead to inequalities and run the risk that some patients on the Familial History Pathway will have worse outcomes than others. 

Clare, now a Breast Density Matters Ambassador, would like people to consider signing the petition started by Cheryl Cruwys, the founder of BreastDensityMatters UK, asking for the government to provide breast density awareness and education.

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