Dense breasts can nearly double the risk of breast cancer recurrence
Women aged 50 and over with breasts that have a high percentage of dense tissue are at greater risk of their breast cancer recurring, according to Swedish research presented at the eighth European Breast Cancer Conference (EBCC-8) in Vienna today.
Dr Louise Eriksson and her colleagues from the Karolinska Institutet (Stockholm, Sweden) found that women with denser breasts had nearly double the risk of their cancer recurring, either in the same breast or in the surrounding lymph nodes, than women with less dense breasts. They warn that doctors should take breast density into account when making decisions about treatment and follow-up for these women.
When a woman has a mammogram, the resulting scan gives an image of the breast that shows areas of white and black. The white areas represent the dense tissue, made up of the epithelium and stroma. The black areas are made up of fatty tissue, which is not dense. The percentage density (PD) of the breast is calculated by dividing the dense area by the area of the whole breast (dense and non-dense tissue included).
Breast density varies from woman to woman, and it also decreases with age. Dr Eriksson explained: "Density can vary greatly, even between postmenopausal women. In the group of women I studied, those with the lowest percentage density had breasts that were less than one percent dense, whereas those with highest PD had 75-80% dense breasts. The mean average PD was 18%. However, density does decrease with age. Studies have shown a decrease by approximately two percent per year. The largest decrease is seen at menopause when PD decreases by approximately 10%."
The researchers studied the mammograms and outcomes for 1,774 post-menopausal women who were aged 50-74 and who were part of a larger study of all women with breast cancer diagnosed between 1993-1995 in Sweden.
"We found that if you have a PD at diagnosis of 25% or more, you have an almost two-fold increased risk of local recurrence in the breast and surrounding lymph nodes than women with a PD of less than 25%. However, density does not increase the risk of distant metastasis and has no effect on survival. We also see that although mammographic density is one of the strongest risk factors for breast cancer it doesn't seem to influence tumour development in any specific way; for instance, it isn't more associated with oestrogen receptor positive tumours than oestrogen receptor negative tumours, but seems to act as a general stimulator of tumour development," said Dr Eriksson, who is a PhD student at the Karolinska, as well as a physician at the Stockholm South General Hospital.
"Our study shows that breast density before or at diagnosis should be taken into account even after diagnosis, for instance, when deciding on adjuvant treatment and follow-up routines; perhaps women with dense breasts should be followed more frequently or for a longer period of time in order to quickly spot any local recurrence.
"As far as screening programmes are concerned, it is already known that breast density is a risk factor for the occurrence of breast cancer and that it decreases the sensitivity of mammograms. Our study confirms the importance of taking breast density into account in the screening setting."
Until now, little was known about the association between density, tumour characteristics and prognosis once cancer had occurred, and results were conflicting. This study is important because of its size and detailed information on each woman. "This is one of the largest studies to date studying mammographic density, tumour characteristics, and prognosis, including almost 50% of all Swedish breast cancer cases diagnosed 1993-1995," said Dr Eriksson.
Cancer researchers do not know why breast density is a risk factor for breast cancer. "It could simply be due to higher density being associated with more cells, which means that more cells are at risk of developing cancer," she said. "Another hypothesis is that it is the relationship between mammographic density and the stroma (which has been shown to be the main compound of mammographic density) that is central to the increase in risk. There is no leading hypothesis on why an increased amount of stroma would increase breast cancer risk, but it is known that the interaction between the epithelial cells and the stroma is crucial to the development of breast cancer. Based on the results from our study, we propose that mammographic density creates a beneficial environment for epithelial cells to transform into cancer cells; much like fertile soil giving a planted seed the needed nutrients to grow and develop."
Professor David Cameron, from the University of Edinburgh (Edinburgh, UK), and chair of EBCC-8 said: "This study raises questions about how and why the appearance of normal breast tissue on a mammogram could influence the chances of a local recurrence of breast cancer. It is, therefore, more thought-provoking than practice-changing, since it is not clear what a patient, or her physician, should do if the mammogram shows a higher density of the normal breast tissue. A number of factors are known that influence mammographic breast density, but more research is needed to know which of these, if any, is responsible for this important observation."
Provided by ECCO-the European CanCer Organisation
- Breast density tied to specific types of breast cancer Jul 27, 2011 | not rated yet | 0
- Women born to older mothers have a higher risk of developing breast cancer Feb 06, 2012 | not rated yet | 0
- Breast density linked to increased risk of subsequent breast cancer Oct 07, 2010 | not rated yet | 0
- Researchers find potential links between breast density and breast cancer risk Dec 14, 2008 | not rated yet | 0
- Breast tenderness in women getting combo hormone therapy associated with increase in breast density Oct 14, 2011 | not rated yet | 0
- Motion perception revisited: High Phi effect challenges established motion perception assumptions Apr 23, 2013 | 3 / 5 (2) | 2
- Anything you can do I can do better: Neuromolecular foundations of the superiority illusion (Update) Apr 02, 2013 | 4.5 / 5 (11) | 5
- The visual system as economist: Neural resource allocation in visual adaptation Mar 30, 2013 | 5 / 5 (2) | 9
- Separate lives: Neuronal and organismal lifespans decoupled Mar 27, 2013 | 4.9 / 5 (8) | 0
- Sizing things up: The evolutionary neurobiology of scale invariance Feb 28, 2013 | 4.8 / 5 (10) | 14
Why is zone 1 in liver more prone to ischemic injury?
12 hours ago Hi, Is it because around central vein, there is only deoxygenated blood from the vein where as in the periphery there is hepatic artery. Also why...
How can there be villous adenoma in colon, if there are no villi there
May 22, 2013 As title suggest. Thanks :smile:
How can there be a term called "intestinal metaplasia" of stomach
May 21, 2013 Hello everyone, Ok Stomach's normal epithelium is simple columnar, now in intestinal type of adenocarcinoma of stomach it undergoes "intestinal...
Pressure-volume curve: Elastic Recoil Pressure don't make sense
May 18, 2013 From pressure-volume curve of the lung and chest wall (attached photo), I don't understand why would the elastic recoil pressure of the lung is...
If you became brain-dead, would you want them to pull the plug?
May 17, 2013 I'd want the rest of me to stay alive. Sure it's a lousy way to live but it beats being all-the-way dead. Maybe if I make it 20 years they'll...
MRI bill question
May 15, 2013 Dear PFers, The hospital gave us a $12k bill for one MRI (head with contrast). The people I talked to at the hospital tell me that they do not...
- More from Physics Forums - Medical Sciences
More news stories
Even while being dragged to its destruction inside a cell, a cancer-promoting growth factor receptor fires away, sending signals that thwart the development of tumor-suppressing microRNAs (miRNAs) before it's dissolved, researchers ...
Cancer 33 minutes ago | not rated yet | 0 |
Treating pediatric leukemia patients with a liposomal formulation of anthracycline-based chemotherapy at a more intense-than-standard dose during initial treatment may result in high survival rates without causing any added ...
Cancer 4 hours ago | not rated yet | 0
Scientists have uncovered a survival mechanism that occurs in breast cells that have just turned premalignant-cells on the cusp between normalcy and cancers-which may lead to new methods of stopping tumors.
Cancer 5 hours ago | not rated yet | 0 |
Frequent heartburn was positively associated with cancers of the throat and vocal cord among nonsmokers and nondrinkers, and the use of antacids, but not prescription medications, had a protective effect, according to data ...
Cancer 5 hours ago | not rated yet | 0
Ethnic background plays a surprisingly large role in how diabetes develops on a cellular level, according to two new studies led by researchers at the Stanford University School of Medicine.
1 hour ago | not rated yet | 0 |
Finnish researchers unveiled new data Thursday to link the Pandemrix flu vaccine to a higher risk of the sleeping disorder narcolepsy in adults.
33 minutes ago | not rated yet | 0
Maintaining a heart healthy lifestyle may also help protect chronic kidney disease patients from developing kidney failure and dying prematurely, according to a study appearing in an upcoming issue of the Journal of the Am ...
3 minutes ago | not rated yet | 0
(AP)—Johnson & Johnson is developing what could eventually be game-changing treatments for depression and pain, and it's aiming to apply for approval of more than 10 new medicines by 2017, executives said Thursday during ...
23 minutes ago | not rated yet | 0
The Senate has overwhelmingly rejected an amendment allowing states to require labeling of genetically modified foods.
13 minutes ago | not rated yet | 0
A second child has contracted polio in a restive Pakistani tribal region near the Afghan border after the Taliban banned vaccinations there nearly a year ago, a UN official said Thursday.
53 minutes ago | not rated yet | 0