By David Liu, PHD

Tuesday Aug 28, 2012 (foodconsumer.org) -- Early research suggests high mammographic breast density increases risk of developing breast cancer.  Good news is that high mammographic breast density may not increase risk of death from the disease or even any other cause, according to a new study in the Journal of The National Cancer Institute.  The study only suggests a possibility because it was not a trial and could not estabolish a causal relation between these factors.

Gretchen L. Gierach of National Cancer Institute in Rockville, MD and colleagues found the association after analyzing data from 9232 women diagnosed with primary invasive breast cancer or breast carcinoma between 1996 and 2005 who were followed up for 6.6 years on average. mammographic density or breast density of mammograms was assessed from the breast mammographic images from the Breast Imaging Reporting and Data System (BI-RADS). 

During the follow-up, a total of 1795 women died, of whom 889 died of breast cancer and the remaining died from other causes.  After adjustment for tumor site, age at the time of diagnosis, American Joint Committee on Cancer stage, body mass index, mode of detection, disease treatment, and income, high mammographic breast density was not found associated with risk of death from breast cancer or all causes.

In groups stratified by stage and other factors, no similar association was observed except that in women with low density who were either obese or had tumors with its size greater than 2.0 cm, mammographic density has something to do with the death risk in the breast cancer patients.   In obese breast cancer patients with low density, the risk death from breast cancer was 102 percent increased, compared to those who were not obese.  In breast cancer patients who had a larger tumor,low breast density of mammograms was associated with 55 percent increased risk for the patients to die from breast cancer, compared with those with smaller tumors.

The researchers concluded "High mammographic breast density was not associated with risk of death from breast cancer or death from any cause after accounting for other patient and tumor characteristics."

Research has shown that breast cancer screening using mammography increased the diagnosis rate, but it does not cut the risk of death or early diagnosis does not reduce mortality.

Breast cancer is expected to be diagnosed in 230,000 women in the United States in 2012, according to the National Cancer Institute. The disease and complications from the disease and treatment are expected to kill about 40,000 in the same year in the U.S.

Breast cancer in many cases is preventable by following a healthy lifestyle including a healthy diet.  Vitamin D and C among other things are important in preventing the disease.  Two generally recognized risk factors for breast cancer are hormone replacement therapy adn medical radiation, which should be avoided whenever possible, previous studies suggest.