Mammograms Reduce Breast Cancer Death Rates

By Margarita Nahapetyan

A large U.S study shows that women who never got their mammograms done are far more likely to die of breast cancer when compared to women who undergo regular screening mammograms.

After a thorough investigation, the academics at Harvard medical School came to the conclusion that 75 per cent of the women in the study who died due to breast cancer had never received a single mammogram, or were diagnosed after their very first mammogram. And only 25 per cent of the women in the study who died due to breast cancer underwent more than one mammogram screening. A mammogram is an X-ray of the breast that can detect cancerous tumors before they grow large enough to feel, and potentially before they start spreading.

"The most effective method for women to avoid death from breast cancer is to have regular mammographic screening," said a lead author of the study, Dr. Blake Cady, MD, emeritus professor of surgery at Cambridge Hospital Breast Center and Harvard Medical School in Massachusetts. Dr. Cady added that women who are in screening programs have only a 4.7 per cent mortality rate, and women who are not screened have a 56 per cent mortality rate.

In their study, the investigators examined nearly 7,000 women who were diagnosed with breast cancer in Massachusetts between 1990 and 1999. According to the survey, 80 per cent of the women had regular mammograms, defined as at least one screening mammogram every year. The results revealed that for the period of the next thirteen years, there were 461 deaths due to breast cancer; 75 per cent (345 deaths) were among women who did not receive regular mammograms and 25 per cent (116 deaths) were among women who underwent regular screenings.

The experts then extrapolated their findings to the more than 192,000 women who will be diagnosed with invasive breast cancer in the Unites States in 2009. It is estimated that, overall, fifteen per cent of these women will die over the next thirteen years, says Dr. Cady. However, he added that when looked at by their mammogram history, only 5 per cent of those who were regularly screened are expected to die by 2022. On the contrary, 56 per cent of the women who did not undergo regular mammogram screening are expected to die over the same period of time - a rate similar to 1970, before the widespread use of mammography, Dr. Cady says.

In the past years, there has been some debate about the value and benefits of mammogram screenings. Most cancer societies as well as many governments and health authorities strongly recommend that women be screened on a regular basis but a few studies have demonstrated that mammograms may detect many false positives which means that a woman does not have a tumor but may undergo more testing, involving worry and perhaps a biopsy. Dr. Cady's response to this is: "When you look at the huge reduction in deaths that can be avoided by mammography, concerns about false-positives and having to undergo biopsies seem minor."

The results of the study were presented at a news conference with the American Society of Clinical Oncology in advance of the 2009 Breast Cancer Symposium in San Francisco.