New Benefits Found With Annual Mammograms

They can detect smaller tumors, sometimes avoiding mastectomy

(HealthDay is the new name for HealthScoutNews.)

MONDAY, July 28, 2003 (HealthDayNews) -- As the debate over the value of mammography continues, a new study has surfaced in favor of regular screening: Mammograms not only find tumors earlier, they can also increase the chance for breast-conserving treatment.

Reporting in the September issue of Cancer, researchers from the Fox Chase Cancer Center in Philadelphia offer new evidence that regular mammogram screening lets breast cancers be discovered at an earlier, and smaller, stage -- even in women as young as 40. And doing so appears to impact treatment, helping women avoid mastectomy and keep their breast.

"Because there continues to be much controversy over the older, mostly European mammography studies, the goal of our research was to confirm findings about mammography in a modern population in a modern hospital setting, using modern equipment," says study author Dr. Gary Freedman, a radiation oncologist at the Fox Chase Cancer Center.

While in the past some mammography studies have shown regular screening could lead to early tumor detection, Freedman says the new study goes one step further in two different areas.

"First, we showed that this is true in women aged 40 to 49. And second, we were able to show that in the event a breast cancer was discovered, women who had frequent mammograms were far more likely to undergo breast-conservation therapy -- something other studies have not documented," Freedman says.

For breast surgeon Dr. Kimberly Van Zee, the study gives scientific credence to what she says doctors have intuitively known for a long time.

"Many of us always believed that regular mammograms help find cancers earlier and at a smaller size, and that doing so results in not only saving a woman's life, but saving her breast," says Van Zee, of Memorial Sloan-Kettering Cancer Center in New York City. This study is important, she says, because it backs up intuitive thinking with hard science.

"If offers immediate results and immediate conclusions -- women who underwent regular mammogram screening were more likely to have a lumpectomy [instead of mastectomy]. And that is an important scientific validation," Van Zee says.

What's more, she says, because finding tumors early is more likely to increase survival rates, this study helps draw the connecting line between regular mammograms and surviving cancer.

"It doesn't prove that, but it implies that, and this is an important point in this research," Van Zee says.

The study involved 1,591 women, aged 40 to 92, diagnosed with breast cancer between 1995 and 2001. After diagnosis, the women were divided into three groups: one had no previous mammogram (192 women); one 2 had a mammogram less than every year (695 women); and one had a mammogram at least once a year or more (704 women).

Doctors then examined the medical charts drawn up at the time of diagnosis. They noted specific information on tumor size and classification (indicating the severity of the cancer), as well as whether any lymph nodes were involved in the disease process. In addition, the researchers also noted how many women had breast-conservation therapy (a lumpectomy) and how many had a mastectomy.

The final step was cross-referencing these findings with the earlier information on the frequency of mammography.

The end result: Including women from all age groups, those who had mammograms most frequently (yearly or more often) had tumors under 1 centimeter in size 23 percent of the time, while those who never had a mammogram had small tumors only 8 percent of the time. Those who had mammograms yearly or less often had small tumors 20 percent of the time.

In addition, 56 percent of the patients who had frequent mammograms had tumors classified as early cancers, compared to just 32 percent of the women who never had a mammogram.

Finally, 61 percent of women who received frequent, regular mammograms received a lumpectomy, with 28 percent requiring mastectomy (11 percent had other treatments, including chemotherapy, radiation or no treatment). In the group that had no previous mammograms, lumpectomy was performed in 41 percent of patients, while 41 percent had mastectomy and the rest, other treatment combinations.

While most of the statistical data also held true for women between 40 and 49, there was less of a difference in their lumpectomy versus mastectomy rates. Instead of a statistically significant difference, the study showed only a trend toward breast-conservation therapy in this group.

Freedman says several reasons may be behind this portion of the finding, including a much smaller group of women with cancer in this age category.

More information

To learn more about the benefits of mammography, visit the Radiological Society of North America or the National Library of Medicine.

SOURCES: Gary Freedman, M.D., radiation oncologist, Breast Evaluation Center, Fox Chase Cancer Center, Philadelphia; Kimberly Van Zee, M.D., breast surgeon, Memorial Sloan-Kettering Cancer Center, New York City; September 2003 Cancer, online July 28, 2003
Consumer News