Women between the ages of 40 and 49 years who are diagnosed with breast cancer detected by mammography have a better prognosis than women whose breast cancer was found by themselves or their doctors. This is according to results of a study published in the journal Radiology.
Recommendations for annual mammographies in this age group are controversial. While the American Cancer Society and other medical organizations recommend annual screening beginning at age 40, the U.S. Preventative Services Task Force does not, because of their concern about false positive results.
Researchers at the Swedish Cancer Institute in Seattle analyzed data on 1,977 patients with breast cancer who were between 40 and 49 years and who were treated between 1990 and 2008. The researchers looked at how the breast cancer was found, the stage at which it was found, and what treatment was done as a result.
They found that physician and patient detected cancers dropped from 73 percent in all cases in 1990 to 42 percent in 2008. Mammography detected breast cancers rose significantly from 28 percent to 58 percent. In addition, the cancers were diagnosed earlier: Stage 0 diagnosed cancers increased by 66 percent from 1990, and diagnosis of stage III cancers dropped by 66 percent during the same time period.
“The objective of screening is to detect disease at an earlier, more treatable stage, which — based on our review — mammography accomplishes,” said Judith A. Malmgren, PhD, president of HealthState Consulting Inc.
Earlier detection of breast cancer also resulted in differing treatment, the researchers said. Women who had mammography detected breast cancer were generally less likely to undergo chemotherapy or a radical mastectomy, both of which are more difficult for patients than lumpectomies, said Malmgren. However, most of the stage 0 cancers that were diagnosed were ductal cancer in situ (DCIS), which is non-invasive cancer in the milk duct. Whether to treat DCIS is controversial.
The women with mammography detected breast cancer were also less likely to die, note the researchers (4 percent mammography detected versus 11 percent other detected).
