Monday, February 21, 2005
Mammography Tool.....
From CNN:Stats: Mammogram would cut deaths by third:
From CNN:Stats: Mammogram would cut deaths by third:
If every woman aged between 50 and 79 got a mammogram every year, it would reduce deaths from breast cancer by 37 percent, according to a new statistical tool.They would like to put their algorithm on the internet to allow women to weigh their risk about brest cancer.
Screening these women every two years would reduce mortality by 30 percent, Sandra Lee and colleagues at Harvard Medical School and the Dana Farber Cancer Institute in Boston calculated.
"Health policy makers can use this information to come up with public screening (recommendations)," Lee told a news conference at the annual meeting of the American Association for the Advancement of Science.The current recommendations are not uniform:
"An individual woman can use this to decide what is better for her. A 7 percent reduction may not be so big for some women. It may be important for other women."
The American Cancer Society recommends that women 40 and older have a mammogram every year. The National Cancer Institute also recommends starting at 40 and having one every one or two years.The American Association for the Advancement of Science has not put the text of the speech or copy of the paper on their website so I have no idea how they came to the 37% reduction in deaths from cancer. Moving along:
But the British National Health Service offers mammograms only after 50 and at three-year intervals, while other European countries often offer them every two years.
"It's clear that the more mammograms you give, the more able you are to locate disease that a person didn't know about," Zelen said in a statement.Yes, but would that correspond to an increased survival?
But more tests can lead to detection of non-cancerous lumps that must be biopsied, costing money and anxiety.Breast tissue is also more dense in younger patients, which reduces the effectiveness of mammography. Which is one reason mammograms are not offered to thirty year-olds.
Lee said her model was not meant to provide an absolute guide to whether more screening is better.
"Breast cancer in a woman in her 40s is more aggressive, so it would make sense to have frequent screening," she said -- even though breast cancer is more rare in this age group.
And because breast cancer is more common in women over 50, it could also be argued that frequent screening benefits this group, she said.
There are also more benefits to having mammograms than just saving lives, said Dr. Timothy Rebbeck of the University of Pennsylvania School of Medicine.Now we are beginning to compare apples and oranges here. The accepted indications for chemotherapy have expanded over the years to the point where a premenopausal woman with a tumor of 1cm or larger is going to be offered treatment. The threshold for post-mastectomy radiation has been lowered as well. So while the disease may be detected earlier, the therapy may still be aggressive. |
"To the degree that you can identify tumors earlier, you can be saving some costs," he told the news conference. Women can have a smaller surgical procedure and perhaps escape the need for chemotherapy and radiation.
