"Breast cancers in women aged  to  that are diagnosed by mammograms have a better prognosis than those detected by doctors or the women themselves a new study indicates.    They have an earlier diagnosis earlier stage better prognosis said study author Judith Malmgren an affiliated professor of epidemiology at the University of Washington School of Public Health and Community Medicine. She is also president of HealthStat Consulting Inc. in Seattle.    The new study like previous ones reignites the ongoing debate about the best age to start routine mammograms and the best screening interval. It appears in the March issue of the journal Radiology.    In  the U.S. Preventive Services Task Force issued mammogram recommendations. It recommends women aged  to  who are at average risk for breast cancer have a mammogram done every two years. It also suggests that women aged  to  at average risk discuss the pros and cons with their doctors and decide on an individual basis if and when to start screening.    Meanwhile other organizations including the American Cancer Society recommend women begin mammograms at age  and continue to have them annually.    Malmgren and her colleagues evaluated nearly  women who had breast cancer. All were aged  to  when they were treated between  and .    The researchers looked at the method of diagnosis whether by mammogram or if the cancer was found by the doctor or the woman. They also took these into account the cancers stage at diagnosis type of treatment annual followup recurrence and survival.    Over the year period the number of breast cancers diagnosed at very early stages increased  percent while the number of more advanced cancers stage  decreased by  percent.    Those whose cancers were detected by mammogram rose from  percent in  to  percent in . The number of cancers detected by doctor or patients declined from  percent in  to  percent in .    Women whose cancers were detected by mammograms were more likely than the doctor or patientdetected cancers to have lumpectomy or other breastconserving surgery  percent vs.  percent. The women whose cancers were detected by mammograms were less likely to be given chemotherapy.    While  percent of women whose cancer was found on mammogram died during a followup period that ranged from one to  years  percent of those whose cancers were found by the doctor or the women died.    When the researchers looked only at invasive cancers  percent of the women whose cancer was found on mammogram survived without recurrence at five years  percent of the other group did.    I dont think the U.S. Preventive Services Task Force is looking at the whole picture Malmgren said. They are concentrating on the harms.    Among them according to the  guidelines are falsepositives which can lead to anxiety and unnecessary biopsies.    Malmgren a breast cancer survivor says more focus should be placed on the benefit of early diagnosis because it often means less treatment is needed.    There was a decrease found in cancers being diagnosed at later stages in those whose cancers were found on mammograms. Thats where the money is Malmgren said.    Dr. Virginia Moyer chair of the U.S. Preventive Services Task Force and a professor of pediatrics at Baylor College of Medicine reviewed the study. The findings make sense she said.    They found that cancers can be detected earlier by mammogram. A screening test if it cant find something earlier than by clinical presentation is a poor test she said.    However she said the study does not provide support for all women aged  to  to have routine mammograms.    When considering its recommendation the task force took all available evidence into account including published studies Moyer noted. The data from randomized trials and modeling show there is a very modest improvement in mortality with mammograms from  to  she said.    Because it is so modest and there are risks people need to make their own decision Moyer said.    More information  To learn more about mammograms go to the U.S. National Cancer Institute.  SOURCES Judith A. Malmgren Ph.D. affiliate professor epidemiology Washington University School of Public Health and president of HealthStat Consulting Inc. Seattle Virginia Moyer M.D. chairwoman U.S. Preventive Services Task Force and professor pediatrics Baylor College of Medicine Houston March  Radiology"