主页 > 医学讨论 >
【medical-news】40-49岁妇女筛检性乳房X光摄影：美
Screening Mammography for Women 40 to 49 Years of Age: A Clinical Practice Guideline from the American College of Physicians
Amir Qaseem, MD, PhD, MHA; Vincenza Snow, MD; Katherine Sherif, MD; Mark Aronson, MD; Kevin B. Weiss, MD, MPH; Douglas K. Owens, MD, MS, for the Clinical Efficacy Assessment Subcommittee of the American College of Physicians*
3 April 2007 | Volume 146 Issue 7 | Pages 511-515
Breast cancer is one of the most common causes of death for women in their 40s in the United States. Individualized risk assessment plays an important role when making decisions about screening mammography, especially for women 49 years of age or younger. The purpose of this guideline is to present the available evidence for screening mammography in women 40 to 49 years of age and to increase clinicians' understanding of the benefits and risks of screening mammography.
Recommendation 1: In women 40 to 49 years of age, clinicians should periodically perform individualized assessment of risk for breast cancer to help guide decisions about screening mammography.
A careful assessment of a woman's risk for breast cancer is important. The 5-year breast cancer risk can vary from 0.4% for a woman age 40 years with no risk factors to 6.0% for a woman age 49 years with several risk factors (1). Factors that increase the risk for breast cancer include older age, family history of breast cancer, older age at the time of first birth, younger age at menarche, and history of breast biopsy. Women 40 to 49 years of age who have any of the following risk factors have a higher risk for breast cancer than the average 50-year-old woman: 2 first-degree relatives with breast cancer; 2 previous breast biopsies; 1 first-degree relative with breast cancer and 1 previous breast biopsy; previous diagnosis of breast cancer, ductal carcinoma in situ (DCIS), or atypical hyperplasia; previous chest irradiation (1); or BRCA1 or BRCA2 mutation (2, 3). A family history can also help identify women who may have BRCA mutations that place them at substantially higher risk for breast and other types of cancer (Table). These women should be referred for counseling and recommendations specific to this population, as recommended by the U.S. Preventive Services Task Force (USPSTF) (4). Risk assessments should be updated periodically, particularly in women whose family history changes (for example, a relative receives a diagnosis of breast or ovarian cancer) and in women who choose not to have regular screening mammography. Although no evidence supports specific intervals, we encourage clinicians to update the woman's risk assessment every 1 to 2 years.
Table. Family History Patterns Associated with an Increased Risk for BRCA1 or BRCA2Gene Mutations*
The risk for invasive breast cancer can be estimated quantitatively by using the Web site calculator provided by the National Institutes of Health (NIH) (http://bcra.nci.nih.gov/brc/q1.htm) (1). This calculator is based on the Gail model, which takes into account many of the risk factors previously mentioned. However, clinicians who use the Gail model should be aware of its limitations. Although the model accurately predicts the risk for cancer for groups of women, its ability to discriminate between higher and lower risk for an individual woman is limited (5, 6). This limitation occurs because many women have similar, relatively low absolute risks for invasive breast cancer over 5 years, which makes discrimination among levels of risk difficult for an individual woman.
Recommendation 2: Clinicians should inform women 40 to 49 years of age about the potential benefits and harms of screening mammography.
Screening mammography for women 40 to 49 years of age is associated with both benefits and potential harms. The most important benefit of screening mammography every 1 to 2 years in women 40 to 49 years of age is a potential decrease in breast cancer mortality. A recent meta-analysis estimated the relative reduction in the breast cancer mortality rate to be 15% after 14 years of follow-up (relative risk, 0.85 [95% credible interval {CrI}, 0.73 to 0.99]) (7). An additional large randomized clinical trial of screening mammography in women 40 to 49 years of age found a similar decrease in the risk for death due to breast cancer, although the decrease did not reach statistical significance (relative risk, 0.83 [95% CI, 0.66 to 1.04]) . Potential risks of mammography include false-positive results, diagnosis and treatment for cancer that would not have become clinically evident during the patient's lifetime, radiation exposure, false reassurance, and procedure-associated pain. False-positive mammography can lead to increased anxiety and to feelings of increased susceptibility to breast cancer, but most studies found that anxiety resolved quickly after the evaluation.
Recommendation 3: For women 40 to 49 years of age, clinicians should base screening mammography decisions on benefits and harms of screening, as well as on a woman's preferences and breast cancer risk profile.
阅读本文的人还阅读：
作者:admin@医学,生命科学 2010-12-18 05:11
医学,生命科学网