ACS updates breast cancer screening guidelines.

Abstract

Women at average risk of developing breast cancer should begin regular screening with mammography at age 45 years and transition to screening every 2 years starting at age 55 years, according to an updated screening guideline from the American Cancer Society (ACS).1 The new guideline supports informed decision making for women aged 40 to 44 years, who should have the option of beginning screening early, and for women aged 55 years and older, who should have the option to continue screening every year. Kevin Oeffinger, MD, chair of the breast cancer guideline panel and a family physician at Memorial Sloan Kettering Cancer Center in New York City, notes that the recommendations are made with the intent of maximizing reductions in breast cancer mortality and years of life saved while also considering the need to minimize the harms associated with screening. The guideline relies on the best evidence to provide new, more precise guidance that takes into account a woman's age, health, and personal values and preferences, according to Elizabeth Fontham, MPH, DrPH, founding dean of the School of Public Health at the Louisiana State University Health Sciences Center in New Orleans and chair of the ACS Cancer Screening Guideline Development Group. She adds that the evidence shows that although there are some benefits from mammography screening starting at age 40 years, the benefits more clearly outweigh the harms starting at age 45 years and older. Nevertheless, some women may wish to begin screening at age 40 years and should be given that opportunity. The guideline was developed by the ACS Cancer Screening Guideline Development Group, a panel of generalist clinicians, biostatisticians, epidemiologists, economists, and patient representatives. The panel commissioned a systematic review of the evidence by an independent center to inform the recommendations process. The panel concluded that the harms from false-positive results are somewhat greater for women aged 40 to 44 years compared with women in older age groups. The option of screening every 2 years for women beginning at age 55 years is based on the fact that postmenopausal breast cancers tend to develop more slowly than those developing before menopause. The panel also notes that efforts currently are underway to reduce false-positive results, including studies to improve the quality of mammography interpretation. Tomosynthesis, also known as 3-dimensional mammography, may improve outcomes while reducing false-positive findings, but there were too few data available at the time to include comparisons with 2-dimensional mammography. Molecular biomarkers may help to better predict disease progression, which could reduce the likelihood of overtreatment. In addition, barriers to quality screening still exist for low-income, uninsured women. Furthermore, the evidence did not demonstrate a benefit from routine clinical breast examination, whereas it did indicate moderate evidence that performing clinical breast examination along with mammography increases the rate of false-positive findings. Therefore, the panel did not recommend it, although they did mention the potential for these examinations to be helpful in low-resource settings outside the United States in which mammography screening is not feasible.