Leading the Way in Breast Cancer Screening and Prevention

Breast cancer remains an active topic for generalist research, with four articles in this issue related to breast cancer screening and prevention. This level of activity reflects both the substantial burden of the disease in the United States and the growing realization that breast cancer screening and prevention is in a time of transition.

Screening mammography was demonstrated to reduce the risk of breast cancer death in the early 1980s.¹ Within the next several years, advisory organizations issued statements that all women 50 years of age and older should undergo annual screening mammography. Although controversy about the benefits and risks of screening mammography continued within the medical literature, public health campaigns largely overlooked this debate. The public message, that screening mammography saves lives and all women should get screened, became so imbued in American life that attempts to introduce uncertainty were considered misleading and potentially dangerous.² A large proportion of clinical and research efforts to reduce breast cancer mortality became devoted to achieving 100% mammography adherence.

Over the last 10 years, several developments have begun to challenge this absolutist approach. The identification of BRCA1 and BRCA2 rekindled interest in individual breast cancer risk prediction, emphasizing that risk varies substantially among women currently undergoing annual mammography screening.³ Tamoxifen was demonstrated to reduce the incidence of breast cancer by 47% and was approved by the FDA for breast cancer risk reduction.⁴ Preliminary data about the sensitivity of breast MRI in high-risk women increased optimism about new screening modalities.⁵ At the same time, evidence accumulated about the limitations of screening mammography, including the risk of false positive tests and the relatively modest impact on breast cancer mortality.⁶ Furthermore, belief in early detection became tempered by evidence that self-breast examination did not reduce breast cancer mortality and that a significant proportion of breast cancer may be systemic before it could be detected by current imaging modalities.^7,8 By 2004, an absolutist focus on screening mammography has become increasingly challenged by a broader, more relativistic view of breast cancer screening and prevention, where multifaceted risk reduction strategies are tailored to a woman's individual characteristics and mammography is only one, potentially optional, part of a pluralistic approach.

The articles in this issue of the Journal of General Internal Medicine provide interesting glimpses into this transition. Poon et al. demonstrate that a third of women do not undergo short-term screening follow-up or surgical evaluation after a marginally abnormal mammogram reading.⁹ In the more absolutist tradition, the authors place this finding within the context of 100% adherence to a Harvard guideline rather than the complex nature of decisions about marginally abnormal mammograms where less than 3% of women eventually prove to have breast cancer. Wee et al. also examine barriers to mammography screening, focusing on the relationship between obesity and mammography adherence.¹⁰ However, when this relationship is found to differ between black and white women, the authors suggest that preference may contribute to differential rates of mammography screening, a more relativist explanation. Moving even further from the absolutist approach, Haas et al. demonstrate that physicians tailor their recommendations for a wide range of breast cancer risk reduction interventions to a woman's breast cancer risk.¹¹

A broader, more relativistic approach to breast cancer screening and prevention offers several potential benefits. Placing mammography within a larger risk reduction armamentarium can reduce the pressure on this imperfect but widely valued test.¹² Tailoring risk reduction strategies can target intensive interventions to women at higher risk and spare cost and complications in women at lower risk. A more relativistic approach is consistent with the growing emphasis on shared decision making and cultural sensitivity in medicine. Perhaps most importantly, a broader approach is necessary to ensure the adoption and diffusion of the substantial advances in prevention, screening, and risk assessment that have occurred in the last 10 years and will occur in the future. Despite these potential benefits, times of transition are stressful. Many things will need to happen to realize the promise of a broader view of breast cancer risk reduction. Some of these include:

1. Patients and physicians need intelligible and nonthreatening information about the limitations of early detection and their actual risk of developing cancer. As demonstrated by Davids et al. in this issue, most women vastly overestimate their numeric risk of breast cancer.¹³ This information should be placed within the context of a multifaceted approach to breast cancer risk reduction so that women do not feel abandoned and physicians and policy makers can accept that some women may choose less aggressive strategies than current screening recommendations. Gil Welch's forthcoming book Should I Be Tested for Cancer? Maybe Not and Here's Why offers an important tool in this area and should be widely recommended.¹⁴

2. Advisory organizations such as the American Cancer Society and the United States Preventive Services Task Force have an important opportunity to redefine their role in cancer risk reduction. Although absolutist, population-based recommendations are unlikely to be sustainable in the future, the need for guidance by trusted sources has never been greater. Purely relativist recommendations that skirt this need by placing the decision solely between an individual patient and physician are neither popular with the general public nor useful for physicians. New areas, such as the development and dissemination of up to date information and tools for tailoring recommendations, should be considered.

3. Generalist research has an unparalleled potential to define and answer the challenges posed by this new paradigm. Moving from population-based recommendations for annual mammography screening to individualized strategies for breast cancer risk reduction will raise significant issues for primary care practice, physician-patient communication, and quality assessment. As evidenced by the articles in this issue, generalism is uniquely positioned to guide this transition and must continue to lead the way.