This chapter focuses on the topic of screening, particularly the issues that need to be considered when making a decision to screen an older person for cancer. This decision highlights many of the special philosophical and practical challenges inherent in recommending preventive services to older persons. One obvious challenge to recommending cancer screening (and many other preventive services) to older adults is that few studies of preventive interventions have enrolled persons older than age 75 years. The absence of age-specific data requires clinicians to extrapolate data about the effectiveness of screening in younger persons and apply it to older persons. Furthermore, even if trials suggest that the effectiveness of screening is similar in younger and older populations, challenges remain about how to apply data from trials to an individual older person. Trials show the average effectiveness of an intervention, but they generally do not address individual patient characteristics, such as comorbid conditions or functional status, which may change the likelihood of receiving benefit or harm from screening. Given these challenges, the need to individualize screening decisions is especially important for older people, because individuals become increasingly unique in their particular combination of health, function, remaining life expectancy, and values with advancing age.
The important issues that need to be considered when making individualized screening decisions in elderly persons are not fully addressed by current guidelines. Although many screening guidelines that used to recommend upper age limits for stopping screening are now recommending screening an older person if the individual has a “reasonable life expectancy,” current guidelines offer little guidance about how to estimate life expectancy or how patient preferences should factor into screening decisions. This chapter outlines a systematic framework for individualizing cancer screening decisions in older adults that includes consideration of an individual's life expectancy and the individual's preferences regarding the potential benefits and harms of screening (Figure 14-1).
The benefits and harms that need to be weighed when making informed cancer screening decisions. Patient preferences act like a moveable fulcrum of a scale to shift the magnitude of the benefits or harms needed to tip the decision toward recommending the screening test (net benefit likely) or recommending against the screening test (net harm likely). NNS, number needed to screen to prevent one cancer-specific death.
Like many medical decisions, informed screening decisions are best made by using quantitative estimates of life expectancy and screening outcomes to anchor decisions, tempered by qualitative consideration of how an older person values the potential benefits and harms of screening. While potential benefits of screening include increased survival, this should be balanced against the potential harms of screening, which encompass adverse effects on survival, comfort, function, and psychological well-being emanating from all procedures that result from screening. For older patients who are bothered by the discomfort and risks of screening tests, the decrease in quality of ...