Defining Undertreatment and Overtreatment in Older Adults With Cancer: A Scoping Literature Review

Abstract

Purpose: The terms undertreatment and overtreatment are often used to describe inappropriate management of older adults with cancer. We conducted a comprehensive scoping review of the literature to clarify the meanings behind the use of the terms.

Methods: We searched PubMed (National Center for Biotechnology Information), Embase (Elsevier), and CINAHL (EBSCO) for titles and abstracts that included the terms undertreatment or overtreatment with regard to older adults with cancer. We included all types of articles, cancer types, and treatments. Definitions of undertreatment and overtreatment were extracted, and categories underlying these definitions were derived through qualitative analysis. Within a random subset of articles, C.D. and K.P.L. independently performed this analysis to determine final categories and then independently assigned these categories to assess inter-rater reliability.

Results: Articles using the terms undertreatment (n = 236), overtreatment (n = 71), or both (n = 51) met criteria for inclusion in our review (n = 256). Only 14 articles (5.5%) explicitly provided formal definitions; for the remaining, we inferred the implicit definitions from the terms' surrounding context. There was substantial agreement (κ = 0.81) between C.D. and K.P.L. in independently assigning categories of definitions within a random subset of 50 articles. Undertreatment most commonly implied less than recommended therapy (148; 62.7%) or less than recommended therapy associated with worse outcomes (88; 37.3%). Overtreatment most commonly implied intensive treatment of an older adult in whom the harms of treatment outweigh the benefits (38; 53.5%) or intensive treatment of a cancer not expected to affect an older adult in his/her remaining lifetime (33; 46.5%).

Conclusion: Undertreatment and overtreatment of older adults with cancer are imprecisely defined concepts. We propose new, more rigorous definitions that account for both oncologic factors and geriatric domains.

FIG 1.

Flow diagram of article inclusion in review.

FIG 2.

Graphical illustration of essential concepts of proposed definitions of undertreatment and overtreatment. (A) General graph of relationships among benefits of cancer treatment, harms of treatment, and vulnerability of older patient. Benefits of cancer treatment are a function of the effectiveness of the treatment, the aggressiveness of the cancer, and the remaining life expectancy of the patient. Harms of a particular treatment are a function of treatment intensity and adverse effects. Vulnerability is a function of geriatric assessment deficits (eg, cognitive impairment, functional dependency). As patient vulnerability increases, treatment benefits decrease and harms increase. For a given vulnerability on the x-axis, the blue shading represents a treatment where the benefits outweigh the harms (net benefit = undertreatment if not offered). For more severe vulnerability on the x-axis, the red shading represents a treatment where the harms outweigh the benefits (net harm = overtreatment if prescribed). The more intensive color shading in the next figure panels helps to illustrate net harm v net benefit for a given patient and treatment. Individual patient preferences should inform the balance between benefits and harms of a given treatment. (B) The left panel shows an example of undertreatment when considering definitive surgery in a fit older patient: A 75 year-old community-dwelling female with few comorbidities has early-stage breast cancer and values survival even with tradeoffs but is not offered definitive cancer surgery on the basis of her age alone. The right panel shows an example of overtreatment when considering definitive cancer surgery in a vulnerable older patient: A 75-year-old female nursing home resident with limited life expectancy has early-stage breast cancer and values quality of life over survival but is recommended to undergo definitive surgery that leads to an irreversible decline in function. (C) Example of undertreatment when considering variable intensities of chemotherapy in a fit patient: A 75-year-old male with intact cognitive and physical function has multiple myeloma and values survival even with tradeoffs but is treated with a lower intensity chemotherapy regimen on the basis of age alone (left panel) when a standard intensity regimen (right panel) offers greater prolongation of life. (D) Example of overtreatment when considering variable intensities of chemotherapy in a vulnerable patient: A 75-year-old male with advanced osteoarthritis and sarcopenia has gastroesophageal cancer but is prescribed a higher intensity chemotherapy regimen (left panel) when a lower-intensity regimen (right panel) offers similar survival benefit with less toxicity.