Disparities have a multifaceted impact in the field of oncology with adverse differences in cancer outcomes, such as mortality, morbidity, and prevalence, that often translate into health inequities.1 The contemporary understanding of disparities has expanded beyond describing racial differences and toward explaining inequities by sex, age, income, education level, geographic location, insurance coverage, lifestyle, and cultural differences. Nevertheless, even these categorizations are fluid, in that they can still be imprecise, overlapping, interrelated, and/or synergistic, representing complex relationships between sociological, biological, structural, and even policy concepts. Studies of patients with cancer highlight the associations between barriers to quality cancer care and adverse cancer outcomes, positing influences by patient, structural, socioeconomic, and healthcare access risk factors.2, 3
There is some evidence to suggest that disparities may have a unique impact in the field of radiation oncology, with differences in patient utilization of advanced radiation technologies and access to high-volume facilities.3, 4, 5 Distance from radiation facilities is a well-known risk factor for inadequate radiation oncology care.6, 7, 8, 9 Disparities in radiation treatment delivery measures, including treatment delays, breaks, and incompletion, have also been documented,10, 11 along with the uptake of newer, benchmarked practices, such as hypofractionation in early stage breast cancer.
The risk factors, mechanisms, and outcomes of disparities in radiation oncology still require additional investigations to prompt continuous improvements in multidisciplinary cancer care infrastructure and outcomes in the United States and beyond. We seek to highlight this topic with an ongoing series of articles on the impact of disparities on delivery and outcomes of radiation therapy as well as participation in research.
Footnotes
Conflicts of interest: The authors declare no potential conflicts of interests.
References
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