Racial Disparities in the Use of Radiologic Imaging for Cancer Care: A Systematic Review

From the 2021 HVPAA National Conference

Rebecca Colwell (University of Wisconsin School of Medicine and Public Health), Anand Narayan (Massachusetts General Hospital), Andrew Ross

Background

Racial disparities in cancer outcomes are well known with minorities both presenting at later stages of disease than White patients and having higher rates of mortality. This is likely multifactorial although there are multiple recent studies indicating inequities in the use of diagnostic imaging for cancer management based on patient race and ethnicity.

Objective

The aim of this study was to summarize the existing literature on disparities in the use of diagnostic imaging based on patient race and ethnicity in the setting of cancer care and to identify avenues of future research to mitigate these disparities and promote an equitable health care system.

Methods

Using key words focused on diagnostic imaging, race/ethnicity, and health disparities, we performed a systematic review of the literature in Medline, Cochrane, Web of Science, and Scopus for the years 2000 to the present. Citations were reviewed for relevance by title and abstract and then full text review. Papers were included if they compared rates of diagnostic imaging use by patient race and ethnicity in the setting of cancer staging, surveillance, or diagnosis in high risk or symptomatic (non-screening) populations. The included articles underwent data extraction including title, country of origin, publication year, number of participants, participant demographics, data source, clinical care setting, article conclusion, and whether patient health outcomes or strategies to promote health equity were evaluated.

Results

The search strategy returned 2908 non-duplicate papers of which 2510 were removed by title/abstract review and 385 by full text review leaving 13 meeting inclusion criteria. All 13 studies were conducted in the United States and included only adult patients. Thirty-eight percent of articles (5/13) were focused on cancer staging, 38% (5/13) on cancer surveillance, and 23% (3/13) on diagnosis of cancer in high-risk groups.

Thirty-eight percent of articles (5/13) used nationally represented data, 31% (4/13) of articles were single-institution, 23% (3/13) multi-institution or regional, and 8% (1/13) with state-level data. Ten articles (77%) found disparities in the use of imaging in some or all of the minority groups evaluated. Thirty-eight percent of articles (5/13) reported on patient health outcomes. None of the articles evaluated strategies to mitigate disparities in the use of imaging for cancer care.

Conclusions

Disparities exist in the use of radiologic imaging in the setting of adult cancer care. This may be a part of the causal pathway leading to the worsened outcomes observed in minority cancer patients. The existing body of literature is small and focused on adult patients. A minority of studies directly evaluated patient outcomes and none of the studies tested strategies to mitigate the observed disparities suggesting multiple avenues for future research.

Clinical Implications

Although there is existing literature on racial disparities in the use of diagnostic imaging for cancer care, there is a need to further evaluate this gap. Future research can broaden the populations studied, directly connect imaging disparities to health outcomes, and evaluate strategies to promote an equitable health care system.