AACR Cancer Disparities Progress Report 2024: Achieving the Bold Vision of Health Equity

Remarkable progress made against cancer in the United States is reflected by a 33% decline in the overall cancer mortality rate between 1991 and 2020 (1). Despite this reduction, 2,001,140 new cases of and 611,720 deaths from cancer are projected in 2024 in the United States (1). Furthermore, the burden of cancer is higher among certain segments of the US population that include racial and ethnic minority groups, individuals living in rural areas, those under persistent poverty, and those belonging to the sexual and gender minority (SGM) communities (2). It is encouraging that disparities for some cancer types are narrowing. For example, mortality from lung cancer among non-Hispanic Black men has significantly reduced in the past two decades when compared with non-Hispanic White men (3). Despite narrowing trends, cancer disparities remain a serious challenge to public health and a significant barrier to achieving health equity.

Black and Indigenous individuals have the highest overall cancer death rates of all US racial or ethnic groups (2). Black men are twice more likely to die from prostate cancer compared with White men (3). Black women are 40% more likely to die from breast cancer compared with White women (3). Black individuals are twice as likely to be diagnosed with and die from multiple myeloma (3). Compared to White people, incidence rates for cervical cancers are higher among American Indian, Alaska Native, and Hispanic women (2). Lung cancer incidence is rising among Asian women, especially in those who are younger and have never smoked (4).

Similarly, individuals who live in rural counties are 38% more likely to be diagnosed and die from lung cancer compared with those who lived in urban, metropolitan areas (2). Individuals who identify as transgender are at a 76% higher risk of being diagnosed with advanced-stage lung cancer compared with cisgender individuals (5). Breast cancer risk is higher among SGM women compared with heterosexual women. Transgender women have a 60% lower risk of developing prostate cancer compared with cisgender men but are twice as likely to die from it (6). Research has identified multiple interconnected drivers of health that contribute to well-being and health outcomes of people (Fig. 1).

Cancer disparities are in part driven by differences in biological factors that stem from ancestral variations between populations. For instance, somatic mutations of the EGFR gene are commonly observed in patients with lung cancer. The frequency of EGFR mutations follows patterns resulting from the human diaspora out of Africa as well as more recent migration (forced or otherwise) of population groups to new geographic locations (Fig. 2; ref. 7). Understanding differences in the genome, epigenome, transcriptome, microbiome, and immune system can help researchers and clinicians better tailor treatment plans with the use of personalized medicines. Unfortunately, the majority of available data on cancer etiology are based on studies of individuals with European ancestry (8). As highlighted in the report, various institutions, organizations, and government entities are encouragingly taking steps to increase the diversity of study populations and tumor databases. Another major challenge is that currently available cancer models, such as cell lines, animal models, and patient-derived xenografts, lack inclusion of racial and ethnic minority groups (8, 9).

Modifiable risk factors, such as tobacco use, physical inactivity, UV exposure, alcohol consumption, pathogenic infections, poor diet, and obesity, contribute to 40% of all new cancer cases. Long-standing inequities in drivers of health (Fig. 1) contribute to significant disparities in the prevalence of risk factors among socially, economically, and geographically disadvantaged populations. Studies show that exposure to or lived experiences with racism, micro-aggressive behavior, and stress leads to increased levels of alcohol consumption and smoking (10). Built environments determine exposures to sunlight, chemical pollutants, social interactions, ability to exercise in physically safe environments, and/or stress, which can impact health (11–13). Disadvantaged populations frequently experience higher levels of exposure to pollutants such as radon as well as occupational exposure to chemical pollutants such as pesticides, which can increase the development of cancers (14–16).

Screening for precancerous or early-stage cancers can help intercept cancers when they are easier to treat. Medically underserved communities experience substantial disparities in receiving the recommended cancer screening and follow-up care if a screening test shows an abnormality. In 2021, in the United States, only 52.8% of American Indian and Alaska Native and 66.6% of Asian women were up to date with breast cancer screening compared with 75.7% of non-Hispanic White women (17). Only about 64% of eligible Asian, American Indian, and Alaska Native individuals were up to date with the recommended cervical cancer screening compared with 78% of White individuals (17). Furthermore, those living 138% below the federal poverty level, as well as those with less than a high school education, were less likely to be up to date with colorectal cancer screening (18). Mistrust of medical providers, lack of knowledge about screening, and barriers to follow-up care also contribute to screening disparities. Utilization of culturally tailored, evidence-based information, education, and screening resources delivered through community health educators can help to increase participation in screening programs among racially and ethnically diverse communities and in rural areas (19, 20).

Developing novel cancer treatments rely on clinical trials, which establish whether a new treatment is safe and efficacious. Patients from racial and ethnic minority groups and medically underserved populations experience multilevel barriers to participating in cancer clinical trials. Some of these barriers operate at an individual level for patients as well as health care providers but many operate at the systemic or institutional levels (21). For example, of the pivotal clinical trials that supported the approval of 82 novel anticancer therapeutics by the FDA between 2015 and 2021, 90% and 73% lacked adequate representation of Black and Hispanic/Latino patients, respectively (21). Despite remarkable advances in surgery, radiotherapy, chemotherapy, molecularly targeted therapy, and immunotherapy, medically underserved populations experience more frequent and higher severity of multilevel barriers to quality cancer treatment. These include treatment delays, lack of access to guideline-adherent treatment, undertreatment, refusal or early termination of treatment, treatment receipt at low-volume hospitals and community settings rather than comprehensive cancer centers, and higher rates of treatment-related and/or financial toxicities (22, 23). Patients from disadvantaged population groups may also experience overt discrimination and/or implicit bias during the receipt of care (24). Community outreach and engagement efforts and patient navigation programs that build trust and improve communication with historically underserved patients and provide financial, housing, food, transportation, language, health literacy, social, and clinical support can increase participation of minoritized groups in clinical trials and reduce disparities in cancer treatment (25). Research shows that racial and ethnic disparities in cancer outcomes can be eliminated if every patient has equitable access to guideline-adherent care (26).

In 2022, there were 18.1 million cancer survivors in the United States (27). The number of cancer survivors who belong to racially and ethnically minoritized groups is projected to grow over the coming decades. Survivors who belong to medically underserved populations are at an elevated risk of worse health-related quality of life, which has been shown to increase the likelihood of cancer recurrence and mortality (27, 28). Without more equitable cancer control efforts, disparities in survivorship will widen, potentially increasing the future cancer burden. In this regard, one of the evidence-based strategies discussed in the report is the use of community-based, tailored solutions that meet the specific needs of every patient and include patient advocates and patient navigators as key partners. Such approaches can help address the specific social, psychological, medical, and physical needs of the patient, increase the quality of life, bolster adherence to follow-up care, and identify financial concerns, thus providing equitable health care and reducing the overall cost of cancer care (29).

A diverse cancer research and patient care workforce is vital to achieving health equity. The underrepresentation of minority populations in cancer science and medicine remains a significant concern and may contribute to cancer disparities. People from minority groups often face systemic barriers to attaining leadership positions in health care. According to a recent survey, among 82 cancer centers, including 64 NCI–designated and 18 emerging centers, 79% of director positions were held by non-Hispanic White individuals (30). This underrepresentation of racial and ethnic minority individuals may result in a lack of diverse perspectives when major decisions are made about cancer research priorities and resource allocation. The Center to Reduce Cancer Health Disparities at the NCI plays a pivotal role in enhancing workforce diversity by leading the NCI's efforts to train students and investigators from diverse backgrounds, thereby fostering a pathway that can elevate diverse voices into leadership roles in cancer research.

The AACR Cancer Disparities Progress Report 2024 ends with a call to action urging policy makers and other stakeholders committed to eliminating cancer disparities to provide robust, sustained, and predictable funding increases for US federal agencies and programs tasked with reducing cancer disparities; support data collection initiatives; prioritize cancer control initiatives and increase appropriate screening for early detection and prevention; increase the diversity of the cancer care workforce; and enact comprehensive legislation to eliminate health inequities

No disclosures were reported.