Black and Hispanic patients continue to be notably underrepresented in clinical cancer research, although research noted that participation is on the rise.
Despite Black and Hispanic patients continuing to be underrepresented in clinical cancer trials, minority participation has increased for diseases such as breast cancer, colorectal cancer, lung cancer, and prostate cancer, according to a study published in Cancer.
For Black patients, the odds of participation increased between 2015 to 2019 in clinical trials for breast cancer (OR, 2.19; 95% CI, 2.07-2.32; P <.001), lung cancer (OR, 1.54; 95% CI, 1.38-1.73; P <.001), and prostate cancer (OR, 1.14; 95% CI, 1.04-1.26; P <.001). Hispanic patients had increased odds of participation in clinical trials for breast cancer (OR, 3.32; 95% CI, 3.09-3.56; P <.001), colorectal cancer (OR, 2.46; 95% CI, 2.04-2.96; P <.001), lung cancer (OR, 3.88; 95% CI, 3.20-4.69; P <.001), and prostate cancer (OR, 1.70; 95% CI, 1.42-2.04; P = .005).
A total of 242,720 patients were included in the final cohort with 197,320 non-Hispanic White, 21,190 Black, 11,587 Hispanic, 6880 Asian/Pacific Islander, and 839 American Indian/Alaskan Native patients; 3094 patients were of another race. The median age for breast cancer patients was 56 years, 60 years for colorectal, 65 years for lung, and 68 years for prostate. Within the population, 71.7% of patients were female.
When examining trial participation from 2015 to 2019 vs the proportion of incidence from 2015 to 2017, Black (OR, 1.75; 95% CI, 1.67-1.83; P <.001) and Hispanic (OR, 1.19; 95% CI, 1.12-1.25; P <.001) patients were more likely to participate in breast cancer clinical trials vs non-Hispanic White patients. Additionally, Black (OR, 0.58; 95% CI, 0.50-0.67; P <.001) and Hispanic (OR, 0.74; 95% CI, 0.64-0.87; P <.001) patients were underrepresented in clinical colorectal research, as well as being underrepresented in lung cancer clinical research (Black: OR, 0.83; 95% CI, 0.76-0.91; P <.001; Hispanic: OR, 0.66; 95% CI, 0.57-0.77; P <.001). Investigators also noted that Black (OR, 0.58; 95% CI, 0.51-0.66; P <.001) and Hispanic (OR, 0.85; 95% CI, 0.79-0.92; P <.001) patients with prostate cancer were underrepresented in clinical research.
When the authors compared clinical trial participation among elderly and nonelderly patients from 2015 to 2019 with breast cancer incidence from 2015 to 2017, investigators identified that patients older than 65 years were underrepresented (OR, 0.27; 95% CI, 0.27-0.28; P <.001). Additional findings indicated that patients with colorectal cancer who were older than 65 years were underrepresented (OR, 0.36; 95% CI, 0.33-0.39; P <.001) in clinical research, and those with lung cancer older than 65 years were less likely to participate (OR, 0.59; 95% CI, 0.56-0.62; P <.001). Women also appeared to be underrepresented in cancer research when comparing participation from 2015 to 2019 with the proportion of cancer incidence among male and female patients from 2015 to 2017 for colorectal cancer (OR, 0.73; 95% CI, 0.67-0.79; P <.001) and lung cancer (OR, 0.89; 95% CI, 0.83-0.93; P <.001).
Investigators did not observe any change with regard to participation in colorectal cancer clinical trials among Black patients (OR, 1.15; 95% CI, 0.97-1.36; P = .096), although an increase was observed among Asian/Pacific Islander patients (OR, 2.48; 95% CI, 2.00-3.08; P <.001). Lung cancer clinical trials also saw an increase in participation from Hispanic patients (OR, 2.21; 95% CI, 1.80-2.71; P <.001), and Asian/Pacific Islander patients (OR, 3.88; 95% CI, 3.2-4.69; P<.001).
An increase was seen in lung cancer trial participation among elderly patients (OR, 1.38; 95% CI, 1.29-1.47; P <.001) and female patients (OR, 1.17; 95% CI, 1.10-1.24; P <.001) was also observed. In terms of prostate cancer clinical trials, an increase in participation was also observed among Asian/Pacific Islander patients (OR, 1.64; 95% CI, 1.27-2.11; P <.001). In recent years, elderly participation has also increased (OR, 1.15; 95% CI, 1.07-1.24; P <.001).
Javier-DesLoges J, Nelson TJ, Murphy JD, et al. Disparities and trends in the participation of minorities, women, and the elderly in breast, colorectal, lung, and prostate cancer clinical trials. Cancer. Published Online November 22, 2021. doi:10.1002/cncr.33991