Underrepresentation of Hispanics in clinical trials for liver cancer in the United States over the past 20 years

Importance: Accurate representation of racial and ethnic population subgroups in clinical trials is fundamental to ensure universal effectiveness of new therapies as well as to decrease disparities in oncology care.

Objective: To determine whether Hispanic people are underrepresented in Phase I and II clinical trials for liver cancer in the United States.

Participants: A database search was performed in clinicaltrials.gov for interventional liver cancer studies based only in the US with reported results from September 1, 2002, to February 1, 2023. A total of 37 trials with 963 total patients met inclusion criteria and were included for further analysis. Proportion of total patients by race/ethnicity was calculated for non-Hispanic white, non-Hispanic black, Asian, Hispanic, and American Indian/Alaska Native subpopulations. The age-adjusted incidence rates of liver and intrahepatic bile duct were acquired from the National Cancer Institute, Surveillance, Epidemiology, and End Results Program.

Results: Liver cancer incidence rates (per 100,000 people) were highest in Indians/Alaska Native people (18.8 cases) followed by Hispanic people (15.1 cases), then Asian people (12.5 cases), then non-Hispanic black people (11 cases), and non-Hispanic white people (7.5 cases). From a total of 91 phase I or II clinical trials for liver cancer in the US, 41% reported race/ethnicity enrollment data; among these, 62.8% of patients were non-Hispanic White, 15.9% were non-Hispanic black, 8.8% were Hispanic, 12.7% Asian, and 0.5% American Indian/Alaska Native.

Conclusions and relevance: Less than half of phase I or II clinical trials for liver cancer in the US in the last 20 years reported race/ethnicity data to clinicaltrials.gov. Compared to the relative incidence rate of liver cancer, non-Hispanic black people and Hispanic people are underrepresented in these clinical trials.