White and Asian American patients found to be overrepresented in cancer trials, study says

Precision oncology – developing and guiding cancer treatment based on the molecular makeup of tumors – is changing cancer care. Personalized treatment can provide better results than one-size-fits-all solutions, scientists hope.

But according to a new study, the clinical trials behind these new developments aren’t using a representative group of patients.

When a group of Boston-area researchers analyzed studies in the government registry for clinical trials, they found white and Asian American patients were overrepresented for certain cancers.

The study, published in JAMA Network Open, looked at demographic data for nearly 6,000 enrollees of 93 precision oncology clinical trials. Researchers homed in on breast, prostate, lung and colorectal cancer studies in the database, which makes the registration and results of government-funded trials public.

If the trials studied were representative, their balance of participants from different races and ethnicities would have reflected the proportion of Americans with those cancers.

Instead, there was a disproportionate number of participants of white and Asian ancestry in all those studied, and Black and Hispanic patients were understudied. The number of white participants was 35% higher than the expected proportion of patients, and the number of Asian American participants was 46% higher across the board. Twenty-four percent fewer Hispanic and 49% fewer Black patients participated in the trials than would be representative.

The disparities were even higher when it came to different cancers. Black patients were underrepresented by 69% for lung cancer, and Asian American patients were overrepresented by 196%.

Nationwide, cancer death rates are higher for Black patients than other groups. Cancer occurs in Black males 9% more often than white males, yet 22% more Black males with cancer die than their white male counterparts.

Mistrust and barriers to care could explain the numbers, the researchers say; reaching proportional enrollment in precision oncology studies will involve education for both potential participants and bias training for researchers.

“Overall,” they write, “our findings highlight the need to increase enrollment of these groups into future clinical studies. All individuals deserve to benefit from cancer research breakthroughs.”