Published in Science on July 3, 2024
By Vivian La
Nearly a quarter-century ago, the U.S. Centers for Disease Control and Prevention reported a troubling finding: Asian Americans had become the first racial minority for whom cancer is the leading cause of death. In 2000, nearly one in four, or 26% of the racial group, died from cancer compared with 23% for white, non-Hispanic Americans. But what this data for Asian Americans didn’t reflect was whether the dozens of subgroups within this broad population have a similar risk of death from the disease, and what factors underlie these differences.
Researchers leading the first national long-term cohort study on Asian Americans aim to shed light on these questions by tracking the health of tens of thousands of participants, who they say shouldn’t be viewed as a monolith.
“I think for too long, our communities weren’t at the table,” says epidemiologist Salma Shariff-Marco, a co-principal investigator of the study led by the University of California, San Francisco (UCSF) and funded with a $12.45 million grant from the National Cancer Institute.
First coined by civil rights activists in 1968 to counter racial stereotypes and give Asian groups a voice in policy, the aggregated term Asian American is a demographic definition used by federal agencies as well as health researchers. But lumping Asian Americans into one group creates a false sense of the burden of disease, Shariff-Marco and other researchers say.
For example, although cancer remains the leading cause of death for Asian Americans, the racial group has lower cancer rates overall and appears “healthier”. Yet more granular data show disparities within this group. For instance, Vietnamese American women have a high incidence of cervical cancer compared with Indian and Pakistani women. Among all Asian Americans, Korean Americans have the highest mortality rate for stomach cancer, but the lowest for prostate cancer. Shariff-Marco and others have quantified rising rates of breast cancer among Southeast Asians, but not Japanese Americans or Chinese Americans.
The tendency to lump Asian Americans together has meant less attention from the broader cancer research community and funding agencies. “There was this real disconnect between the fact that we see certain cancer burdens for certain communities, [and] the ability to get studies [funded] that are focused on our communities,” Shariff-Marco says.
The new study, called Asian American Prospective Research (ASPIRE), follows a trend of disaggregating Asian American health data. Most recently, a 2021 U.S. National Institutes of Health workshop recognized the need for more cohort studies in Asian American, Pacific Islander, and Native Hawaiian populations, which are often grouped together.
Starting in November, the UCSF team and partners plan to recruit 20,000 cancer-free participants between the ages of 40 and 75 across the country who will be followed for 5 years. The goal is 50,000 participants in the next 10 years if the team can find additional funding.
Participants will go to a community center or online and fill out surveys on lifestyle choices like diet and exercise to help researchers understand differences between ethnic groups that may contribute to cancer. Researchers will determine which cohort participants get diagnosed with cancer by linking study records to records of their patients in state cancer registries, insurance claims, and death records. By enrolling participants while they’re still healthy, researchers hope to better understand the factors that may lead to cancer in some and not in others.
Volunteers will also mail in saliva samples so researchers can examine biological markers such as chemical on-off switches called methyl groups that are attached to DNA. Some studies have suggested that stress-induced DNA methylation can shut off tumor suppressor genes.
Stress might stem from one’s physical environment or structural factors such as discrimination—all of which have been shown to contribute to cancer incidence, says epidemiologist Scarlett Lin Gomez, co-principal investigator of the UCSF study and director of the Greater Bay Area Cancer Registry. Stress is also associated with some established risk factors for cancer such as alcohol and tobacco use. The research team also wants to capture social and psychological stressors such as navigating the immigration process or experiencing structural racism.
“Given the recent climate of anti-Asian discrimination that we witnessed during the COVID pandemic, I think it’s important to look at these unique social, cultural experiences,” says David Zhu, a second-year medical student at Virginia Commonwealth University who researches Asian American health disparities and isn’t involved in the study. Stress has been studied at the cancer screening and treatment levels, but its role in causing cancer is less understood, Zhu says.
To recruit participants, UCSF researchers will collaborate with 20 academic institutions across the United States, dozens of community organizations like local churches, and health policy organizations focused on Asian Americans. For example, behavioral health scientist Grace Ma, director of the Center for Asian Health at Temple University, aims to recruit 7000 participants on the East Coast through her center’s existing network of Asian American–specific community organizations and political groups.
Ma’s team, which will accommodate different technology needs or languages, says it might be challenging to communicate the long-term importance to participants, given they won’t see any direct benefits. The plan, Ma says, is to continuously report findings back to the community to build trust. The data will also be available to other researchers for further study.
The findings could lead to prevention strategies for specific groups, says Edward Christopher Dee, a radiation oncology resident at the Memorial Sloan Ketterling Cancer Center who isn’t involved in the study. “Such work could lead to increased awareness amongst Asian Americans themselves regarding their own cancer risk,” Dee says.
Awareness is paramount because cancer doesn’t discriminate, Shariff-Marco says. “I’m just so excited to get this off the ground and get this to our communities,” she says. “That’s going to put us in a position to start answering research questions that up until now, we just haven’t been able to do.”
Vivian La 