Tackling cancer disparities

Research, outreach and care designed to eliminate barriers for minority groups

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Kekoa Taparra, MD, PhD, a Native Hawaiian, grew up watching so many family members die of cancer that he never imagined it was possible to be treated and recover from the disease. He has lost a dozen relatives to cancer, including two aunts, an uncle and a cousin who died from brain cancer when she was a toddler.

“I will never forget my aunt with breast cancer, who was so fatigued and unable to function that my mother literally had to carry her limp body from the bed to the bathroom,” said Taparra, a radiation oncology resident at Stanford Medicine and a Stanford Cancer Institute fellow. “Or my dad’s only sister, who died of endometrial cancer. I will never forget her screams — she was in so much pain. She died at home. I witnessed these things over and over.”

In recent years, Taparra has published more than a dozen studies on the cancer trends among Native Hawaiians and Pacific Islanders, sounding the alarm on the huge disparities in treatment between these indigenous groups and other patients with the disease.

He is among a growing number of advocates at Stanford Medicine seeking to equalize cancer treatment for members of marginalized groups, who are more likely to suffer from and die of the disease than their majority counterparts.

The Stanford Cancer Institute’s Office of Cancer Health Equity is spearheading the effort to help eliminate these disparities through partnerships with community organizations and other groups at Stanford Medicine.

Dinah Trevil, the office’s executive director, said underrepresented minorities experience higher cancer rates and deaths because of many factors, including missed and late diagnoses, limited access to cancer screenings, and reduced access to cancer care generally, especially high-quality care.

The center sponsors research in marginalized communities to better understand their needs and how they are impacted by cancer, with the goal of devising policies to improve equity in cancer treatment and prevention at the local and national level, she said.

Candice Thompson is medical director for the Office of Cancer Health Equity, overseeing programs to educate women about breast cancer, improve access to cancer care for underrepresented groups and expand their participation in cancer clinical trials.

Shaken by cancer deaths among Black women

Like Taparra, Candice Thompson, MD, has been deeply shaken by the cancer deaths in her community. When she was a medical student at Howard University, one mentor and one classmate — both young Black women like herself — were diagnosed with breast cancer. Her classmate died of the disease. The other was a professor, a breast surgeon, who died after a recurrence in her 40s.

While in residency at Georgetown University, another close friend who was only 25 was diagnosed with breast cancer. She survived after a difficult course of treatment.

“It was really scary,” said Thompson, a clinical assistant professor of surgery and member of the Stanford Cancer Institute. “I saw her go through a lot. She lost all her hair and had to freeze her eggs. Fortunately, it was found early and she’s cancer-free now.”

The experiences set the course for Thompson’s career as a surgeon specializing in breast cancer and as an advocate for more equitable cancer treatment for members of minority groups.

She is now the medical director for the Office of Cancer Health Equity, overseeing programs to educate women about breast cancer, improve access to cancer care for all underrepresented groups and expand their participation in cancer clinical trials.

For the past two years, Thompson has led an outreach program in Oakland to educate and empower Black women, who are at much greater risk of breast cancer than white women — particularly aggressive and hard-to-treat forms of the disease. In the United States, Black women with breast cancer are 40% more likely to die of the disease than white women, according to the American Cancer Society.

Thompson said biology could play a role, but there are other social and economic factors that account for the disparity. For instance, Black women might lack access to care, including early detection tools such as mammography, or they might delay seeking care out of fear or mistrust of the medical system, which has a history of bias against Black patients.

“If you are afraid to go to the doctor, you are not going to get the attention you need,” she said.

In a program supported by a Stanford Cancer Institute Clinical Innovation Fund grant, Thompson leads monthly seminars at community clinics and events at local churches to teach women about cancer prevention and treatment. She uses a model of a breast, created by professor of surgery Carla Pugh, MD, PhD, to show them how to do self-exams; talks about the role of early detection, genetics, nutrition and physical and mental health in the disease; and encourages women not to be afraid to participate in clinical trials. Several women have signed up for a clinical trial as a result of the program, she said.

Nationally, 10% of participants in cancer trials are from underrepresented groups; only 3% of participants in breast cancer trials are Black women. Some indigenous groups, such as Native Hawaiians and Pacific Islanders, aren’t represented at all in these trials.

“There’s a huge disparity,” Thompson said. “It means that we don’t know if there may be more adverse events in these groups once we roll out a particular treatment as a standard of care or if they may respond better to a different dose.”

Moreover, people who participate in clinical trials receive better treatment and are more likely to do well, said Manali Patel, MD, an associate professor of oncology and member of the Stanford Cancer Institute. She has studied racial disparities in cancer for decades and has been a mentor to Taparra in his equity work.

‘It’s discouraging that we are so many decades out from this being recommended as standard care. Twenty years later, we still see these vast disparities by race and income,’ said
Manali Patel, at left, with colleagues Erqi Pollom, center, and Kekoa Taparra.

Invisible Native Hawaiians and Pacific Islanders

After decades of advocacy, Native Hawaiians and Pacific Islanders continue to struggle for visibility on the cancer map, Taparra said, in part because many cancer researchers combine these communities with the larger Asian populations.

His analysis of outcomes for people with cancer in the United States, published in 2022 in JAMA Open Network, showed that when data for Native Hawaiians and Pacific Islanders are separated from Asian Americans, they actually have lower survival rates than Asian Americans and white people for nine of the most common cancers, including lymphoma as well as oral, endometrial, prostate and breast cancers.

In another study, published in 2023 in the Journal of the National Cancer Institute, Taparra and collaborators from the National Cancer Institute found that young Native Hawaiians and Pacific Islanders had some of the highest mortality rates from all forms of cancer among people with cancer ages 20 to 49 years old. It was the first time these indigenous groups were included in the national statistical studies, despite a federal mandate to do so, he said.

“Black people have always had among the highest rates in these reports. But this year, we found the young Pacific Islanders had the highest mortality,” Taparra said. “It really sparked a lot of interest and concern.”

There are many reasons for the disparity, including a historical mistrust of medicine, differing cultural perspectives and a dearth of clinicians who are representative of this population, said Erqi Pollom, MD, an associate professor of radiation oncology and member of the Stanford Cancer Institute. Clinicians also come and go on the islands, so there is little continuity of care for patients, Taparra said.

“Black people have always had among the highest rates in these reports. But this year, we found the young Pacific Islanders had the highest mortality. It really sparked a lot of interest and concern.”

Kekoa Taparra

But what is especially acute is the lack of access to facilities and adequate treatment for these island residents, Pollom said. Hawaii has only one accredited radiation oncology center, on Oahu, and patients from Hawaii’s other islands have to fly there to receive care.

One of Taparra’s uncles, for instance, died of metastatic prostate cancer and was in such terrible pain that he was unable to travel from his home on Maui to see a doctor, he said. Pollom said she has treated patients from Hawaii, particularly those who need multidisciplinary care for their tumors, but it is a great burden for them to get to Stanford Health Care, which has some high-level technologies, such as MRI-guided radiation and CyberKnife, that would otherwise be unavailable to them.

“I recently saw a patient who scraped together all her resources to fly to California,” said Pollom, who is vice chair of clinical operations for Stanford Medicine’s Radiation Oncology Department. “She was in tremendous pain during the flight and didn’t even have the resources to stay. So I think that weighs against patients in terms of access to those facilities that treat some of these complex cancers.”

Studies by her and Taparra have also shown that Native Hawaiians and Pacific Islanders are more likely to refuse radiation therapy or surgery, and that those who declined radiation were more likely to die. Taparra said the refusal to undergo radiation possibly harks back to the Cold War, when the United States detonated the equivalent of 7,200 Hiroshima bombs in the Pacific, which led to a spike in thyroid cancers in the region.

“It really echoes the historical trauma — the decimation of our population, and the lack of access to health care,” Taparra said. “I’m trying my best to amplify this message and the desire of our communities to be seen and known.”

Differences in care

Patel’s studies have shown that people from minority groups with cancer tend not to receive high-quality care and, when they do, mortality disparities tend to disappear.

“With every clinical advance we make, there is inadvertent worsening of disparities — and it’s largely due to the inability to get these treatments out to these communities to make sure they are equitably applied,” she said.

One example is genomic testing, which is often not offered to Black women and other underrepresented groups, she said. In genomic testing, doctors examine the genetic makeup of a patient’s tumor cells, a crucial step that can point toward the most effective treatment, Patel said.

“We have known for decades in breast cancer treatment that these tests are important so people know if they should receive chemo or not,” she said. For instance, the test might show that chemotherapy isn’t the most effective treatment for a patient — so the patient could avoid that therapy and its undesirable side effects.

“With every clinical advance we make, there is inadvertent worsening of disparities — and it’s largely due to the inability to get these treatments out to these communities to make sure they are equitably applied.”

Manali Patel, MD

To understand why patients who are members of minority groups don’t always receive tumor testing, Patel and her colleagues worked with five community groups in a state-funded project to survey and interview more than 800 low-income breast cancer patients from various racial and ethnic groups in Northern California. Most were Black women.

The researchers found many reasons for differences in care, including a lack of patients’ understanding of the test, a delay by clinicians in ordering it and gaps in care as patients switched providers. Cost was also an issue, as varying levels of insurance coverage sometimes led to out-of-pocket expenses for patients of as much as $1,000, Patel said.

The researchers are now working with a community advisory board to come up with policy changes to ensure that patients across the state have access to the test, she said.

“It’s discouraging that we are so many decades out from this being recommended as standard care,” Patel said. “Twenty years later, we still see these vast disparities by race and income.”

Colorectal surgeon Aaron Dawes, at left, with team members Eleanor Catherine Irvine Brown, clinical research coordinator, center, and Patricia Castañeda, community health worker. They focuses on educating Latinos about the importance of early screening for colon cancer, which is the second leading cause of cancer death in this group.

Gaps in care for Latinos

Colorectal surgeon Aaron Dawes, MD, PhD, has focused on another neglected group — Latinos with colorectal cancer, whom he often sees in his practice. Although the incidence of colon cancer among Latinos is not relatively high, the death rates are. Colon cancer is the second leading cause of cancer death in this group.

The reason: These patients often don’t receive proper treatment or get treatment too late to make a difference, according to his recent study in the Annals of Surgery.

“If the care this group is receiving is not up to par, it means we are talking about a plurality of Californians who are not getting good care,” said Dawes, an assistant professor of surgery and member of the Stanford Cancer Institute.

Dawes and his collaborators found that mortality rates among Latino patients started to decline when individuals received the recommended standard of care, including timely surgery to eliminate all cancer cells and the removal of the lymph nodes to stop the spread of the disease, he said.

“That means the main mechanism that drives the disparity is the disparity in treatment,” and the reasons behind that for Latinos may be different than they are for other underrepresented groups, he said.

He said there are few studies and little understanding within the medical field of cancer among Latinos, so he and his colleagues set out to fill the gap with a research project in California’s Central Valley, which has a large Latino population. The researchers partnered with several community groups, including the nonprofit Latino Cancer Institute, which supports Spanish-speaking community health workers, or promotoras.

In the project, funded by a Stanford Cancer Institute Equity Impact Research Seed Grant, the researchers conducted in-depth interviews with 21 people with rectal cancer and their caregivers. The community health workers advised the researchers on what questions to ask and provided translations when needed. Most of the patients had received care at Stanford Health Care at some point.

When asked what made it difficult to get treatment, many cited practical concerns such as finding transportation to go to regular radiation therapy appointments or the need to take time off from work and find babysitters for their children. But they also said language and cultural barriers made them ill at ease at times. Only 62 out of every 100,000 physicians in California speak Spanish.

“It all comes back to the community. The more we can understand the needs of a marginalized community — in this case the Latino population — the better we can fill the gaps in care and hopefully lead to better outcomes.”

Aaron Dawes, MD, PhD

“A lot of the concerns were centered on language and the trust between the team and the physician,” Dawes said. “They felt like their culture and beliefs weren’t incorporated into discussions about care, so there was a reticence to be engaged. And there were issues of health literacy — people who didn’t know about the risks of colon cancer.”

Even when interpreters were present, they might have spoken a Spanish dialect from another country and used terminology that the patients didn’t understand, the researchers found. He said some of the patients interviewed discussed cultural obstacles to care, including the concept of simpatia — not wanting to trouble doctors or burden family members, or a willingness to put a blind trust in the physician without any sense of personal empowerment.

Stigma around rectal cancer also discouraged some patients from being screened for the disease, so they were diagnosed at a later stage. Early diagnosis is important, Dawes noted, because if the disease is detected before it has spread to lymph nodes, patients don’t necessarily have to undergo chemotherapy. Early diagnosis means a better chance of survival.

Dawes said another obstacle to early diagnosis is that the majority of Latinos in Californian rely on Medi-Cal, the state program for low-income individuals, which does not fund colonoscopies as a first step. Instead, Medi-Cal uses a screening test that detects blood in the stool as a marker for the disease. But this test is not good at detecting polyps in the colon, which can be a precursor to cancer, Dawes said.

Patients also aren’t always offered the best quality care, he said. In some small community facilities, doctors might not keep up with current recommendations, so patients don’t receive the most up-to-date treatments, he said.

Dawes recently presented the study’s results at a meeting of the American Association for Cancer Research with colleagues Arden Morris, MD, the Robert L. and Mary Ellenburg Professor in Surgery II, and Sandra Zaky, MD, clinical associate professor of radiation oncology.

The researchers are seeking funding for a new project in which they pair each patient with a promotora who will guide them through diagnosis and treatment, while also providing social and mental health support, Dawes said.

“It all comes back to the community,” he said. “The more we can understand the needs of a marginalized community — in this case the Latino population — the better we can fill the gaps in care and hopefully lead to better outcomes.”

Trevil agreed. “We have to keep our pulse on the community and make sure they are involved in the conversations from the beginning, and that they are the source of the information, and they have some ownership in this work that we are doing,” she said.

But it will take a collective effort among communities, health care systems, academic centers and government organizations to bring about change to those long-standing inequities, she said. “It’s a chipping away. I can definitely see that progress is being made, but there is a lot of work to be done,” she said.

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Ruthann Richter

Ruthann Richter is a freelance science writer. Contact her at medmag@stanford.edu

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