Cancer Trends and Screening in First Nations Patients

First Nations patients in Canada appear to be diagnosed with certain cancers at younger ages and later stages than other Canadians, which could indicate a need for better screening programs, according to new data presented at conferences in the United States and Canada.

In Ontario, Canada, for instance, First Nations patients are diagnosed with cervical, colon, and lung cancers at a younger age and colon and lung cancers at a later stage. Breast cancer diagnoses occur at similar ages and stages as in the general non-Indigenous population.

“These findings have generated more investigation to try to understand why these trends are happening and the root causes to help fix them,” researcher Jill Tinmouth, MD, a scientist and staff gastroenterologist at Sunnybrook Health Sciences Centre in Toronto, Ontario, told Medscape Medical News. “I suspect this is driven by the social determinants of health, as well as connections to processed foods, tobacco use, antibiotic exposure, obesity, and other factors.”

The data were presented in May at the Canadian Centre for Applied Research in Cancer Control conference in Ontario, as well as at Digestive Disease Week in Washington, DC. The research will be published in medical journals this fall.

Community-Driven Research

First Nations community members from the Joint Ontario Indigenous Health Committee expressed concerns to Ontario Health’s Indigenous Cancer Care Unit about being diagnosed with cancer during the province’s four main screening programs — for breast, cervical, colon, and lung cancers — before screening age eligibility. Data also suggested lower screening program participation among First Nations people.

With Indigenous partner support, Tinmouth and colleagues linked health administrative datasets at ICES and Ontario Health to analyze screening program data for First Nations patients and the general population. The research team looked at patients aged 18-85 years who participated in the screening programs from 2000 to 2018 and calculated hazard ratios (HRs) for ages and stages at cancer diagnosis.

Overall, First Nations patients were more likely to be diagnosed at a younger age with cervical (HR, 1.44), colorectal (HR, 1.42), and lung (HR, 1.38) cancers but not breast cancer.

Similarly, First Nations patients were more likely to be diagnosed with late-stage colorectal (HR, 1.53), lung (HR, 1.46), and cervical (HR, 1.43) cancers but not breast cancer.

These findings could indicate different trends, Tinmouth noted. Diagnosis at a younger age but not later stage could mean that cancer was found earlier in the lifespan, but patient outcomes may be similar.

However, finding cancer at a younger age and later stage could spell “double trouble,” she said, which indicates the colorectal and lung screening programs should be inspected further. A closer look at the cervical cancer screening program revealed that although the age at diagnosis was earlier, it was still within the current age eligibility guidelines.

In addition, the risk for being diagnosed with cancer during screening programs was small for First Nations patients compared with the risk of dying from other causes, which could be a positive indicator — or at least reduce some concerns about screening program gaps.

“The key principle here is doing community-driven work that is led by community concerns,” said Tinmouth. “Further efforts should be made to address cancer screening barriers and improve cultural safety in the healthcare system.”

Improving Screening Programs

Tinmouth and colleagues are sharing their findings with community partners, such as the Joint Ontario Indigenous Health Committee and First Nations leaders, and health system stakeholders, such as screening program leaders, to develop design changes for the colorectal and lung cancer screening programs. As part of an ongoing Catching Cancers Early grant, they also plan to analyze First Nations participation in cancer screening and follow-up.

Data from other provinces indicate additional trends for further investigation and improvement. In Alberta, Canada, for instance, breast cancer incidence rates appear to be increasing, and the cancer often is diagnosed at later stages for First Nations women. Screening program participation rates were about 24% lower for First Nations women, who were more likely to be diagnosed with stage II cancer. In addition, after diagnostic tests, it took about 2-4 weeks longer for First Nations women to receive their first diagnosis, as well as their definitive diagnoses of cancer.

“Collectively, these findings suggest that access to and provision of screening services for First Nations women may not be equitable and may contribute to higher breast cancer incidence and mortality rates,” said Karen Kopciuk, PhD, an adjunct professor of medicine in oncology and community health sciences at the University of Calgary, Calgary, Alberta, and research scientist with Cancer Care Alberta. Kopciuk and colleagues published their findings in Cancer Control earlier this year.

“Collaborations between First Nations groups and screening programs are needed to eliminate these inequities to prevent more cancers in First Nations women,” she added.

More broadly, cancer incidence and mortality are increasing across numerous Indigenous groups in Canada — including First Nations, Inuit, and Métis — compared with non-Indigenous Canadians, according to research by oncologists in Ottawa and Montreal. In addition, Indigenous people face higher risks for cancers associated with known modifiable risk factors, including breast, cervical, colorectal, lung, ovary, prostate, and some hematologic malignancies, which could point to major areas for intervention.

“Collaborative initiatives under Indigenous leadership have drawn attention to specific issues such as screening, funding, and culturally appropriate care and have identified resources necessary to address these problems,” said Matthew Beckett, MD, a radiation oncologist at the University of Ottawa, Ottawa, Ontario. He and his colleagues published their findings in the Journal of Cancer Policy.

“Jurisdictional and administrative challenges have hindered high-quality cancer care for Indigenous peoples since the country’s inception,” he said. He spoke in favor of “critical analysis of the existing cancer systems” and restructuring under new leadership with multidisciplinary collaboration.

The Ontario study was funded by the Canadian Institutes of Health Research and supported by ICES, which is funded by an annual grant from the Ontario Ministry of Health and the Ministry of Long-Term Care. The Alberta study was funded by an operating grant from the Canadian Institutes of Health Research. The Ottawa study received no funding. Tinmouth, Kopciuk, and Beckett reported no relevant financial relationships.

Carolyn Crist is a health and medical journalist who reports on the latest studies for Medscape Medical News, MDedge, and WebMD.