Landmark study provides first national look at Métis cancer incidence and survival

When researcher Loraine Marrett became aware in the late 1980s that there was little-to-no information on cancer in Canada's Indigenous people, she resolved to take action.

“For a long time, I've been interested in looking at cancer trends and patterns in different groups of people,” says Marrett, who currently serves as senior scientist emeritus at Cancer Care Ontario.

“When I realized that we lacked this type of research, my first question was, how can we change this?”

In the years that followed, Marrett and others found a way to track cancer in the large population of First Nations people in Ontario and later in other provinces. However, identifying sources of reliable health data about Métis populations proved a more intractable problem.

That key information is finally available, thanks to improved data collection and reporting methods in Canada. And it is now helping to inform the research Marrett envisioned all those years ago.

One example is a landmark study recently published by the Canadian Medical Association Journal. The study, led by Marrett and other researchers from Cancer Care Ontario and the Métis National Council, is the first to quantify cancer incidence and survival among Métis people across Canada.

The analyses found that Métis men and women in Canada are diagnosed with lung, liver, larynx and gallbladder cancers at significantly higher rates than non-Aboriginal adults. In addition, Métis women are diagnosed at higher rates for breast and cervical cancers than non-Aboriginal women.

Some key findings from this study suggest that lifestyle changes and behaviours might reduce the high rates of cancer incidence in Métis people.

For example, the study found high incidence of lung, breast and liver cancers among Métis people; these cancers are all associated with risk factors such as obesity and smoking tobacco. As well, higher incidence of cervical cancer suggests that more Métis women need to get regular screening to detect changes in the cells of the cervix before they develop into cancer.

Advances in data collection

In the past, it had been a challenge to conduct studies like this as there had been very limited data available about cancer in Métis (or First Nations and Inuit) people in Canada.

This is largely because health data systems in Canada don't typically include any data about race or ethnicity - although some of the territories do record First Nations, Métis or Inuit status. Gathering such data requires special studies that use other sources of race/ethnicity information to augment cancer registry and other health data.

Recently, Statistics Canada linked Canadian census data to health databases, allowing researchers to track cancer and death rates among people who self-identify as Métis in the census.

“The idea of studying cancer in this group of people has been near and dear to my heart for a long time,” says Marrett. “When this data became available, it seemed like a golden opportunity to uncover the impact that cancer has on Métis people in Canada."

New data sources have made other work possible in recent years. For example, Marrett completed a report in partnership with the Métis Nation of Ontario that looked at lifestyle factors, such as tobacco smoking, alcohol consumption and other behaviours that put Métis people in Ontario at higher risk of getting cancer than non-Aboriginal Canadians.

As the first study to take a national look at the issue of cancer in Métis people, Marrett’s work underlines the importance of having access to this information. The data can help pinpoint communities most affected by cancer, and help the system leverage relevant health services for them. 

“Now that we have access to this data, we will be able to conduct more studies like this in the future. [We can] recommend actions to improve the health of these populations and continue to track this issue over time,” says Marrett.

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