WASHINGTON, United States (AFP) — People diagnosed with advanced colon cancer pay twice more per month for treatment in the United States than in Canada, but do not live any longer, researchers said Friday.

Canadian residents of British Columbia paid an average of US$6,195 per month, compared to patients in the northwestern US state of Washington who paid US$12,345, said the study released at the American Society of Clinical Oncology (ASCO) conference in Chicago.

The two regions are about 700 miles (1,100 kilometres) apart, have similar income levels, and a racial makeup that is mainly white with a significant Asian minority.

Canada has a single payer health system, while the United States has a mix of private insurance and government-funded health insurance.

“To our knowledge, this is the first study to directly compare treatment cost and use, along with health outcomes, in two similar populations treated in different health care models,” said lead author Todd Yezefski, a senior fellow at the Fred Hutchison Cancer Research Centre in Seattle, Washington.

The findings “may help us improve care and potentially lower health care costs,” he added.

The study tracked 1,622 patients with metastatic colorectal cancer in British Columbia and 575 in Washington State.

The median age of the patients in Canada was 66, while in the United States it was 60.

More patients in the US (79 per cent of those diagnosed) than in Canada (68 per cent) opted to undergo the most aggressive treatment available.

Both groups were treated with similar kinds of chemotherapy.

Despite paying about twice as much, US patients lived an average of 21.4 months after diagnosis. Canadian patients lived an average of 22.1 months.

Among those who decided not to pursue treatment, the average survival was 5.4 months in Washington and 6.3 months in British Columbia.

“As oncologists, we see the burden of high costs on patients and their families every day,” said ASCO chief medical officer Richard Schilsky.

“This study adds important context to the ongoing national conversation about rising treatment costs.”