Poorer Canadians less likely to survive cancer: study

A new study suggests cancer patients from poor neighbourhoods are less likely to survive than their wealthier counterparts.
Cancer patients from poor communities have lower survival rates than
those from more affluent neighbourhoods, a new Canadian study has found.


What's more, the research team discovered that the explanation for
similar disparities in U.S. research -- that patients from poorer areas
are more likely to be diagnosed when their cancer is at a later stage --
did not hold true.

The researchers, led by Dr. Christopher Booth at the Cancer Research
Institute at Queen's University in Ontario, found that poorer patients
had a greater chance of dying prematurely from their disease even though
cancer stage at the time of diagnosis was similar across socioeconomic
groups.

"Contrary to what has been reported in studies from the U.S., we have
found that stage of cancer at time of diagnosis does not account for
any substantial component of the difference in survival across social
groups," Booth said in a statement.

The findings, though only gleaned from Ontario data, suggest other
factors play a role in survival, including the unique biology of each
patient's disease, the presence of other illnesses, access to treatment
and overall quality of care.

The study was published Monday in Cancer, the journal of the American Cancer Society.

For the study, the research team compared median household income
data from the 2001 Canadian census with diagnosis information from the
Ontario Cancer Registry. The team analyzed all cases of breast, colon,
rectal, non-small cell lung, cervical and laryngeal cancer diagnosed in
the province between 2003 and 2007.

Their findings include:

• The chance a woman from a poor community will be alive five years
  after a breast cancer diagnosis is 77 per cent, compared to 84 per cent
  for a wealthy woman.
  
• Fifty-two per cent of patients with colorectal cancer from poor
  neighbourhoods are still alive five years after diagnosis, compared to
  60 per cent of patients from wealthy communities.
  

The team said the fact that stage of disease at the time of diagnosis
was similar across socioeconomic groups may be explained by universal
health coverage in Ontario, "which may facilitate access to primary care
physicians and/or cancer screening," Booth said.

However, the disparity in survival rates, while they seem small, "are
important and meaningful differences," he told The Canadian Press.

"If we had a form of chemotherapy or cancer treatment that led to an
improvement or difference in five-year survival of seven, eight, nine
per cent -- the order of magnitude we're seeing with these differences
-- it would be a blockbuster home run as far as cancer treatment
advances," Booth said.

The team said further research is needed to identify the specific
factors that are leading to the disparities in survival, which will then
allow experts to devise strategies to reduce those disparities.