Blood cancer survival rates in Canada on the rise, report finds
Overall cancer survival rates have improved to 63%, Canadian Cancer Society says
There was a time David Mitchell didn't believe he would survive until his 50th birthday.
But he reached that milestone earlier this year, thanks to a life-saving stem cell transplant to treat non-Hodgkin lymphoma.
"They basically said, 'Yup, there is zero sign of cancer anywhere,"' the Ottawa resident recalls of a checkup that followed previous failed rounds of chemotherapy and radiation. "It was astounding."
The Canadian Cancer Society says Mitchell can count himself among the growing number of people who are surviving blood cancer due to precision medicine — treatments based on a person's genes or other unique features of the person's cancer.
New statistics released Wednesday suggest the survival rate for blood cancers is outpacing the survival rate of any other cancer.
Overall cancer survival rates have improved to 63 per cent — up eight percentage points since the early 1990s. But the most gains have been among common blood cancers, including non-Hodgkin lymphoma, multiple myeloma and leukemia, with their survival rate increasing 16 to 19 percentage points.
Leah Smith, a spokesperson for the society, says that's largely due to advancements in precision medicine.
"Certain new drugs that have come on the market have really been game-changers for blood-related cancer."
Smith say this is the first year in several years the organization has had updated data on cancer survival rates.
An estimated 21,000 Canadians are expected to be diagnosed with blood cancer in 2019, representing about 10 per cent of all cancer diagnoses that year.
"Across the board, we're seeing improvements in survival with almost all of the cancers that we studied," Smith says, adding that no survival rates dropped among the 23 cancers studied.
Dr. Gerald Batist is director of the Segal Cancer Centre at the Jewish General Hospital in Montreal. Batist, who was not involved in the cancer society's report, said he's optimistic about how survival rates, particularly for blood cancers, are heading in the right direction.
"I would say that the rate of these improvements is picking up speed."
The report compared data gathered from 1992 to 1994 with information from 2012 to 2014.
Mitchell's cancer was already advanced by the time he was diagnosed May 15, 2015. Tumours were found buried in his abdomen, groin, spine and neck, with a grapefruit-sized mass on his spleen.
Chemotherapy and radiation failed, and doctors told him he had three weeks to live, Mitchell recalls. He was told his best shot was to find a donor who could provide healthy stem cells from their bone marrow to replace his damaged cells — but finding a match would take months.
So doctors bought time in July 2016 with an autologous transplant instead, which used stem cells from Mitchell's own body. Mitchell says that kept him alive until September 2016, when he got a match through an international donor program.
A year later, he was given the momentous news.
"At that point I was so conditioned to have bad news that I was expecting bad news and to get news like that, it's probably the best feeling I've ever had in my life," he says.
Breast cancer deaths decline
In other findings, the society's 2019 report also notes female breast cancer death rates have decreased by an estimated 48 per cent since they peaked in 1986, thanks to improvements in early detection and treatment. That's an improvement from the society's 2017 report, which had estimated death rates would drop by 44 per cent, says Smith.
However, pancreatic cancer is now on track to become the third leading cause of cancer death in Canada in 2019, overtaking breast cancer.
"Pancreatic cancer isn't a cancer that's talked about a lot for a couple of reasons — it's only the 12th most commonly diagnosed cancer but it has one of the lowest survival rates of any cancer," says Smith.
"It's becoming an increasingly large contributor to the overall cancer burden. From a relative perspective, we're seeing it's inching its way up."
The five-year survival rate for pancreatic cancer is about eight per cent, a slight improvement from five per cent in the early 1990s, but Smith says that more work clearly needs to be done.
'New habit, new product'
Colorectal cancer is the second leading cause of cancer death, while lung cancer continues to be the leading cause of cancer deaths by far in Canada, accounting for more than colorectal, breast and prostate cancer deaths combined.
Smith notes that lung cancer rates have declined over the last several decades, but primarily among males. The society's 2019 study is the first to detect a decline in lung cancer and lung cancer death rates among females — likely due to smoking prevention, cessation and education programs, she says.
"It's really a reflection of past smoking patterns," says Smith. "Males started smoking earlier and then they quit smoking earlier."
Smith says it's not clear what an apparent prevalence of vaping among children will do for these rates, but there is concern that numbers could backtrack, especially if social acceptance of vaping encourages the renormalization of smoking.
"We don't know the health effects of vaping at this stage, it's still a relatively new habit, new product," she says.
The data was collected in conjunction with the Public Health Agency of Canada and Statistics Canada.
Nearly one in two Canadians will be diagnosed with cancer in a lifetime.
This year, an estimated 7,450 people in Canada are expected to die of a blood cancer. Mitchell considers himself to be among the fortunate.
"I didn't actually think I was going to see my 50th, but here I am," he marvels.
With files from CBC's Christine Birak