Nearly half of Canadians to develop cancer in their lifetimes: Cancer Society

CTV National News: Cancer rates rising? Scientists announced today that they now estimate half of all Canadians will be diagnosed with cancer. Avis Favaro reports.

Nearly half of all Canadians are expected to be diagnosed with some form of cancer in their lifetime, according to new numbers from the Canadian Cancer Society.

For men, the lifetime risk of developing cancer is 49 per cent; for women, it’s 45 per cent, according to Canadian Cancer Statistics annual report for 2017.

That’s a big jump from the 2016 report, which found that only two out of five Canadians could be expected to develop cancer in their lifetimes (45 per cent of men and 42 per cent of women).

But the Cancer Society says this year’s report, compiled with the Public Health Agency of Canada and Statistics Canada, uses a new approach to calculate lifetime risk that better captures cancers that might have occurred in the past.

"The new numbers are a better reflection of the risk of being diagnosed with cancer at some point in life, whether in the future or in the past," the group said, noting their new methodology is similar to that being used in the United States and United Kingdom.

Dr. Leah Smith, one of the report’s authors and an epidemiologist with the Cancer Society, says the numbers appear striking.

“I think they’re a bit of a reality check about the challenges we continue to face with cancer,” she told CTV’s Your Morning Tuesday.

But, she adds, there are a few important points to keep in mind.

“First, cancer is very much a disease of aging. We are living longer than we used to, so that’s part of the reason this number is so high,” she said.

Cancer is a disease that mostly affects those aged 50 and older, and the risk simply increases with age, the society says.

Of the estimated 206,200 Canadians who will be diagnosed with cancer this year, almost 90 per cent will be older than 50. More specifically, about 45 per cent of all cancers this year will be in people aged 70 and older. So as more Canadians live into old age, the number of cases is bound to continue to rise.

“Another thing to consider is that more and more people are surviving their cancer diagnosis,” Smith added. “We’re getting better at fighting this disease, and so the diagnosis isn’t as scary all the time as it perhaps used to be in the past.”

The overall cancer survival rate has increased from about 25 per cent in the 1940s to 60 per cent today, thanks to cancer prevention programs, improved early detection and better treatment.

The top four most-diagnosed forms of cancer are lung cancer, breast, colorectal and prostate cancer.

“Those have been the top four leading causes of cancer for quite some time,” Smith said.

The good news is that many cancers can be prevented. In fact, it’s estimated that about half of all cancers can be prevented by following the advice for healthy living: not smoking, maintaining a healthy weight, exercising several times a week, and eating a diet high in fibre, fruits and vegetables.

Some cancers, like thyroid and testicular, are very treatable and have five-year net survival rates of over 90 per cent.

Other forms have poorer outlooks. Pancreatic cancer has the lowest survival rate of all the major cancers, at only 8 per cent. Very little progress has been made against this cancer, especially compared to other major cancers. As a result, it is expected to soon be the third leading cause of cancer death in Canada.

Cancer is complex, and developing effective treatments requires comprehensive study. Dr. Jolie Ringash, a radiation oncologist and researcher at Princess Margaret Cancer Centre, says the “sobering” new statistic underscores the importance of supporting research.

“It’s not one disease, it’s actually many diseases. And every time we hear a breakthrough, there’s always a great deal of hope that this is going to be the silver bullet that will end cancer. But ultimately what we find is each one of these advances will help a certain group of people, a certain group of diagnoses, but not everyone,” Ringash told CTV News Channel on Tuesday.

“So we need to be able to do the research in all of the different areas of cancer where there is a need.”

Smith says there is a lot Canadians can do to help protect themselves from cancer.

“With lung cancer, for example, it’s all about tobacco control. So if you smoke, quit. If you have a loved one who smokes, support them in quitting. There are a lot of great programs out there to help with that,” she said.

With other forms of cancer such as breast, colorectal, and cervical cancer, screening can help catch cancer early.

“We have great screening programs across Canada so it’s really important to get screened according to the recommendations,” she said.

Smith says a lot of progress has been made already to understand the different forms of cancer and research continues.

“There is a lot we can do. Prevention is absolutely key. And research continues to improve the outlook for people who have been diagnosed with cancer,” she said.

THE 4 MOST COMMON CANCERS IN CANADA

Lung cancer continues to make up the bulk of Canadian cancer cases (14 per cent), and remains the leading cause of cancer death in Canada, according the latest data from the Canadian Cancer Society. Lung cancer alone is expected to kill more Canadians this year (21,100) than colorectal, breast and prostate cancer combined (18,500).

Colorectal cancer is the second most common cancer overall, accounting for 13 per cent of all cancers diagnosed in Canada. It is the number two most common form for men, and the third most common form among women. Improvements to screening, diagnosis and treatment are leading to fewer deaths, according to the Canadian Cancer Society.

Breast cancer is the most commonly diagnosed form for Canadian women, impacting one in eight over the course of their lives. The latest estimates project 26,300 women will be diagnosed in 2017, and 5,000 of that group will die of the disease. However, the Canadian Cancer Society notes better screening and treatment has cut the rate of breast cancer deaths by 44 per cent since 1988.

Prostate cancer is the number one form diagnosed among men, impacting one in seven. The Canadian Cancer Society estimates 21,300 men will be diagnosed in 2017, and expects 4,100 will die. Like many of the other forms, the death rate is said to be on the decline due to improving treatments.