Fewer Canadians would die from cervical, breast and colorectal cancer if organized screening programs were expanded across the country, said the Canadian Cancer Society.

"We would like to see them implemented as quickly as we can, because the longer it takes, the more lives we are losing," said Heather Logan, director of cancer control policy for the society, on Tuesday.

The society, which released its annual report, estimates 153,100 new cases of cancer will be diagnosed in Canada in 2006 and that 70,400 Canadians will die from the disease this year.

Screening individuals for specific types of cancers means earlier detection. Treatment is more likely to be effective when a cancer is caught early.

In other cases, screening can pinpoint problems before cancer develops - for example, it can identify pre-cancerous polyps in the case of colon cancer.

Logan said that a colorectal cancer screening program would be particularly effective.

"We could reduce the death rates from colorectal cancer by as much as 17 per cent if people between the ages of 50 and 74 were screened with a FOBT (fecal occult blood) test -- which is a test that detects blood in your stool that you can't see with your own eyes," she said.

Logan added, "This is a potentially significant drop in deaths from colorectal cancer."

Although some informal screening is taking place, there is no organized colorectal screening program in Canada, Logan said.

Currently no Canadian jurisdiction has an organized colorectal cancer-screening program in place, in spite of scientific evidence touting its value.

"We in Canada are a backwater with respect to colorectal cancer," Terry Sullivan, president and CEO of Cancer Care Ontario -- which is on the verge of launching Canada's first colorectal cancer screening program -- told The Canadian Press.

"We're not in a position to be proud of our screening rates for colorectal cancer."

The cancer society said that evidence suggests breast cancer deaths could be cut by one-quarter if 70 per cent of women in the target age group -- aged 50 to 69 -- underwent a clinical breast exam and screening mammogram every two years.

While every province and territory, except Nunavut, had an organized breast-screening program established by 2003, none of them have achieved the target of 70 per cent participation.

"While it's encouraging that the proportion of women in organized breast cancer screening programs has increased over time, in 2003 participation was only 34 per cent nationally," says Logan.

Dr. Marla Shapiro, a breast cancer survivor herself and host of CTV's Balance, said national screening programs are expensive but vital.

"When we look at the cost of treating cancer, the medication, the social expense, the emotional burden, a strategy to detect can only be economically better," she said.

Meanwhile, the society says that ad-hoc Pap test screening for cervical cancer has cut incidence rates by 50 per cent and death rates by 60 per cent since 1977.

The Pap test can identify pre-cancerous lesions that can then be treated, and can identify cancer at an early stage when treatment is most effective.

"Because of the long history of high-quality cervical cancer screening in Canada, the benefit achieved so far may be close to the maximum," said Logan.

"However, it might be possible to see even further reductions in both incidence and death for this cancer if all elements of an organized screening program are incorporated, which would include identifying opportunities to increase participation."

Canadian health officials recommend screening for breast, cervical and colorectal cancer for targeted age groups.

However, they do not recommend it for prostate, lung and ovarian cancers, because scientific evidence has not shown that screening for these types actually reduces the number of deaths.

For example, the prostate specific antigen or PSA test, cannot distinguish between prostate cancers that require treatment and those slow-growing forms for which the severe side-effects of treatment are not warranted.

Other trends in cancer incidence and death rates:

• Since 1988, the overall cancer death rate for Canadian men has been declining slowly because of falling death rates for lung, colorectal and other cancers.
• Since 1988, the overall cancer incidence rate for Canadian women has been increasing slowly (largely because of increasing lung cancer incidences), but may be stabilizing. Cancer death rates for women have declined slightly.
• Among women, lung cancer incidence and death rates have tripled since 1977.
• Prostate cancer incidence rates increased since 1990, predominantly as a result of increasing detection using the PSA test.
• Breast cancer incidence rates among women over 50 rose steadily, but gradually, between 1977 and 1992. The society believes this may be the result of an increase in the use of mammograms.
• However, since 1993, incidence rates have stabilized and death rates have declined steadily.
• Colorectal cancer death rates have declined for both men and women.
• In men, thyroid cancer and melanoma incidence rates are on the rise and, at a lesser rate, testicular cancer and non-Hodgkin lymphoma.
• Among women, thyroid cancer incidence rates are escalating and, at a lesser rate, melanoma incidence rates.

With a report from CTV's Genevieve Beauchemin and files from The Canadian Press