Fewer young men in Canada are being diagnosed with cancer but the number of young women afflicted is unchanged, according to a comprehensive report released Tuesday.

The national report by Cancer Care Ontario and the Public Health Agency of Canada looks at trends from 1983 to 1999 based on cancer registries, with projections to 2005, for people aged 20 to 44 — a previously understudied group.

There is a lot of speculation about why testicular cancer rates are increasing, but little evidence available, said Dr. Loraine Marrett.
(CBC)

"Incidence of a number of more common cancers is increasing, for example, thyroid cancer incidence is increasing in both men and women more rapidly than any other cancer, yet we don't have a clear understanding of why this is happening," said Dr. Loraine Marrett, director of the surveillance unit at Cancer Care Ontario.

While Marrett doesn't think there is enough evidence of an environmental link for thyroid cancer, Meg Sears, a biochemical engineer and science analyst in Ottawa disagrees.

"Old people may get cancers because their cells have reproduced so many times they've got genetic changes and then things go wrong," said Sears. "But when young people get cancer it's either because of an infection or because of something else that's toxic in the environment."

Part of the rise is attributed to better diagnosis of thyroid cancer, but that alone cannot explain the higher incidence of the malignancy, which is highly curable if detected early.

Thyroid cancer is thought to be caused by exposure to radiation, especially during childhood.

Overall cancer incidence rates for men have declined significantly since 1992, reflecting a drop in more common cancers for the age group such as melanoma, lung and colorectal cancer.

But testicular cancer, the most common cancer for young men, increased 2.2 per cent per year.

Testicular cancer may be overlooked in part because older people tend not to get it, said Geoff Eaton of St. John's, who survived two bouts of non-Hodgkin's lymphoma at the ages of 22 and 25. Eaton started a support group and charity for young adults with cancer.

For the first time, more young women than young men are being diagnosed with and dying from lung cancer, the report's authors found.

The findings show efforts to discourage young Canadians, especially young women, from smoking need to continue, said Heather Logan, director of cancer control policy at the Canadian Cancer Society.

Physical, emotional challenges

When a young person is diagnosed with cancer, they face physical and emotional changes at a time when they may be completing their education, getting jobs and building families, and may need more support, the report said.

"It kind of reminded me of having your wings clipped just when you're learning to fly on your own," said Julie Easley, of Fredericton, who was 23 when she was diagnosed with Hodgkin's lymphoma or cancer of the lymph system seven years ago.

Easley is now doing her PhD work on how a cancer diagnosis interrupts the lives of young people, causing financial problems, as well as affecting fertility and sexuality.

It's important to learn more about the long-term treatment risks and develop therapies to reduce late effects such as reproductive problems or a second cancer, said Dr. Brent Schacter, CEO of the Canadian Association of Provincial Cancer Agencies.