NEW YORK (Reuters Health) - Graphic warning labels on packs of cigarettes may convince some people that smoking ups the risk of bladder cancer, says a new study from Canada.
A survey of 291 people at doctors' offices in Toronto found less than half knew that smoking cigarettes is tied to an increased risk of bladder cancer, but three quarters said a graphic warning label would help raise awareness.
"Clearly patients do understand the association between cigarette smoking and lung cancer or chronic obstructive pulmonary disease, but we found in this little survey that only about 45 percent knew there was any risk of cigarette smoking associated with bladder cancer," said Dr. Robert Stewart, the study's senior author from St. Michael's Hospital in Toronto.
Bladder cancer is one of the most common cancers in U.S. men. The American Cancer Society estimates that 72,570 Americans will be diagnosed with bladder cancer in 2013 and 15,210 will die from it.
The researchers say that past research had suggested between 30 percent and 50 percent of all bladder cancers are caused by cigarette smoking.
In Canada, cigarette and little cigar manufacturers have to cover 75 percent of their product's packages with warnings that include graphic images of people with various cancers and conditions linked to smoking.
For the new study, published in The Journal of Urology, the researchers surveyed patients at a urology office and a family practice at St. Michael's Hospital between January and February 2011. Of 300 people who were given a survey, 291 returned them. About half were current or former smokers.
Overall, less than half knew a person's risk of bladder cancer was linked to smoking, compared to 98 percent who knew of a link between smoking and lung cancer.
After seeing a mock warning label that featured a graphic picture of a malignant bladder tumor, about 58 percent said it had changed their opinions on smoking and bladder cancer.
That meant the people were probably more convinced of the association - not that they would quit smoking, but about 75 percent thought the label would help get the message across, Stewart said.
He added that it's important to get people to quit smoking, because a person's risk of cancer will continue to fall over time.
According to the researchers, the risk of bladder cancer falls by about 40 percent about one to four years after a person quits smoking, and is back to average risk about 20 to 30 years after quitting.
"As time accumulates, the risks do fall off," Stewart said.
As of June 2012, cigarette manufacturers are required to display a number of new graphic warning labels on the packs of cigarettes they cell in Canada, according to Health Canada, the agency that regulates tobacco sales.
One of the labels warns buyers that "cigarettes cause bladder cancer," and features a picture of bloody urine, which is a symptom of the cancer.
A comment from Health Canada on how it selects which warnings to include on packaging could not be provided by deadline.
The U.S. Food and Drug Administration announced it would require similar labels on the cigarette packs it regulates, but recently abandoned that plan after legal challenges (see Reuters story of March 19, 2013 here: reut.rs/14yZgWD.)
SOURCE: bit.ly/ZZRSyY The Journal of Urology, online March 7, 2013.