But new research says that's exactly what's happening.
It's a startling finding: Almost one out of ten cancer survivors continues to smoke nearly a decade after being diagnosed, according to research from the American Cancer Society.
That's a big problem which could cause cancer to reoccur and makes treatments less effective.
Researchers already knew that some cancer patients continued to smoke after a diagnosis but they wanted to know how long that behavior continued.
For 9 years, researchers followed almost 3000 patients. They found that bladder and lung cancer survivors were the most likely to continue smoking. This group tended to be younger, to have less education and income, and were more likely to drink alcohol.
Researchers can't say why survivors keep smoking..the addictive quality of nicotine is certainly one factor--and researchers suspect patients might have a false sense of security when it comes to their health because they have lived so long after being diagnosed. .
To help reduce smoking among survivors experts suggest health care providers talk with cancer patients early on about the dangers of smoking. Following survivors long term could also help, as well as better access to smoking cessation programs.
(Holly Firfer for CNN's Health Minute)
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