Oct 12 (Reuters) - Younger people with advanced lung cancerwho quit smoking more than a year before their diagnosis survivelonger than those who continued smoking, according to a U.S.study.
However, quitters who were older or who had earlier stagesof lung cancer did not have an advantage, said the researchers,whose findings appeared in the journal Cancer.
It's known that people who never smoked are more likely tosurvive the disease, but whether former smokers do better thancurrent ones has been less clear.
"The findings do suggest there is some benefit to quittingsmoking," said Amy Ferketich of Ohio State University College ofPublic Health in Columbus, who worked on the study.
Her group used medical records from 4,200 lung cancerpatients treated at eight cancer centers around the country.
Patients who never smoked were more likely to survive theless advanced cancers - stage 1, 2 or 3 - than were former orcurrent smokers, the researchers found.
Among smokers with stage 1 or 2 lung cancer, for instance,72 percent survived at least two years, compared to 93 percentof the never-smokers and 76 percent of people who'd kicked thehabit a year or more before diagnosis.
Only 15 percent of smokers with stage 4 disease survived twoyears, while 40 percent of never-smokers and 20 percent offormer smokers did.
After adjusting the numbers for factors such as age, raceand radiation treatment, the researchers determined thatquitters were just as likely to die from the early-stage cancersas were current smokers.
But for advanced cancers, people under 85 who had stoppedsmoking more than a year before their diagnosis survived longerthan smokers. Forty-five-year-old former smokers, for instance,were 30 percent less likely to die from stage 4 lung cancerwithin two years than were current smokers.
Smoking is the number one risk factor for developing lungcancer, and studies have shown that people who quit are lesslikely to get it than current smokers, but it's not clear whysmokers already diagnosed with lung cancer fare worse thannon-smokers, Ferketich said.
"In general, never smokers are healthier individuals, sothey tend to, in a lot of trials, have better outcomes withdisease than people who continue to smoke," she said.
"Just the continued exposure to tobacco might make thedisease progress more quickly in smokers compared tonever-smokers who don't have that exposure."
Ferketich said it's also possible that smoking couldinfluence the biology of the cancer, and perhaps smokers gettumors that never-smokers are less likely to develop. She addedthat it's never too late to quit.SOURCE:
(Reporting from New York by Kerry Grens at Reuters Health;editing by Elaine Lies)
Keywords: HEALTH LUNGCANCER/