UK Study Supports Smoking Link to Leukemia
LONDON (Reuters) - Smoking can cause cell damage and changes in the body's immune system which could increase the risk of adult leukemia, British researchers said on Friday.
Scientists at the University of Leeds in northern England who examined the smoking history of more than 800 leukemia patients found that up to 10 percent of acute cases of the deadly blood cancer could be related to smoking.
The research, which is published in The British Journal of Cancer, supports previous studies linking smoking to leukemia.
``This is the biggest study of its kind and confirms what has been found before,'' Eleanor Kane, one for the researchers, said in a telephone interview.
The scientists said tobacco smoke contains harmful agents such as benzene, radioactive lead and polonium, nitrosamines and urethanes that are suspected causes of the disease.
``Benzene in large doses is known to cause leukemia. That might not be the full picture. There are other chemicals and it could be a combination of them,'' Kane added.
The researchers found the biggest risk of leukemia was in people who had smoked for at least 10 years. They estimate the habit could be responsible for as many as 200 cases of adult leukemia in Britain each year.
``Although the biological mechanisms are unknown, what is understood is that tobacco smoke leads to chromosomal defects in blood cells and immunological changes such as an increased leukocyte (white blood cell) count and decreases natural killer cell activity, factors which are linked to leukemia,'' said Kane.
But the researchers also had some good news.
Their study showed that people who give up smoking can reduce their risk of leukemia to normal levels within a year of quitting.
``Smoking is still not widely accepted as a cause of leukemia, especially by members of the public. This research provides yet further evidence of a major link between the habit and this life-threatening disease,'' Dr David Grant, of Britain's Leukemia Research Fund, said in a statement.