Cigarette smoking and acute nonlymphocytic leukemia.

In a case-control study of acute nonlymphocytic leukemia in western Washington state, cigarette smokers experienced a twofold increased risk of acute nonlymphocytic leukemia compared with nonsmokers. Risk increased significantly with the number of pack-years smoked (p = 0.0008) and decreased with the number of years stopped smoking (p = 0.15). The increased risk in smokers appeared to be limited to those who inhaled into the chest. The authors suggest that further studies of this potential relation are warranted, especially since the prevalence of cigarette smoking is relatively high in our society.