Enhancement of 7,12-dimethylbenz(a)anthracene leukaemogenesis in mice by neonatal injection of cortisone acetate.

LYMPHOID tumours originating in the thymus can be induced in a high incidence in Swiss mice when they are given a single injection of 7,12-dimethylbenz(a)anthracene (DMBA) shortly after birth (Pietra, Spencer and Shubik, 1959). Newborn animals are more susceptible to this leukaemogenic effect of DMBA than animals 2-4 months old (Toth, Rappaport and Shubik, 1963). It has been also demonstrated that there exists a strain difference in tumorigenic response t

Tobacco and the risk of acute leukaemia in adults

Self-reported smoking histories were collected during face-to-face interviews with 807 patients with acute leukaemia and 1593 age- and sex-matched controls. Individuals who had smoked regularly at some time during their lives were more likely to develop acute leukaemia than those who had never smoked (odds ratio (OR) = 1.2, 95% confidence interval (CI) 1.0–1.4). The association was strongest for current smokers, defined here as smoking 2 years before diagnosis (OR = 1.4, 95% CI 1.1–1.7). With respect to the numbers of years smoked, risk estimates were raised in all groups except those who had smoked for fewer than 10 years. Similarly, the odds ratio decreased as the number of years ‘stopped smoking’ increased, falling to one amongst those who had given up smoking for more than 10 years. No significant linear trends were found, however, with either the numbers of years smoked or the numbers of years stopped smoking, and no significant differences were found between AML and ALL. © 1999 Cancer Research Campaig