Endocrine Abstracts

Growth hormone (GH) raises serum levels of insulin-like growth factor (IGF)-I, which is mitogenic and antiapoptotic. There is evidence that raised endogenous levels of GH and IGF-I might be associated with increased risk of certain solid cancers, but there have been no data on long-term risks of solid cancers after GH treatment.
A cohort study was undertaken of cancer incidence and mortality in a cohort of 1848 patients in the UK who were treated in childhood and early adulthood with human pituitary growth hormone (hGH) during 1959-85 and were followed for cancer incidence to December 1995 and for mortality to December 2000. Risks of cancer in the cohort were analysed in comparison with that in the general population, controlling for age, sex and calendar period.
Patients treated with hGH had significantly raised risks of mortality from cancer overall (standardised mortality ratio 2.8 [95% CI 1.3 ? 5.1]; 10 cases), colorectal cancer (10.8 [1.3 ? 38.8]; 2 cases) and Hodgkin?s disease (11.4 [1.4 ? 41.3]; 2 cases); incidence of colorectal cancer was also greatly raised (7.9 [1.0 ? 28.7]). After removal from the cohort of patients whose original diagnosis rendered them at high risk of cancer, the significance and magnitude of the risks of colorectal cancer incidence and mortality and of Hodgkin?s disease mortality were increased.
Although based on small numbers, the risk of colorectal cancer is of some concern and needs evaluation in other cohorts. There is no evidence on whether GH in modern dosage regimens is associated with increased colorectal cancer risk.