Transplants and cancer risks linked

People who have gotten kidney transplants appear to face a big increase in risk for a variety of cancers, particularly those caused by a virus.

Researchers writing in the Dec. 20 issue of the Journal of the American Medical Assn. tracked cancer incidence from 1982 to 2003 in nearly 29,000 Australians who got kidney transplants after serious kidney disease.

They excluded nonmelanoma skin cancer and cancers already known to lead to end-stage kidney disease and found that the patients experienced an overall cancer risk nearly 3.3 times higher after getting a kidney transplant than before.

Claire Vajdic of the University of New South Wales in Sydney, Australia, and lead author of the study, said the findings did not challenge the life-saving value of kidney transplantation for people with end-stage renal disease, noting the risk of dying was four times higher in patients remaining on dialysis than in those who get a transplant.

The study found that the risk for 18 kinds of cancer increased by at least three-fold, and 13 of these cancers are known or suspected to have a viral cause.

Immune system suppression, rather than the organ transplantation itself, is most likely responsible for the increase in cancer risk, Vajdic said.