Surgeons have to judge the suitability of donated organs but, with 7,000 waiting for a kidney, there is pressure to operate
The NHS patient information leaflet on kidney transplants does not mention transference of cancer as a risk factor. The only mention of the disease is to warn patients they cannot have a transplant if they have had a cancer that has spread to several parts of the body. The leaflet states that kidney transplants have a greater chance of long-term success if the donor is alive, and that one from a close relative has less chance of being rejected.
NHS Blood and Transplant (NHSBT) in England and Wales said every donor was screened, taking into account the cause of death, medical history, lifestyle and information from relatives and family doctors.
Doctors checked the organs and the body cavities from which they were removed. Those transplanting organs also made checks.
"Questions and the outcomes of available investigations are reviewed in order to ascertain any history of cancer," a spokesman said.
Asked how often cancerous tissue or blood was transferred, the service said: "Rarely – between 1 in 500 and 5,000 [cases], according to the published reports. Sometimes it is not possible to detect these tumours before or at the time of retrieval."
The service is endeavouring to compile a register of donor-caused tumours. Up to now, it has recorded general outcomes of transplants but has not had clear information on the cause of cancer.
In a statement, NHSBT said: "A transplant may be the only possible treatment for some people, who would die without one. In a situation where there are not nearly enough organs available for the number of transplants required, it often comes down to a balance of risk and benefit. Surgeons are always making judgments about the suitability of donated organs and are faced with the dilemma that – for example – more patients would die if they didn't receive a transplant at all."
The service says 6% of people on waiting lists for kidney transplants die each year. For heart and lung patients, the figure is about 20% and for those awaiting a replacement liver, 15%.
The National Kidney Foundation, a charity for kidney patients, is more explicit about cancer. It says about a quarter of all patients who live more than 20 years after transplants will develop cancer because the body's immune system not only fights off "invaders" such as germs, but tries to prevent cancer. Suppression of the immune system after a kidney transplant can allow cancer to develop.
Risk of skin cancer, lymphoma and cancer of the neck of the womb are particularly increased after transplantation, with between 1% and 2% of all patients developing a lymphoma within a year of transplants.
The foundation's website states: "Some lymphomas will go away if the anti-rejection drugs are stopped, but this means that the transplant will be rejected and dialysis will be needed again. Some lymphomas will respond to drugs [chemotherapy] or X-ray treatment [radiotherapy], and anti-rejection drugs can be continued, perhaps in a reduced dosage." There is no specific warning of cancers being transferred by transplanted organs.
There is a shortage of donors and a long waiting list for transplants. Nearly 7,000 people in the UK are waiting for a kidney – nine in 10 of all those awaiting an organ transplant – with some living for years in pain and discomfort.
Living donor kidney transplants have become more common. There were 475 in 2004-05, 589 in 2005-06, 690 in 2006-07, 831 in 2007-08, 927 in 2008-09 and 1,038 in 2009-10. Up to 6 March, the figure for this year was 921. There had been 1,412 kidneys transplanted from dead donors.