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SYDNEY - Aids sufferers and transplant patients are much more likely to contract about 20 different cancers than other people, breakthrough Australian research shows.
A landmark study by the University of New South Wales has revealed that immune deficiency - a problem common to the two groups - makes people more vulnerable to infections and the cancers they cause.
The cancers include liver, stomach, skin, lung, cervix, eye, lip, mouth and penis.
The results have implications for treatment, with researchers saying HIV patients should go on anti-retroviral drugs sooner to help avoid the cancer hazard.
Study leader Andrew Grulich, of the National Centre in HIV Epidemiology and Clinical Research, and colleagues analysed cancer rates in people with HIV and those who have had a kidney transplant and found a "marked increased risk".
Both groups have impaired immunity which appeared to put them at higher risk of catching viruses and developing cancers linked to them.
The research, published today in the prestigious British journal, The Lancet, showed that HIV/Aids patients were 11 times more likely to develop Hodgkin's lymphoma - a cancer associated with Epstein Barr Virus.
Transplant patients had a four-fold risk.
They also had more chance of contracting cancers relating to the human papilloma virus like cervical, penile and anus cancers.
Liver cancer rates were fivefold among HIV patients and double in transplant patients.
The dangers were similar for cancer of the lung, stomach, eye, larynx, lip and oesophagus.
They found no increased risk among more common, non infection-related cancers such as breast and prostate cancer.
Previous research has linked three cancers to HIV but it was thought the risk was fuelled by lifestyle. This is the first study to compare the rates in two vastly different groups with the one shared problem.
"The only thing that people with Aids and transplant recipients share is immune deficiency, otherwise their risk factors for cancer differ markedly," Prof Grulich said.
"This strongly suggests to us that it's the immune situation rather than an lifestyle issues that are behind this."
He said the results could have implications for the way HIV/Aids patients are treated.
"We need to maintain people's immune systems at a higher level, and that might mean putting HIV patients on anti-retroviral drugs earlier than is currently the case," Prof Grulich said.
New drugs also need to be developed for transplant patients that stop organ rejection but don't suppress the immune system so heavily.
The researchers now plan to look at those with congenital immune deficiency and people who have received other transplanted organs like heart and liver.
- AAP
