Liver transplant recipients' cancer risk
Liver transplant recipients are more susceptible to cancer, especially skin cancers, new Flinders University research shows.
Of the 198 people who had a liver transplant or were managed post-transplant in South Australia between 1991 and 2010, a quarter of patients developed post-transplant malignancies, with skin cancer being the most common (16 per cent) and the remaining nine per cent being solid organ malignancies, including lymphoma, lung, prostate and colorectal cancer.
The study, undertaken by Flinders Professor Bogda Koczwara, SA Liver Transplant Unit Director Dr John Chen and Perth oncologist Hilary Martin, aimed to assess overall survival rates for patients with post-transplant malignancies.
The recipients were aged between 19 and 64 years, with the majority of patients being treated for liver failure due to cirrhosis.
Dr Chen, based at Flinders Medical Centre, said the reason liver transplant recipients incurred a greater risk of cancer was because of the side-effects of immunosuppressive drugs, which prevent the patient's body from rejecting the organ.
"When you perform a transplant you have to lower the patient's immunity so they don't reject the organ but there's a price to pay, and that price is an increased risk of infections and malignancies," Dr Chen said.
"Transplant rejection used to be a major problem in the past but we've significantly improved the process of immunosuppression – the only problem is the side-effects remain an issue," he said.
"While there's been a lot of work done to fine-tune these drugs to minimise the risk of infection and malignancies, we still need to work out the right combination for different patients."
The study showed recipients diagnosed with a skin cancer that could be treated locally had an excellent prognosis, with none of the patients developing disease progression, recurrence or dying from the skin malignancies.
Patients with solid tumours had substantially worse overall survival, at 47 per cent compared with the skin cancer group of 88 per cent during the follow-up period.
Of the patients with solid tumours, those suitable for local therapy alone had satisfactory outcomes, however those with advanced malignancies requiring systemic therapy experienced significant treatment-related toxicities and had poor outcomes.
Dr Chen said because transplants were so successful these days, recipients were living longer and therefore had an even greater vulnerability to cancer, which often occurs later in life.
Until scientists find a way to minimise the adverse effects of immunosuppression, he said transplant recipients required ongoing surveillance and monitoring.
"The main thing we can do is regular check-ups for skin cancers, and for patients who are at high risk of other cancers, such as smokers, we can survey the aerodigestive tract and for older patients we can do periodic colonic surveillance to look for large bowel tumours.
The study was published earlier this month in the Asia-Pacific Journal of Clinical Oncology.