Transplant recipients more likely to die of cancer

Researchers suggest different screening and treatment strategies may be needed

Recipients of solid organ transplants — kidney, liver, heart or lung — are three times more likely to die from cancer than the general population, according to a new study from the Institute for Clinical Evaluative Sciences and St. Michael’s Hospital.

While it’s been known that transplant recipients are at higher risk for cancer, this study proves they are at increased risk of death from malignancy, says Dr. Nancy Baxter, senior author of the study published Thursday in JAMA Oncology.

The study suggests transplant recipients may require different cancer screening, surveillance and treatment strategies.

“The transplant doctors have done a fantastic job improving outcomes for these patients,” says Baxter, head of general surgery at St. Michael’s Hospital. “The cardiovascular community has done a terrific job reducing risks of death from heart disease. Now we need to focus on other things affecting their long-term outcomes.”

The increased cancer mortality may be due to the immunosuppressant drugs that allow the patient not to reject the organ. The suppressed immune system may not be able to fight the cancer from developing and may allow the malignancy to be more aggressive, says Baxter, a senior scientist at ICES. Transplant recipients are often on the drugs for life.

Once cancer develops, a transplant recipient may receive less aggressive treatment because of other existing health problems and the fear of possible transplant rejection, according to the study.

The study looked at health records for 11,061 solid organ transplant patients in Ontario between 1991 and 2010. Of those who died, nearly 20 per cent were from cancer, a rate three times higher than among the non-transplant population.

About 10 per cent of recipients had been diagnosed with a malignancy before the transplant, making them more likely to die from cancer. When researchers excluded this vulnerable group, the rate of death from cancer was still high, twice that of the general population.

Among all transplant recipients, lung cancer was the top cancer killer, as it is in the general population, says Baxter.

But the recipients were more at risk of death from a number of cancers, particularly non-Hodgkin’s lymphoma and skin cancer, than the broader population.

The issue of cancer and organ recipients is important for the future as transplant numbers increase, particularly among older people, who are more prone to cancer.

“In the past, transplants weren’t offered to people over 60, now they’re routinely offered,” says Dr. Atul Humar, director of the transplant program at the University Health Network.

“Our ability to treat people with severe organ disease is better and we don’t need to transplant until they are older. Our ability to transplant older patients and look after them is also better.”

For all ages, however, transplantation continues to be limited by organ availability. (To find out about organ donation, visit beadonor.ca.) The UHN program, Humar continues, tries to mitigate cancer risks with regular screening and encouraging patients to lead healthy lifestyles. Most recipients see a skin specialist for early signs of malignancy.

A heart recipient three years ago, Dave Allingham has gone from lying on the couch to being an avid cyclist. “The transplant gave me my life back,” says the 43-year-old father of two.

He exercises, eats right, uses sunscreen — and doesn’t lose sleep over health risks.

“You educate yourself about the risks and do what you need to do,” he says. “It’s a small price to pay for being here.”

“You educate yourself about the risks and do what you need to do. It’s a small price to pay for being here.” DAVE ALLINGHAM HEART RECIPIENT