Organ transplant recipients are at a heightened risk of aggressive melanoma – up to twice as likely – as compared to people who do not undergo such a transplant, a research has suggested.
Researchers led by a Johns Hopkins Bloomberg School of Public Health student have also suggested that transplant recipients are three times more likely to die of the dangerous skin cancer.
The primary reason behind this heightened risk of melanoma is the use of immunosuppressive medications specifically the high doses administered at the time of transplant. Researchers say that these immunosuppressants may make patients more susceptible to later stage cancers that are harder to cure.
Further, researchers also found that transplant recipients were four times more likely to be diagnosed with regional stage melanoma, which has already begun to spread to other parts of the body.
For their research, Hilary A. Robbins, MSPH, a PhD student in the Department of Epidemiology at the Bloomberg School who conducted much of the research while working at the National Cancer Institute and the team studied 139,991 non-Hispanic white transplant recipients in the Transplant Cancer Match Study, which is led by Eric A. Engels, MD, MPH, a senior investigator at the National Cancer Institute.
The study links the Scientific Registry of Transplant Recipients, which captures data on all transplants in the United States, with 15 population-based cancer registries, and includes information on almost half of the country’s transplant population between 1987 and 2010. The researchers found 519 melanomas in this group and analysed risk factors for developing melanoma.
Using a different data set, the researchers compared outcomes among 182 melanoma patients in the transplant group with more than 130,000 other people with melanoma. Over 15 years, 27 percent of the transplant recipients died of their melanoma, as compared to 12 percent of the non-recipients. The researchers found that melanoma patients who had received a transplant were three times more likely to die from their melanoma, even for melanomas that were diagnosed at an early stage or were very small.
The researchers found that the late-stage cases of melanoma were associated with use of medication given at the time of transplant that essentially stops T-cells — the main cells of immune response — from functioning in order to keep them from attacking the new organ. Meanwhile, early-stage melanomas were more likely to be found in recipients who were administered a medication called azathioprine, a maintenance drug given long term to some transplant recipients. This drug is known to multiply the effects of ultraviolet radiation, which could lead to the development of melanoma.
Robbins says her group’s findings suggest that transplant candidates should be screened very carefully for skin cancers before receiving their transplant. She says it is possible that some of the melanomas could have been present at the time of transplant, but that immunosuppressive drugs allowed them to spread unchecked. She also says that closer monitoring after transplant could allow melanoma to be detected earlier, preventing patients from developing deadly metastatic cancer.
The study has been published in the Journal of Investigative Dermatology.
