Increased Risk of Cancer After Pediatric Organ Transplantation

April 26, 2017, by DCEG Staff

A new analysis by researchers from DCEG shows a considerable increase in risk for several cancers following organ transplantation in childhood. Eric A. Engels, M.D., M.P.H., former DCEG fellow Dr. Elizabeth Yanik, and colleagues conducted the study using data from nearly 18,000 pediatric transplant recipients in the Transplant Cancer Match Study, making this the largest study of cancer in the pediatric transplant population to date.

Transplant recipients must utilize immunosuppressive medications to prevent rejection of the transplanted organ, resulting in weakened immune systems over the life span. The evidence on cancer risk in adult transplant recipients has been well-documented. However, in childhood, the immune system is still in development, and often children have not yet been exposed to some cancer-causing infectious agents. These factors, in addition to the many decades they are expected to live post-transplantation, makes this investigation particularly critical.

Overall cancer incidence among pediatric transplant recipients was over 19 times higher than that of the general pediatric population. The researchers found that the risk of non-Hodgkin lymphoma (NHL), the most common cancer in this population, was increased 212-fold. NHL risk was especially high during the first year following transplantation, as well as in individuals younger than five years of age and those receiving an intestine transplant. NHL risk was also very high in individuals who did not have antibodies to Epstein-Barr virus (EBV) at the time of transplantation, reflecting the effects of primary EBV infection following transplantation.

Pediatric transplant patients also experience relatively high risks of a number of other cancers, including Hodgkin lymphoma, myeloma, leukemia, and cancers of the liver, soft tissue, ovary, vulva, testis, bladder, kidney, and thyroid.

Given the strongly elevated risk for NHL, these results highlight the potential for substantial reduction in cancer risk among pediatric transplant patients if EBV infection can be prevented or controlled.

Reference: Yanik EL... Engels EA, et al. Cancer risk after pediatric solid organ transplant. Pediatrics. April 26, 2017. DOI: 10.1542/peds.2016-3893