Impact of HLA Antigen Mismatches on Skin Cancer Risk in Transplant Recipients
Posted: Friday, February 22, 2019
A positive aspect of mismatched HLA antigens between donor and recipient in heart and lung transplants, researchers have found, is that such mismatching may be associated with a reduced risk of the recipient developing skin cancer, either squamous cell or melanoma. The retrospective cohort study, by Yi Gao, MD, of Banner University Medical Center, Phoenix, and colleagues also revealed that recipients of liver, kidney, and pancreas transplants did not benefit similarly.
The team undertook a secondary analysis of 10,649 patients who underwent a primary solid-organ transplant in 2003 or 2008 and were part of the multicenter Transplant Skin Cancer Network study, the authors described in JAMA Dermatology. In terms of hazard ratios, HLA-DR mismatches—but not HLA-A or HLA-B mismatches—were found to be statistically significant in impacting skin cancer risk.
For each additional mismatched allele, a 7% to 8% reduction in skin cancer risk was found through the standard antigen and broad specificity mismatch methods (P = .01 and P = .008, respectively). The CREG (cross reactive group) mismatch method did not yield similarly significant results.
“In the setting of a highly immunogenic transplanted organ, elevated levels of immunosuppression may increase the overall risk of skin cancer,” the investigators explained. However, “potential tumor surveillance mechanisms that remain intact despite immunosuppression may be more active in protecting heart and lung recipients with a higher level of HLA antigen mismatch.”
Accordingly, Dr. Gao and colleagues included a message for “internists and dermatologists who treat organ transplant recipients: [B]e aware that the risk of skin cancer may be higher in patients who underwent thoracic transplant and received a well-matched organ.”
Disclosure: The study authors’ disclosure information can be found at jamanetwork.com.