Medscape: Patients who receive organ transplants appear to be at increased risk for squamous cell carcinoma. In a brief report published in the September 3 issue of in the Journal of Clinical Investigation, Laurence Verneuil, MD, and colleagues from INSERM, University of Caen, France, give an explanation for this increased risk.
The report provides "the first evidence for donor contribution to the malignant epithelium of skin squamous cell carcinoma in a kidney transplant recipient," write Cai Bin Cui, MD, and David A. Berber, MD, from the School of Medicine at the University of North Carolina at Chapel Hill, in an accompanying commentary.
Tumor cells with donor genotype have previously been identified in human skin cancer after allogeneic transplantation, but it is unclear if donor tissue contributes to this cancer formation, Dr. Verneuil and his team write.
In 21 skin squamous cell carcinomas from kidney transplant recipients, the researchers examined p53 expression, which is found in squamous cell carcinomas, and TP53 mutations, which are found in tumor cells.
In 1 patient, they identified skin tumor cells that were the same genotype as the donated kidney and contained a mutation in a known cancer-causing gene. Cells with this mutation were present in kidney biopsy samples taken at the time of transplantation.
Important Implications for Cancer Research
This case study has implications for cancer research and the clinical care of transplant recipients, the editorialists explain.
"Cancer, especially skin squamous cell carcinoma, is a leading cause of mortality and morbidity in long-surviving kidney transplant recipients. Future research should address what can be done to reduce/prevent de novo malignancy and donor-associated malignancy in kidney transplant recipients," they write.
They also wonder if the findings from this report warrant inclusion of a cancer risk genetic test as part of transplant recipient and/or donor organ screening.
"Genetic factors are increasingly recognized to play important roles in tumorigenesis," they note. "Furthermore, genetic cancer risk screening of transplant recipients is potentially reasonable, since the cost and turnaround time for genetic testing is rapidly improving."
Currently, donor organ screening does not include genetic testing for cancer risk mutations, the editorialists point out.
The likelihood of such testing on donor organs "is remote at this point due to the extremely low prevalence of donor-associated malignancy, the long turnaround time, the high cost associated with the genetic tests, and the ever-increasing clinical shortage of donor organs," they write.
They conclude that the increase in long-term survival for transplant recipients and the knowledge of germline mutations and their association with cancer "brings us to a new clinical decision point."
"While the majority of post-transplant malignancies are likely to remain a de novo malignancy, we may be at the beginning of a time when we can risk assess the possibility of donor-associated malignancy development in a transplant recipient," they write.
Dr. Verneuil, Dr. Cui, and Dr. Gerber have disclosed no relevant financial relationships.