De Novo Malignancies After Transplantation: Risk and Surveillance Strategies

De novo malignancies are one of the leading causes of late mortality after liver and kidney transplantation. Nonmelanoma skin cancer is the most common malignancy, followed by posttransplant lymphoproliferative disorder and solid organ tumors. Immunosuppression is a key factor for cancer development, although many other transplant-related and traditional risk factors also play a role. In this review, the authors summarize risk factors and outcomes of frequently encountered de novo malignancies after liver and kidney transplantation to stratify recipients at highest risk. Future efforts in prospectively validated, cost-effective surveillance strategies that improve survival of these complex patients are greatly needed.