Patients who have received organ transplants have a very high risk of developing squamous cell skin cancer (a 65- to 250-fold increased risk as compared with the general population). Use of systemic immunotherapy drugs (drugs such as PD-1 inhibitors that cause body-wide immune activation) is risky for these patients, since the immune activation associated with these therapies can cause organ rejection. A study conducted in 2020 that evaluated the impact of systemic immunotherapy in patients with cancer showed that more than a third (37%) of treated patients experienced organ rejection, and 14% died as a result of the organ rejection. (See Fisher 2020 article in RESOURCES FOR SQUAMOUS CELL SKIN CANCER).
65 to 250
Investigators are studying various therapies specifically in organ-transplant recipients at risk for or diagnosed with squamous cell skin cancer. While some studies are evaluating existing immunotherapies, others are focused on therapies that are delivered directly into the tumor, such as oncolytic viruses (as described more extensively in the THERAPIES IN DEVELOPMENT page). Such therapies theoretically may be able to spark a localized immune response in the tumor without causing immune activation throughout the body, which can cause damage to the transplanted organ. The oncolytic immunotherapy RP1 is being studied in this setting. Additional studies in transplant recipients are being conducted with other systemic therapies that act more directly on the cancer cells (for example, targeted therapies that are directed at key cell pathways in the cancer cells as well as chemotherapy drugs that target actively dividing cells like cancer cells). Finally, there are studies of drugs to prevent skin cancer development in organ-transplant recipients. For a review of studies focused on squamous cell skin cancer in organ-transplant recipients, please see Search of: cutaneous squamous cell carcinoma and transplant – List Results – ClinicalTrials.gov