Solid Organ Transplantation and Survival among Individuals with a History of Cancer.

BACKGROUND: The success of immunotherapy highlights a possible role for immunity in controlling cancer during remission for patients with cancer in the general population. A prior cancer diagnosis is common among solid organ transplant candidates, and immunosuppressive medications administered to transplant recipients may increase recurrence risk.
METHODS: Using linked data from the United States solid organ transplant registry and 13 cancer registries, we compared overall and cancer-specific survival among patients with cancer who did versus did not receive subsequent transplantation. We used Cox regression in cohort and matched analyses, controlling for demographic factors, cancer stage, and time since cancer diagnosis.
RESULTS: The study included 10,524,326 patients with cancer, with 17 cancer types; 5,425 (0.05%) subsequently underwent solid organ transplantation. The median time from cancer diagnosis to transplantation was 5.7 years. Transplantation was associated with reduced overall survival for most cancers, especially cervical, testicular, and thyroid cancers [adjusted hazard ratios (aHR) for overall mortality, 3.43-4.88]. In contrast, transplantation was not associated with decreased cancer-specific survival for any cancer site, and we observed inverse associations for patients with breast cancer (aHRs for cancer-specific mortality, 0.65-0.67), non-Hodgkin lymphoma (0.50-0.51), and myeloma (0.39-0.42).
CONCLUSIONS: Among U.S. patients with cancer, subsequent organ transplantation was associated with reduced overall survival, likely due to end-stage organ disease and transplant-related complications. However, we did not observe adverse associations with cancer-specific survival, partly reflecting careful candidate selection. IMPACT: These results do not demonstrate a detrimental effect of immunosuppression on cancer-specific survival and support current management strategies for transplant candidates with previous cancer diagnoses. ©2021 American Association for Cancer Research.