Malignancy is a main cause of mortality and morbidity for kidney transplantation recipients. Improvement in cancer surveillance and treatment may have an impact on the incidence and prognosis. This study was aimed to investigate the incidence and trends for post-transplantation malignancy.

We performed a population-based study on the TriNetX network. Common post-transplantation malignancies were identified. We evaluated the trends and prognosis for post-kidney transplantation malignancy over the past two decades (2000-2010 and 2011-2021).

A total of 184,267 patients undergoing kidney transplantation between 2008 and 2023 in were included. Among these patients, 30, 545 (16%) had developed malignancy after kidney transplantation. Patients with kidney transplantation were associated with a higher risk of malignancy [standardized incidence ratio 1.635, 95% confidence interval (CI) 1.6-1.67] and mortality [hazard ratio (HR) 1.115 95% CI 1.071-1.763 P < 0.0001] compared with the general population after propensity score match for age, gender, and race. The overall cancer incidence did not change significantly over the past two decades. Graft failure (HR 0.442 95% CI 0.413-0.473, P < 0.0001) and overall mortality rates (HR 0.755 95% CI 0.713-0.801, P < 0.0001) decreased significantly for all and common malignancy in the recent decade.

Patients receiving kidney transplantation had a higher risk of developing malignancy with a decrease of graft and patient survival. There was no significant change in post-transplantation malignancy incidence over the past two decades. Graft failure and mortality decreased in the recent decade for recipients with post-transplantation malignancy.