Introduction: Kidney transplantation in patients with end-stage kidney disease improves quality of life and is associated with an increase in survival rates. Malignancies are one of the three major causes of renal recipient´s death with a functioning graft after cardiovascular diseases and infections. The incidence of post-transplant malignancies (PTM) varies between 2.0 and 30%, depending on the characteristics of the population.

Aim of study: The aim of this study is to analyze the incidence of PTM in solid organs and organs with hematological origin, excluding non-melanoma skin tumors, in kidney transplant recipients, as well as to evaluate factors associated with global survival in a single center.

Materials and methods: Retrospective observational cohort study. Data of 2,146 medical records that underwent kidney transplantation from deceased or living donors between 2000 and 2015 were analyzed.

Results: The cumulative incidence of PTM de novo was 5.5% with a mean follow-up of 9 years. During this period, 118 cases of PTM were reported, 103 in solid organ and 15 with hematological origin. The most frequent malignancy was kidney cancer, followed by malignant lung, prostate cancer and nonHodgkin lymphoma. Patients who developed PTM had a lower overall survival compared to those without malignancy (12.2 vs 18.2 years, p <0.001), and for recipients with PTM of hematological origin, mortality was higher in relation to those with solid organ neoplasms (p = 0.03). PTM is an independent risk factor for death in the post-transplant period (HR = 4.75, 95% CI: 3.52 –6.43; p <0.001), as well as the age of the recipient and donor above 60 years.

Conclusion: The incidence of renal PTM was 5.5%, with renal neoplasia being the most frequent. PTM was an independent prognostic factor for the patient's death, being that of hematological origin associated with higher mortality.