# Incidence of Malignancy and Risk Factors Associated with Kidney Transplant Patients

## TL;DR

This study finds that kidney transplant patients have a 9.6% risk of developing cancer, with older age and male sex as key risk factors.

## Contribution

The study identifies specific risk factors and incidence rates for post-transplant malignancies in a large cohort of kidney transplant recipients.

## Key findings

- The overall incidence of post-transplant malignancy was 9.6% per 1,000 patients.
- Incidence rates increased significantly with age, reaching 29.3% for those over 50.
- Male sex, older age, and a history of underlying diseases were significant risk factors for malignancy.

## Abstract

Background: The incidence and risk factors associated with the development of
post-transplant malignancies contributes to increased morbidity among kidney
transplant recipients were examined in this study. Materials and Methods: A
retrospective cross-sectional analysis was conducted to evaluate the medical
records of all kidney transplant recipients at Urmia Imam Khomeini Hospital from
January 2000 to December 2020. Patients were stratified into two groups based on
the presence or absence of post-transplant malignancy. Demographic data,
comorbidities, cancer history, and immunosuppression regimens were collected and
compared between the groups. Statistical significance was determined using
appropriate tests, including the t-test, Mann-Whitney test, Pearson chi-square
test, and Fisher exact test. All analyses were performed using SPSS 21, and a
P-value of less than 0.05 was considered statistically significant. Results: Of
the 4070 kidney transplant recipients, 3042 (74.7%) were male and 1028 (25.3%)
were female. The mean age at malignancy diagnosis was 53.78 years (standard
deviation ± 14.24). The overall incidence of post-transplant malignancy was 9.6%
per 1,000 patients (95% confidence interval: 9.6-13.2). Incidence rates varied
significantly by age group: 4.6% for those younger than 30, 7.6% for those aged
30-50, and 29.3% for those older than 50 (P0.001). A small percentage of
patients (n=3, 7.7%) required the addition of antithymocyte globulin (ATG) to
their primary immunosuppression regimen. The most commonly used
immunosuppressive regimens were prednisolone in combination with either
sandimune and azathioprine or sandimune and cellcept, employed in 35.9% of
patients. The most common underlying causes of kidney failure were
glomerulonephritis (GN) and hypertension (HTN), accounting for 38.5% and 35.9%
of cases, respectively. Conclusion: Kidney transplant recipients demonstrated a
higher incidence of post-transplant malignancies. Male sex, older recipient age,
and a history of underlying diseases were identified as significant risk factors
for malignancy development. The primary cause of kidney failure among the
patients was GN, followed by HTN.