# Incidence of cancer in people with CKD not requiring kidney replacement therapy: a systematic review and meta-analysis

## TL;DR

People with chronic kidney disease have a higher cancer risk, especially as kidney function worsens and with increasing age.

## Contribution

This study provides the first comprehensive meta-analysis showing elevated cancer incidence in CKD patients not on kidney replacement therapy.

## Key findings

- Cancer incidence is significantly higher in individuals with eGFR <60 compared to those with eGFR ≥60.
- Age is positively associated with cancer incidence in CKD patients.
- No significant site-specific cancer associations were found in CKD patients.

## Abstract

Cancer incidence in people with chronic kidney disease (CKD) who do not require kidney replacement therapy remains inadequately characterized. This systematic review aimed to establish whether there is an elevated incidence of cancer in people with CKD.

A systematic search of three online bibliographic databases until 17 January 2023 identified studies reporting cancer incidence in CKD cohorts (PROSPERO CRD42022359690). Meta-analyses using inverse variance method compared incidence rates in individuals with low estimated glomerular filtration rate (eGFR) (<60 mL/min/1.73 m2) with available cohorts with normal eGFR (≥60 mL/min/1.73 m2 or both 60–89 and ≥90 mL/min/1.73 m2) for all cancers and site-specific cancers. Multiple meta-regression analyses explored associations of eGFR and age.

In 27 studies (5 519 778 people with CKD), from 10 countries spanning 2009–2022, incidence rates of cancer were associated with worse CKD severity. Incidence rate ratio (IRR) comparing people with an eGFR <60 mL/min/1.73 m2 vs ≥60 mL/min/1.73 m2 was 1.35 [95% confidence interval (CI) 1.12–1.63, P = .002, I2 = 99.9%]. People with eGFR <60 mL/min/1.73 m2 were at an elevated rate of cancer compared with eGFR ≥90 mL/min/1.73 m2 [IRR 1.48 (95% CI 1.04–2.10, P = .03, I2 = 100%)] and those with eGFR 60–89 mL/min/1.73 m2 [IRR 1.21 (95% CI 1.11–1.33, P < .01, I2 = 92%)]. Age was associated with increased cancer incidence (β = 0.31, P = .02) on multiple meta-regression analysis. There was no association between site-specific cancer incidence in CKD patients, but these had wide confidence intervals.

Individuals with CKD have an elevated incidence of cancer, with increasing age contributing to this association. These findings emphasize the importance of investigating whether CKD independently elevates cancer risk, building evidence for tailored cancer screening into CKD patient care.

Graphical Abstract