Prevalence of Colonic Polyps in Patients Undergoing Kidney Transplant Evaluation: A Meta-Analysis and Systematic Review

Objectives: Colorectal cancer is the third most common cancer worldwide, and kidney transplant patients have up to a 2.5-fold increased risk of colorectal cancer compared with the general population. Presently, colorectal cancer screening recommendations in kidney transplant candidates are the same as for the general population. We explored the literature on the prevalence of colonic polyps in patients with renal failure undergoing screening colonoscopy as part of kidney transplant evaluation. Materials and Methods: We conducted a systematic review in PubMed, Embase, and Cochrane databases from inception through June 2023 to identify studies that explored the prevalence of colonic polyps in patients with chronic kidney disease undergoing a screening colonoscopy as part of their pretransplant evaluation. Results: Of 937 patients, 371 had ≥1 polyp on their screening colonoscopy (39.6%; 95% CI, 29.3%-50.3%), 243 patients had ≥1 adenoma (25.9%; 95% CI, 14.3%-39.6%), and 75 had ≥1 high-risk adenoma (8.7%; 95% CI, 6.9%-10.7%). Pooled analysis of the 2 studies comparing patients with end-stage renal disease versus matched control groups indicated higher pooled prevalence of adenomas in the end-stage renal disease group (33.4%) versus the control group (23.9%). Conclusions: Our results suggest an average or increased prevalence of polyps and adenomatous polyps in patients with chronic kidney disease undergoing colonoscopy during evaluation for kidney transplant. The pooled analysis of the studies comparing the end-stage renal disease population versus a matched control group indicates higher prevalence of adenomatous polyps in patients with end-stage renal disease. Multiple studies have shown that screening colonoscopy in this patient group is safe and does not delay kidney transplant evaluation or wait list rates; hence, screening colonoscopy should be routinely considered.