Patients with end-stage renal disease (ESRD) are at increased risk for urologic malignancies, according to a recent systematic review and meta-analysis of 19 observational studies involving 1,931,073 ESRD patients.
ESRD is associated with 6-fold and 4.4-fold increased risk of kidney cancer and urothelial cancers, respectively, compared with the absence of ESRD, investigators reported online ahead of print in Nephrology. Urothelial cancers included carcinomas of the bladder, ureters, and renal pelvis. The pooled estimated incidence of kidney cancer and urothelial cancers in ESRD patients were 0.3% and 0.5%, respectively, reported a team led by Panagiotis Kompotiatis, MD, of Mayo Clinic in Rochester, Minnesota, and Charat Thongprayoon, MD, of Bassett Medical Center in Cooperstown, New York.
The researchers noted that an association between ESRD and kidney cancer is well known, the risk of urothelial cancers in ESRD patients is unclear.
Epidemiologic studies, they stated, have identified risk factors for kidney cancer and urothelial cancers, including genetic factors, obesity, cigarette smoking, and exposure to chemical carcinogens such as aristolochic acid. In addition, some studies have found an association between kidney cancer and acquired cystic kidney disease (ACKD), which can occur in up to 50% of patients with ESRD on dialysis, the authors noted. According to the investigators, it has been proposed that the pathogenesis of ACKD in the ESRD population “is a consequence of the loss of a critical number of functioning nephrons with subsequent compensatory hypertrophy of the few survival nephrons. It is also presumed that the renal cysts arise by the weakening of the distal convoluted tubules or collecting ducts, with subsequent formation of diverticula and expansion into the cyst.”
In a discussion of study limitations, the authors acknowledged that because their meta-analysis included only observational studies, it can only establish an association between ESRD and urologic cancers, not causation. They also pointed out that it is possible urologic cancers were detected and diagnosed due to more intensive routine cancer screening among ESRD patients.
Kompotiatis P, Thongprayoon C, Manohar S, et al. Association between urologic malignancies and end-stage renal disease: A meta-analysis. Nephrology 2017; published online ahead of print.