Development renal cell carcinoma (RCC) in patients on long-term dialysis is associated with older age, male gender, acquired renal cysts, and end-stage renal disease caused by obstruction, tuberous sclerosis, and focal segmental glomeruloscerosis (FSGS), according to a study published online in Urology.
Rahul M. Jindal, MD, of Walter Reed Army Medical Center in Washington, DC, and his colleagues analyzed data from the United States Renal Data System (USRDS) to determine the incidence, risk factors, and prognosis of RCC in a national population of patients receiving incident long-term dialysis. The researchers identified 495,604 Medicare primary dialysis patients from January 1, 1997 to June 30, 2005. A total of 6,132 patients were diagnosed with RCC during the study period.
In adjusted analyses, male patients were at 63% increased risk of developing RCC than female patients. Acquired cysts and tuberous sclerosis were associated with 4.0 and 4.8 times increased risk of RCC. Obstruction and FSGS were associated with a 45% and 85% increased risk, respectively.
In addition, RCC risk increased with increasing age. For example, compared with patients aged 1-10 years, patients aged 41-50, 51-60, and 61-70 were at 5.8, 8.3, and 11.8 times increased risk, respectively.
Autosomal dominant polycystic kidney disease, dialysis modality, and smoking were not associated with post-dialysis RCC.
Noting that most cases of RCC diagnosed were not associated with documented acquired renal cystic disease, the authors wrote that “a screening strategy based on the presence of preexisting cysts would miss the vast majority of new cases of RCC in this population.”
Moreover, RCC was independently associated with increased risk of mortality regardless of subgroup. “This challenges the assumption that RCC is often an incidental and benign finding in this population,” the researchers concluded.