Renal cell carcinoma (RCC) that arises in the native kidneys of patients with end-stage renal disease (ESRD) exhibit more favorable features in kidney transplant recipients than in dialysis-only patients, according to a new study.
The study, led by Marc Gigante, MD, PhD, Chief of Urology and Kidney Transplantation at Félix Guyon University Hospital in Saint-Denis de la Réunion, France, examined 303 RCC cases that developed in ESRD patients. Transplanted patients accounted for 213 RCC cases (70.3%) and dialysis-only patients accounted for 90 (29.7%). RCC was diagnosed at a significantly earlier age in transplant recipients than dialysis-only patients (53 vs. 61 years). Transplant patients had a significantly smaller mean tumor size (3.4 vs. 4.2 cm) and a significantly higher frequency of pT1a stage tumors (75% vs. 60%), the investigators reported online in BJU International. Transplanted patients also had a significantly higher rate of a papillary RCC (44% vs. 22%) and a significantly lower rate of clear cell RCC (50% vs. 77%). Nodal and distant metastasis rates were significantly higher in dialysis-only patients.
In addition, the five-year cancer-specific survival rates were 97% and 77% for transplanted and dialysis-only patients, respectively. The five-year progression-free survival rates were 88% and 52%, respectively. After controlling for multiple variables, only T stage remained an independent predictor of cancer-related death.
Dr. Gigante’s group said earlier diagnosis of RCC in transplant recipients is the main hypothesis to explain their findings.
“Transplanted patients were likely to have their native kidneys monitored by a surgeon more frequently than dialysis-only patients,” the researchers stated. In French centers, they noted, urologists perform surgical monitoring of renal transplant patients and nephrologists follow dialysis patients.
The authors pointed out, however, that transplanted and dialysis-only patients differed in their RCC pathologic subtypes, suggesting differences in the tumorigenesis process.