Prospective pretransplant ultrasound screening in 206 patients for acquired renal cysts and renal cell carcinoma

Background. Numerous studies have reported an increased prevalence of renal cell carcinoma in association with acquired cystic kidney disease (ACKD), In 1995, the clinical practice guidelines of the American Society of Transplant Physicians for evaluation of renal transplant candidates recommend not screening for ACKD and renal cell carcinoma, on the basis of the low frequency of cancer and reported regression of ACKD after transplantation. The objective of this study was to prospectively evaluate the prevalence of ACKD and renal cancer during renal transplant evaluation. Methods. A total of 206 consecutive adult patients evaluated for renal transplantation underwent a routine renal ultrasound. Patients with a suspicions ultrasound underwent a contrasted computed tomographic scan of the kidneys followed by excision of kidneys with solid, enhancing (>10 Hounsfield units) lesions. Results. Sixty-three (30.6%) of 206 patients had ACKD, with a greater proportion being male, African-American, and dialysis-dependent for a longer duration. Eight patients (3.8%) had histologically proven localized cancer (six unilateral, two bilateral), seven in association with ACKD and one in association with autosomal dominant polycystic kidney disease. With a mean follow-up of 14 months (range, 3-33 mo), there has been no recurrence. The positive predictive value of a solid lesion on ultrasound was 100% (8 of 8 patients). Conclusion. With the high prevalence (3.4%) of renal cell carcinoma in association with ACKD and the concern that immunosuppression accelerates the growth of preexisting cancers, we continue to recommend ultrasound screening of the native kidneys before renal transplantation.