Atypical epithelial proliferations in acquired renal cystic disease harbor cytogenetic aberrations

Acquired renal cystic disease (ARCD) complicating end-stage renal failure confers an increased risk for renal cell carcinoma, and atypical epithelial proliferation in the cysts may represent the precursor lesion. In this report we used an interphase cytogenetic technique to analyze the karyotypic features of various forms of atypical epithelial proliferations in a patient with ARCD. Both kidneys harbored numerous simple and atypical cysts. In addition, papillary tufts and a hitherto undescribed cribriform epithelial proliferation were found in the right kidney. The left kidney contained a 10-mm renal cell carcinoma with features indeterminate between clear cell and papillary types. There was gain of chromosome 7 in the papillary tufts; gain of chromosomes 7 and 17 in the cribriform lesion; gain of chromosomes 7, 12, 17, 20, and Y in the atypical cysts; and gain of chromosomes 7, 12, 17, and 20 in the renal cell carcinoma. These chromosomal aberrations suggest that atypical epithelial proliferations in ARCD represent early neoplastic lesions.