title: Prevalence of microscopic tumors in normal appearing renal parenchyma of patients with hereditary papillary renal cancer.
abstract: OBJECTIVE
  We describe the earliest renal lesions associated with hereditary papillary renal cancer and estimate the prevalence of microscopic papillary renal tumors.
  
  
  METHODS
  Grossly normal tissue was obtained from 12 kidneys during renal surgery in 9 patients with hereditary papillary renal cancer. Tissue was examined microscopically and findings were compared to those previously reported to be associated with von Hippel-Lindau disease and sporadic renal cell carcinoma.
  
  
  RESULTS
  A total of 92 microscopic papillary renal cell carcinoma lesions were identified on 46 of 88 slides (53%). No other lesions were identified. All tumors were solid and displayed the basophilic papillary histology characteristic of hereditary papillary renal cancer. Extrapolation of the data predicted the prevalence of 1,100 to 3,400 microscopic papillary tumors in a single kidney in a patient with hereditary papillary renal cancer.
  
  
  CONCLUSIONS
  The basophilic papillary histology characteristic of clinically apparent renal tumors in patients with hereditary papillary renal cancer also characterizes the multiple microscopic lesions seen in the kidneys. These findings suggest that the earliest renal tumor in patients with an activating hereditary mutation of the met gene is papillary basophilic renal cancer. The large number of microscopic tumors in patients with hereditary papillary renal cancer was comparable to or greater than that seen in those with von Hippel-Lindau disease.
authors.affiliation: Urologic Oncology Branch, Laboratory of Pathology, and Biostatistics and Data Management Section, National Cancer Institute, Bethesda, Maryland, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Ornstein
authors.forename: I A
authors.initials: IA
authors.lastname: Lubensky
authors.forename: D
authors.initials: D
authors.lastname: Venzon
authors.forename: B
authors.initials: B
authors.lastname: Zbar
authors.forename: W M
authors.initials: WM
authors.lastname: Linehan
authors.forename: M M
authors.initials: MM
authors.lastname: Walther
mesh_terms: D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015995:Prevalence