title: Significance of nuclear grade and tumor size in Korean patients with chromophobe renal cell carcinoma: a comparison with conventional renal cell carcinoma.
abstract: OBJECTIVE
  To analyze the clinical behavior of chromophobe renal cell carcinoma (RCC) in Korean patients.
  
  
  METHODS
  A total of 657 patients with conventional RCC and 71 with chromophobe RCC were included in the analysis. The median follow-up for all patients was 44 months (95% confidence interval, 10 to 126).
  
  
  RESULTS
  Patients with chromophobe RCC differed significantly from those with conventional RCC on the following parameters: a greater female ratio (P = 0.019), less advanced TNM stage (P = 0.004), and higher Fuhrman nuclear grade (P < 0.001). There was no statistical difference with regard to age and tumor diameter. The 5- and 10-year disease-specific survival rates in patients with chromophobe RCC (92.9% and 92.9%) were higher than in patients with conventional RCC (84.9% and 79.8%). When patients were divided according to T stage, Fuhrman's grade, and tumor size for the subgroup analysis, disease-specific survival probabilities of chromophobe RCC were higher in only tumors with a high Fuhrman's grade (G3/G4) (P = 0.002) and larger than 4 cm (P = 0.025). The multivariate analysis showed that the histologic type was not an independent predictor of disease-specific survival.
  
  
  CONCLUSIONS
  Although Korean patients with chromophobe RCC had a better survival probability than patients with conventional RCC, the histologic type was not an independent predictor of survival probability. In addition, our findings suggest that chromophobe RCC has a better survival probability than conventional RCC in patients with Fuhrman's grade 3 to 4 or with a tumor diameter > 4.0 cm.
authors.affiliation: Department of Urology, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Ja Hyeon
authors.initials: JH
authors.lastname: Ku
authors.forename: Kyung Chul
authors.initials: KC
authors.lastname: Moon
authors.forename: Cheol
authors.initials: C
authors.lastname: Kwak
authors.forename: Hyeon Hoe
authors.initials: HH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000473:pathology*; D002467:Cell Nucleus / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011379:Prognosis; D056910:Republic of Korea; D012189:Retrospective Studies; D015996:Survival Rate