title: Effect of papillary and chromophobe cell type on disease-free survival after nephrectomy for renal cell carcinoma.
abstract: BACKGROUND
  The clinical staging of renal cortical tumors traditionally has not evaluated the potential effect of histological subtypes on survival. Evidence suggests that conventional clear cell renal cell carcinoma (RCC) and nonconventional clear cell RCC (chromophobe and papillary) have different metastatic potential. Using a large renal tumor database, we examined the effect of tumor histology on the pattern of metastasis and patient survival.
  
  
  METHODS
  All patients with nonmetastatic renal cortical tumors undergoing partial or radical nephrectomy were identified from a renal tumor database between July 1989 and July 2002. Kaplan-Meier and Cox regression tests were used for statistical analysis.
  
  
  RESULTS
  Analysis revealed 1057 patients: 794 with conventional clear cell RCC, 157 with papillary RCC, and 106 with chromophobe RCC. Metastasis occurred in 95 conventional clear cell RCC, 9 papillary RCC, and 6 chromophobe RCC with a median follow-up of 34.6, 43.0, and 33.2 months, respectively. Using log-rank analysis, chromophobe and papillary RCC were associated with an improved disease-free survival at 5 years (P =.009 and.015, respectively). Multivariate analysis revealed tumor size, stage, and chromophobe histology as significant variables for disease progression.
  
  
  CONCLUSIONS
  Renal cortical tumors have distinct histological subtypes with varying degrees of metastatic potential. Conventional clear cell RCC, which comprises two thirds of renal cortical tumors presenting with localized disease, has a less favorable outcome when compared with papillary and chromophobe RCC. Controlling for size and stage, chromophobe, and not papillary, RCC was a significant variable for disease progression compared with conventional clear cell RCC. Knowledge of renal cortical tumor histological subtype is critical for projecting prognosis, tailoring follow-up strategies, and designing clinical trials.
authors.affiliation: Department of Urology, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
authors.forename: Stephen D W
authors.initials: SD
authors.lastname: Beck
authors.forename: Manish I
authors.initials: MI
authors.lastname: Patel
authors.forename: Mark E
authors.initials: ME
authors.lastname: Snyder
authors.forename: Michael W
authors.initials: MW
authors.lastname: Kattan
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Motzer
authors.forename: Victor E
authors.initials: VE
authors.lastname: Reuter
authors.forename: Paul
authors.initials: P
authors.lastname: Russo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D008175:Lung Neoplasms / Q000556:secondary; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009392:Nephrectomy; D016016:Proportional Hazards Models; D012189:Retrospective Studies