title: Mononuclear cell infiltration in clear-cell renal cell carcinoma independently predicts patient survival.
abstract: BACKGROUND
  The impact of mononuclear cell infiltration on renal cell carcinoma (RCC) biology has been controversial, previously reported to be associated with either a favorable or unfavorable prognosis. The objective of the current study was to evaluate associations between mononuclear cell infiltration in routinely prepared paraffin-embedded specimens with survival in patients with clear-cell RCC.
  
  
  METHODS
  A total of 306 patients were identified treated with nephrectomy for clear-cell RCC between 1990 and 1994. A single urologic pathologist, blinded to patient outcome, reviewed the specimens and quantified the extent of mononuclear cell infiltration as absent, focal, moderate, or marked. Cancer-specific survival was estimated using the Kaplan-Meier method. Associations of mononuclear cell infiltration with death from RCC were assessed using Cox proportional hazards regression models.
  
  
  RESULTS
  At last follow-up, 173 of the 306 patients studied had died, including 96 patients who died from RCC. Mononuclear cell infiltration was absent in 165 (54%), focal in 70 (23%), moderate in 53 (17%), and marked in 18 (6%). Univariately, patients with specimens that had mononuclear cell infiltration were over 2 times more likely to die from RCC compared with patients whose specimens exhibited no mononuclear cell infiltration (risk ratio, 2.63; P < .001). After adjusting for the Mayo Clinic SSIGN (stage, size, grade, and necrosis) score, patients with specimens that had mononuclear cell infiltration exhibited a significantly increased likelihood of dying from RCC compared with patients whose specimens had no mononuclear cell infiltration (risk ratio, 1.61; P = .028).
  
  
  CONCLUSIONS
  Mononuclear cell infiltration is associated with death from RCC even after multivariate adjustment. Routine documentation of mononuclear cell infiltration is recommended during the pathologic assessment of RCC.
authors.affiliation: Department of Urology, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: W Scott
authors.initials: WS
authors.lastname: Webster
authors.forename: Christine M
authors.initials: CM
authors.lastname: Lohse
authors.forename: R Houston
authors.initials: RH
authors.lastname: Thompson
authors.forename: Haidong
authors.initials: H
authors.lastname: Dong
authors.forename: Xavier
authors.initials: X
authors.lastname: Frigola
authors.forename: Demetrius L
authors.initials: DL
authors.lastname: Dicks
authors.forename: Shomik
authors.initials: S
authors.lastname: Sengupta
authors.forename: Igor
authors.initials: I
authors.lastname: Frank
authors.forename: Bradley C
authors.initials: BC
authors.lastname: Leibovich
authors.forename: Michael L
authors.initials: ML
authors.lastname: Blute
authors.forename: John C
authors.initials: JC
authors.lastname: Cheville
authors.forename: Eugene D
authors.initials: ED
authors.lastname: Kwon
mesh_terms: D002292:Carcinoma, Renal Cell / Q000401:mortality / Q000473:pathology*; D002452:Cell Count; D018450:Disease Progression; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality / Q000473:pathology*; D007963:Leukocytes, Mononuclear / Q000473:pathology*; D009392:Nephrectomy; D011237:Predictive Value of Tests