title: Renal sinus fat invasion in pT3a clear cell renal cell carcinoma affects outcomes of patients without nodal involvement or distant metastases.
abstract: OBJECTIVE
  According to the 2002 American Joint Committee on Cancer TNM classification, perinephric and renal sinus fat invasion are classified as pT3a renal cell carcinoma. However, only a few studies have assessed the impact of sinus fat invasion on patient survival and with controversial results. We analyzed the impact of sinus fat invasion on cancer specific survival in a cohort of patients with pT3a clear cell renal cell carcinoma.
  
  
  METHODS
  We retrospectively analyzed data on 115 consecutive patients treated with open radical nephrectomy for unilateral, sporadic pT3a clear cell renal cell carcinoma at our department from 1989 to 2006. All pathological specimens were rereviewed by a single uropathologist. The prognostic role of sinus fat invasion in cancer specific survival was assessed by Cox proportional hazards regression models.
  
  
  RESULTS
  Ten patients had direct ipsilateral adrenal invasion and were excluded from analysis. A total of 105 patients with clear cell renal cell carcinoma were evaluated. Median followup was 38 months. In the overall population sinus fat invasion did not reach independent predictive status in terms of cancer specific survival on multivariate Cox regression analysis after adjusting for age, performance status, tumor dimension, tumor grade, synchronous metastases, nodal involvement, sarcomatoid differentiation and coagulative necrosis. In the subset of patients with pNx/pN0 M0 (83) the actuarial 5-year cancer specific survival was 71.9% and 45.5% for those with perinephric fat invasion only and sinus fat invasion, respectively (p = 0.025). Sinus fat invasion achieved an independent predictive role on multivariable Cox regression analysis (p = 0.048, HR 2.06).
  
  
  CONCLUSIONS
  Sinus fat invasion in clear cell renal cell carcinoma significantly affects cancer specific survival in patients without nodal or distant metastases. However, sinus fat invasion is not associated with worse cancer specific survival in cases of metastatic disease.
authors.affiliation: Department of Urology, Vita-Salute University San Raffaele, Milan, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bertini
authors.forename: Marco
authors.initials: M
authors.lastname: Roscigno
authors.forename: Massimo
authors.initials: M
authors.lastname: Freschi
authors.forename: Elena
authors.initials: E
authors.lastname: Strada
authors.forename: Giovanni
authors.initials: G
authors.lastname: Petralia
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pasta
authors.forename: Rayan
authors.initials: R
authors.lastname: Matloob
authors.forename: Francesco
authors.initials: F
authors.lastname: Sozzi
authors.forename: Luigi
authors.initials: L
authors.lastname: Da Pozzo
authors.forename: Renzo
authors.initials: R
authors.lastname: Colombo
authors.forename: Giorgio
authors.initials: G
authors.lastname: Guazzoni
authors.forename: Claudio
authors.initials: C
authors.lastname: Doglioni
authors.forename: Francesco
authors.initials: F
authors.lastname: Montorsi
authors.forename: Patrizio
authors.initials: P
authors.lastname: Rigatti
mesh_terms: D000273:Adipose Tissue / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002292:Carcinoma, Renal Cell / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D007682:Kidney Pelvis / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology*; D009367:Neoplasm Staging; D011336:Probability; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D016019:Survival Analysis