title: Distribution of metastatic sites in renal cell carcinoma: a population-based analysis.
abstract: BACKGROUND
  We assessed the distribution of site-specific metastases in patients with renal cell carcinoma (RCC) according to age. Moreover, we evaluated recommendations proposed by guidelines and focused specifically on bone and brain metastases.
  
  
  METHODS
  Patients with metastatic RCC (mRCC) were abstracted from the Nationwide Inpatient Sample (1998-2007). Age was stratified into four groups: <55, 55-64, 65-74 and ≥ 75 years. Cochran-Armitage trend test and multivariable logistic regression analysis tested the relationship between age and the rate of multiple metastatic sites. Finally, we examined the rates of brain or bone metastases according to the presence of other metastatic sites.
  
  
  RESULTS
  In 11,157 mRCC patients, the rate of multiple metastatic sites decreased with increasing age (P < 0.001). This phenomenon was confirmed in patients with lung, bone, liver and brain metastases (all P ≤ 0.01). The rate of bone metastases was 10% in patients with exclusive abdominal metastases and 49% in patients with abdominal, thoracic and brain metastases. The rate of brain metastases was 2% in patients with exclusive abdominal metastases and 16% in patients with thoracic and bone metastases.
  
  
  CONCLUSIONS
  The proportion of patients with multiple metastatic sites is higher in young patients. The rates of bone (10%-49%) and brain (2%-16%) metastases are nonnegligible in mRCC patients.
authors: Department of Urology, Vita-Salute University, Urological Research Institute, Milan, Italy. bianchihsr@gmail.com
authors: M
authors: M
authors: Bianchi
authors: M
authors: M
authors: Sun
authors: C
authors: C
authors: Jeldres
authors: S F
authors: SF
authors: Shariat
authors: Q-D
authors: QD
authors: Trinh
authors: A
authors: A
authors: Briganti
authors: Z
authors: Z
authors: Tian
authors: J
authors: J
authors: Schmitges
authors: M
authors: M
authors: Graefen
authors: P
authors: P
authors: Perrotte
authors: M
authors: M
authors: Menon
authors: F
authors: F
authors: Montorsi
authors: P I
authors: PI
authors: Karakiewicz
mesh_terms: D000367:Age Factors; D000368:Aged; D001859:Bone Neoplasms / Q000556:secondary*; D001932:Brain Neoplasms / Q000556:secondary*; D002292:Carcinoma, Renal Cell / Q000556:secondary*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors