title: Chromophobe Renal Cell Carcinoma is the Most Common Nonclear Renal Cell Carcinoma in Young Women: Results from the SEER Database.
abstract: OBJECTIVE
  The renal cell cancer incidence is relatively low in younger patients, encompassing 3% to 7% of all renal cell cancers. While young patients may have renal tumors due to hereditary syndromes, in some of them sporadic renal cancers develop without any family history or known genetic mutations. Our recent observations from clinical practice have led us to hypothesize that there is a difference in histological distribution in younger patients compared to the older cohort.
  
  
  METHODS
  We queried the SEER (Surveillance, Epidemiology and End Results) 18-registry database for all patients 20 years old or older who were surgically treated for renal cell carcinoma between 2001 and 2008. Patients with unknown race, grade, stage or histology and those with multiple tumors were excluded from study. Four cohorts were created by dividing patients by gender, including 1,202 females and 1,715 males younger than 40 years old, and 18,353 females and 30,891 males 40 years old or older. Chi-square analysis was used to compare histological distributions between the cohorts.
  
  
  RESULTS
  While clear cell carcinoma was still the most common renal cell cancer subtype across all genders and ages, chromophobe renal cell cancer was the most predominant type of nonclear renal cell cancer histology in young females, representing 62.3% of all nonclear cell renal cell cancers (p <0.0001). In all other groups papillary renal cell cancer remained the most common type of nonclear renal cell cancer.
  
  
  CONCLUSIONS
  It is possible that hormonal factors or specific pathway dysregulations predispose chromophobe renal cell cancer to develop in younger women. We hope that this work provides some new observations that could lead to further studies of gender and histology specific renal tumorigenesis.
authors.affiliation: Department of Urology, State University of New York Upstate Medical University, Syracuse, New York.
authors.forename: Michael
authors.initials: M
authors.lastname: Daugherty
authors.affiliation: Department of Urology, State University of New York Upstate Medical University, Syracuse, New York.
authors.forename: Stephen
authors.initials: S
authors.lastname: Blakely
authors.affiliation: Department of Urology, State University of New York Upstate Medical University, Syracuse, New York.
authors.forename: Oleg
authors.initials: O
authors.lastname: Shapiro
authors.affiliation: Department of Urology, State University of New York Upstate Medical University, Syracuse, New York.
authors.forename: Srinivas
authors.initials: S
authors.lastname: Vourganti
authors.affiliation: Department of Urology, State University of New York Upstate Medical University, Syracuse, New York.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mollapour
authors.affiliation: Department of Urology, State University of New York Upstate Medical University, Syracuse, New York. Electronic address: bratslag@upstate.edu.
authors.forename: Gennady
authors.initials: G
authors.lastname: Bratslavsky
mesh_terms: D000328:Adult; D017677:Age Distribution; D002292:Carcinoma, Renal Cell / Q000453:epidemiology*; D016208:Databases, Factual; D006801:Humans; D007680:Kidney Neoplasms / Q000453:epidemiology*; D008297:Male; D018426:SEER Program; D017678:Sex Distribution; D055815:Young Adult
keywords: anatomy and histology; carcinoma, renal cell; female; kidney; tumorigenesis