title: Association between marijuana use and transitional cell carcinoma.
abstract: OBJECTIVE
  Marijuana smoking has been implicated as a causative factor in traditionally tobacco-related tumors of the head and neck and of the lung. When associated with marijuana use, such tumors occur in a much younger patient population than do similar tumors in tobacco smokers. Owing to the large number of young men with a history of marijuana presenting with transitional cell carcinoma to VA facilities, this study was designed to compare the marijuana use among young (aged less than 60 years) transitional cell carcinoma patients with that among age-matched controls.
  
  
  METHODS
  Fifty-two men aged less than 60 years presenting consecutively with transitional cell carcinoma and 104 age-matched controls (defined by having no history of transitional cell carcinoma, hematuria, or irritative voiding symptoms, as well as unremarkable results on urinalysis and urine cytology) completed questionnaires about exposure to various potential carcinogens, including radiation, Agent Orange, smoked or processed meats, dyes, tobacco, and marijuana.
  
  
  RESULTS
  Of the 52 transitional cell carcinoma patients, 46 (88.5%) reported a history of habitual marijuana usage, and 72 (69.2%) of the age-matched controls gave a history of habitual marijuana use. This difference was statistically significant (P = 0.008). In those with transitional cell carcinoma, marijuana use significantly correlated with tumor stage, grade, and number of recurrences.
  
  
  CONCLUSIONS
  Marijuana smoking might increase the risk of transitional cell carcinoma.
authors.affiliation: Department of Urology, Stanford University Medical Center, Stanford, California, USA.
authors.forename: Julie A
authors.initials: JA
authors.lastname: Chacko
authors.forename: Jared G
authors.initials: JG
authors.lastname: Heiner
authors.forename: Wendy
authors.initials: W
authors.lastname: Siu
authors.forename: Marie
authors.initials: M
authors.lastname: Macy
authors.forename: Martha K
authors.initials: MK
authors.lastname: Terris
mesh_terms: D002295:Carcinoma, Transitional Cell / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000009:adverse effects*; D008875:Middle Aged; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology / Q000209:etiology*