title: Population-based case-control study of recreational drug use and testis cancer risk confirms an association between marijuana use and nonseminoma risk.
abstract: BACKGROUND
  Testicular germ cell tumor (TGCT) incidence increased steadily in recent decades, but causes remain elusive. Germ cell function may be influenced by cannabinoids, and 2 prior epidemiologic studies reported that the use of marijuana may be associated with nonseminomatous TGCT. Here, the authors evaluate the relation between TGCTs and exposure to marijuana and other recreational drugs using a population-based case-control study.
  
  
  METHODS
  In total, 163 patients who were diagnosed with TGCT in Los Angeles County from December 1986 to April 1991 were enrolled, and 292 controls were matched on age, race/ethnicity, and neighborhood. Participants were asked about drug use by a structured, in-person interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression analysis adjusted for history of cryptorchidism; education; religiosity; and reported use of marijuana, cocaine, and amyl nitrite.
  
  
  RESULTS
  Compared with never use, ever use of marijuana had a 2-fold increased risk (OR, 1.94; 95% CI, 1.02-3.68), whereas ever use of cocaine had a negative association with TGCT (OR, 0.54; 95% CI, 0.32-0.91). Stratification on tumor histology revealed a specific association of marijuana use with nonseminoma and mixed histology tumors (OR, 2.42; 95% CI, 1.08-5.42).
  
  
  CONCLUSIONS
  A specific association was observed between marijuana use and the risk of nonseminoma and mixed tumors. To the authors' knowledge, this is the first report of a negative association between cocaine use and TGCT risk. The current results warrant mechanistic studies of marijuana's effect on the endocannabinoid system and TGCT risk and caution that recreational and therapeutic use of cannabinoids by young men may confer malignant potential to testicular germ cells.
authors.affiliation: Department of Preventive Medicine, University of Southern California, Los Angeles, CA 90089-9175, USA.
authors.forename: John Charles A
authors.initials: JC
authors.lastname: Lacson
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Carroll
authors.forename: Ellenie
authors.initials: E
authors.lastname: Tuazon
authors.forename: Esteban J
authors.initials: EJ
authors.lastname: Castelao
authors.forename: Leslie
authors.initials: L
authors.lastname: Bernstein
authors.forename: Victoria K
authors.initials: VK
authors.lastname: Cortessis
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000009:adverse effects*; D009373:Neoplasms, Germ Cell and Embryonal / Q000453:epidemiology*; D012307:Risk Factors; D013736:Testicular Neoplasms / Q000453:epidemiology; D055815:Young Adult