title: Sorting the hype from the facts in testicular cancer: is testicular cancer related to trauma?
abstract: OBJECTIVE
  The rate of testicular cancer is increasing. Trauma severe enough to cause testicular atrophy is a putative risk factor for testicular cancer but the epidemiological evidence is not conclusive. A population based, multicenter case-control study was performed from 1995 to 1997 to investigate potential risk factors for gonadal and extragonadal germ cell cancer.
  
  
  METHODS
  The study was done in 5 German regions. Interviews were performed with 269 eligible male patients with a histologically verified diagnosis and 797 controls. Detailed information on medical and family history was collected at personal interviews.
  
  
  RESULTS
  We identified a significantly elevated risk for testicular cancer in relation to testis and/or groin trauma (odds ratio 2.5, 95% confidence interval [CI] 1.51 to 4.20). After introducing a lag time by excluding reports of trauma within the last 12 months before diagnosis or interview the corresponding odds ratio was 2.1 (95% CI 1.24 to 3.61). Analysis of the circumstances and the reported types of injury allowed us to restrict the study to testis trauma specifically, which had an odds ratio of 3.49 (95% CI 1.78 to 6.81). To account for a potential reporting bias analysis was restricted to traumatic episodes for which medical attention was sought. This restriction resulted in an odds ratio of 0.70 (95% CI 0.19 to 2.63) after excluding from study trauma reports within the last 12 months.
  
  
  CONCLUSIONS
  The results of our study do not support the hypothesis that testicular trauma is an important risk factor for testicular cancer. The possibility of recall bias should be considered.
authors.affiliation: Bremen Institute for Prevention Research and Social Medicine, Bremen, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Merzenich
authors.forename: W
authors.initials: W
authors.lastname: Ahrens
authors.forename: A
authors.initials: A
authors.lastname: Stang
authors.forename: C
authors.initials: C
authors.lastname: Baumgardt-Elms
authors.forename: I
authors.initials: I
authors.lastname: Jahn
authors.forename: C
authors.initials: C
authors.lastname: Stegmaier
authors.forename: K H
authors.initials: KH
authors.lastname: Jöckel
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D018237:Germinoma / Q000209:etiology*; D006119:Groin / Q000293:injuries*; D006801:Humans; D008297:Male; D017169:Neoplasms, Post-Traumatic; D016017:Odds Ratio; D012307:Risk Factors; D013736:Testicular Neoplasms / Q000209:etiology*; D013737:Testis / Q000293:injuries*