The incidence of testicular germ cell carcinoma (TGCC), the most common malignancy among men aged 20-34, has increased several-fold during the past several decades. The etiology of TGCC is poorly understood and the cause of the increased incidence is unknown. Established risk factors include age, race, personal history of undescended testes, and family history of TGCC, none of which is modifiable.

Alcohol is an established testicular toxicant, causing testicular atrophy, gynecomastia, and disrupted sexual function in alcoholic men. In both alcoholics and non-alcoholic men with moderate intake, alcohol depresses levels of circulating testosterone and luteinizing hormone. We hypothesized that alcohol consumption, particularly during adolescence, increases the risk of TGCC. A single previous epidemiologic analysis of alcohol intake and TGCC found no association.

We conducted a population-based case-control study among 18-44 year-old male residents of three Washington State counties. Cases (n=400) were diagnosed during 1999-2006 with a first, primary TGCC. Controls (n=1,020) were men of similar age with no history of TGCC from the same population identified through random-digit telephone dialing. Questionnaires elicited information on demographic, medical, and lifestyle factors, including usual consumption of beer, wine, and liquor during the 5 years prior to reference date and during grades 7-12. We used logistic regression models to compute odds ratio (OR) estimates and 95% confidence intervals (CI) for TGCC in men that consumed 1-6, 7-13, and 14+ alcoholic beverages per week compared to those that consumed none, adjusting for age, education, smoking, and current marijuana use.

A higher proportion of cases than controls (73% vs. 66%) reported drinking 1 or more alcoholic beverages per week during the five years prior to reference date, and during grades 9-12 (44% vs. 37%). Consumption of 14+ alcoholic drinks/week was associated with an approximately 60% increased risk of TGCC (OR=1.62; 95% CI: 1.02-2.58) for consumption during the 5 years prior to reference date, and for consumption during grades 9-12 (OR=1.56; 95% CI: 0.99-2.47). The risk of TGCC appeared to be similar for consumption of beer, wine, or liquor, and for consumption of alcoholic beverages during adolescence versus consumption during adulthood. The risk of TGCC associated with 14+ alcoholic drinks/week was higher among men diagnosed with nonseminomas (OR=2.28; 95% CI: 1.08-4.82) than among men diagnosed with seminomas (OR=1.40 95%CI: 0.80-2.42).

Our results indicate that consumption of 14 or more alcoholic beverages per week during adolescence or adulthood may be associated with a doubling of the risk of non-seminomatous TGCC. This is the first study to report an association between alcohol consumption and an increased risk of TGCC. Additional studies are needed to clarify the relationship between alcohol intake and TGCC.

Citation Information: Cancer Prev Res 2008;1(7 Suppl):B127.

Seventh AACR International Conference on Frontiers in Cancer Prevention Research-- Nov 16-19, 2008; Washington, DC