Head and neck cancer associated with herpes simplex virus 1 and 2 and other risk factors

We investigated whether herpes simplex viruses, HSV-1 and HSV-2, are cofactors of head and neck cancer (HNC) in association with tobacco, alcohol, or HPV-16 infection. The study included 164 HNC cases and 295 controls. Serologic tests were used to distinguish HSV-1 and HSV-2. Antibodies to anti-VLP HPV-16 and HPV-16 E6 and E7 were evaluated by ELISA. After adjusting for age, tobacco, alcohol use, and number of sexual partners, risk of cancer was not significantly increased in those with HSV-1 [adjusted odds ratio (OR) = 0.7] or HSV-2 (OR = 0.8) compared to HSV-negative patients. Although heavy use of tobacco, alcohol and HPV-16 infection was associated with an increased risk of HNC, the adjusted risk among those infected with HSV-1 or HSV-2 lowered the odds compared to those who were not infected. Heavy smokers (OR = 1.7) and heavy drinkers infected with HSV-1 (OR = 4.2) or HSV-2 (smokers: OR = 1.6; drinkers: OR = 3.2) had lower odds compared to seronegative HSV-1 heavy users (smokers: OR = 2.5; drinkers: OR = 5.5) or HSV-2 (smokers: OR = 1.9; drinkers: OR = 6.2). Those seropositive to HPV-16 E6 and/or E7 but not HSV-1 (OR = 27.4) or HSV-2 (OR = 18.0) had higher risk of HNC compared to those infected with HSV-1 (OR = 16.7) or HSV-2 (not estimable). These findings suggest that seropositivity to HSV-1 and HSV-2, although not independent risk factors for HNC, may modify the risk of HNC associated with exposure to tobacco, alcohol, or HPV-HR. (c) 2005 Elsevier Ltd. All rights reserved.