Table 3: Site-specific head and neck cancer stratified by HPV E6/E7, tobacco, and alcohol status.1

Cases Controls Oral cavity versus controls Oropharynx versus controls Oral cavity Oropharynx  OR (95% CI)  OR (95% CI) HPV E6/E72 Risk factor (%) (%) (%)  Tobacco3  Negative   Never 54 (32.0) 2 (2.7) 150 (35.3) 1.0 1.0   ≤30 41 (24.3) 6 (8.2) 127 (29.9) 0.9 (0.6–1.5) 3.2 (0.6–16.6)   >30 58 (34.3) 19 (26.0) 119 (28.0) 1.4 (0.8–2.3) 11.0 (2.4–51.7)   test for trend value 0.19 <0.0001  Positive   Never 3 (1.8) 8 (11.0) 10 (2.4) 1.0 1.0   ≤30 3 (1.8) 19 (26.0) 15 (3.5) 0.3 (0.03–2.4) 1.4 (0.4–4.9)   >30 10 (5.9) 19 (26.0) 4 (0.9) 3.5 (0.5–26.9) 4.7 (1.03–21.7)   test for trend value 0.008 0.01  Alcohol4  Negative   Never 57 (33.7) 2 (2.7) 170 (39.9) 1.0 1.0   ≤21 54 (32.0) 10 (13.7) 166 (39.0) 1.1 (0.7–1.8) 5.4 (1.1–25.7)   >21 42 (24.8) 15 (20.6) 59 (13.9) 3.1 (1.7–5.5) 24.3 (4.9–121.3) test for trend value 0.009 <0.0001  Positive   Never 3 (1.8) 6 (8.2) 14 (3.3) 1.0 1.0   ≤21 5 (3.0) 27 (37.0) 15 (3.5) 1.2 (0.2–7.3) 4.1 (1.2–14.7)   >21 8 (4.7) 13 (17.8) 2 (0.5) 9.8 (0.9–106.9) 8.5 (1.2–60.2)   test for trend value 0.002 0.001 Tobacco/alcohol5  Negative   Never/never 40 (23.8) 1 (1.4) 93 (22.0) 1.0 1.0   ≤30/≤21 21 (12.5) 1 (1.4) 63 (14.9) 1.0 (0.5–1.9) 1.9 (0.1–31.1)   ≤30/>21 10 (6.0) 4 (5.5) 24 (5.7) 1.5 (0.6–3.6) 22.8 (2.2-235.2)   >30/≤21 20 (11.9) 8 (11.0) 53 (12.5) 1.2 (0.6–2.3) 18.7 (2.2–160.8)   >30/>21 31 (18.4) 11 (15.1) 29 (6.7) 4.0 (2.0–8.3) 56.3 (6.2–512.7)   test for trend value 0.07 <0.0001  Positive   Never/never 2 (1.2) 2 (2.7) 7 (1.7) 1.0 1.0   ≤30/≤21 2 (1.2) 13 (17.8) 9 (2.1) 0.7 (0.04–12.0) 8.9 (0.96–82.9)7   ≤30/>21 0 (0.0) 4 (5.5) 2 (0.5) 0.6 (0.02–17.2) 6 13.7 (0.8–227.9)   >30/≤21 2 (1.2) 9 (12.3) 2 (0.5) 2.6 (0.1–67.4) 29.3 (2.1–408.7)7   >30/>21 8 (4.8) 8 (11.0) 0 (0.0) 55.0 (0.8–3651.0)6,7 18.3 (0.5–627.2)6,7   test for trend -value 0.008 0.001

1Percentages based on available data; 2HPV E6/E7 seronegative for HPV-16, -18, and/or -33; HPV E6/E7 seropositive for HPV-16, -18, and/or -33; 3adjusted for age (continuous), gender, and average drinks/week (continuous); 4adjusted for age (continuous), gender, and tobacco pack-years (continuous); 5adjusted for age (continuous) and gender, all never groups combined with never/never as reference group; 6Logit estimator, 0.5 is added to zero cells; 7CMH -value < 0.049.