Table 1.

Description of the study population by case–control status and primary tumor site

LPSCC by Primary Site
Controls (N = 1,234)LPSCC (N = 631)PdifferencePharyngeal (N = 468)Laryngeal (N = 163)Pdifference
Age, mean y (σ)60.9 (11.1)59.5 (10.4)0.01a58.9 (10.4)61.1 (10.4)0.02c
Gender, n (%)
 Female333 (27.0%)132 (20.9%)0.01b91 (19.4%)41 (25.2%)0.15d
 Male901 (73.0%)499 (79.1%)377 (80.6%)122 (74.9%)
Race, n (%)
 White1114 (90.4%)572 (90.8%)0.80b427 (91.4%)145 (89.0%)0.35d
 Non-White119 (9.7%)58 (9.2%)40 (8.6%)18 (11.0%)
Cigarette smoking, n (%)
 Never-smoker497 (40.3%)144 (22.8%)<0.001b123 (26.3%)21 (12.9%)<0.001d
 I tertile (0.1–18.3 pack-years)282 (22.9%)143 (22.7%)118 (25.2%)25 (15.3%)
 II tertile (18.4–41.0 pack-years)254 (20.6%)161 (25.5%)114 (24.4%)47 (28.8%)
 III tertile (41.1–202.5 pack-years)201 (16.3%)183 (29.0%)113 (24.2%)70 (42.9%)
Alcohol consumption, n (%)
 Non-drinker151 (12.3%)51 (8.1%)<0.001b34 (7.3%)17 (10.4%)0.01d
 ≤14 drinks/wk787 (63.9%)282 (44.8%)226 (48.4%)56 (34.4%)
 >14 drinks/wk294 (23.9%)297 (47.1%)207 (44.3%)90 (55.2%)
BMI, n (%)
 Underweight (BMI < 18.5)17 (1.4%)29 (4.9%)<0.001b20 (4.5%)9 (6.0%)0.66d
 Normal (18.5 ≤ BMI < 25)337 (27.9%)276 (46.7%)210 (47.5%)66 (44.3%)
 Overweight (25 ≤ BMI < 30)468 (38.7%)207 (35.0%)156 (35.3%)51 (34.2%)
 Obese (BMI ≤ 30)387 (32.0%)79 (13.4%)56 (12.7%)23 (15.4%)
Highest level of education, n (%)
 High school or less340 (27.7%)249 (39.5%)<0.001b167 (35.7%)82 (50.6%)0.001d
 Beyond high school886 (72.3%)381 (60.5%)301 (64.3%)80 (49.4%)
HPV16 serology (L1), n (%)
 Negative993 (93.7%)336 (60.7%)<0.001b221 (53.3%)115 (82.7%)<0.001d
 Positive67 (6.3%)218 (39.4%)194 (46.8%)24 (17.3%)

Abbreviation: σ, SD.

  • at test for difference between cases (all LPSCC) and controls.

  • bFisher's exact test for difference between cases (all LPSCC) and controls.

  • ct test for difference across primary tumor sites (cases only).

  • dFisher's exact test for difference across primary tumor sites (cases only).