Table 1.

Characteristics of squamous cell carcinoma of the head and neck (SCCHN) cases and cancer-free controls in a North American population.

Variables	Cases (n = 703)		Controls (n = 685)		P a
	n	%	n	%
Age (years)					0.745
<57	352	50.1	337	49.2
≥ 57	351	49.9	348	50.8
Sex					0.882
Female	170	24.2	168	24.5
Male	533	75.8	517	75.5
Race
Caucasians	647	92.0	647	94.5	0.066
Others	56	8.0	38	5.5
Asian	5	0.7	1	0.1
Black	30	4.3	16	2.3
Hispanic	19	2.7	21	3.1
American Indian	2	0.3	0	0.0
Smoking statusb					< 0.001
Never	250	35.6	363	53.2
Former	223	31.8	255	37.3
Current	229	32.6	65	9.5
Ever	452	64.4	320	46.9
Alcohol useb					<0.0001
Never	187	26.6	294	43.1
Former	181	25.8	137	20.1
Current	334	47.6	252	36.9
Ever	515	73.4	389	57.0
Tumor siteb
Oropharynx	367	52.3
Non-oropharynxc	335	47.7
T staged
T1	201	28.7
T2	260	37.0
T3	123	17.5
T4	118	16.8
N staged
N0	232	33.0
N1	77	11.0
N2	381	54.3
N3	12	1.7
Overall staged
I	97	13.8
II	72	10.3
III	101	14.4
IV	432	61.5

^aTwo-sided χ² test.

^bMissed 1 patients’ and 2 controls’ information.

^cIncluded oral cavity (n=214), hypopharyngeal (n=20) and larynx (n=101) cancer cases.