Table 1. Descriptive statistics of the main variables concerning patients and tumour parameters.

Characteristic	109 patients
Age at diagnosis
Median	63
Range	32–84
Follow-up period (months)
Median	13
Range	3–32
Pack-years of cigarette smoking
Median	29
Range	0–88
Sex, no. (%)
Male	88 (80.73%)
Female	21 (19.27%)
Site of origin, no. (%)	Subsite, no. (%)
Hypopharynx	9 (8.26%)	Post-cricoid region 3 (2.75%)
		Pyriform sinus 6 (5.5%)
Larynx	46 (42.2%)	Glottic 18 (16.51%)
		Supraglottic 15 (13.76%)
		Transglottic 12 (11.01%)
		Subglottic 1 (0.92%)
Oral cavity	33 (30.28%)	Cheek 3 (2.75%)
		Floor of mouth 8 (7.34%)
		Hard palate 4 (3.67%)
		Mobile tongue 15 (13.76%)
		Retromolar trigone 3 (2.75%)
Oropharynx	21 (19.27%)	Base of tongue 6 (5.5%)
		Posterior wall 1 (0.92%)
		Soft palate 1 (0.92%)
		Tonsil 13 (11.93%)
Primarytreatment, no. (%)
Surgical	61 (57.55%)
Radiochemotherapy	45 (42.45%)
AJCC stage, no. (%)
I	8 (7.34%)
II	21 (19.27%)
III	20 (18.35%)
IV	IVa 53 (48.62%), IVb 5 (4.59%), IVc 2 (1.83%)
cT classification, no.(%)
T1	12 (11.01%)
T2	32 (29.36%)
T3	22 (20.18%)
T4a	43 (39.45%)
cN classification, no.(%)
N0	61 (55.96%)
N1	10 (9.17%)
N2a	1 (0.92%)
N2b	18 (16.51%)
N2c	14 (12.84%)
N3	5 (4.59%)
Grading, no.(%)
G1	3 (2.75%)
G2	63 (57.8%)
G3	43 (39.45%)
HPV DNA, no.(%)
Negative	95 (87.16%)
High-risk HPV	12 (11.01%)
High and low risk	1 (0.92%)
Low risk	1 (0.92%)
High-risk HPV RNA, no.(%)
Negative	95 (87.16%)
HPV16	12 (11.01%)
HPV18	1 (0.92%)
HPV45	1 (0.92%)
P16 immunostaining
Positive	21 (24.77%)
Negative	88 (75.23%)

Abbreviations: AJCC=American Joint Committee on Cancer; cN=clinical N; cT=clinical T; HPV=human papillomavirus.