Table 1.

Demographic, treatment, and tumor-related characteristics of the study population

	At baseline (n = 177)	Dead (n = 53)	Missing (n = 29)	Final sample (n = 95)
Age (year)
Mean (SD)	59.5 (11.3)	62.1 (11.8)	54.1 (10.1)	59.6 (10.8)
Range	28–84	40–84	28–70	36–84
Gender (n)
Male	131	41	18	72
Female	46	12	11	23
Treatment (n)
None	4	2	–	2
Irradiation only	72	23	14	35
Surgery and irradiation	42	11	10	20
Surgery only	39	8	4	27
Chemotherapy only or combination with chemotherapy	20	9	1	11
Tumor (sub)sites (n)
Pharynx
Nasopharynx	10	4	1	5
Oropharynx	46	15	8	23
Hypopharynx	18	9	2	7
Larynx	42	10	7	25
Oral cavity	38	8	9	21
Other	23	7	2	14
Tumor stage (n)
T0	4	1	–	3
T1	32	3	2	27
T2	51	13	15	23
T3	37	12	5	20
T4	44	18	6	20
Tx	9	6	1	2
Nodal stage (n)
N0	90	20	15	55
N1	21	3	6	12
N2	49	21	5	23
N3	8	4	1	3
Nx	9	5	2	2
Distant metastasis (n)
M0	160	42	28	90
M1	6	5	–	1
Mx	11	6	1	4
AJCC/UICC tumor stage (n)
I	27	2	1	24
II	29	8	9	12
III	34	6	8	20
IV	80	33	10	37
Unknown	7	4	1	2
Prior malignancy (n)
No	162	45	28	89
Yes	15	8	1	6