Table 4.

The Influence of the Analyzed Parameters on the 2-, 5- and 10-Year Cancer-Specific Survival (CSS)

Parameter	Groups	2-Year CSS (%)	5-Year CSS (%)	10-Year CSS (%)	χ2 Test-Value	p-value
Age	19–49	82	75	75	3.037	0.386
	50–61	89	81	20
	62–70	84	73	22
	71–88	73	40	40
Gender	Female	80	64	35	0.956	0.339
	Male	84	73	52
WHO	0	94	86	86	19.412	<0.001
	1	80	68	27
	2	50	11	0
	3	0	0	0
Location	Parotid	83	62	36	1.068	0.285
	Submandibular	81	75	50
Clinical nerve palsy	Yes	61	47	38	2.292	0.021
	No	89	75	41
Radicality	R0	84	69	43	1.444	0.485
	R1	79	69	43
	R2	90	72	36
Nerve palsy after surgery	Yes	66	46	33	2.740	0.006
	No	88	77	42
Histopathological type	Squamous	64	55	0	6.758	0.239
	Adenocarcinoma	94	69	37
	Cystic adenoid carcinoma	82	74	37
	Undifferentiated	80	60	30
	Acinic	100	87	65
	Other	83	72	72
Neuroinvasion	Yes	73	54	36	2.050	0.040
	No	86	75	45
Angioinvasion	Yes	68	50	50	1.390	0.164
	No	85	71	43
Stage	I	100	100	80	16.118	0.001
	II	92	79	48
	III	74	74	38
	IVab	74	43	37
T	1	100	100	80	22.324	<0.001
	2	91	78	49
	3	76	66	34
	4	62	33	33
N	Positive	67	43	23	3.511	<0.001
	Negative	89	79	51
Time	<9 weeks	85	73	54	1.444	0.146
	≥9 weeks	79	61	28
Technique of RT	2D	53	25	25	3.718	0.004
	3D	81	73	50
	IMRT	90	76	36
Dose	<60Gy	50	37	13	11.013	<0.001
	≥60Gy	89	75	49
CHT	Yes	82	68	34	0.489	0.625
	No	82	68	42
Hemoglobin level	<12.5 mg/dL	64	64	N/A	1.016	0.310
	≥12.5 mg/dL	86	75	N/A
Tumor volume	≤ 10 cm3	100	100	80	9.572	0.022
	10.1–50 cm3	92	73	N/A
	50.1–100 cm3	85	64	24
	>100 cm3	64	51	N/A
Irradiation area	Only surgical bed with margin	91	77	66	17.747	<0.001
	Surgical bed + lnd. group I–II	92	74	N/A
	Surgical bed + unilateral lnd.	86	78	39
	Surgical bed + bilateral lnd	56	30	10
Tumor bed volume (dose ≥ 60Gy)	≤ 100 cm3	100	100	80	6.581	0.086
	100.1–200 cm3	90	72	43
	200.1–300 cm3	87	72	0
	>300 cm3	74	54	N/A
Elective area volume (dose ≥ 50Gy)	≤ 150 cm3	95	87	56	9.978	0.044
	150.1–300 cm3	82	66	0
	300.1–450 cm3	87	87	N/A
	450.1–600 cm3	83	44	N/A
	>600 cm3	66	33	N/A

Note: Statistically significant results in bold.

Abbreviations: p, significance level; R0, radical surgery; R1, non-radical microscopic surgery; R2, non-radical macroscopic surgery; RT, radiotherapy; CHT, chemotherapy; RT, radiotherapy; 2D, two-dimensional planning; 3D, three-dimensional planning; IMRT, planning with intensity-modulated radiation therapy.