Characteristic	No. of Patients	SPARC expression (stroma)		χ² test
Characteristic	No. of Patients	negative	positive	χ² test
Sex
Male	86	31	55	P = 0.832
Female	64	22	42	P = 0.832
Age (years)
<60	72	28	44	P = 0.381
≥60	78	25	53	P = 0.381
Tumor position
head and neck	111	40	71	P = 0.761
body and tail	39	13	26	P = 0.761
Differentiation
Well	5	5	0	P = 0.008*
Moderately	96	33	63
Poorly	49	15	34
TNM stage
I + II	89	32	57	P = 0.847
III + IV	61	21	40	P = 0.847
perineural invasion
Absent	38	15	23	P = 0.537
Present	112	38	74	P = 0.537
Vascular invasion
Absent	133	52	81	P = 0.006*
Present	17	1	16	P = 0.006*
LN metastasis
Absent	90	32	58	P = 0.994
Present	60	21	39	P = 0.994