Stem cell factor-mediated wild-type KIT receptor activation is critical for gastrointestinal stromal tumor cell growth

Table 1 Correlations between the co-expression of wild-type KIT receptor and stem cell factor and clinicopathological factors in gastrointestinal stromal tumors

	Co-expression of wild-type KIT receptor and stem cell factor
	Absent (n = 12)	Present (n = 39)	P value
Age (yr)	58.9 ± 13.2	52.8 ± 10.5	0.0524
Sex
Male	6	18	0.8154
Female	6	21
Tumor size (cm)	3.69 ± 1.68	6.21 ± 3.94	0.0118
Histological phenotype
Spindle type	8	26	0.7262
Epithelioid/mixed type	4	13
Cellularity
Sparse	1	6	0.8000
Moderate/dense	11	33
Tumor location
Gastric	6	25	0.5931
Non-gastric	6	14
Proliferative index	2.92 ± 2.23	7.21 ± 4.93	0.0012
pHH3
≤ 5	12	24	0.0282
> 5	0	15
Mitotic counts	3 ± 2.37	7.36 ± 6.36	0.0058
≤ 5	10	14	0.0004
> 5	2	25
Apoptosis index	44.58 ± 19.00	32.59 ± 17.63	0.0484
c-kit mutation
Presence	5	27	0.1659
Absence	7	12
National Institutes of Health risk group
Very low or low	10	10	0.0012
Intermediate or high	2	29