Table 4.

Correlation of KIT genetic aberrations to CD117 expression

SubtypeKIT mutationGene copy numberGenetic aberrationa
MutationWTIncreasedNormalAberratedNon
IHC scoresb
0302731528843260
1161291313228177
2524524920
3322421619
Positive/total24/54175/44822/37177/46543/86156/416
Positive rate (%)44.439.159.538.15037.5
Pc0.55d0.02e0.04f

Abbreviations: WT, wild type.

aGenetic aberration includes KIT mutation and increased gene copy number. Five cases show both genetic mutation and increased gene copy number of KIT.

bThe signal intensity of immunohistochemistry results were determined by 3 individual pathologists and scored as 0, 1, 2, and 3 with score “0” as negative and score “3” as the strongest.

cSignificance evaluated by chi-square tests.

dPositive rate of CD117 in cases with KIT mutation versus that in cases without KIT mutation.

ePositive rate of CD117 in cases with increased KIT gene copy number versus that in cases with normal KIT gene copy number.

fPositive rate of CD117 in cases with KIT genetic aberrations versus that in cases without KIT aberrations.