A preliminary study of spectral CT parameters in gastrointestinal stromal tumor risk classification / 实用放射学杂志

ABSTRACT

Objective To evaluate the value of spectral CT in risk classification of gastrointestinal stromal tumor (GIST).Methods Forty-one patients with GIST were collected,including 1 3 in high risk,1 2 in medium risk,1 1 in low risk and 5 in very low risk. All of the patients underwent plain and triple phases contrast enhanced CT with spectral CT scanning mode.CT value of 70 keV monochromatic images,the slope of spectral curve and normalized iodine concentration (NIC)were measured and calculated.Then, data was correlated with the risk of GIST.Results ①The CT value of 70 keV monochromatic images was negative correlation in the arterial phase (r=-0.173),positive correlation in delayed phase (r=0.552),and no correlation in venous phase with the risk of GIST.②The slopes of spectral curves in delayed phase were significantly different in GISTs with the different risk (χ2= 6.641,P= 0.036).③The NIC values of GISTs with different risk were significantly different in the triple phases (F=3.646,χ2=6.046,F=57.233,P=0.035, P=0.049,P<0.001),and correlated with the risk of GIST (r=-0.564)in the delayed phase.Conclusion Quantitative paremeters of spectral CT imaging such as the CT value of 70 keV,the slopes of spectral curves and iodine concentration are valuable for the risk classification of GIST,and can be used as a preoperative reference.