Aapplication value of spectral CT in the evaluation of the differentiation degree of colorectal cancer

ObjectiveTo investigate the application value of each parameter of 256-row Revolution spectral CT in evaluating the differentiation degree of colorectal cancer.

MethodsFifty patients with colorectal cancer diagnosed by colonoscopy or pathology were selected, and detected using the GSI spectral CT plain scan and dual-phase scan before surgery.The relevant spectral images were obtained through GSI Viewer software, the appropriate region of interest was delineated in the lesion, and the iodine base value(IC), water concentration, effective atomic number(Eff-Z), normalized iodine concentration(NIC) and energy spectral slope(K) of the lesion were measured.According to the pathological results, 50 patients were divided into the low differentiation group and middle-high differentiation group.The spectral parameters were compared between two groups, and the diagnostic ability of each spectral parameter were analyzed using the receiver operating characteristic curve.

ResultsAmong 50 patients, 32 cases in middle-high differentiation group and 18 cases in low differentiation group were identified.The lymph node metastasis in low differentiation group was higher than that in middle-high differentiation group(P < 0.05).There was no statistical significance in the IC, NIC, water concentration, Eff-Z and K of arterial phase, and water concentration and Eff-Z of venous phase between two groups(P>0.05).The IC, NIC and K of venous phase in low differentiation group were higher than those in middle-high differentiation group(P < 0.05).The area under the curve, diagnostic threshold, sensitivity and specificity of venous phase IC, NIC, and K were (0.77, 0.81 and 0.79), (18.31, 0.56 and 2.07), (88.3%, 83.3% and 88.9%) and (62.5%, 75.0% and 68.7%), respectively.

ConclusionsThe parameters IC, NIC and K of spectral CT have high values in evaluating the differentiation of colorectal cancer.