Multi-Parameters Derived from Dual-Layer Spectral-Detector CT in Evaluating the Pathological Tumor Staging of Rectal Adenocarcinoma / 中国医学影像学杂志

ABSTRACT

Purpose To explore the value of dual-layer spectral detector CT(DLSCT)in evaluating preoperative tumor staging in rectal adenocarcinoma(RA).Materials and Methods A total of 78 patients with pathologically confirmed RA in Guangdong Provincial Hospital of Chinese Medicine from May 2021 to March 2022 were involved in this retrospective study.All the patients underwent plain and dual-phase contrast-enhanced scans by DLSCT within one week before surgery.Taking pathological results as the golden standard,the accuracy rates of tumor staging were calculated and compared between the multiple-parameter maps derived from DLSCT and 120 kVp polyenergetic image.The effective atomic number(Z-eff)from plain scan,iodine concentration(IC)from arterial phase(AP)and venous phase(VP)were measured.The normalized iodine concentration(NIC)in AP and VP were calculated.The differences of Z-eff,NICAP and NICVP were compared among the pT1-2,pT3 and pT4 groups.The correlation between the pT stages and above values was assessed and the diagnostic efficiencies were analyzed.Results The overall accuracy rate(88.46%vs.67.95%;χ2=9.628,P=0.002),the pT1-2 staging accuracy rate(80.00%vs.40.00%;χ2=6.667,P=0.01),and the pT3 staging accuracy rate(88.10%vs.69.05%;χ2=4.525,P=0.033)of multiple-parameter maps derived from DLSCT were significantly higher than those of 120 kVp polyenergetic image,respectively.The Z-eff,NICAP and NICVP were significantly different among pT stage groups(F=6.456,11.029,12.698,all P<0.05)and exhibited a positive correlation with pT stages(r=0.371,0.367,0.363,all P<0.01).The areas under the curve of Z-eff,NICAP and NICVP to assess pT3-4 staging RA were 0.77,0.71 and 0.74,respectively.Conclusion The multiple-parameter maps derived from DLSCT can significantly improve the diagnostic accuracy of preoperative tumor staging of RA.Z-eff from plain scan and NIC from dual-phase helps differentiate pT1-2 from pT3-4 staging RA.