The value of dual-layer spectral CT in assessment of solid lung adenocarcinoma based on 2011 and 2020 pathological grading system / 中华放射学杂志

ABSTRACT

Objective:To explore the value of spectral CT in the preoperative evaluation of solid lung adenocarcinoma with different pathological grades based on the 2011 and 2020 version of the pathological grading system.Methods:A total of 76 cases of solid lung adenocarcinoma confirmed by surgery in Renji Hospital, School of Medicine, Shanghai Jiao Tong University, from January 2019 to September 2021 were analyzed retrospectively. All cases were divided into groups according to the grading system for invasive adenocarcinoma proposed by the International Association for the Study of Lung Cancer (IASLC) in 2011 and 2020 (G low group included G1 and G2 adenocarcinoma, G high group included G3 adenocarcinoma). The tumors with stage Ⅰ and Ⅱ were non-advanced and the tumors with stage Ⅲ and Ⅳ were advanced. The clinical manifestations (gender, age, smoking history and stage), routine CT parameters (tumor size, morphological characteristics, plain CT value and enhancement degree) and spectral parameters [iodine concentration, effective atomic number, enhanced monochromatic CT attenuation values of 40-200 keV (CT 40 keV-CT 200 keV), and the slope of spectral curve (k value)] were compared between G low group and G high group using independent sample t-test or Mann-Whitney U test. And the efficacy of each parameter for indicating G high adenocarcinoma was analyzed using receiver operating characteristic curve analysis and area under the curve (AUC), and the Z test was used to compare the AUC. Results:Seventy-six cases were included (59 cases of G low group and 17 cases of G high group in 2011 version; 46 cases of G low group and 30 cases of G high group in 2020 version). Among the 76 cases, 62 cases were non-advanced stage (50 cases of G low group and 12 cases of G high group in 2011 version; 37 cases of G low group and 25 cases of G high group in 2020 version) and 14 cases were advanced stage (9 cases of G low group and 5 cases in G high group in both 2011 and 2020 version). Among the non-advanced adenocarcinomas, the CT parameters of enhancement degree, k value and CT 40 keV-CT 60 keV in arterial phase and enhancement degree, k value and CT 40 keV-CT 70 keV in venous phase of G high group in 2011 grading system were significantly lower than those of G low group ( P<0.05), while other parameters were similar between G low and G high group in 2011 grading system ( P>0.05); and the CT parameters of CT 60 keV in arterial phase and CT 50 keV-CT 70 keV in venous phase of G high group in 2020 grading system were significantly lower than those of G low group ( P<0.05). Among the advanced adenocarcinomas, all of the clinical and CT parameters were similar between G low and G high group in both 2020 and 2011 grading systems ( P>0.05). For the non-advanced adenocarcinomas, there was medium to good efficacy of the CT parameters of enhancement degree, k value and CT 40 keV-CT 60 keV in arterial phase and enhancement degree, k value and CT 40 keV-CT 70 keV in venous phase for diagnosing 2011 grading system G high adenocarcinoma (AUC=0.700-0.853), with CT 50 keV in venous phase as the best; while the diagnosis efficacy of CT parameters of CT 60 keV in arterial phase and CT 50 keV-CT 70 keV in venous phase was poor for 2020 grading system G high adenocarcinoma (AUC=0.652-0.688), with CT 60 keV in venous phase as the best. After combining smoking history and CT 60 keV in venous phase, the diagnosis efficacy for 2020 grading system G high adenocarcinoma was slightly improved (AUC=0.772), but the difference had no significance ( Z=0.93, P=0.176). Conclusion:The spectral parameters are useful for distinguishing the pathological grades of solid lung adenocarcinoma. And the detecting efficacy for G high adenocarcinoma of IASLC 2011 version is slightly better than that of 2020 version.