The Value Of CT Spectral And Perfusion Imaging In Evaluating The Lymphovascular And Perineural Invasion Of Gastric Cancer

Objective:The purpose of this study was to investigate spectral computed tomography（CT）and CT perfusion imaging in the preoperative evaluation of lymphovascular invasion（LVI）and perineural invasion（PNI）in gastric cancer（GC）.In the first part,we investigate the utility of combining spectral CT and clinical parameters in the evaluation of LVI/PNI in GC.In the second part,we investigate the utility of combining spectral CT and CT perfusion parameters in the evaluation of LVI/PNI in GC.Materials and methods:Firstly,we retrospectively analysed 121 patients with gastric adenocarcinoma from September 2020 to February 2022.All cases were confirmed by pathology and underwent spectral-CT examination.Patients were divided into positive（n=87）and negative（n=34）groups depending on LVI/PNI occurrence.Secondly,we prospectively analysed 87 patients with gastric adenocarcinoma from January 2022 to February 2023.All cases were confirmed by pathology and underwent"one-stop"spectral and perfusion CT imaging examination.Patients were divided into positive（n=65）and negative（n=22）groups depending on LVI/PNI occurrence.Clinical characteristics were collected,including demographic information,serum tumour markers,and gastroscopic pathological information.The effective atomic number（Zeff）,iodine concentration（IC）,and water concentration were measured in the arterial（AP）and venous（VP）phases.The blood flow（BF）,blood volume（BV）,mean transit time（MTT）,capillary permeability surface area product（PS）,and time to max（Tmax）were measured.Parameter differences between the two groups were compared,and diagnostic performance was evaluated.Results:1.In the first part,the LVI/PNI-positive group’s serum tumour marker CA125,histological grade,Borrmann type,Zeff,and IC were substantially greater than those of the negative group（all P（27）0.05）.The evaluated efficiency of the combination of clinical and spectral-CT parameters was superior to that of individual parameters.The clinical parameters combined with Zeff and IC in AP and VP exhibited good evaluation efficacy（AUC=0.890,F₁ score=0.888）.2.In the second part,the LVI/PNI-positive group’s Zeff,IC,BV,and MTT were substantially greater than those of the negative group（all P（27）0.05）.The evaluated efficiency of the combination of spectral-CT and CT-perfusion parameters was superior to that of individual parameters.The BV and MTT combined with Zeff and IC in AP and VP exhibited good evaluation efficacy（AUC=0.827;F₁=0.892）.The IC of the VP has a strong correlation with the BV.Conclusions:1.Clinical and energy spectral-CT parameters exhibited considerable value in the preoperative evaluation of LVI and PNI in GC.The combination of clinical and spectral-CT parameters exhibited a favorable performance in predicting LVI and PNI in GC.2.The"one-stop"spectral-perfusion CT imaging has good value in the preoperative evaluation of LVI/PNI in GC.The evaluated efficiency of the combination of spectral-CT and CT-perfusion parameters was superior to that of individual parameters.IC of VP and BV can be used as reference replacements for each other.