Clinical Study Of Energy-spectrum CT To Evaluate The Efficacy Of Microwave Ablation For Lung Cancer

Objective:Energy-spectrum CT scans were performed on lung cancer patients treated with microwave ablation（MWA）before and at one month,three months,and six months after surgery to obtain post-processing data such as three-stage enhanced base matter concentrations and energy-spectrum curves to assess the efficacy and prognosis of microwave ablation of lung cancer,to explore the clinical value of energy-spectrum CT for evaluating the effectiveness of microwave ablation of lung cancer after surgery,and to promote and guide the selection of clinical treatment strategies.Methods:Case histories of 47 lung cancer patients who underwent CT-guided microwave ablation of lung cancer in our hospital between October 2020 and June 2022 and were confirmed by pathology were collected.All patients underwent energy-spectral CT enhancement scans within three days before MWA.After one month,three months,and six months after MWA treatment,images of arterial,venous,and delayed phases were obtained.Data were obtained from iodine base material images,single energy images at70 ke V levels,and energy spectral curves.The iodine content（IC）and the normalized iodine content（NIC）were calculated.Efficacy was assessed at six months after MWA according to the m RECIST criteria:complete response（CR）,partial response（PR）,stable disease（SD）,progressive disease（PD）,and was divided into The effective group（CR+PR）,and the invalid group（SD+PD）were statistically and analytically analyzed for energy spectrum parameters to assess the efficacy of MWA for lung cancer.Results:At one month after MWA treatment in 47 patients,the target lesions were significantly larger than before MWA[（23.57±10.54）mm vs.（27.49±14.08）mm,P<0.05];The mean tumor length diameter decreased at three months after MWA compared to one month after MWA[（19.57±11.36）mm,P<0.05)],and the target lesion was significantly smaller at six months after MWA（15.70±10.49）mm,which was statistically different from both before and one month after MWA;The comparison between groups suggested that the tumor length diameter in the effective group was significantly smaller than that in the ineffective group（all P<0.05）.The differences in IC_APand NIC_APpatients in the effective group were statistically significant when compared between pre-MWA,one month after MWA,three months after MWA,and six months after MWA.The IC_APat six months after MWA was significantly smaller than before MWA,and NIC_APat one month and six months after MWA compared with that before MWA.The difference was statistically significant（P<0.05）.The triphasic enhanced IC and NIC values in the inactive group were also reduced compared with those before,but the differences were not statistically significant（all P>0.05）.The comparison between groups suggested that the P values of IC_APand NIC_APparameters between the effective and ineffective groups were<0.05 at six months after MWA treatment.The differences were statistically significant,and the efficacy assessment at this time demonstrated better sensitivity and clinical value.Conclusion:Energy-spectrum CT can quantitatively reflect the changes of blood supply to the lesions before and after microwave ablation treatment for lung cancer,and its assessment of IC and NIC values at six months after MWA using arterial phase is of clinical significance in assessing the efficacy of MWA treatment for lung cancer.