Application Of Intravoxel Incoherent Motion Diffusion-weighted Imaging In Diagnosing Different Types Of Lung Cancers

ObjectiveThe author explores the diagnostic value of intravoxel incoherent motion diffusion-weighted imaging（IVIM-DWI）in diagnosing different pathological types of lung cancer by analyzing the correlations between the serum tumor markers（TM）of lung cancer and these IVIM-derived quantitative parameters including Slow-ADC,Fast-ADC and f_fast.Materials and MethodsCT image is regarded as the basic inclusion criteria:（1）the diameter of lung lesion is no less than 2cm.（2）the proportion of calcification,hemorrhage or necrosis is no more tha-n half of the tumor.45 patients,who went to see a doctor in Shandong Provincial Qianfos-h an Hospital from October 2014 to June 2015,were scanned by GE discovery 750 MR with an eight channel body coil before clinical treatment to get routine and multi-b value（b=0,10,30,50,80,100,150,200,300,400,600,800,1000,1200,1500s/mm²）DWI sequence.All patients were proved with lung cancer by pathological examination,including 27 cases N-SCLC（13 cases squamous carcinoma,14 cases adenocarcinoma）and 18 cases SCLC.These patients were trained to breathe before examination,maintaining the supine and feet-first position with their hands up around head.The patients were scanned from the lung tip to the bottom.Slow-ADC,fast-ADC and f_fast were measured on an AW4.5 workstation by using Function-MADC analysis software.The common tumor makers of lung cancer include carcinoembryonic antigen（CEA）,neuron specific enolase（NSE）,pro-gastrin releasing peptide precursor（ProGRP）and cyto-keratin 19 fragment antigen 21-1（CYFRA21-1）and squamous cell carcinoma antigen（SCC-Ag）.The level of these serum TM were noted,including 12 cases adenocarcinoma,11 cases squamous carcinoma and 13 cases SCLC.The author used SPSS13.0 statistical analysis software for data processing.The values of slow-ADC,fast-ADC and f_fast were analyzed between the different pathological types of lung cancers by using the independent sample t test or the Mann-Whitney U test.The diagnostic efficiency of these parameters were evaluated by receiver operator characteristic curve（ROC）.The correlations between these IVIM-DWI parameters and the serum tumor markers of lung cancer were analyzed by using Spearman rank correlation.ResultsThe slow-ADC average of NSCLC group(0.90×10^-3mm²/s)is higher than the average of SCLC group(0.69×10^-3mm²/s)and there are significant differences in slow-ADC values between the two groups（t=3.849,P=0.00）.There are significant differences in slow-ADC values between SCLC group and the adenocarcinoma group（t=3.226,P=0.03）,the squam ous carcinoma group（t=3.658,P=0.01）.There is no significant difference in fast-ADC as well as f_fastast value between any two groups.The slow-ADC value’s area under the ROC is0.874（AUC=0.874）.The correlation coefficient（r=-0.730,P=0.011）indicates that there exists negative correlation between SCC-Ag of squamous carcinoma group and slow-ADC.ConclusionThe slow-ADC of IVIM-DWI parameters is useful in differentiating the NSCLC and SCLC and has a certain meaning in diagnosing different pathological types of lung cancers.