Clinical Study Of 1.5T Magnetic Resonance Apparent Diffusion Coefficient For Monitoring The Early Outcome Of Lung Adenocarcinoma On Molecular Targeted Therapy

Objective:To explore the value of apparent diffusion coefficient (ADC) as an early response monitor in lung adenocarcinoma with targeted therapy in 1.5T Magnetic Resonance.Materials and methods:32 patients pathologically diagnosed as lung cancer were included in this study, before and seven days after treatment by MRI and DWI sequence can scan,30 days after the treatment with routine MRI scans.CT scan was performed before and seven days after treatment. According to MASS Version (Morphology, Attenuation, Size and Structure criteria), The response of lung cancers to therapy were classified into two groups:24cases in responding group,8 cases in non-responding group. The experimental data were Normal test. ADC values between the two way was matching t test betwen before and seven days after treatment. Maximum diameter, Tumors shrink rate> ADC values and the difference of the average ADC value were performed by two independent sample t-test between effective and ineffective group. The difference of the average ADC value at seventh days after therapy were analyzed by independent sample t test. The percentage of ADC value at seventh days after therapy were analyzed with ROC curve, then select the optimal value and confirm the diagnostic threshold.Results:1、In 32 cases of middle-late stage lung adenocarcinoma cases, by comparing the two groups before treatment, treatment after 7 days tumors had the largest diameter and tumors had the shrinking rate. The seventh day of lung cancer before and after treatment, two groups was not obvious change in morphology, there was no statistically significant difference between the two groups (t=-0.358,-0.560, P= 0.723,0.579>0.05).Two groups of tumors had the average maximum diameter of the shrinking rate change is not obvious, there was no statistically significant difference between the two groups (t=-0.832, P=0.413>0.05)2、Effective group 7 days after treatment, the average ADC values of lung lesions than before treatment significantly increased (t=-8.21, P=0.00<0.05), and the ADC values of invalid group is not obvious change (t=-1.87, P=0.104>0.05). Before the treatment, the average ADC values of lung lesions had obvious difference between two groups (t=-1.382, P=0.177>0.05). And 7 days after treatment, there are obvious differences between the two groups (t=5.69, P=0.00<0.05)3、Effective group and ineffective group seventh days after treatment, Effective group ADC value was elevated to the level is invalid group was more, Two there is statistical significance (t=7.55, P=0.00<0.05)4、The seventh day average lesion ADC important index of degree of change can be used as targeted therapy in lung adenocarcinoma with curative effect evaluation of whether the value of lung adenocarcinoma after chemotherapy.This study obtained by ADC is worth the elevated level of not less thanl% as the efficacy of lung cancer by targeted therapy evaluation standard, area under the curve is 0.922, early diagnosis of lung adenocarcinoma targeted therapy is effective sensitivity 83.3%, specificity87.5%Conclusion:The early changes of lung adenocarcinoma after molecular targeted therapeutic can be reflected by the change of ADC value of lung adenocarcinoma, and the change of ADC value of lung adenocarcinoma by targeted therapy is more sensitive than the change of the length of the lesions. Therefore, the lung adenocarcinoma early changes in ADC value can be used as a monitoring index of lung adenocarcinoma by targeted therapy. The change rate of ADC in early stage of lung adenocarcinoma by targeted therapy can predict the early curative effect of targeted therapy.