A Relationship Study Between Normalized Iodine Concentration Of Dual Source CT Dual Energy Imaging And Clinical TNM Staging Of Lung Cancer

Objective: Using the dual source CT dual energy imaging technology to analyze the relationship between normalized iodine concentration of lung cancer primary tumor and clinical TNM staging,and to provide broad space for improving the clinical diagnosis of TNM staging.Materials and methods:1.Between September 2013 and September 2015 in the First Affiliated Hospital of Guangxi Medical University,55 consecutive patients(33 men,22women;age range,31～71 years;mean age,56years)with 55 definite masses who were detected by Chest X-ray or plain CT scanning were chosen.The maximum diameters of the lesions are from 1.20 cm to 8.40 cm and the mean diameter is 4.32 cm.All the patients received the enhancement scanning of the second generation of Germany Siemens 64 storey dual-source CT scanner(Siemens Somatom definition definition flash)within ten days before surgery.And all the les ions were confirmed by pathologic examination after surgical resection.The clinical document(inc luding operating record,histological report,and situations of lymphatic involvement)is integrated.All patients were divided into two groups according to the pathologic reports: adenocarcinoma patients in40 cases and squamous cell carcinoma patients in 15 cases.2.The dual-energy enhanced scan image was transfered into dual-source CT Special Dual-Energy software to record lesions iodine content.All primary tumors iodine concentration were normalized by aorta.Normalized iodine concentration(NIC)formula: =primary tumor iodine concentration / the same layer of aortic iodine concentration.3.All the data were analyzed by SPSS l6.0 statistical software.The Compare Means between two groups were analyzed by two independent samples t-test,while the multigroup comparison were analyzed by variance analys is.The main factor influencing metastas is was estimated through logistic regression analys is(including primary tumor size,pathologic type and NIC).The ROC curve was created through NIC of primary tumor and the diagnostic threshold was obtained to identify Ⅰ-Ⅱstages and Ⅲ-Ⅳstages.Pearson test linear correlation anlalys is was used for the correlation of NIC and tumor size.Spearman correlation test was used for the correlation of NIC and clinical staging.P<0.05 statistically indicated a significant difference.Results:1.55 lung cancer cases were involved in the analys is.There were 40 cases of adenocarcinoma and 15 cases of squamous cell carcinoma.Lung cancer with metastasis and without metastasis were 28 cases and 27 cases respectively.The number of ≤3cm and >3cm group was 17 and 38 respectively.The patients were divided into 4 groups by clinical staging(24 cases in Ⅰstage,6 cases in Ⅱstage,19 cases in Ⅲstage and 6 cases in Ⅳstage).2.The primary tumor size of the adenocarcinoma group was less than the squamous cell carcinoma group.The adenocarcinoma group had higher value of NIC than the squamous cell carcinoma group.But they were not statistically significant(P>0.05).3.The lung cancer of >3cm group had higher value of NIC than those in≤3cm group.No significant difference of NIC was found in the two groups(P>0.05).4.The primary tumor size of lung cancer with metastasis was greater than those without metastasis(P>0.05).Tumors with metastasis had higher value of NIC than those without metastasis(P<0.05).5.The relationship between NIC of primary tumor and metastasis was estimated by logistic regression analysis to check confouding factors.NIC of primary tumor was relavant to metastasis(P<0.05)but not primary tumor size and pathologic type(P>0.05)in integral analys is.In sratification analysis,it was found that NIC was the factor influencing metastasis(P<0.05)but not primary tumor size(P>0.05)for adenocarcinoma.Both of the NIC and primary tumor size were not the facors influenc ing metastas is(P>0.05)for squamous cell carcinoma.6.The study of 55 patients showed that the NIC of primary tumor increased gradually with the increasing staging.There was significant difference among the groups(P<0.05).7.The diagnostic threshold of primary tumor NIC was 0.296,which was an indicator to judgeⅠ-Ⅱstages and Ⅲ-Ⅳstages(≤0.296 for Ⅰ-Ⅱstages,>0.296 for Ⅲ-Ⅳstages).The diagnostc sensitivity,specificity and coincidence rate was 96.0%,75.9% and 85.2% respectively.8.The study of 55 patients indicated that the NIC of lung cancer had no significant correlation to primary tumor size(r=0.106,P>0.05)while it had positive correlation to clinical staging(r=0.681,P<0.05).Conclusion:1.Between lung cancer with metastasis and without metastasis,adenocarcinoma and squamous cell carcinoma,the primary tumor size differences were not statistically significant(P>0.05).The tumor size had limited differential diagnosis value.2.Between adenocarcinoma and squamous cell carcinoma,lung cancer of≤3cm group and >3cm group,the primary tumor NIC differences were not statistically significant(P>0.05).The NIC of lung cancer had no significant correlation to primary tumor size(P>0.05).The NIC of lung cancer with metastasis had higher value than those without metastasis(P<0.05).3.NIC of primary tumor was relavant to metastasis(P<0.05)in integral analys is.In sratification analysis,it was found that NIC was the factor influencing metastasis(P < 0.05)but not primary tumor size(P > 0.05)for adenocarcinoma.Both of the NIC and primary tumor size were not the facors influencing metastasis(P>0.05)for squamous cell carcinoma.4.The NIC of primary tumor increased gradually with the increas ing staging.There was significant difference among the groups(P<0.05).The NIC of lung cancer had positive correlation to clinical staging(P<0.05).5.When primary tumor NIC>0.296 through the analys is of ROC curve,it was strongly suggested the posibility of Ⅲ-Ⅳstages in lung cancer.We recommened NIC>0.296 as quantitative indicator to suggest anvanced lung cancer.