The Diagnostic Value Of Preoperative T Staging In Esophageal Carcinoma With High Field MRI

Background and purposeEsophageal cancer is the third most common gastrointestinal malignant tumor, its incidence and fatality rate were ranked the eighth and the sixth in the world. Onset age is above40years old,the male more than the female. The incidence of esophageal cancer shows clear regional variations. Now Esophageal cancer is mainly treated by surgical treatment,but a lot of patients had entered the middle and advanced stage when they were diagnosed,they had lost the opportunity to surgical treatment and only can take adjuvant therapy,which reduced the cure rate. Esophageal resection rate ranks from58%to92%. Patients’5-year survival rate is less than10%.when comprehensive treatment is used in early esophageal cancer, it can be as high as90%. Therefore, early detection, early diagnosis, early treatment for esophageal cancer has important for clinical. A variety of imaging modalities are used to investigate esophageal carcinoma, such as X-ray, computerized tomography (CT),Endoscopic Ultrasonography(EUS), magnetic resonance imaging(MRI), positron emission computed tomography(PET) et al. Because of heart and respiratory motion artifact, magnetic resonance imaging (MRI) is restricted with the application of esophageal cancer, but with the constant improvement of magnetic resonance imaging, and the continuous development of new functions technology, such as diffusion weighted imaging (DWI), magnetic resonance spectroscopy (MRS), etc.Magnetic resonance imaging (MRI) shows great superiority in the diagnosis、preoperative staging and postoperative evaluation of esophageal carcinoma. Diffusion-weighted magnetic resonance imaging (DWI) is the only technique in the state of non-invasive determination of the water molecules diffusion motion on the microscopic determination of the human body. It can provides functional information and can be used for the detection and characterization of pathologic processes. In this paper, the study is analyze dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI), diffusion weighted imaging (DWI) to explore diagnostic value of magnetic resonance imaging in esophageal cancer’s T staging.Materials and Methods35patients with esophageal carcinoma were recruited from the December2011and January2013in the first affiliated hospital of zhengzhou university. All patients had not magnetic resonance contrain dications, radiation therapy and chemotherapy. All patients had MRI routine scan, DWI scans;but only12patients had DCE-MRI.25males and10females were involved,ranking from28to74, the average age56±7.8years. Clinical symptoms is mainly dysphagia, some accompanied with chest pain.35cases with upper segment esophageal cancer (3cases), middle esophageal25cases, low segment esophageal cancer7cases.Siemens Magnetom Trio Tim3.0T magnetic resonance instrument is used for MRI routine scan, DWI (b=300,500,800), dynamic enhancement. According to the different b value and the size of the lesions,we measured the ADC values for three on the best level.Then we calculate the average,at the same time,we measured the ADC values of normal esophagus wall as comparison.DCE-MRI use the contrast agent Magnevist(GD-DTPA) as contrast medium,high pressure injector,with a dose0.2ml/kg,injecting at the speed of2.0ml/s.Injecting GD-DTPA and enhance image scanning at the same time and injection of2.0ml/s into the wash pipe after injecting GD-DTP. It collected12phases in all.SPSS15.0statistical software was used to analysis the data. All of the data using the mean and standard deviation (x±SD). We compare the ADC value of esophageal carcinoma with the normal esophagus using the method of paired t test. When P＜0.05,the data had a significant statistical significance. Kappa test was used to determine whether MRI T staging and pathological staging of esophageal cancer. If the Kappa＞0.75, both good consistency; If the Kappa value between0.4-0.75, the consistency is good; If the Kappa<0.40, both consistency is bad.ResultsIn the35cases, because the T1stage cases is little,so in this paper, we combine the carcinoma in situ with T1stage. T1stage cases is5,9case with T2stage,13cases with T3stage,8cases with T4stage. It is only1case of esophageal adenocarcinoma, and others are esophageal squamous carcinoma. In the35cases,uper lesions is3cases,25cases in the middle,7cases in the low.In the35cases,the lesions in the27cases were obviously diffusion stricted on the DWI, and the lesions were low signal on the ADC;8cases patients on the DWI can not seen obvious diffusion limited high signal. We choose different b value (b=300、500、800s/mm2), the ADC values of the esophageal carcinoma are lower than normal esophagus; the ADC value of esophageal carcinoma and normal esophagus was significantly negative correlation with b value,with the increase of b value,the ADC values is decline. When b value is300s/mm2, the ADC of normal esophagus is3.65±0.78x10-3mm2/s, the ADC value of esophageal carcinoma is2.26±0.12x10-3mm2/s; When b=500s/mm2, the ADC of normal esophagus is3.14±0.31×10-3mm2/s, the ADC value of esophageal carcinoma is1.85±0.52×10-3mm2/s; B=800s/mm2, the ADC of normal esophagus is2.57±0.65×10-3mm2/s, the ADC value of esophageal carcinoma is1.53±0.43×10-3mm2/s.The area under the ROC curve in different b values were0.704,0.731、0.7699. The highest accuracy was that when b value is500s/mm2.The accuracy of the three scanning method of Routine MRI sequence, routine MRI sequence+DWI and routine MRI+DWI+DCE-MRI for esophageal carcinoma T stage were respectively57.1%,68.9%and66.7%compared with pathological results.whether esophagus carcinoma invaded vital organs (pericardium, tracheal bronchus, aorta, etc.) on MRI and compared with its pathological results show that the accurate diagnosis of32cases,only7cases have invaded surrounding organs,25cases have not invaded surrounding organs; Underestimate for1case, overvalued in2cases. The sensitivity, specificity and accuracy of MRI assessing esophageal cancer resectability can be87.5%,92.6%and91.4%.Conclusions1、DWI technology can improve the accuracy of esophageal cancer diagnosis, recommending b=500s/mm2was to the proper b value for esophageal cancer diagnosis and differential diagnosis.2、MRI shows high accuracy in T3and T4stage of esophageal lesions diagnosis, but the accuracy of T1, T2stage lesions is relatively low.3、MRI can accurately assess preoperative esophageal respectively.