The Control Study Between The Multi-slice CT Diagnosis And Pathology Of Thymic Epithelial Tumors

Part one The control study between the multi-slice CT findings and simplified pathological typing of thymic epithelial tumors.Purpose: To evaluate the clinical value of the multi-slice CT finding of thymic epithelial tumors in predicting the simplified pathological typing by analyzing the correlation between the multi-slice CT findings of thymic epithelial tumors and simplified pathological typing.Materials and Methods: Collecting 52 thymic epithelial tumors patients in our hospital from 2007 September to 2014 December with complete data and proved by pathology, classifying type A、AB and B1 as low-risk thymomas,type B2、B3 as high risk thymomas,thymic carcinomas as an independent group.The CT findings of 52 cases were reviewed by two radiologists,including the location, morphology, size(long diameter, short diameter and height), edge, density(homogenous or not,cystic degeneration region,necrosis region),the CT value of the soft tissue region of plain and enhanced scan,the degree of enhancement,mediastinal fat line,mass- cardiovascular inferface,pleural or pericardial invasion,the adjacent vascular invasion,lymph node metastasis and other organ distant metastasis. Statistical analysis of image data above was performed by SPSS21.0 and summarized the correlation the multi-slice CT finding of thymic epithelial tumors and simplified pathological typing.Results: The 52 cases include 30 cases of low-risk thymomas、17 cases of high risk thymomas、5 cases of thymic carcinomas.There is no statistically significant difference among the size(long diameter, short diameter and height)、the CT value of plain and enhanced scan、the degree of enhancement、the location、cystic degeneration region or necrosis region、calcification、pleural or pericardial invasion、the adjacent vascular invasion(P﹥0.05). There is statistically significant difference among the morphology, edge, homogenous density or not, mediastinal fat line,mass- cardiovascular inferface,lymph node metastasis and other organ distant metastasis(P﹤0.05).Conclusionthe: tumor more shows Irregular shape、rough edge、heterogeneous density 、 mediastinal fat line blurred or disappeared 、 mass-cardiovascular inferface appearing as moulten shape、lymph node multiple metastases metastasis and other organ distant metastasis more prompt the high-risk group or thymic carcinoma, have a certain value in identifying form the low risk group. The CT features of thymoma in high risk group and thymic carcinoma overlap a lot, there is limited value in identifying the groups.Part two The value of CT perfusion imaging in predicting the grade malignancy of thymic epithelial tumorsPurpose: To evaluate the clinical value of CT perfusion parameters of thymic epithelial tumors in predicting the grade malignancy by applicating multi-slice spiral CT perfusion imaging.Materials and Methods: Collecting the anterior mediastinal tumor patients in our hospital from 2013 January to 2014 December which taked the CT perfusion imaging voluntarily. Referring to the grouping scheme of thymic epithelial tumors of Jeong et al, the patients of thymic epithelial tumors proved by pathology were divided into three groups: the low-risk group(type A、AB and B1)、the high-risk group(type B2、B3)and the thymic carcinomas. To compare the CT perfusion parameters among the three groups, including blood flow、blood volume、mean transit time、surface permeability, and analyse the clinical value of CT perfusion parameters in predicting the grade malignancy of thymic epithelial tumors.Results: 24 thymic epithelial tumors patients proved by pathology were enrolled in this study, including 12 cases of the low-risk group、10 cases of the high-risk group and 2 cases of thymic carcinomas. With the development of thymic epithelial tumors from the low-risk group to the high-risk group and the thymic carcinomas,the value of BF、BV and PS showed a decreasing trend, the value of MTT showed an increasing trend. There is statistically significant difference among the value of BF、BV、MTT and PS(P﹤0.05). All the CT perfusion parameters of the three groups were compared with each other, the difference of the value of BF、BV、MTT and PS between thymic carcinomas and the low-risk group、the high-risk group have statistical significance(P﹤0.05), but have not statistical significance between the low-risk group and the high-risk group(P>0.05).Conclusion: The CT perfusion parameters of thymic epithelial tumors have limited value in identifying the grade malignancy between the low-risk group and the high-risk group. Although in this study, the perfusion parameters can contribute to identify thymic carcinoma and the low risk group 、the high risk groups, but due to the small number of cases of thymic carcinoma, the application value needs to be further researched.