Comparison of clinical features and CT findings between atypical thymoma and thymic carcinoma
10.3760/cma.j.issn.1005-1201.2011.12.014
- VernacularTitle:不典型胸腺瘤和胸腺癌的临床与CT表现比较
- Author:
Xiangyang WANG
- Publication Type:Journal Article
- Keywords:
Thymus neoplasms;
Tomography;
X-ray computed;
Diagnosis
- From:
Chinese Journal of Radiology
2011;45(12):1132-1135
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the differences and the similarities of clinical presentations and CT features between type B3 thymoma ( atypical thymoma) and type C thymoma ( thymic carcinoma) in the WHO classification of thymic epithelial tumors.MethodsComplete CT findings of thirty cases of type B3 and seventeen cases of type C thymic epithelial tumors confirmed by histopathology according to WHO 2004 Classification System and clinical features including the prognosis of each case were reviewed retrospectively.Statistical analyses of the data for the age and the long diameter were performed with Independent-Samples t test between the two groups.Statistical analysis for gender,association with myasthenia gravis,method of the operation,contours,shapes,calcification,necrosis,enhancement pattern of the tumors on CT,presence of mediastinal lymphadenopathy,invasion of mediastinal fat,chest wall,pericardium,great vessel,pleural mediastinum,metastasis to the plural,pleural effusion,distant metastasis were performed with Fisher exact test.Kaplan-Meier method was employed for survival analysis.Results Clinical data:the average age of type B3 group was significantly younger ( t = - 2.905,P = 0.006).90.0％(27/30) of patients in type B3 group were complicated by myasthenia gravis,while only 5.9％ (1/17) of patients in type C group were complicated by myasthenia gravis.The difference between the two groups was statistically significant ( P = 0.000 ).The ratio of complete resection of type B3 group ( 80.0％ ) was significantly higher than that in type C group ( P = 0.001 ),70.6％ (12/17) of patients in type C group died within 2 years after surgical resection,while only 20.0％ (6/30) of patients in type B3 group died within one to nine years after surgical resection.Three years'survival ratio of C group was 29.4％,and five years'survival ratio of C group was lower than 14.7％,which was significantly lower than B3 group( five years'survival ratio was 94.7％ ),which was statistically significant (P =0.000).CT features:the average long diameter of tumor in type C group was ( 6.4 ± 2.1 ) cm,significantly longer than that in type B3 group,which was (4.6 ± 2.3) cm (t = - 2.778,P = 0.008 ),and the contour of tumor in type C group usually showed irregularity ( 13/17,76.5％ ),while it usually showed lobulated ( 18/30,60.0％ ) in type B3 group (P = 0.019 ),more necrosis found in C group ( 15/17,88.2％ ) than B3 group ( 17/30,56.7％ ),compared with type B3 group on enhanced CT,more tumor in type C group showed heterogeneous enhancement (P =0.042),and more great vessel invasion ( 15/17,88.2％,P =0.001 ) and more distant metastasis (8/17,47.0％,P = 0.028) occurred in type C group.ConclusionMost of type B3 and type C thymoma have a certain significant difference in clinical factor,prognosis and CT findings,which are helpful for differentiation.
