Relationship Between Computed Tomography Manifestations of Thymic Epithelial Tumors and the WHO Pathological Classification

Abstract

Objective: To explore the relationship between computed tomography (CT) manifestations of thymoma and its WHO pathological classification. Methods: One hundred and five histopathologically confirmed cases were collected for their pathological and CT characteristics and results were statistically compared between different pathological types of thymoma. Results: Tumor size, shape, necrosis or cystic change, capsule integrity, invasion to the adjacent tissue, lymphadenopathy, and the presence of pleural effusion were significantly different between different pathological types of thymomas (P <0.05). Type B2, B3 tumors and thymic carcinomas were greater in size than other types. More than 50% of type B3 tumors and thymic carcinomas had a tumor size greater than 10 cm. The shape of types A, AB, and B1 tumors were mostly round or oval, whereas 75% of type B3 tumors and 85% of thymic carcinomas were irregular in shape. Necrosis or cystic change occurred in 67% of type B3 thymomas and 57% of thymic carcinomas, respectively. The respective figures for capsule destruction were 83% and 100% . Increases in the degree of malignancy were associated with increases in the incidence of surrounding tissue invasion: 33%, 75%, and 81% in type B2, type B3, and thymic carcinomas, respectively. Pleural effusion occurred in 48% of thymic carcinomas, while calcification was observed mostly in type B thymomas. Conclusions: Different pathological types of thymic epithelial tumors have different CT manifestations. Distinctive CT features of thymomas may reflect their pathological types.

Predicting Subtypes of Thymic Epithelial Tumors Using CT: New Perspective based on a Comprehensive Analysis of 216 Patients

“…The lobulation rate is between 60% and 89% based on previous study23. Focusing on common CT manifestation parameters, we detected that size, boundary, capsule, homogeneity, septa, necrotic or cystic change, pleural effusion, lymphadenopathy, and invasion of adjacent tissues demonstrated significant differences among the 6 TETs subtypes, which confirms previous findings1415161718. However, there was no significant difference for tumor shape among the different pathological types of TETs (P = 0.206), which is inconsistent with previous studies1415161718.…”

“…However, current CT scan cannot effectively differentiate different WHO pathological classifications14. Although several studies have suggested that CT manifestation parameters (tumor size, shape, necrosis or cystic change, capsule integrity, invasion to the adjacent tissue, lymphadenopathy, the presence of pleural effusion, etc) demonstrated significant differences in different TETs types1415161718192021, up to date these parameters could not effectively predict WHO classifications with satisfactory sensitivity and specificity. Besides, the sample sizes of these studies are relatively small, which limits their ability to provide a precise answer for our research question of interest.…”

Conflicting or complementary role of computed tomography (CT) and positron emission tomography (PET)/CT in the assessment of thymic cancer and thymoma: our experience and literature review

“…Conversely, only the presence of lobulated contours was equally distributed in both patient populations, while the residual CT data (such as necrotic or cystic component and calcifications) were different. Studies by Sadohara et al ., Jeong et al ., and Liu et al . focused on the differentiation among low and high‐risk thymoma, and thymic cancer.…”

Diffusion-weighted MR Imaging in Thymic Epithelial Tumors: Correlation with World Health Organization Classification and Clinical Staging

“…but it cannot accurately differentiate between different subtypes of WHO classifications (11)(12)(13)(14)(15)(16)(17)(18). The importance of CT findings to distinguish early and late clinical stages has already been described (1)(2)(3)(4)16).…”