Diagnostic and Clinical Significance of KIT(CD117) Expression in Thymic Epithelial Tumors in China

  • Song, Nan (Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine) ;
  • Chen, Gang (Department of Pathology, Shanghai Pulmonary Hospital, Tongji University School of Medicine) ;
  • Zhang, Peng (Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine) ;
  • Liu, Ming (Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine) ;
  • He, Wen-Xin (Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine) ;
  • Jiang, Ge-Ning (Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine)
  • Published : 2012.06.30


Aims: To study KIT (CD117) expression in thymic epithelial tumors in China, and investigate diagnostic and clinical significance. Material and Methods: Thymic epithelial tumors (TETs) from 102 patients (3 type A, 29 type AB, 5 type B1, 22 type B2, 29 typeB3 and 16 thymic carcinomas) were examined. Immunohistochemical staining with an antic-kit monoclonal antibody was performed on a tissue microarray. Relationships between KIT positive expression and the TET clinical characteristics (WHO histologic classification and Masaoka stage system) were analysed. Results: The KIT positive expression rate was significantly higher in thymic carcinoma (60%, 9/16) than in thymoma (8%, 7/86), a strong correlation being found with the WHO classification, but not the Masaoka tumor stage. The overall survival for patients with KIT positive lesions was significantly worse. Conclusions: KIT is a good molecule marker to differentially diagnose thymic carcinoma from thymoma, while also serving as a predictor of prognosis for TETs. Further research into KIT mutations in Chinese TETs should be conducted to assess the efficacy of targeted therapy.


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