Thymic Epithelial Tumors: Pathological Classification, Prognosis and Tumor Staging

Authors

  • Peerayut Sitthichaiyakul Department of Pathology, Faculty of Medicine, Naresuan University

Keywords:

thymoma, thymic carcinoma, thymic epithelial tumor, pathologic classification, prognosis, staging

Abstract

Thymic epithelial tumors (TETs) including thymoma and thymic carcinoma, are the most common primary anterior mediastinal tumors. They are approximately 17-50% of anterior mediastinal mass detected in patients. The incidence rate of TETs ranges from 1.5 up to 4.9/ million/year. These tumors are infrequent and having indolent growth. Therefore, the studies for accurate biologic features, prognosis and clinical course of the TETs are still limited. Histopathologic features of the tumors are important factors for evaluating the biologic features of TETs. Clinical staging is also an important prognostic factor for the tumors. Complete surgical resection is the treatment of choice for tumors in the early stages. Chemotherapy and radiotherapy are considered for selected patients. Currently, at least 24 histopathologic classifications and 14 staging systems have been proposed. The widely accepted histopathologic classifications and clinical staging systems are summarized and compared in this article. Prognostic factors for TETs are reviewed. Histopathologic patterns, immunohistochemical staining features of the majority of TETs, and guidelines for pathological examination are also summarized to guide accurate pathological diagnosis and tumor staging.

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Published

2018-06-29

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Review Articles