AB thymoma with atypical type A component with delayed multiple lung and brain metastases

• Verfasst von: Grajkowska, Wiesława [VerfasserIn]
• Verfasst von: Marx, Alexander [VerfasserIn]
• Verfasst von: Weis, Cleo-Aron Thias [VerfasserIn]
• Titel: AB thymoma with atypical type A component with delayed multiple lung and brain metastases
• Verf.angabe: Wieslawa Grajkowska, Ewa Matyja, Jacek Kunicki, Sylwia Szymanska, Alexander Marx, Cleo-Aron Weis, Renata Langfort, Malgorzata Szolkowska
• Jahr: 2017
• Umfang: 7 S.
• Fussnoten: Gesehen am 23.07.2018
• Titel Quelle: Enthalten in: Journal of thoracic disease
• Ort Quelle: Hong Kong : Pioneer Bioscience Publ., 2009
• Jahr Quelle: 2017
• Band/Heft Quelle: 9(2017), 9, Seite E808-E814
• ISSN Quelle: 2077-6624
• DOI: doi:10.21037/jtd.2017.07.95
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1577831934

Abstract

An atypical type A thymoma is a newly added entity to the last World Health Organization (WHO) histological classification [2015] of uncertain prognosis. The conventional type A and AB thymomas are usually locally aggressive neoplasms that rarely metastasize with distant metastases to the central nervous system (CNS) occurring extremely exceptionally. We present a history of a woman with a mediastinal tumor originally considered to be a Masaoka-Koga stage II “mixed thymoma with well-differentiated thymic carcinoma component” according to the historic Müller-Hermelink nomenclature. By applying the criteria of the new WHO classification the tumor should be reclassified as an AB thymoma with an atypical A component. The patient developed metastases to the lung and brain 10 and 15 years after the original diagnosis, respectively. All metastases morphologically corresponded to an atypical A component of primary thymoma. Molecular study revealed GTF2I mutations in the primary and one of the metastatic tumors. To our knowledge, this is the first description of a GTF2I mutation in AB thymoma with atypical A component and its metastases. The presented case highlights the necessity of an accurate microscopic search for atypical areas in A or AB thymomas because of their potentially negative impact on prognosis.