Microscopic Thymoma and Myasthenia Gravis

A Clinicopathological and Immunohistochemical Study of Two Cases
  • F. Puglisi
  • C. Di Loreto
  • N. Finato
  • C. Marchini
  • C. A. Beltrami

Abstract

The term “microscopic thymoma” (MT) was first used by Rosai and Levine1 to describe an occasionally discovered microscopically sized thymic lesion with the histological features of a thymoma. Since then, to the best of our knowledge, other 5 cases of MT were described in patients suffering from myasthenia gravis (MG).2–4 Approximately 30–60% of patients with thymomas develop MG but probably this percentage is underestimated because of the possible presence of thymomas with very small dimensions in some myasthenic patients. In a previous paper we suggested the importance of establishing the unequivocal presence of a thymoma in myasthenic patients by obtaining histological samples of the entire gland, especially in those cases without macroscopical evidence of thymoma.3 In the current paper we describe the histopathological and immunohistochemical features of two cases of MT detected after sampling of the surgically removed thymuses from myasthenie patients.

Keywords

Thymic Epithelial Tumor Disperse Chromatin Myasthenic Patient Entire Gland Epithelial Nest 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • F. Puglisi
    • 1
  • C. Di Loreto
    • 1
  • N. Finato
    • 1
  • C. Marchini
    • 2
  • C. A. Beltrami
    • 1
  1. 1.Institute of Anatomic PathologyUniversity of UdineItaly
  2. 2.Department of NeurologyUniversity of UdineItaly

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