Related Experiment Video
Updated: Feb 17, 2026
05:39
Spontaneous Murine Model of Anaplastic Thyroid Cancer
Published on: February 3, 2023
2.3K
AB thymoma with atypical type A component with delayed multiple lung and brain metastases
Wieslawa Grajkowska1,2, Ewa Matyja2, Jacek Kunicki3
1Department of Pathology, The Children's Memorial Health Institute, Warsaw, Poland.
Journal of Thoracic Disease
|December 10, 2017
Summary
A rare atypical thymoma subtype, AB thymoma with atypical A component, showed late-stage lung and brain metastases. This case, linked to GTF2I mutations, underscores the importance of identifying atypical areas in thymomas for prognosis.
Area of Science:
- Oncology
- Pathology
- Genetics
Background:
- The World Health Organization (WHO) 2015 classification introduced atypical type A thymoma, a subtype with uncertain prognosis.
- Conventional type A and AB thymomas are typically locally aggressive, with rare distant metastases, especially to the central nervous system (CNS).
Observation:
- A patient initially diagnosed with Masaoka-Koga stage II thymoma was reclassified under the new WHO criteria as an AB thymoma with an atypical A component.
- This patient developed lung and brain metastases 10 and 15 years post-diagnosis, respectively, with metastases matching the atypical A component.
Findings:
- Morphological analysis confirmed metastases corresponded to the atypical A component of the primary thymoma.
- Molecular studies identified GTF2I mutations in both the primary tumor and a metastatic lesion.
- This represents the first documented GTF2I mutation in an AB thymoma with an atypical A component and its metastases.
Implications:
- Accurate microscopic identification of atypical areas in type A and AB thymomas is crucial.
- Recognizing these atypical features may significantly impact patient prognosis and treatment strategies.
- This case expands the understanding of thymoma behavior and genetic underpinnings.
