Related Experiment Videos
Intracytoplasmic chromophobe inclusion bodies in an anaplastic meningioma
A Saito1, Y Nakazato, J Hirato
1Department of Pathology, Gunma University School of Medicine, Japan.
Insights
Intracytoplasmic chromophobe inclusion bodies (CIB) were found in an anaplastic meningioma. These inclusions are primarily composed of abnormally synthesized and arranged vimentin filaments.
Area of Science:
- Neuropathology
- Oncology
Background:
- Intracytoplasmic inclusion bodies are uncommon findings in meningiomas.
- Anaplastic meningiomas represent a rare, aggressive subtype of meningioma.
Observation:
- A case of anaplastic meningioma in a 74-year-old woman presented with distinct intracytoplasmic chromophobe inclusion bodies (CIB).
- These CIB exhibited diverse morphologies (round, teardrop-like, fusiform, horse-shoe-like, crescentic, perinuclear) and measured 7-14 microns.
- Tumor cells containing CIB often displayed eccentric nuclei.
Findings:
- Immunohistochemical analysis revealed CIB were predominantly vimentin-positive, staining intensely compared to surrounding cytoplasm.
- Ultrastructural examination showed CIB composed of loosely textured, parallel, and entangled filaments (13-14 nm diameter).
- These filaments were thicker than typical intermediate filaments and appeared studded with granular and fuzzy substances, suggesting abnormal vimentin synthesis and arrangement.
Implications:
- The findings suggest that these CIB are primarily composed of abnormally synthesized and organized vimentin filaments.
- This detailed characterization contributes to the understanding of rare cytological features in aggressive meningiomas.
- Further research may elucidate the specific mechanisms leading to aberrant vimentin aggregation in neoplastic cells.
Abstract:
Intracytoplasmic inclusion bodies are rarely found in meningiomas. A 74-year-old woman had an anaplastic meningioma with intracytoplasmic chromophobe inclusion bodies (CIB) histologically. These CIB were various shapes, e.g. round, teardrop-like, fusiform, horse-shoe-like, crescentic and perinuclear. The size of CIB ranged from 7 to 14 microns and the nuclei of the tumor cells with CIB were often eccentric. Most CIB were immunopositive only for vimentin, staining more intensely than surrounding cytoplasm in a comparative study using adjacent sections stained with hematoxylin-eosin and vimentin. CIB showed loosely textured filamentous structures which were in parallel and entangled arrangements ultrastructurally. The diameter of the filaments was 13-14 nm and they were thicker than normal intermediate filaments. Moreover, these filaments appeared to be studded with granular and fuzzy substances. These findings suggest that CIB are mainly composed of abnormally synthesized and arranged vimentin filaments.