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Fibronexus in low-grade myofibrosarcoma: a case report
Kazuo Watanabe1, Mizuko Tanaka, Kusakabe Takashi
1Pathology Division, Fukushima Medical University Hospital, oka, Fukushima City, Fukushima, Japan. w-kazuo@fmu.ac.jp
Ultrastructural Pathology
|June 24, 2008
Summary
Fibronexus, a cellular junction, was identified in a rare low-grade myofibrosarcoma case. This ultrastructural feature may help distinguish myofibrosarcoma from other myogenic tumors.
Area of Science:
- Pathology
- Oncology
- Cell Biology
Background:
- The role of fibronexus, a specific ultrastructural feature, in myofibroblastic tumors remains debated.
- Myofibroblastic tumors encompass a range of neoplastic conditions with myofibroblastic differentiation.
Observation:
- A case of low-grade myofibrosarcoma in an 80-year-old male presented with characteristic histological and ultrastructural findings.
- Tumor cells exhibited spindle morphology, mild nuclear atypia, and positive staining for alpha-smooth muscle actin and desmin.
- Ultrastructural analysis revealed well-developed organelles, myofilaments, fibronectin fibrils, and distinct fibronexus junctions.
Findings:
- The presence of fibronexus was confirmed via ultrastructural examination in this low-grade myofibrosarcoma.
- Immunohistochemistry showed tumor cells positive for alpha-smooth muscle actin and desmin, excluding other markers like h-caldesmon and S-100 protein.
Implications:
- Fibronexus serves as a potentially valuable ultrastructural marker for diagnosing myofibrosarcoma.
- Identifying fibronexus can aid in differentiating myofibrosarcoma from other myogenic sarcomas, improving diagnostic accuracy.
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