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Evaluation of Tumor-infiltrating Leukocyte Subsets in a Subcutaneous Tumor Model
Published on: April 13, 2015
CD31 immunoreactivity in small round cell tumors
S A Nicholson1, M B McDermott, B R DeYoung
1Lauren V. Ackerman Laboratory of Surgical Pathology, Washington University School of Medicine, St. Louis, Missouri, USA.
Applied Immunohistochemistry & Molecular Morphology : AIMM
|August 11, 2000
Summary
CD31 is a marker for endothelial cells, but its role in small round cell tumors was unclear. This study found CD31 reactivity in some Ewing
Area of Science:
- Oncology
- Immunohistochemistry
- Pathology
Background:
- CD31 is a known marker for endothelial differentiation in human neoplasms.
- The diagnostic utility of CD31 in small round cell tumors remained unevaluated.
Purpose of the Study:
- To investigate the role and diagnostic significance of CD31 expression in various small round cell tumors.
- To determine if CD31 can aid in differentiating between lymphoid and non-lymphoid small round cell neoplasms.
Main Methods:
- Immunohistochemical staining for CD31 was performed on 276 formalin-fixed, paraffin-embedded small round cell tumors.
- Tumor types included Ewing's sarcoma/primitive neuroectodermal tumors, rhabdomyosarcomas, neuroblastomas, and various lymphomas.
- A modified avidin-biotin-peroxidase complex technique with microwave epitope retrieval was utilized.
Main Results:
- CD31 reactivity was observed in a small subset (4/85) of Ewing's sarcoma/primitive neuroectodermal tumors.
- No other non-lymphoid small round cell tumors showed CD31 positivity.
- The majority of well-differentiated, intermediately differentiated, and lymphoblastic lymphomas were CD31 positive, while small cleaved lymphomas showed variable reactivity and small noncleaved lesions were negative.
Conclusions:
- CD31 expression in Ewing's sarcoma/primitive neuroectodermal tumors is uncommon but possible.
- CD31 positivity in a small cell neoplasm does not exclusively indicate hematopoietic origin.
- These findings refine the understanding of CD31's utility in evaluating human neoplasms.
