Immunocytochemistry in head and neck aspirates. Diagnostic application on direct smears in 16 problematic cases
1Department of Pathology, City Hospital of Sondrio, Italy.
Insights
Immunocytochemistry on fine needle aspiration smears aids head and neck tumor diagnosis. This technique clarifies cell lineage in undifferentiated tumors and aids in identifying specific cancer types.
Area of Science:
- Oncology
- Pathology
- Cytology
Background:
- Fine needle aspiration (FNA) biopsy is crucial for diagnosing head and neck lesions.
- Immunocytochemistry (ICC) can enhance diagnostic accuracy in cytopathology.
Purpose of the Study:
- To evaluate the utility of immunocytochemical staining on routinely processed FNA smears for diagnosing head and neck tumors.
- To assess the effectiveness of ICC in identifying cell lineage and specific tumor types.
Main Methods:
- ICC was performed on alcohol-fixed or air-dried FNA smears from 16 head and neck tumors.
- A streptavidin-biotinylated peroxidase labeling method was used with commercially available monoclonal antibodies.
- Specific antibodies included cytokeratin, leukocyte common antigen, S-100 protein, vimentin, thyroglobulin, CD15, and CD30.
Main Results:
- ICC provided conclusive cell lineage evidence in 12 cases with unclassifiable or undifferentiated cells.
- ICC facilitated correct identification and differential diagnosis of four additional tumors, including metastatic thyroid carcinoma, parathyroid adenoma, and synovial sarcoma.
- Reed-Sternberg cells were identified in a case of Hodgkin lymphoma using CD15 and CD30 immunostaining.
Conclusions:
- Immunocytochemical staining is a convenient and advantageous method for direct smears of aspirated head and neck lesions.
- ICC significantly improves diagnostic accuracy, especially for undifferentiated or difficult-to-classify tumors.
- Careful selection of cases for ICC is recommended to maximize diagnostic yield.
Abstract:
This report describes our experience with immunocytochemical staining of routinely processed smears in the fine needle aspiration (FNA) biopsy diagnosis of 16 tumors of the head and neck. Immunocytochemistry (ICC) was performed on alcohol-fixed or air-dried smears using commercially available monoclonal antibodies followed by a streptavidin-biotinylated peroxidase labeling method. In 12 aspirates with cytologically unclassifiable and undifferentiated cells, immunostaining for cytokeratin, leukocyte common antigen, S-100 protein and vimentin provided conclusive evidence of cell lineage. ICC permitted the correct identification and differential diagnosis of four additional tumors: a positive immunoreaction for thyroglobulin identified a metastatic Hürthle cell carcinoma of the thyroid; a coexpression of two distinct classes of intermediate filaments helped support the FNA diagnoses of a parathyroid adenoma and of a synovial sarcoma; and the double immunoreaction for CD15 and CD30 antigens helped identify Reed-Sternberg cells within an unusually suppurative harvest. Two immunostains were required for proper diagnosis in 13 cases and four in the remaining 3. In all cases but one only unstained slides were used. These data demonstrate that immunostaining can conveniently and advantageously be performed on direct smears of aspirated samples of head and neck lesions, but cases should be carefully selected for this procedure.
