Utility of Flow Cytometry in Diagnosing Hematologic Malignancy in Tonsillar Tissue

Area of Science:

• Pathology
• Hematology
• Oncology

Background:

• Tonsil biopsy and excision are common procedures.
• Lack of consensus guidelines for tonsil specimen handling exists.
• Accurate diagnosis of tonsillar hematologic malignancy relies on histology, immunohistochemistry, and flow cytometry.

Purpose of the Study:

• To assess the accuracy and use patterns of flow cytometry in tonsil specimen diagnosis.
• To evaluate the utility of flow cytometry in identifying tonsillar hematologic malignancies.
• To compare flow cytometry findings with histology and immunohistochemistry in tonsil pathology.

Main Methods:

• Retrospective analysis of 154 surgically biopsied or excised tonsil specimens evaluated with flow cytometry (August 2011 - March 2014).
• Inclusion of patient clinical information, intraoperative frozen section, histology, immunohistochemistry, and flow cytometry diagnoses.
• Analysis focused on accuracy and use patterns of flow cytometry.

Main Results:

• Hematolymphoid malignancy was diagnosed in 6 adult patients via histology/immunohistochemistry.
• Flow cytometry identified abnormal populations in 5 of 6 malignancy cases.
• Flow cytometry detected clonal populations in 2 cases of reactive follicular hyperplasia.
• Histology and flow cytometry were benign in 96.1% of cases.

Conclusions:

• Flow cytometry demonstrated lower accuracy than histology/immunohistochemistry for tonsillar hematolymphoid malignancy diagnosis.
• Intraoperative frozen section diagnosis showed high sensitivity for malignancy, aiding triage for flow cytometry.
• Pediatric patients constituted nearly half of the study cohort, despite the rarity of tonsillar lymphoma in children.