Flow cytometric immunophenotyping in a liquid-based cytology sample of pleural fluid: Connecting the dots

Area of Science:

• Oncology
• Hematology
• Cytopathology

Background:

• Primary mediastinal large B-cell lymphoma (PMBCL) is a distinct subtype of non-Hodgkin lymphoma.
• PMBCL typically affects young adults and presents as a large mediastinal mass.
• Diagnosis in cytology samples, particularly effusions, is infrequent and challenging.

Observation:

• This study reports an uncommon case of PMBCL identified in an effusion sample.
• The case involved a patient with a mediastinal mass.
• Cytological analysis was performed on the effusion fluid.

Findings:

• Flowcytometric immunophenotyping demonstrated a B-cell lineage consistent with lymphoma.
• Immunocytochemistry confirmed the expression of specific markers indicative of PMBCL.
• Diagnostic accuracy was significantly enhanced by these techniques.

Implications:

• Highlights the utility of flow cytometry and immunocytochemistry in diagnosing rare PMBCL cases from cytology specimens.
• Emphasizes the importance of considering PMBCL in the differential diagnosis of mediastinal lesions.
• Suggests these methods can improve diagnostic yield and patient management in challenging cases.