Analysis of clonality in cytologic material using the polymerase chain reaction (PCR)

Area of Science:

• Molecular diagnostics
• Hematopathology
• Oncology

Background:

• Fine needle aspiration (FNA) is a minimally invasive diagnostic technique.
• Distinguishing between reactive lymphoid hyperplasia and B-cell non-Hodgkin's lymphoma (B-NHL) can be challenging morphologically.
• Immunoglobulin heavy chain (IgH) gene rearrangement analysis is a molecular method for assessing lymphoid clonality.

Purpose of the Study:

• To evaluate the utility of PCR-based IgH gene rearrangement analysis in FNA specimens for diagnosing B-NHL.
• To determine the feasibility and accuracy of this molecular technique in FNA samples.

Main Methods:

• 27 FNA specimens were analyzed, including reactive hyperplasia, B-NHL, Hodgkin's disease, and suspicious cases.
• PCR-based IgH gene rearrangement analysis was performed on extracted DNA.
• Results were categorized as polyclonal, monoclonal, or unsuccessful amplification.

Main Results:

• Satisfactory amplification was achieved in 23 out of 27 cases (85.2%).
• A polyclonal pattern, indicative of reactive hyperplasia, was observed in 14 cases.
• A monoclonal band, suggestive of B-NHL, was detected in nine cases (eight B-NHL, one reactive hyperplasia).
• Amplification failed in four cases.

Conclusions:

• PCR-based IgH gene rearrangement analysis is applicable to FNA material for lymphoid lesion diagnosis.
• This molecular method can aid in differentiating reactive lymphoid hyperplasia from B-NHL.
• Interpretation of IgH gene rearrangement results should be integrated with morphological findings and clinical information.