Molecular Assessment of Clonality in Lymphoproliferative Disorders: II. T-cell Receptor Gene Rearrangements

T-lineage non-Hodgkin's lymphomas are a diverse group of malignancies for which routine histology and immunophenotyping alone may not be diagnostic. Molecular genetic studies can be used to detect unique T-cell receptor gene rearrangements and establish clonality in these cases. The methods for evaluating T-cell receptor clonality are less well studied and produce more varied results than those for the immunoglobulin genes. Whereas clonality is a hallmark of malignancy, its presence or absence in T-lineage disorders does not always correlate with subsequent biologic behavior. Since the molecular testing of T-lineage lymphoproliferative disorders is increasing, this review summarizes the polymerase chain reaction and Southern blotting methods for T-cell receptor gene rearrangements. Interpretation of the results of these methods should always be done in the context of complete clinical and histologic data.