Abstract
Background The discrimination between reactive and malignant cell populations in some patients with suspected T-cell lymphoproliferative disorders can be complicated and less straightforward. Often, the dilemma lies in determining whether a population of lymphocytes is reactive or neoplastic. In such cases, T-cell receptor (TCR) gene clonality studies have proved useful as an additional diagnostic tool. The TCR gamma gene is a preferred target for TCR gene clonality as it is rearranged at an early stage of T lymphoid development, rearranged in a large percent of T-cell neoplasms, and also because of its relative structural simplicity.
Materials and methods In the present study, we used the BIOMED-2 multiplex primer panel to assess the value of TCR gamma gene rearrangement using genescan analysis in 30 patients with suspected T-cell neoplasms and to elucidate its possible role in the diagnosis of such disorders.
Results TCR gamma gene clonality was detected in all 18 patients with suspected T-cell acute lymphoblastic leukemia/lymphoblastic lymphoma. In contrast, it was detected in nine out of 12 patients (75%) with suspected peripheral T-cell lymphoma. It is known that TCRy monoclonality in peripheral T-cell lymphoma can be detected in patients with more aggressive disease in terms of both clinical presentation and laboratory results. V gamma fl was the most frequently used V gamma segment in our patients. The sensitivity and specificity of genescan were found to be 0.89 and 0.67, respectively, as compared with histopathology.
Conclusion It is concluded that TCR gamma gene clonality is a very useful diagnostic tool in T-cell neoplasms. As it is relatively simple, it can be used as a preliminary test for clonality assessment, followed by the more complex TCR beta gene rearrangement only in negative cases to improve sensitivity. In addition, it should be used together with heteroduplex and interpreted within the clinical context to improve its specificity. (C) 2012 The Egyptian Society of Haematology.