Detection of clonality in cutaneous T-cell lymphomas by PCR analysis

Differentiation of a cutaneous lymphoma from a reactive lymphoid infiltrate is a demanding challenge for the pathologist. In this retrospective study we examined 24 paraffin-embedded tissue samples from lesions diagnosed as lymphomas and 7 control samples of skin affected by benign changes and with pronounced lymphoid infiltrates for clonal rearrangement of the gamma T-cell-receptor. Using PCR technology we demonstrated clonality in 22 cases of lymphoma (92%). Thus, the primer combination used in this study covering the four main groups (I-IV) of the variable region of the gamma T-cell receptor gene allows high sensitivity. No clonality was demonstrable in any of the 7 control cases. This study demonstrates the growing importance of PCR technology for the diagnosis of lymphoma.