PT - JOURNAL ARTICLE AU - Ali Ismail AU - Jawed A Mallick AU - Dahui Qin AU - Mohammad O Hussaini TI - Sentinel case of Richter transformation from chronic lymphocytic leukaemia/small lymphocytic lymphoma to CD3+ diffuse large B-cell lymphoma AID - 10.1136/jclinpath-2016-204024 DP - 2017 Jul 01 TA - Journal of Clinical Pathology PG - 575--578 VI - 70 IP - 7 4099 - http://jcp.bmj.com/content/70/7/575.short 4100 - http://jcp.bmj.com/content/70/7/575.full SO - J Clin Pathol2017 Jul 01; 70 AB - Aim To report the first case of a Richter syndrome where small lymphocytic lymphoma (SLL) progressed to a CD3+ diffuse large B-cell lymphoma (DLBCL).Methods Macrodissection of small and large cell lymphomatous components was performed. This was followed by flow cytometric analysis along with molecular B-cell immunoglobulin (heavy and light chains) and T-cell receptor (γ and β chains) gene rearrangement studies to investigate a clonal relationship between the components.Results The immunophenotypic profile was similar between small and large cell components of the lymphoma by flow cytometry. Furthermore, shared clonal peaks were observed between both components based on molecular B-cell and T-cell receptor gene rearrangement studies, confirming a clonal relationship.Conclusions Chronic lymphocytic leukaemia/SLL may rarely undergo Richter transformation to a DLBCL demonstrating lineage infidelity. This is a potentially important diagnostic pitfall and such cases should not be confused with a de novo T-cell lymphoma.