Indolent T-cell large granular lymphocyte leukaemia after haematopoietic SCT: A clinicopathologic and molecular analysis

Abstract

Four women and three men after allogeneic (n4) and autologous (n3) haematopoietic SCT (HSCT) were observed to have an increase in T-cell large granular lymphocytes (T-LGLs) of CD3CD8 phenotype for a median of 41 (15-118) months. Clonal rearrangement of the T-cell receptor gene was verified by two PCR techniques and direct DNA sequencing, confirming that the cases were neoplastic and therefore classifiable as T-LGL leukaemia. In the allogeneic HSCT cases, T-LGL leukaemia was derived from donor T cells in three patients, as shown by DNA chimerism analysis, and recipient T cells in one patient who had graft failure previously. None of the patients showed cytopenia, autoimmune phenomenon or organ infiltration, which were features typical of de novo T-LGL leukaemia. Six patients had remained asymptomatic with stable large granular lymphocyte counts. One patient died from cerebral relapse of the original lymphoma. T-LGL leukaemias occurring post-HSCT are distinct from de novo T-LGL leukaemia and may have a different pathogenesis and clinical course. Patients did not require specific treatment, and the disease remained stable for long periods. © 2012 Macmillan Publishers Limited.