OBJECTIVETo analyze the clinical and laboratory features of 9 cases of gammadeltaT cell lymphoma or leukemia.

METHODSFrom 2007 to 2011, 9 patients with gammadeltaT-cell lymphoma/leukemia were diagnosed in our hospital. The immunophenotype of the abnormal cells were detected by flow cytometry, clonal gene rearrangement of IgH, TCRgamma, TCRdelta by PCR, chromosome karyotype analysis by G banding, acute leukemia gene and the DNA of type 1 - 8 human herpes virus by multiple nested PCR, The gammadeltaT cells were determined by T cell with TCR gammadelta chain, the malignant gammadelta T cells by the abnormal expression of T cell antigens and the precursor malignant gammadelta T cells by the expression of CD34, TDT, CD99, CD1 a or acute leukemia genes.

RESULTSIn the 9 patients with gammadeltaT cell lymphoma leukemia, significant malignant gammadeltaT cells infiltration of bone marrow were found in 8 with blast morphology. 5 were diagnosed as T-ALL/LBL (gammadeltaT type) and 4 HSgammadelta TCL. The clonal gene rearrangement of TCRgamma and/or TCRB were detected in 6/6 patients. Patients either did not achieve complete remission(CR) after induction therapy or relapsed quickly after CR. Only 4/5 patients remained continuous CR(CCR) at 2, 2, 3,12 months respectively, after allogeneic hematopoietic stem cell transplantation (allo-HSCT), the fifth T-ALL (gammadeltaT) relapsed 1 month after allo-HSCT.

CONCLUSIONSThe incidence of gammadelta T cell lymphoma or leukemia may be higher than reported, part of them were T-ALL/LBL with poor prognoses. FCM and clonal gene rearrangement of TCRgamma and/or TCRdelta are helpful to diagnosis. Allo-HSCT may be the only curative approach.