[Clinical and Pathological Characteristics of Aggressive Natural Killer Cell Leukemia Patients]

To investigate the clinicopathologic characteristics, diagnosis and therapy of aggressive natural killer cell leukemia (ANKL) patients.

Clinical manifestations, cellular morphology, immunophenotypic analysis by flow cytometry (FCM), TCR gene rearrangement, pathology and Immunohistochemical analysis of bone marrow (BM) were combined to diagnose the six patients with ANKL.

The median age of the patients were 35.5 years old. All the patients with fever, cytopenia and liver dysfunction. Imageological examination presented hepatosplenomegaly (6/6), and PET/CT presented diffusely increased metabolism in liver, spleen and BM (3/3). BM cytologic examination presented increased hematophagocyte at the early stage and 1%-42% leukemic cell were detected in BM with the progression of diseases. FCM showed the leukemic cells were positive for CD2(6/6), CD56(5/6), CD16(2/6), CD94(3/6), CD38(3/6), cCD3(1/5), CD8(1/6), CD7(2/6), CD57(1/6) and negative for CD3, CD4, TdT, cMPO, TCR α/β, TCR γ/δ. The neoplastic cells were negative for TCR gene rearrangement. Five cases showed increased quantitation of whole blood Epstein-Barr virus (EBV) DNA.

ANKL is a highly aggressive disease. Prompt and repeating BM examination is important to patient with fever, cytopenia and liver dysfunction. The diagnosis of ANKL relies mainly on the integration of clinical, morphologic, immunophenotypic finding and EBV-DNA increasement.