Kwong YL. Natural killer-cell malignancies: diagnosis and treatment

Department of Medicine, University of Hong Kong, Hong Kong, China.
Leukemia (Impact Factor: 10.43). 01/2006; 19(12):2186-94. DOI: 10.1038/sj.leu.2403955
Source: PubMed


Natural killer (NK)-cell malignancies are uncommon diseases. Previously known as polymorphic reticulosis or angiocentric T-cell lymphomas, they are classified by the World Health Organization as NK/T-cell lymphoma, nasal type and aggressive NK-cell leukemia. They are prevalent in Asia and South America, but exceptionally rare in western countries. Pathologically, NK-cell lymphomas show a polymorphic neoplastic infiltrate with an angioinvasive and angiodestructive pattern. Lymphoma cells are characteristically CD2+, CD56+ and cytoplasmic CD3epsilon+. T-cell receptor gene is germline, and clonal Epstein-Barr virus (EBV) infection is almost invariably. Clinically, they can be divided into nasal, non-nasal, and aggressive lymphoma/leukemia subtypes. Most nasal NK-cell lymphomas present with stage I/II disease, and frontline radiotherapy is the most important key to successful treatment. Many stage I/II patients treated with radiotherapy fail systemically, implying that concomitant chemotherapy may be needed. Chemotherapy is indicated for advanced nasal NK-cell lymphoma, and the non-nasal and aggressive subtypes. However, treatment results are unsatisfactory. High-dose chemotherapy with hematopoietic stem cell transplantation may be beneficial to selected patients. The International Prognostic Index and presentation EBV DNA load is of prognostic significance and may be useful in the stratification of patients for various treatment modalities.

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    • "Others include extranodal NK/T lymphoma, nasal type (ENKL), and aggressive NK cell leukemia (ANKL). Although such EBV-positive T/NK LPDs are relatively rare, therapeutic treatment for those disorders is challenging, and the prognosis of those patients often can be dismal [4], [5]. Therefore, development of effective and specific drugs is an important goal. "
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    PLoS ONE 05/2013; 8(5):e63566. DOI:10.1371/journal.pone.0063566 · 3.23 Impact Factor
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    • "Occasionally, NKcell lymphomas can arise in extranasal sites, involving the skin, gastrointestinal tract, salivary glands, and testis, and are referred to as non-nasal NK-cell lymphomas. Rarely, NK-cell lymphomas can present in a leukemic phase, and are referred to as NK-cell leukemia (Kwong, 2005). NK-cell neoplasms are rare but aggressive lymphomas uniformly associated with EBV infection. "
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