Natural killer cell neoplasm: biology and pathology

Abstract

Natural killer (NK) cell neoplasm is a heterogeneous disease group. In the latest World Health Organization (WHO) classification of tumours of hematopoietic and lymphoid tissues (2008), disease entities considered as NK-cell derivation include NK-lymphoblastic leukemia/lymphoma, chronic lymphoproliferative disorders of NK cells, aggressive NK-cell leukemia, and extranodal NK-cell lymphoma, nasal-type. Despite recent advances in NK-cell research, which have expanded our understanding of the biology of NK-cell neoplasm, it cannot yet be sharply delineated from myeloid neoplasms and T-cell neoplasms even in some "well-known" entity, such as extranodal NK/T-cell lymphoma. This review describes current knowledge of the biology of NK cells and pathology of NK neoplasms as classified in the 2008 WHO classification of tumours of hematopoietic and lymphoid tissues.

Comparison of Diagnostic Cytomorphology of Natural Killer/T-Cell Lymphoma (Nasal Type) in Conventional Smears, Liquid-Based Preparations, and Histopathology

“…The disease is more prevalent among Asians and Native Americans as compared with the populations in the western countries [1–3]. In the majority of cases, this disease occurs in the nasal cavity and other parts of the upper aerodigestive tracts.…”

Blastic plasmacytoid dendritic cell neoplasm: A case report and literature review

“…These observations, along with the characteristic morphology and cytogenetic findings in the present case, indicated that the disease was consistent with the features of leukemic BPDCN. The main differential diagnosis for leukemic BPDCN is acute leukemia of ambiguous lineage, particularly the provisional entity NK-cell lymphoblastic leukemia/lymphoma (NK-LL/L) (4,13). Based on the 2008 WHO classification (4), in cases where BPDCN is excluded, the diagnosis of NK-LL/L may be considered when absence of B-cell or myeloid cell markers, negative TCR gene rearrangement and expression of CD56 with immature T-associated markers (such as cytoplasmic-CD3, CD7 and CD2) are observed (4).…”

Primary Central Nervous System Extranodal NK/T Cell Lymphoma, Nasal Type, with Antecedent Hemophagocytic Syndrome in a Child

“…Cytotoxic molecules such as TIA1, granzyme B, and perforin are positive. CD43 is commonly expressed, and occasional cases are positive for CD30 [16].…”

“…Most NKTCLs derive from NK-cell lineage, whereas NK-like cytotoxic T-cell derivation is postulated in a minor population of this disease because tumor cells express a part of the T-cell markers and show a TCR gene rearrangement [16,17], Of the 4 TCR gene complexes, the TRG@ is the most suitable for diagnostic PCR, as it consists of only 4 V gene families with 16 gene segments and 5 J gene segments, which can all be covered by a small number of primers [18]. We adopted a highly sensitive multiplex PCR method and analyzed the amplified PCR products by heteroduplex capillary electrophoresis, which is more sensitive and specific than conventional gel electrophoresis [10].…”