Extranodal NK/T cell lymphoma

Abstract

Extranodal natural killer (NK)/T cell lymphoma (ENKTL) is a distinct subtype of Non-Hodgkin's lymphoma mainly involving the nasal area. Since the entity was first recognized, treatment strategies have been evolving from anthracycline-based chemotherapy and radiotherapy to L-asparaginase containing regimens and recently immune checkpoint inhibitors. With the currently used combined chemotherapy and radiotherapy, more than 70% of patients with localized disease can be cured. L-asparaginase containing regimens have significantly improved treatment outcomes among patients with advanced disease. However, the treatment outcomes of patients with disease refractory to L-asparaginase containing regimens or who experience recurrence remain poor. In this article, we cover the current treatments for ENKTL and emerging treatment approaches.

Aggressive T‐cell lymphomas: 2021 Updates on diagnosis, risk stratification and management

“…The ENKL‐nasal type form is about 1%–2% of all NHL 1,77 . The ENKTL cells express CD2, CD3, CD45, CD56, and ICAM‐1 78 These mostly present as extranodal lymphomas characterized by vascular damage and destruction, necrosis, cytotoxic phenotype and presence of the EBV genome in the tumor cells. Note, ENKL are chemoresistant in part due to the high expression of P‐glycoprotein genes leading to drug resistance 79 .…”

“…Other important pathways include activation of the NOTCH pathway, upregulation of aurora kinase A which regulates mitosis, and upregulates the TP53 pathway to increase expression of survivin (BIRC5), and activation of the hypoxia induced pathway alpha which may promote tumorigenesis and angiogenesis 10 . These tumors tend to be radiosensitive and incorporation of radiotherapy has resulted in improved outcomes at least in limited disease 78 . The treatment paradigm for ENKL is shown in Figure 3.…”

Primary colon natural killer (NK)/T-cell lymphoma, nasal type, with perforations: a case report and literature review

“…Primary colonic ENKTL-NT is very rare and difficult to identify in the early stages due to the lack of characteristic clinical symptoms and other evidence. Although histologically ENKTL-NT presents as an ulcerative granuloma, differential diagnosis by endoscopic examination is difficult because of other benign Case Report granulomatous proliferative diseases of the colon and malignant neoplasms, which can easily lead to misdiagnosis, and the final diagnosis depends on immunohistochemical analysis of tissue specimens (5). Here, we present a rare case of primary colonic ENKTL-NT, in accordance with the CARE reporting checklist (available at https://dx.doi.…”

“…ENKTL-NT begins with abnormal transformation and proliferation of EBV-infected NK cells or T-cells (4). More than 70% of ENKTL-NT cases occur in the nose and the tumor is confined to the adjacent area, but can occur at other sites (5). In an epidemiological study, it was noted that the distribution of ENKTL-NT subtypes did not correlate with country geography or ethnicity (6).…”

Primary Gastrointestinal T/NK Cell Lymphoma

“…L-Asparaginase or pegylated asparaginase containing regimens are widely used in the treatment of advanced and relapsed/refractory ENKTL [ 26 , 27 ]. Since the outcomes of various treatment regimens currently used are still poor, several novel approaches targeting for PD-1/PD-L1 [ 28 ], LMP1/LMP2 [ 29 ], and JAK/STAT pathway (NCT02974647) are being conducted in ENKTL [ 30 ], and STAT5 [ 31 , 32 ] in MEITL. In ALCL, CHOP or CHOP plus etoposide remains the first-line therapy [ 33 ] and recent clinical trials with anti-CD30 antibody (brentuximab vedotin) have shown substantial activity in the relapsed or refractory disease [ 34 ] and front-line treatment [ 35 ].…”