Primary ophthalmic natural killer/T-cell lymphoma: A population-based study.

BACKGROUND: Ophthalmic lymphomas, a subgroup of extra-nodal lymphomas, have seen an increase in incidence in recent decades. Of these, the NK/T-cell lymphoma (NKTL) subtype is particularly aggressive. Though prevalent mostly in Asian patients, data on ophthalmic NKTL is still limited, especially in the western population. This study aimed to provide an additional analysis of primary ophthalmic NKTL using the Surveillance, Epidemiology, and End Results (SEER) database. METHODS: A retrospective analysis was performed on the SEER database covering records from 2000 to 2020. Patients diagnosed with extranodal NKTL originating primarily from an ophthalmic structure were identified. RESULTS: Out of 4540 ophthalmic lymphomas registered in the SEER database between 2000 and 2020, 9 cases (0.2%) corresponded to ophthalmic NKTL, occurring in patients with a median age of 67 years. The majority of these patients underwent chemotherapy (88.8%) and radiotherapy (66.6%). The 6-month overall survival (OS) and cancer-specific survival (CSS) were both at 50.8%, dropping significantly at the 2-year follow-up. CONCLUSION: Primary orbital NKTL has a notably severe prognosis. An early diagnosis is important due to the aggressive nature of NKTL.

Extranodal natural-killer/T-cell lymphoma, nasal type: An immunomorphological study from a regional cancer institute in India.

Introduction: Extranodal natural-killer/T-cell lymphoma, nasal type (ENKTL), is a rare, aggressive, predominantly extranodal non-Hodgkin lymphoma (NHL) of putative natural-killer (NK) cell and rarely T-cell origin, always associated with Epstein-Barr virus (EBV) infection and characterized by highly distinctive histopathological features with predilection for the upper aerodigestive tract. While the nasal cavity is the prototypical site, less frequently extranasal ENKTL can also occur. The objective of this case series is to study the immunomorphological features of ENKTL from a tertiary cancer centre as the data are sparse from India despite it being a distinct entity with characteristic clinicopathological features. Methods: We identified 11 cases of ENKTL from the departmental archives between January 2015 and June 2018. The clinicopathological and immunohistochemistry (IHC) findings of these tumors were analyzed. EBV encoded RNA (EBER) in situ hybridization (EBER-ISH) for EBV was done in eight cases. Results: The disease was more common in males (male: female ratio 1.8:1) with the mean age of 45 years (range 31-65 years). Sinonasal region was the most common site with 9 cases and skin and penis were involved in one case each. The patient with penile involvement on further investigations was found to have occult nasal involvement, Histomorphological features such as angiocentricity/angioinvasion was seen in seven cases (63.6%) and significant necrosis was present in all 11 cases (100%). All cases were uniformly positive for cytoplasmic CD3 and CD56 with high Ki67 proliferating index and EBER-ISH test for EBV was positive in all the eight cases. Conclusion: ENKTL is an aggressive NHL and should be differentiated from other T- and B-cell lymphomas as the prognosis and therapy differ. Nasal biopsies showing predominant necrosis and atypical lymphoid cells with angiocentricity must raise the suspicion of ENKTL and should be confirmed by immunomorphological and molecular studies.

NK- and T-cell lymphoma of the nasal cavity and paranasal sinuses in Denmark 1980-2017: a nationwide cohort study.

Compared to Asian and Latin American populations, sinonasal NK- or T-cell lymphoma is rare in Europe. All patients with sinonasal NK- or T-cell lymphoma in Denmark from 1980 to 2017 were validated histologically, and the disease behavior and demographics were extracted from medical records and national registries. Prognostic factors associated with mortality were determined using survival statistics. We included 56 patients: 40 extranodal NK/T-cell lymphoma (nasal type) (ENKTCL) and 16 peripheral T-cell lymphoma (not otherwise specified) (PTCL). The median age was 66, and most patients were male (72%). The ENKTCL and PTCL 5-year overall survival was 48% and 50%, respectively; progression-free survival was 38% for both. With ENKTCL, stage and performance status increased mortality significantly (HR = 8.6; p < 0.001 and HR = 4.23; p = 0.04). In conclusion, disseminated disease had a dismal outcome and the onset of ENKTCL in this ethnically homogeneous European cohort was about a decade later than reported in Asian populations.

Characteristics and Outcome of Extranodal NK/T-cell Lymphoma in North America: A Retrospective Multi-Institutional Experience.

BACKGROUND: Extranodal natural killer/T-cell lymphoma (ENKTL) is rare and clinical data from non-Asian countries are lacking. It is unclear whether outcomes and disease natural history is similar to reported Asian series. We assessed characteristics and outcomes of patients with ENKTL from major North American centers. PATIENTS AND METHODS: We retrospectively identified patients with newly-diagnosed CD56 + ENKTL and studied disease characteristics and clinical outcomes. RESULTS: One hundred and twenty-one patients with ENKTL diagnosed between June 1990 and November 2012 were identified. Eighty-three patients (69%) had stage I/II disease and were treated with combined modality therapy (CMT) (n = 53), chemotherapy alone (CT) (n = 14) or radiotherapy alone (RT) (n = 16).  Thirty-eight patients (31%) had stage III/IV disease and were treated with CMT (n = 12), CT (n = 23), or RT (n = 3).  The median follow-up for the entire cohort was 51 months. Patients with stage I/II disease, compared to those with stage III/IV disease, had superior 2-year progression free survival (PFS) 43% vs 19% (P = .03) and overall survival (OS) 59% vs. 29% (P= .004). Outcomes were similar for stage I/II patients who received CMT vs. RT alone with 2-year PFS (53% vs. 47%; P= .91) and OS (67% vs. 67%; P= .58). No significant differences in outcomes were noted based on race/ethnicity. CONCLUSIONS: This series represents a large experience of ENKTL treated at several major North American academic centers.  Our data are consistent with Asian studies: (1) majority of patients present with early-stage disease; (2) overall poor outcome regardless of race/ethnicity; (3) CMT likely yields favorable outcomes for suitable candidates with early-stage disease.

Outcome after hematopoietic stem cell transplantation in patients with extranodal natural killer/T-Cell lymphoma, nasal type: A French study from the Société Francophone de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC).

We evaluated the outcome of 65 French patients with Extranodal NK/T-cell lymphoma, nasal type (ENKTL) undergoing hematopoietic stem cell transplantation (HSCT) (19 allogeneic and 46 autologous). Fifty-four patients (83%), most of which receiving L-asparaginase (L-aspa) containing regimens (81%), achieved complete or partial response at time of HCST. After a median follow-up of 79.9 months, 4-years progression-free survival (PFS) and overall survival (OS) were similar in both autologous and allogeneic groups (PFS: 34% vs. 26%, p = .12 and OS: 52% vs. 53%, p = .74). Response status at HSCT was the major independent prognostic factor on survival (OS: HR: 4.013 [1.137; 14.16], p = .031 and PFS: HR: 5.231 [1.625; 16.838], p = .006). As compared to control patients receiving chemotherapy and/or radiotherapy containing regimens only, upfront HSCT did not improve the outcome of responder patients, including those treated by L-aspa. However, it tends to provide survival benefit for relapsed patients with initial high-risk clinical features who achieved second remission. Whereas the place of HSCT in upfront therapy has still to be clarified, these data confirm that HSCT should be considered for consolidation in selected patients with relapsed ENKTL. Based on a large non Asian ENKTL cohort since the L-aspa era, this study provides some insight into the survival patterns of ENKTL patients with HSCT in the Western hemisphere and may give future direction for the next clinical trial design.

Extranodal NK/T cell lymphoma, nasal type: An updated overview.

Extranodal NK/T-cell lymphoma, nasal type (ENKTCL-NT) is an aggressive malignancy associated with Epstein-Barr virus infection, with a geographic and racial predilection for some Asian and Latin American countries. ENKTCL-NT manifests as a necrotic process affecting nasal or upper aerodigestive structures and, rarely, extranasal sites such as skin, and the gastrointestinal tract. ENKTCL-NT was characterized by its poor prognosis irrespective of clinical stage and therapy. However, during the last two decades, advances in its clinicopathologic, genetic and molecular characterization have been achieved, as have changes in the chemotherapy regimens that, in combination with radiotherapy, are significantly improving the survival of these patients, especially in initial stages. For these reasons, we present an overview of the historical background of ENKTCL-NT along with an updated review of its potential etiological factors, clinicopathologic and molecular features, as well as its prognostic models, current treatment protocols, and future directions on potential promising therapeutic approaches.

A five-year retrospective study of treatment outcomes using the L-asparaginase-based regimen as a first-line chemotherapy protocol for patients diagnosed with extranodal NK/T-cell lymphoma, nasal-type, in Thailand.

OBJECTIVE: To assess clinical outcomes of newly diagnosed extranodal NK/T-cell lymphoma nasal-type (ENKTL) patients treated with L-asparaginase-containing chemotherapy as first-line chemotherapy. MATERIALS AND METHODS: We retrospectively reviewed data of new ENKTL patients in Siriraj Hospital, Thailand during 2012-2016. RESULTS: Among 27 patients, 16 were men and 11 were women, and their median age was 52 (range, 25-83) years. The primary sites were the aero-nasal area (23) and skin (4). Clinical stages of ENKTL were I, II, III and IV in 10, 8, 1 and 8 patients, respectively. Patients classified according to the NK cell-lymphoma prognostic index with PINK (27) and PINK-E (19) as low, intermediate, and high were 14, 8, 5, respectively and 11, 4, and 4, respectively. Chemotherapy regimens used were SMILE (24) and AspaMetDex (3). Fourteen patients received post- chemotherapy local radiation. The overall response rate for 26 assessable patients was 69%, with complete response in 14 patients (52%). Median progression-free and overall survival were 32 and 33 months, respectively. The most common L-asparaginase regimen related complications were hypofibrinogenemia (24) and hypersensitivity (9). The overall mortality at follow-up was 14/27 (52%) owing to sepsis (11) and disease progression (3). DISCUSSION: L-asparaginase-based regimens showed similar results as other study results. including those in which hematopoietic stem cell transplantation was performed, suggesting that transplantation can be avoided if it is unaffordable. Thrombosis or bleeding, the regimen side effects, should be carefully monitored during treatment. CONCLUSIONS: L-asparaginase-based regimens offer a good outcome as a front-line treatment for ENKTL.

Management of NK/T-Cell Lymphoma, Nasal Type.

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, is a rare peripheral T-cell lymphoma associated with Epstein-Barr virus. It most often presents as limited-stage disease in patients of East Asian descent with a palatal deformity caused by erosion of the tumor through the hard palate. Limited-stage disease is often curable with the use of l-asparaginase-based chemotherapy and high-dose radiation therapy. Obtaining an accurate diagnosis is essential, because treatment with standard lymphoma regimens and omission of radiation severely compromise the likelihood of long-term survival. Conversely, patients with advanced disease have a poor prognosis and are recommended for asparaginase-based chemotherapy followed by consolidation with autologous transplantation as a potentially curative approach. Progress often has been hampered by the rarity of this disease. However, discovery of common genetic alterations in pathways that promote growth and inhibit apoptosis, and actionable markers such as CD30 (among others), have begun to broaden the availability of novel drugs (eg, targeted therapies). There is also cautious optimism about immunotherapies, such as checkpoint blockade and novel cellular therapies that target Epstein-Barr virus. Advances in treatment and understanding of the genetic landscape of this disease offer hope for improved treatment outcomes.

What we should know about natural killer/T-cell lymphomas.

Natural-killer/T cell lymphoma (NKTCL) is the most common extranodal lymphoma with highly aggressive clinical outcome. System biology techniques provide novel insights into the pathogenesis, risk stratification, and clinical management in NKTCL. Comparative genomic hybridization analysis reveal most frequent deletion of chromosome 6q21. Whole-exome sequencing studies identify recurrent somatic gene mutations, involving RNA helicases, tumor suppressors, JAK-STAT pathway molecules, and epigenetic modifiers. Genome-wide association study reports strongest association of HLA-DPB1 rs9277378 with lymphomagenesis. Alterations of oncogenic signaling pathways as well as epigenetic dysregulation of microRNA and long non-coding RNAs are also observed in NKTCL. Epstein-Barr virus (EBV) is the major etiology of NKTCL and the pathogenic mechanism remains unclear. Different risk stratification models are proposed based on clinical parameters (IPI, PINK, and PINK-E, etc.) or biomarkers (Ki67, C-reactive protein level, and EBV DNA, etc.). Therapeutic strategies vary according to disease stage, including radiotherapy, asparaginase-based chemotherapy, hematopoietic stem-cell transplantation, targeted therapy (immune checkpoints inhibitors, and histone deacetylation inhibitors, etc.). Future investigations will be emphasized on EBV-related pathogenesis of NKTCL, prognostic and therapeutic biomarkers, as well as multi-center clinical trials, so as to optimize personalized treatment of NKTCL in the era of precision medicine.

Extranodal NK/T-cell lymphoma in Tunisia: clinicopathological features, immunophenotype and EBV infection.

BACKGROUND: Extranodal NK/T-cell lymphomas (ENKTL) are rare non-Hodgkin's lymphomas with aggressive clinical behavior. ENKTL are frequently associated with the Epstein-Barr virus (EBV). Data on ENKTL in Africa and Arab world are extremely limited. The study investigated the clinicopathological characteristics, EBV infection, and immunophenotype of ENKTL in Tunisia. We conducted a retrospective study of ENKTL. Main clinicopathological features were reported. The expression of CD3, CD4, CD5, CD8, CD20, CD56, CD57, and Granzyme B were analyzed by immunohistochemistry. EBV infection was detected by IHC (LMP-1) and Epstein-Barr encoding region (EBER1/2) in situ hybridization. RESULTS: A total of nine ENKTL were identified (mean age of 48 years and male-to-female ratio of 8:1). There were five nasal ENKTL, and the remaining four cases had extranasal involvement (palate, sub-mandibular gland, skin, and soft tissues of the ankle). The histopathology showed a lymphoid and pleomorphic proliferation characterized by images of angiocentrism. Strong and diffuse CD3 expression was observed in all cases. Tumor cells exhibited an expression of CD5 (two cases), CD8 (three cases), CD56 (six cases), CD57 (three cases), and Granzyme B (eight cases). All ENKTL cases were EBV-associated. Overall 5-year survival rate was 57%. Although six ENKTL were diagnosed at early clinical stages, the prognosis was unfavorable and associated with patient death in three cases. CONCLUSIONS: ENKTL are exceptional in Tunisia with unfavorable outcome. Histopathological diagnosis remains challenging in clinical practice. However, a careful histopathological examination combined with a correct interpretation of immunohistochemistry and in situ hybridization results refines the ENKTL diagnosis.

Primary cutaneous lymphoma in Argentina: a report of a nationwide study of 416 patients.

BACKGROUND: The aim of this study was to determine the relative frequency of primary cutaneous lymphoma (PCL) in Argentina according to the new World Health Organization (WHO)-European Organization for the Research and Treatment of Cancer (EORTC) classification system. METHODS: A total of 416 patients from 21 dermatology services were included during a 5-year period (2010-2015); these patients were classified using WHO-EORTC criteria. RESULTS: There were 231 (55.2%) males and 185 (44.8%) females; the male-to-female ratio was 1.35. The median age of the patients was 57 years (range, 0-90 years). Most patients were Caucasian (79%), and only 16% of patients were registered as Amerindian. Most patients (387/416, 93%) had cutaneous T-cell lymphoma (CTCL); 28 patients (6.7%) were diagnosed with cutaneous B-cell lymphoma (CBCL). The most frequent CTCL subtypes, in decreasing order of prevalence, were mycosis fungoides (MF), including its variants (75.7%); CD30+ primary cutaneous lymphoproliferative disorders (7.2%); and Sézary syndrome (SS) (3.1%). Cutaneous follicle center lymphoma was the most common CBCL subtype (2.9%). In the subset of patients ≤20 years of age, the most common condition was MF (57%), followed by extranodal NK-T nasal-type lymphoma (14%). CONCLUSIONS: This study revealed relatively higher rates of MF and lower rates of CBCL in Argentinean patients that have been reported in American and European countries.

Extranodal lymphomas in the public health system in Chile: Analysis of 1251 patients from the National Adult Cancer Program.

The aim of the study was to describe the clinical and epidemiological characteristics, anatomic and histologic distribution, and treatment results of extranodal lymphomas (ENLs), diagnosed and treated in the public health system in Chile. We included patients with ENL diagnosed from 1998 to 2014, in 17 cancer centers, registered prospectively in the database of the National Adult Cancer Program (PANDA) of the Ministry of Health. Treatment was based on the local protocols for each lymphoma subtype. Extranodal lymphoma was documented in 1215 of 4907 non-Hodgkin lymphomas diagnosed in that period (25%). Median age was 59 years (range, 16-95), and 55% were female. The gastrointestinal (GI) tract was the most common location (38%), followed by the head and neck (24%) and the skin (15%). B-cell lymphomas accounted for 78% of cases, diffuse large B-cell lymphoma being the most common histologic subtype (68%). Mycosis fungoides/Sezary syndrome was the most frequent T-cell subtype (36%), followed by NK/T-cell lymphomanasal type (24%). In comparison with western countries, Chile showed a significantly high prevalence of NK/T-cell lymphoma nasal type, while the frequency of B-cell ENL and the anatomic distribution appeared similar, being GI the most commonly involved site.

Primary Nonanaplastic Peripheral Natural Killer/T-Cell Lymphoma in Pediatric Patients-An Unusual Distribution Pattern of Subtypes.

Peripheral NK/T-cell lymphoma (PNKTCL) represents a group of uncommon diagnoses for children in Western countries, and studies have often necessitated multiple institutions to assemble enough cases. We retrospectively analyzed 11 cases of nonanaplastic PNKTCL in children over 19 years at our institution with comparison to several published large multi-institutional studies. Patients included 9 males and 2 females of white (5), Native American (3), and Hispanic (3) background with 6 cases of extranodal NK/T-cell lymphoma, nasal type (EN-NKTL, 54.6%), 3 cases of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS, 27.2%), and 2 cases of systemic Epstein-Barr virus (EBV)-positive T-cell lymphoma of childhood (18.2%). Compared to the literature, our institution exceeded in frequency of total nonanaplastic PNKTCL (4.8% vs 0.9%-1.6%) with lesser relative incidence of PTCL-NOS (27.2% vs 42.9%-66.7%) and greater relative incidence of EN-NKTL (54.6% of cases vs 12.5%-47.6%), which significantly exceeded the literature's rate for Western institutions (13.5%). Potential influencing factors include population structure approximating those of non-Western countries with high EN-NKTL prevalence and the predisposition for EBV infection in this demography. These data suggest an uneven distribution of nonanaplastic PNKTCL in Western countries, and differential diagnoses may differ depending on practice location and associated patient population.

Genomic and transcriptomic landscapes of Epstein-Barr virus in extranodal natural killer T-cell lymphoma.

Extranodal natural killer T-cell lymphoma (nasal type; NKTCL) is an aggressive malignancy strongly associated with Epstein-Barr virus (EBV) infection. However, the role of EBV in NKTCL development is unclear, largely due to the lack of information about EBV genome and transcriptome in NKTCL. Here, using high-throughput sequencing, we obtained whole genome (n = 27) and transcriptome datasets (n = 18) of EBV derived from NKTCL tumor biopsies. We assembled 27 EBV genomes and detected an average of 1,152 single nucleotide variants and 44.8 indels (<50 bp) of EBV per sample. We also identified frequent focal EBV genome deletions and integrated EBV fragments in the host genome. Moreover, Phylogenetic analysis revealed that NKTCL-derived EBVs are closely clustered; transcriptome analysis revealed less activation of both latent and lytic genes and larger amount of T-cell epitope alterations in NKTCL, as compared with other EBV-associated cancers. Furthermore, we observed transcriptional defects of the BARTs miRNA by deletion, and the disruption of host NHEJ1 by integrated EBV fragment, implying novel pathogenic mechanisms of EBV. Taken together, we reported for the first time global mutational and transcriptional profiles of EBV in NKTCL clinical samples, revealing important somatic events of EBV and providing insights to better understanding of EBV's contribution in tumorigenesis.

Prognostic Nomogram for Overall Survival in Extranodal Natural Killer/T-Cell Lymphoma Patients.

BACKGROUND: Extranodal natural killer/T-cell lymphoma (ENKTL) is a rare lymphoid malignancy with diverse clinical features and prognoses. The aims of this study were to explore the pretreatment prognostic factors of ENKTL and develop a new individual prognostic model. PATIENTS AND METHODS: We retrospectively enrolled 81 ENKTL patients with newly diagnosed disease between June 2006 and August 2017 at the Affiliated Cancer Hospital of Guangxi Medical University. Survival analysis was used to assess the prognostic value of various factors. A nomogram was developed to predict overall survival (OS) based on the Cox proportional hazards model. RESULTS: The median survival time of the patients was 48 months, and the 5-year OS rate was 47.5%. Cox regression analysis showed that the prognostic factors of OS for ENKTL patients included Eastern Cooperative Oncology Group performance status, Ann Arbor stage, pretreatment albumin-to-globulin ratio, and platelet count. A prognostic nomogram was developed to predict the OS rate for ENKTL patients based on these factors. The calibration curve showed that the nomogram was able to predict OS accurately. The concordance index of the nomogram for OS prediction was 0.807. CONCLUSION: Our proposed nomogram based on Eastern Cooperative Oncology Group performance status, Ann Arbor stage, albumin-to-globulin ratio, and platelet count provides an individualized risk estimate of OS in patients with ENKTL.

Extranodal NK/T-cell lymphoma, nasal type: Clinical features, outcome, and prognostic factors in 101 cases.

OBJECTIVES: We aimed to define the clinical features, outcome, and prognostic factors for extranodal NK/T-cell lymphoma (ENKTL) patients in Taiwan. METHODS: We retrospectively reviewed 101 ENKTL patients diagnosed between February 1998 and October 2015. RESULTS: The median age of 101 patients was 52 years old (range 22-85); 76.2% of patients were Ann Arbor stage I/II disease. The 5-year progression-free survival (PFS) and overall survival (OS) were 49.9% and 54.8%, respectively. Patients with log[EBV-DNA] ≥ 3.8 and bone marrow hemophagocytosis at diagnosis had inferior PFS and OS. Most stage I/II patients received combined chemoradiotherapy with anthracycline-containing regimen, with overall response rate of 96.7%, complete response rate 86.9%, 5-year PFS 65%, and OS 72%. The relapse rate was 29.3% with a short median disease-free survival of 6.2 months. In advanced stage patients, overall response rate was only 13.6%, with median PFS 2.3 months, and OS 4.8 months. Age ≥ 60 (HR 3.773, 95% CI 1.733-8.215, P = 0.001) and stage III/IV (HR 7.785, 95% CI 2.312-26.213, P = 0.001) were unfavorable prognostic factors for PFS and OS by multivariate analyses. CONCLUSIONS: Age ≥ 60 and stage III/IV are independent poor prognostic factors for PFS and OS. Early-stage ENKTL patients had good response to combined chemoradiotherapy with anthracycline-containing regimen but with a high relapse rate and short disease-free survival. Anthracycline-containing regimen in advanced stage had poor response and dismal outcome.

Natural Killer/T-cell Neoplasms: Analysis of Incidence, Patient Characteristics, and Survival Outcomes in the United States.

BACKGROUND: Limited data are available regarding the incidence, survival patterns, and long-term outcomes of natural killer (NK)/T-cell neoplasms in the United States. PATIENTS AND METHODS: We performed a retrospective study of patients with NK/T-cell neoplasms diagnosed from 2001 to 2014 using the Surveillance, Epidemiology, and End Results program database. The Kaplan-Meier method was used to estimate the overall survival difference among the subgroups. Multivariate analyses were used to determine the factors affecting survival. RESULTS: For the 797 patients with NK/T-cell lymphoma, nasal type, the median age at diagnosis was 53 years, and males tended to be younger at diagnosis (P < .0001). The incidence of the disease increased from 0.4 in 2001 to 0.8 in 2014 per 1,000,000 individuals. The incidence was significantly greater in Hispanic patients compared with that in non-Hispanic patients (rate ratio, 3.03; P = .0001). The median overall survival was 20 months (range, 2-73 months) and varied significantly according to the primary site (P < .0001) and the disease stage at diagnosis (P < .0001). NK/T-cell lymphoma patients had an increased risk of acute myeloid leukemia (standardized incidence ratio, 18.77; 95% confidence interval, 2.27-67.81). For the 105 NK/T-cell leukemia patients, the median age at diagnosis was 58 years (range, 4-95 years). The overall incidence of the disease was 0.09 per 1,000,000 individuals and was significantly greater in males (rate ratio, 0.41; P < .0001). Unlike NK/T-cell lymphoma, no racial disparities were found in the incidence. The median overall survival was 17 months (range, 0-36 months). CONCLUSION: The incidence of NK/T-cell lymphoma, nasal type, in the United States has at least doubled in the past decade, with the greatest predilection among Hispanics. Patients with NK/T-cell lymphoma might have an increased risk of the subsequent development of acute myeloid leukemia.

Distribution of lymphoid neoplasms in Northwest China: Analysis of 3244 cases according to WHO classification in a single institution.

To explore the distribution of lymphoid neoplasms in Northwest China, the clinical and pathological data of lymphoma patients from 2006 to 2014 were analyzed according to the WHO classification in Xijing Hospital. Of the 3244 cases, mature B-cell neoplasms occupied 60.7%, while mature T/NK-cell neoplasms and Hodgkin's lymphomas (HL) occupied 26.2% and 8.1%, respectively. The most common subtype of lymphoma was diffuse large B-cell lymphoma (35.0%), followed by extranodal NK/T-cell lymphoma, nasal type (ENKTCL) (12.9%) and marginal zone B-cell lymphoma (7.8%). Mixed cellularity (34.0%) was the most common subtype of HL. The especially high proportion of ENKTCL was the most outstanding feature of our study in comparison to previous reports. The mean age of all lymphoid neoplasms cases was 51years and most subtypes showed male predominance, with an average male-female ratio of 1.6. Extranodal lymphomas took up about 60% of all cases and gastrointestinal tract was the most frequently involved site. In conclusion, the distribution of lymphoid neoplasms of Northwest China showed some features similar to previous reports of China and other countries, but some subtypes presented distinct features.