Prognostic factors for mature natural killer (NK) cell neoplasms: aggressive NK cell leukemia and extranodal NK cell lymphoma, nasal type

Prognostic Value of 18F-FDG PET/CT Radiomics in Extranodal Nasal-Type NK/T Cell Lymphoma

OBJECTIVE

To investigate the prognostic utility of radiomics features extracted from 18F-fluorodeoxyglucose (FDG) PET/CT combined with clinical factors and metabolic parameters in predicting progression-free survival (PFS) and overall survival (OS) in individuals diagnosed with extranodal nasal-type NK/T cell lymphoma (ENKTCL).

MATERIALS AND METHODS

A total of 126 adults with ENKTCL who underwent 18F-FDG PET/CT examination before treatment were retrospectively included and randomly divided into training (n = 88) and validation cohorts (n = 38) at a ratio of 7:3. Least absolute shrinkage and selection operation Cox regression analysis was used to select the best radiomics features and calculate each patient's radiomics scores (RadPFS and RadOS). Kaplan-Meier curve and Log-rank test were used to compare survival between patient groups risk-stratified by the radiomics scores. Various models to predict PFS and OS were constructed, including clinical, metabolic, clinical + metabolic, and clinical + metabolic + radiomics models. The discriminative ability of each model was evaluated using Harrell's C index. The performance of each model in predicting PFS and OS for 1-, 3-, and 5-years was evaluated using the time-dependent receiver operating characteristic (ROC) curve.

RESULTS

Kaplan-Meier curve analysis demonstrated that the radiomics scores effectively identified high- and low-risk patients (all P < 0.05). Multivariable Cox analysis showed that the Ann Arbor stage, maximum standardized uptake value (SUVmax), and RadPFS were independent risk factors associated with PFS. Further, β2-microglobulin, Eastern Cooperative Oncology Group performance status score, SUVmax, and RadOS were independent risk factors for OS. The clinical + metabolic + radiomics model exhibited the greatest discriminative ability for both PFS (Harrell's C-index: 0.805 in the validation cohort) and OS (Harrell's C-index: 0.833 in the validation cohort). The time-dependent ROC analysis indicated that the clinical + metabolic + radiomics model had the best predictive performance.

CONCLUSION

The PET/CT-based clinical + metabolic + radiomics model can enhance prognostication among patients with ENKTCL and may be a non-invasive and efficient risk stratification tool for clinical practice.

Establishment of ganglioside GD2-expressing extranodal NK/T-cell lymphoma cell line with scRNA-seq analysis

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKL), is characterized by Epstein-Barr virus infection and poor prognosis. We established a novel cell line, ENKL-J1, from bone marrow cells of an ENKL patient. We found that ENKL-J1 cells express the ganglioside GD2 (GD2) and that GD2-directed chimeric antigen receptor T cells exhibit cytotoxicity against ENKL-J1 cells, indicating that GD2 would be a suitable target of GD2-expressing ENKL cells. Targeted next-generation sequencing revealed TP53 and TET2 variants in ENKL-J1 cells. Furthermore, single-cell RNA sequencing in ENKL-J1 cells showed high gene-expression levels in the oncogenic signaling pathways JAK-STAT, NF-κB, and MAPK. Genes related to multidrug resistance (ABCC1), tumor suppression (ATG5, CRYBG1, FOXO3, TP53, MGA), anti-apoptosis (BCL2, BCL2L1), immune checkpoints (CD274, CD47), and epigenetic regulation (DDX3X, EZH2, HDAC2/3) also were expressed at high levels. The molecular targeting agents eprenetapopt, tazemetostat, and vorinostat efficiently induced apoptosis in ENKL-J1 cells in vitro. Furthermore, GD2-directed chimeric antigen receptor T cells showed cytotoxicity against ENKL-J1 cells in vivo. These findings not only contribute to understanding the molecular and genomic characteristics of ENKL; they also suggest new treatment options for patients with advanced or relapsed ENKL.

Predictive model for treatment outcomes of peripheral T-cell lymphoma, not otherwise specified, in Taiwanese patients

PURPOSE

We aimed to explore the clinical outcomes and prognostic factors for PTCL-NOS patients in the real world.

METHODS

Clinical data were retrospectively collected from adult patients with PTCL-NOS treated at a single center in Taiwan.

RESULTS

104 PTCL-NOS patients with a median age of 53.0 years were enrolled. Patients with the International Prognostic Index (IPI) or prognostic index for peripheral T-cell lymphoma (PIT) scores of zero had a longer overall survival (OS) and progression free survival (PFS), while patients with IPI or PIT scores ≥1 did poorly. For patients who are eligible for transplantation, the use of pralatrexate as salvage chemotherapy has shown better OS (2-year OS 83.3% vs. 24.4%, P = 0.011) compared to patients who did not. By multivariate analysis, age >60 years, male, B symptoms, ECOG >1, lung involvement, and thrombocytopenia were independent adverse factors for OS. Incorporating factors in multivariate analysis, we established a novel predictive index for PTCL-NOS which efficiently stratifies patients into low (0-1 factor), intermediate-1 (2 factors), intermediate-2 (3 factors), and high risk (4-6 factors) groups with 2-year OS rates of 81.5%, 32.9%, 8.8%, and 0%, respectively (P < 0.001).

CONCLUSION

PTCL-NOS patients have a dismal prognosis in Taiwan. Novel agents may improve the outcomes of PTCL-NOS patients. The usefulness of the novel prognostic index for PTCL-NOS needs further validation.

Clinical features, prognostic stratification, and treatment of advanced-stage non-nasal type extranodal natural killer/T-cell lymphoma: a multi-institutional real-world study

The present study aimed to investigate the clinical features, prognosis, and treatment of advanced-stage non-nasal type extranodal natural killer/T-cell lymphoma (ENKTCL). This real-world study retrospectively reviewed 56 newly diagnosed advanced-stage non-nasal type ENKTCL patients from two large-scale Chinese cancer centers in the last 10-15 years and screened 139 newly diagnosed advanced-stage nasal type ENKTCLs admitted during the same period for comparison. The non-nasal type ENKTCLs exhibited significantly higher Ki-67 expression levels compared to nasal type disease (P = 0.011). With a median follow-up duration of 75.03 months, the non-nasal group showed slightly inferior survival outcomes without statistically significant differences compared to the nasal group (median overall survival (OS): 14.57 vs. 21.53 months, 5-year OS: 28.0% vs. 38.5%, P = 0.120). Eastern Cooperative Oncology Group (ECOG) score ≥ 2 (hazard ratio (HR) = 2.18, P = 0.039) and lactic dehydrogenase (LDH) elevation (HR = 2.44, P = 0.012) were significantly correlated with worse OS in the non-nasal group. First-line gemcitabine-based chemotherapy regimens showed a trend toward slightly improved efficacy and survival outcomes compared to non-gemcitabine-based ones in the present cohort of non-nasal ENKTCLs (objective response rate: 91.7% vs. 63.6%, P = 0.144; complete response rate: 50.0% vs. 33.3%, P = 0.502; median progression-free survival: 10.43 vs. 3.40 months, P = 0.106; median OS: 25.13 vs. 9.30 months, P = 0.125), which requires further validation in larger sample size studies. Advanced-stage non-nasal type patients could achieve comparable prognosis with nasal cases after rational therapy. The modified nomogram-revised index (including age, ECOG score, and LDH) and modified international prognostic index (including age, ECOG score, LDH, and number of extranodal involvement) functioned effectively for prognostic stratification in non-nasal type ENKTCLs.

Extranodal NK/T-cell lymphoma with localized relapse in bone marrow of lower leg detected using PET-CT

Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is a rare subtype of non-Hodgkin lymphoma (NHL) with poor prognosis, particularly in relapsed or refractory patients. Thus, timely detection of relapse and appropriate disease management are crucial. We present two patients with ENKTL, wherein positron emission tomography-computed tomography (PET-CT) with total-body coverage after induction therapy, detected newly relapsed regions in the bone marrow of the lower leg prior to progression. Case 1: A 47-year-old woman with nasal obstruction, showing 18F-fluoro-deoxyglucose (FDG) uptake in the nasal cavity (Lugano stage IE). After induction therapy (RT-2/3 DeVIC), PET-CT revealed abnormal uptake only in the right fibula. Case 2: A 68-year-old man with a skin nodule/ulcer and an enlarged right inguinal lymph node was diagnosed with advanced ENKTL. A PET-CT scan revealed abnormal uptake in the subcutaneous mass of the right medial thigh, lymph nodes, and descending colon (Lugano stage IV). After induction therapy, PET-CT revealed new abnormal uptake only in the left tibia. In both patients, CT-guided biopsy confirmed ENKTL recurrence. Moreover, PET-CT with whole-body coverage was useful for the timely assessment of relapse and detection of asymptomatic bone involvement. This approach allowed for modifications to treatment strategies in certain patients.

Molecular and clinicopathological features of granzyme B-negative extranodal NK/T-cell lymphoma

Extranodal NK/T-cell lymphoma (ENKTL) generally expresses cytotoxic molecules, including granzyme B (GZMB), T-cell-restricted intracellular antigen-1 (TIA-1), and perforin; however, the expression of these molecules varies across cases. We performed gene expression profiling and identified unique biological and clinicopathological features of GZMB-negative ENKTL. We reviewed the clinicopathological characteristics of 71 ENKTL samples. Gene expression profiling on nine ENKTLs using multiplexed, direct, and digital mRNA quantification divided ENKTLs into Groups A (n = 7) and B (n = 2) through hierarchical clustering and t-distributed stochastic neighbor embedding. Group B was characterized by downregulation of genes associated with IL6-JAK-STAT3 signaling and inflammatory responses. GZMB mRNA expression was significantly downregulated in Group B. GZMB protein expression was evaluated with immunohistochemistry in all 71 ENKTLs, and expression data of Tyr705-phosphorylated STAT3 (pSTAT3) and MYC from our previous study was utilized. T-cell receptor gamma (TRG) gene rearrangement in the selected samples was also assessed using PCR. GZMB expression was higher in pSTAT3-positive (p = 0.028) and MYC-positive (p = 0.014) ENKTLs. Eighteen percent (13/71) of all ENKTLs were negative for GZMB (defined by positivity <10 %); patients with GZMB-negative ENKTLs were often in a higher clinical stage (p = 0.016). We observed no other correlations with clinical parameters or TRG rearrangement and no significant association between GZMB expression and survival. In conclusion, GZMB expression is highly heterogeneous in ENKTLs and is associated with the activation of the JAK-STAT3 pathway and higher MYC expression. GZMB-negative ENKTLs correlate with an advanced clinical stage, suggesting the potential utility of GZMB immunohistochemistry as a biomarker of ENKTL.

Extranodal natural killer/T-cell lymphoma coexisting with peripheral T-cell lymphoma, not otherwise specified

We report the case of a 52-year-old male who presented to our hospital with cervical lymphadenopathy. Lymph node biopsy revealed small atypical lymphoid cells positive for CD3 and CD5 and negative for CD56 and Epstein-Barr virus (EBV)-encoded small RNA (EBER) by in situ hybridization. CD4-positive cells and CD8-positive cells were mixed in almost equal numbers. He was diagnosed with peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS). The patient received one cycle of chemotherapy, resulting in severe sepsis. While undergoing treatment in the intensive care unit with an antimicrobial agent and prednisone, ascitic fluid appeared. Abdominal aspiration revealed neutrophil-predominant ascites and microbiological studies revealed Candida albicans. However, ascites did not improve when treated with micafungin for Candida peritonitis. Abdominal aspiration was re-performed, and atypical lymphoid cells that were positive for CD3 and CD56 were detected. EBV-DNA levels in whole blood were significantly elevated. Atypical lymphoid cells were positive for EBER by in situ hybridization and Southern blot analysis showed EBV terminal repeat monoclonal patterns. Bone marrow examination revealed the same atypical lymphoid cells. Therefore, the patient was diagnosed with extranodal natural killer/T-cell lymphoma (ENKTL) with bone marrow involvement 3 months after the diagnosis of PTCL-NOS. Complications associated with PTCL-NOS and ENKTL are rare. PTCL-NOS, chemotherapy, sepsis, and prednisone might have led to immunodeficiency and reactivation of EBV, which might be one of the pathophysiologies for developing ENKTL. Our case indicates that measuring EBV-DNA in the blood is a simple and prompt examination to detect complications of EBV-associated lymphoma.

Single-Cell Analysis Reveals Malignant Cells Reshape the Cellular Landscape and Foster an Immunosuppressive Microenvironment of Extranodal NK/T-Cell Lymphoma

Extranodal natural killer/T-cell lymphoma (NKTCL) is an aggressive type of lymphoma associated with Epstein-Barr virus (EBV) and characterized by heterogeneous tumor behaviors. To better understand the origins of the heterogeneity, this study utilizes single-cell RNA sequencing (scRNA-seq) analysis to profile the tumor microenvironment (TME) of NKTCL at the single-cell level. Together with in vitro and in vivo models, the study identifies a subset of LMP1+ malignant NK cells contributing to the tumorigenesis and development of heterogeneous malignant cells in NKTCL. Furthermore, malignant NK cells interact with various immunocytes via chemokines and their receptors, secrete substantial DPP4 that impairs the chemotaxis of immunocytes and regulates their infiltration. They also exhibit an immunosuppressive effect on T cells, which is further boosted by LMP1. Moreover, high transcription of EBV-encoded genes and low infiltration of tumor-associated macrophages (TAMs) are favorable prognostic indicators for NKTCL in multiple patient cohorts. This study for the first time deciphers the heterogeneous composition of NKTCL TME at single-cell resolution, highlighting the crucial role of malignant NK cells with EBV-encoded LMP1 in reshaping the cellular landscape and fostering an immunosuppressive microenvironment. These findings provide insights into understanding the pathogenic mechanisms of NKTCL and developing novel therapeutic strategies against NKTCL.

Extranodal NK/T-Cell Lymphoma, Nasal Type, Extranasal and Ulcerative Blister Variant, Case Report

The extranodal natural killer (NK) T-cell lymphoma of nasal type is a form of lymphoma that falls within the WHO/EORTC 2018 classification of cutaneous T-cell lymphomas. It is characterized for being aggressive, infrequent, and destroying midline facial structures; however, it can also be in primary or secondary form at extranasal sites, such as the skin or the gastrointestinal tract, among others. We report the case of an 18-year-old patient with an extranodal NK/T-cell lymphoma located in an extranasal site. The clinical presentation is characterized for being multifocal and with erythematous-violaceous plaques that progress to hemorrhagic blisters and necrotic ulcers. Although this type of lymphoma has been reported previously by others, the presence of blisters is an atypical finding, which we believe has been described only in one case in the medical literature.

Discovery and biological evaluation of a potent small molecule CRM1 inhibitor for its selective ablation of extranodal NK/T cell lymphoma

Background

The overactivation of NF-κB signaling is a key hallmark for the pathogenesis of extranodal natural killer/T cell lymphoma (ENKTL), a very aggressive subtype of non-Hodgkin's lymphoma yet with rather limited control strategies. Previously, we found that the dysregulated exportin-1 (also known as CRM1) is mainly responsible for tumor cells to evade apoptosis and promote tumor-associated pathways such as NF-κB signaling.

Methods

Herein we reported the discovery and biological evaluation of a potent small molecule CRM1 inhibitor, LFS-1107. We validated that CRM1 is a major cellular target of LFS-1107 by biolayer interferometry assay (BLI) and the knockdown of CRM1 conferred tumor cells with resistance to LFS-1107.

Results

We found that LFS-1107 can strongly suppresses the growth of ENKTL cells at low-range nanomolar concentration yet with minimal effects on human platelets and healthy peripheral blood mononuclear cells. Treatment of ENKTL cells with LFS-1107 resulted in the nuclear retention of IkBα and consequent strong suppression of NF-κB transcriptional activities, NF-κB target genes downregulation and attenuated tumor cell growth and proliferation. Furthermore, LFS-1107 exhibited potent activities when administered to immunodeficient mice engrafted with human ENKTL cells.

Conclusions

Therefore, LFS-1107 holds great promise for the treatment of ENKTL and may warrant translation for use in clinical trials.

Funding

Yang's laboratory was supported by the National Natural Science Foundation of China (Grant: 81874301), the Fundamental Research Funds for Central University (Grant: DUT22YG122) and the Key Research project of 'be Recruited and be in Command' in Liaoning Province (Personal Target Discovery for Metabolic Diseases).

Newly diagnosed extranodal NK/T-cell lymphoma, nasal type, at the injected left arm after BNT162b2 mRNA COVID-19 vaccination

Anti-SARS-CoV-2 vaccines were developed in response to the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although the BNT162b2 mRNA vaccine is effective, adverse effects have been reported. Here, we report a case of extranodal NK/T-cell lymphoma, nasal type (ENKL), of the left arm following BNT162b2 mRNA vaccination. A 73-year-old male presented with a lump in the left arm, which was the site where he received the BNT162b2 mRNA vaccine 3 months prior. He was treated with topical corticosteroids and debridement, but the tumor progressed. Additionally, fever, night sweats, and general fatigue were observed. Laboratory findings included thrombocytopenia, elevated lactate dehydrogenase, and soluble interleukin-2 receptor levels. Skin biopsy led to a diagnosis of ENKL. The patient was treated with a 50% dose of SMILE therapy and radiotherapy, resulting in regression of the tumor. It seems that latent Epstein-Barr virus (EBV)-infected NK/T cells were reactivated by vaccination and contributed to the onset of ENKL. This is the first report of ENKL after BNT162b2 mRNA vaccination. The present case highlights the possible risk of development of malignant lymphoma, including ENKL at the injection site, after BNT162b2 COVID-19 vaccination.

NK/T-cell Lymphoma With Orbital Involvement: A Case Report and Systematic Review of the Literature

PURPOSE

To present the clinical course of a patient with recurrent NK/T-cell lymphoma (NKTL) involving the orbit and to review the literature on patients with NKTL involving the orbit.

METHODS

The PubMed database was searched for all cases of NKTL involving orbital, intraocular, or adnexal ocular structures.

RESULTS

Ninety-six patients were included in the final analysis. The mean age of diagnosis was 48.1 ± 16.8 years. The patients were 53/96 (55.2%) male and 43/96 (44.8%) female. Tumor location varied and included the orbit in 80/96 (83.3%), nasosinus in 56/96 (58.3%), uvea in 11/96 (11.5%), lacrimal gland in 9/96 (9.4%), lacrimal drainage system in 11/96 (11.5%), and conjunctiva in 7/96 (7.3%) cases. Management included surgical debulking in 29/96 (30.2%) cases, radiotherapy in 52/96 (54.2%) cases, and chemotherapy in 82/96 (85.4%) cases. Median survival was 6 months (95% CI: 5-9). Chemotherapy (hazard ratio = 0.80, 95% CI: 0.67-0.95, p = 0.013), radiotherapy (hazard ratio = 0.75, 95% CI: 0.64-0.87, p < 0.001), and orbital involvement being a recurrence of disease (hazard ratio = 0.79, 95% CI: 0.67-0.95, p = 0.009) were associated with improved survival. Advanced Ann Arbor stage (III-IV) at diagnosis (hazard ratio = 1.22, 95% CI: 1.08-1.38, p = 0.001), vision loss (hazard ratio = 1.18, 95% CI: 1.04-1.34, p = 0.009), proptosis (hazard ratio = 1.15, 95% CI: 1.01-1.30, p = 0.035) and periorbital swelling (hazard ratio = 1.15, 95% CI: 1.00-1.33, p = 0.048) were associated with poor survival.

CONCLUSIONS

NK/T-cell lymphoma involving the orbit, globe, or ocular adnexa heralds a poor prognosis where early diagnosis and therapy are critical. The use of radiotherapy and chemotherapy is associated with improved survival.

Multimodality imaging evaluation of primary testicular extranodal natural killer/T-cell lymphoma: two case reports

Background

Extranodal natural killer/T-cell lymphoma (ENKTCL) is a distinct pathological entity and accounts for ~10% of T-cell lymphomas. The histological features of ENKTCL include angiodestruction and coagulative necrosis and the association with EBV infection. ENKTCL is typically aggressive and mainly affects the nasal cavity and nasopharyngeal region. However, some patients can present with distant nodal or extranodal involvement such as the Waldeyer ring, gastrointestinal tract, genitourinary organs, lung, thyroid, skin, and testes. Compared to ENKTCL of nasal type, primary testicular ENKTCL is very rare and has a lower age of onset and faster clinical progression, with tumor cell dissemination occurring early in the disease.

Case report

Case 1: A 23-year-old man presented with 1 month of right testicular pain and swelling. Enhancement CT revealed increased density in the right testis, uneven increased enhancement, discontinuity of the local envelope, and multiple trophoblastic vessels in the arterial phase. Testicular ENKTCL was diagnosed by post-operative pathology. The patient underwent a follow-up ¹⁸F-FDG PET/CT imaging 1 month later and found elevated metabolism in the bilateral nasal, left testicular, and right inguinal lymph nodes. Unfortunately, the patient received no further treatment and died 6 months later. Case 2: A 2-year-old male child presented with an enlarged right testicle, MRI showed a mass in the right epididymis and testicular area, which showed low signal on T1WI, high signal on T2WI and DWI, and low signal on ADC. Meanwhile, CT showed soft tissue in the lower lobe of the left lung and multiple high-density nodules of varying sizes in both lungs. Based on the post-operative pathology, the lesion was diagnosed with primary testicular ENKTCL. The pulmonary lesion was diagnosed as hemophagocytic lymphohistiocytosis associated with EBV infection. The child was given SMILE chemotherapy, but pancreatitis was induced during chemotherapy, then he died 5 months later after chemotherapy.

Conclusion

Primary testicular ENKTCL is very rare in clinical practice, typically presenting as a painful testicular mass, which can mimic inflammatory lesions and cause diagnostic challenges. ¹⁸F-FDG PET/CT plays pivotal roles in the diagnosis, staging, evaluation of treatment outcomes and prognosis evaluation in patients with testicular ENKTCL, and it is helpful to assist clinical practice to better formulate individualized treatment plans.

Aggressive Cutaneous Lymphomas and Their Mimics

Cutaneous lymphomas encompass a heterogeneous group of neoplasms with a wide spectrum of clinical presentations, histopathologic features, and prognosis. Because there are overlapping pathologic features among indolent and aggressive forms and with systemic lymphomas that involve the skin, clinicopathologic correlation is essential. Herein, the clinical and histopathologic features of aggressive cutaneous B- and T-cell lymphomas are reviewed. Indolent cutaneous lymphomas/lymphoproliferative disorders, systemic lymphomas, and reactive processes that may mimic these entities are also discussed. This article highlights distinctive clinical and histopathologic features, increases awareness of rare entities, and presents new and evolving developments in the field.

Diagnostic performance and prognostic value of circulating tumor DNA methylation marker in extranodal natural killer/T cell lymphoma

Circulating tumor DNA (ctDNA) carries tumor-specific genetic and epigenetic variations. To identify extranodal natural killer/T cell lymphoma (ENKTL)-specific methylation markers and establish a diagnostic and prognosis prediction model for ENKTL, we describe the ENKTL-specific ctDNA methylation patterns by analyzing the methylation profiles of ENKTL plasma samples. We construct a diagnostic prediction model based on ctDNA methylation markers with both high specificity and sensitivity and close relevance to tumor staging and therapeutic response. Subsequently, we built a prognostic prediction model showing excellent performance, and its predictive accuracy is significantly better than the Ann Arbor staging and prognostic index of natural killer lymphoma (PINK) risk system. Notably, we further establish a PINK-C risk grading system to select individualized treatment for patients with different prognostic risks. In conclusion, these results suggest that ctDNA methylation markers are of great value in diagnosis, monitoring, and prognosis, which might have implications for clinical decision-making of patients with ENKTL.

Demographic and treatment risk factors of cancer-specific mortality among children and adolescent leukemia patients: a population-based study

Leukemia is the 15th most commonly diagnosed cancer and the 11th leading cause of cancer mortality. The high mortality rate of leukemia could be attributed to numerous factors. Therefore, we aimed to identify the demographic and treatment risk factors influencing mortality among patients diagnosed with leukemia. Patients' data from 1975 to 2016 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. We used the Person's chi-square test to examine the associations among the categorical variables. Kaplan-Meier and Cox regression were applied for univariate and multivariate analyses. Standardized mortality ratios were utilized to compare the mortality rates of leukemia patients and the general US population. We carried out the statistical analysis using SPSS software. A total of 18,880 patients with leukemia were studied. The leukemia incidence was increased in children than in adolescents. Acute lymphoid leukemia (ALL) was the most common type diagnosed among children and adolescents: 10,331 and 4112 patients, respectively. All mortality ratios were significantly higher in leukemia patients compared to the US population. The risk of mortality among leukemia patients was higher among adolescents, females, Black, urban areas with a 20,000 population, and patients not receiving chemotherapy. In contrast, the mortality risk was decreased in patients with higher family incomes, those not treated with radiation, and diagnosed from 2000 to 2016. In conclusion, Leukemia's incidence increases with time. Adolescents, males, Black, in some urban areas, and patients who have not received chemotherapy had the highest mortality risk among leukemia patients.

Long-Term Outcomes of Definitive Chemoradiotherapy for Early-Stage Extranodal Natural Killer/T-cell Lymphoma, Nasal Type: A Retrospective Analysis From a Single Center

Background Nasal extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is a rare type of lymphoma with characteristic histological features. Although radiotherapy can achieve a high response rate, long-term efficacy and safety are yet to be established. Methodology Using electronic health records, we identified relevant patients treated at our hospital from August 2005 to August 2015. We enrolled patients with pathologically confirmed ENKTL treated with curative intent radiotherapy. Results We included 13 patients who underwent definitive radiotherapy in the analysis, comprising 11 males and 2 females and a median age of 53 years (range: 28-73). The median follow-up period was 113.4 months. The overall survival at 5 and 10 years was 92.3% (95% confidence interval [CI]: 57-99 %) and 68.4% (95% CI: 29-89 %), respectively. The most common radiation-related late-term toxicity was sinus disorder (Grade 1-2) in 11 patients (85%). Radiation-related grade 3 to 5 toxicities were not observed. Conclusion The present retrospective study elucidated the long-term safety and effectiveness of curative intent radiotherapy in patients with localized ENKTL.

Sinonasal lymphoma: A primer for otolaryngologists

Objective

Sinonasal lymphomas are a rare entity that commonly present with nonspecific sinonasal symptoms and are often recognized immediately. Through this review, we aim to summarize important principles in diagnosis and treatment of sinonasal lymphomas, with the goal of disseminating the current knowledge of this under-recognized malignancy to otolaryngologists.

Methods

Systemic review using PRISMA guidelines of foundational scholarly articles, guidelines, and trials were reviewed focusing on clinical characteristics of key sinonasal lymphoma subtypes, along with available treatments in the otolaryngology, medical oncology, and radiation oncology literature.

Results

Sinonasal lymphoma are derived from clonal proliferation of lymphocytes at various stages of differentiation, of which diffuse large B-cell lymphoma (DLBCL) and extranodal natural killer/T-cell lymphoma (ENKTL) are the most common. Diagnosis and staging require biopsy with immunohistochemistry in conjunction with imaging and laboratory studies. Treatment is ever evolving and currently includes multi-agent chemotherapy and/or radiation therapy.

Conclusion

Otolaryngologists may be the first to recognize sinonasal lymphoma, which requires a comprehensive workup and a multidisciplinary team for treatment. Symptoms are nonspecific and similar to many sinonasal pathologies, and it is crucial for otolaryngologists to keep a broad differential.

Level of Evidence

5.

Cellular Origins and Pathogenesis of Gastrointestinal NK- and T-Cell Lymphoproliferative Disorders

The intestinal immune system, which must ensure appropriate immune responses to both pathogens and commensal microflora, comprises innate lymphoid cells and various T-cell subsets, including intra-epithelial lymphocytes (IELs). An example of innate lymphoid cells is natural killer cells, which may be classified into tissue-resident, CD56bright NK-cells that serve a regulatory function and more mature, circulating CD56dim NK-cells with effector cytolytic properties. CD56bright NK-cells in the gastrointestinal tract give rise to indolent NK-cell enteropathy and lymphomatoid gastropathy, as well as the aggressive extranodal NK/T cell lymphoma, the latter following activation by EBV infection and neoplastic transformation. Conventional CD4+ TCRαβ+ and CD8αβ+ TCRαβ+ T-cells are located in the lamina propria and the intraepithelial compartment of intestinal mucosa as type 'a' IELs. They are the putative cells of origin for CD4+ and CD8+ indolent T-cell lymphoproliferative disorders of the gastrointestinal tract and intestinal T-cell lymphoma, NOS. In addition to such conventional T-cells, there are non-conventional T-cells in the intra-epithelial compartment that express CD8αα and innate lymphoid cells that lack TCRs. The central feature of type 'b' IELs is the expression of CD8αα homodimers, seen in monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), which primarily arises from both CD8αα+ TCRαβ+ and CD8αα+ TCRγδ+ IELs. EATL is the other epitheliotropic T-cell lymphoma in the GI tract, a subset of which arises from the expansion and reprograming of intracytoplasmic CD3+ innate lymphoid cells, driven by IL15 and mutations of the JAK-STAT pathway.

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.

Induction with MEDA regimen and consolidation with Auto-HSCT for stage IV NKTCL patients: a prospective multicenter study

Optimal treatment strategies for natural killer/T-cell lymphoma (NKTCL) patients with stage IV disease have not been well defined. In this prospective phase 2 study, we evaluated the treatment using MEDA (methotrexate, etoposide, dexamethasone, and pegaspargase) as induction chemotherapy and autologous hematopoietic stem cell transplantation (Auto-HSCT) for consolidation. Patients with stage IV disease without prior L-asparaginase-based chemotherapy were eligible. Four cycles of MEDA were administered as induction treatment. Patients with complete response (CR, necessary to have complete metabolic remission of PET/CT, negative plasma EBV-DNA, and negative EBER staining of bone marrow biopsy tissue) were consolidated by Auto-HSCT. A total of 53 patients were enrolled. The overall response (OR) rate and CR rate after four cycles of MEDA chemotherapy were 75.5% and 56.6%, respectively. Among them, 25 patients underwent Auto-HSCT. The 4-year overall survival (OS) rate and progression-free survival (PFS) rate were 58.0% (95%CI, 43.4% to 70.0%) and 43.4% (95% CI, 29.9% to 56.1%), respectively. Patients who underwent Auto-HSCT had a 4-year OS rate of 92.0% (95% CI, 71.6% to 97.9%) and a 4-year PFS rate of 80.0% (95% CI, 58.4% to 91.1%). Grade 3/4 neutropenia and thrombocytopenia occurred in 28.3% and 17.0% of the patients, respectively. MEDA chemotherapy is an effective induction regimen with reduced grade 3/4 hematological toxicities for stage IV NKTCL. Consolidation with Auto-HSCT can be considered as a potential approach to improve the long-term survival of CR patients after induction treatment. This article is protected by copyright. All rights reserved.

EBV associated T- and NK-cell lymphoproliferative diseases: A comprehensive overview of clinical manifestations and novel therapeutic insights

EBV is a ubiquitous virus that infects nearly all people around the world. Most infected people are asymptomatic and do not show serious sequelae, while others may develop Epstein-Barr virus (EBV)-positive T and NK-cell lymphoproliferations characterised by EBV-infected T or NK cells. These disorders are more common in Asian and Latin American people, suggesting genetic predisposition as a contributing factor. The revised WHO classification classifies the lymphoproliferative diseases as: extranodal NK/T-cell lymphoma nasal type (ENKTL), aggressive NK-cell leukemia (ANKL), primary EBV-positive nodal T or NK cell lymphoma (NNKTL), systemic EBV-positive T-cell lymphoproliferative disease of childhood (STCLC), systemic chronic active EBV infection (sys CAEBV), hydroa-vacciniforme (HV) and severe mosquito bite allergy (SMBA). Recent advances in the molecular pathogenesis of these diseases have led to the development of new therapeutic strategies. Due to the infrequency of the diseases and broad clinicopathological overlap, the diagnosis and classification are challenging for both clinicians and pathologists. In this article, we aim to review the recent pathological findings which can be helpful for designing new drugs, clinical presentations and differential diagnoses, and suggested therapeutic interventions to provide a better understanding of these rare disorders.

The Pathologic and Genetic Characteristics of Extranodal NK/T-Cell Lymphoma

Extranodal NK/T-cell lymphoma is a neoplasm of NK cells or cytotoxic T cells presenting in extranodal sites, most often in the nasal cavity. The typical immunophenotypes are cCD3+, sCD3-, CD4-, CD5-, CD8-, CD16-, and CD56+ with the expression of cytotoxic molecules. Tumor subsets express NK cell receptors, CD95/CD95L, CD30, MYC, and PDL1. Virtually all the tumor cells harbor the EBV genome, which plays a key role in lymphomagenesis as an epigenetic driver. EBV-encoded oncoproteins modulate the host-cell epigenetic machinery, reprogramming the viral and host epigenomes using host epigenetic modifiers. NGS analysis revealed the mutational landscape of ENKTL, predominantly involving the JAK-STAT pathway, epigenetic modifications, the RNA helicase family, the RAS/MAP kinase pathway, and tumor suppressors, which indicate an important role of these pathways and this group of genes in the lymphomagenesis of ENKTL. Recently, three molecular subtypes were proposed, the tumor-suppressor/immune-modulator (TSIM), MGA-BRDT (MB), and HDAC9-EP300-ARID1A (HEA) subtypes, and they are well-correlated with the cell of origin, EBV pattern, genomic alterations, and clinical outcomes. A future investigation into the function and interaction of discovered genes would be very helpful for better understanding the molecular pathogenesis of ENKTL and establishing better treatment strategies.

Aggressive Natural Killer Cell Leukemia in an Adolescent Patient: A Case Report and Literature Review

Aggressive natural killer cell leukemia (ANKL) is a rare malignant tumor, especially uncommon in children. ANKL has very aggressive clinical course and bad prognosis and is usually caused by Epstein-Barr virus infection. ANKL often has clinical manifestations of hemophagocytic lymphohistiocytosis (HLH) and can be easily treated as HLH, which might complicate this aggressive disease. Here we report an ANKL in adolescent whose clinical presentation was highly aggressive and response to L-asparaginase containing chemotherapy was very bad. Early-onset Flow cytometry of peripheral blood and bone marrow help make the diagnosis.

Aggressive natural killer cell leukemia with skin manifestation associated with hemophagocytic lymphohistiocytosis: A case report

BACKGROUND

Aggressive natural killer cell leukemia (ANKL) is a rare natural killer cell neoplasm characterized by systemic infiltration of Epstein–Barr virus and rapidly progressive clinical course. ANKL can be accompanied with hemophagocytic lymphohistiocytosis (HLH). Here, we report a case of ANKL with rare skin lesions as an earlier manifestation, accompanied with HLH, and review the literature in terms of etiology, clinical manifestation, diagnosis and treatment.

CASE SUMMARY

A 30-year-old woman from Northwest China presented with the clinical characteristics of jaundice, fever, erythema, splenomegaly, progressive hemocytopenia, liver failure, quantities of abnormal cells in bone marrow, and associated HLH. The immunophenotypes of abnormal cells were positive for CD2, cCD3, CD7, CD56, CD38 and negative for sCD3, CD8 and CD117. The diagnosis of ANKL complicated with HLH was confirmed. Following the initial diagnosis and supplementary treatment, the patient received chemotherapy with VDLP regimen (vincristine, daunorubicin, L-asparaginase and prednisone). However, the patient had severe adverse reactions and complication such as severe hematochezia, neutropenia, and multiple organ dysfunction syndrome, and died a few days later.

CONCLUSION

This is the first reported case of ANKL with rare skin lesions as an earlier manifestation and associated with HLH.

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 clinicaldata from non-Asian countries are lacking. It is unclear whether outcomes and diseasenatural 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-diagnosedCD56 + ENKTL and studied disease characteristics and clinical outcomes.

RESULTS

121 patients with ENKTL diagnosed between June 1990 and November 2012 were identified. Eighty-three patients (69%) had stage I/II disease and were treatedwith combined modality therapy (CMT) (n=53), chemotherapy alone (CT) (n=14) orradiotherapy alone (RT) (n=16). Thirty-eight patients (31%) had stage III/IV diseaseand were treated with CMT (n=12), CT (n=23), or RT (n=3). The median follow-up forthe entire cohort was 51 months. Patients with stage I/II disease, compared to thosewith stage III/IV disease, had superior 2-year progression free survival (PFS) 43% vs19% (p=0.03) and overall survival (OS) 59% vs 29% (p=0.004). Outcomes were similarfor stage I/II patients who received CMT vs RT alone with 2-year PFS (53% vs 47%;p=0.91) and OS (67% vs 67%; p=0.58). No significant differences in outcomes werenoted 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.

What Effect Does Epstein-Barr Virus Have on Extranodal Natural Killer/T-Cell Lymphoma Prognosis? A Review of 153 Reported Cases

The primary aim of this review is to identify the relationship between Epstein-Barr virus (EBV) and prognosis in extranodal natural killer/T-cell lymphoma (ENKTL). Additionally, a literature review of ENKTL was carried out. The investigators designed and implemented a 21-year literature review using the online databases PubMed and Google Scholar. The total number of cases analyzed was 153 (64 case reports; one comparative study; one systematic review). Information related to ENKTL from July 1999 to February 2021 was included in the study. Study variables included: patient demographics, tumor classification, screening modalities, tumor characteristics, symptomatology, treatment, and prognosis. The average age at diagnosis was 50.9 years (range: 4-90 years). Patients of Asian ethnicity were most commonly affected, and there was a 1.6:1 male to female ratio. ENKTL was most frequently detected in the head and neck region, and 53.1% of cases metastasized. Of all head and neck cases, the nose was the most affected location. Immunohistochemistry positivity included: EBV (32.0%), CD2 (96.6%), CD3ϵ (81.7%), CD43 (91.7%), CD56 (86.4%), Granzyme (97.1%), Perforin (90.9%), TIA-1 (97.8%), p53 (33.3%). The most frequently employed single treatment modality was chemotherapy alone, and 34.2% of patients expired within five years of diagnosis. The average follow-up period was 16.51 months (range: 0.25-66 months). EBV was significantly associated with metastatic ENKTL (χ² = 4.36; CV = 3.84; p = 0.037). We found no association between EBV and ENKTL prognosis (χ² = 17.2; CV = 21.0; p = 0.14).

Extranodal NK/T-Cell Lymphoma, Nasal Type: Genetic, Biologic, and Clinical Aspects with a Central Focus on Epstein-Barr Virus Relation

Extranodal NK/T-Cell Lymphoma, nasal type (ENKTL-NT) has some salient aspects. The lymphoma is commonly seen in Eastern Asia, has progressive necrotic lesions in the nasal cavity, makes midfacial destructive lesions, and shows poor prognosis. The lymphoma cell is originated from either NK- or γδ T-cells, which express CD56. Since the authors first demonstrated the existence of Epstein–Barr virus (EBV) DNA and EBV oncogenic proteins in lymphoma cells, ENKTL-NT has been recognized as an EBV-associated malignancy. Because the angiocentric and polymorphous lymphoma cells are mixed with inflammatory cells on a necrotic background, the diagnosis of ENKTL-NT requires CD56 immunostaining and EBER in situ hybridization. In addition, serum the EBV DNA level is useful for the diagnosis and monitoring of ENKTL-NT. Although ENKTL-NT is refractory lymphoma, the prognosis is improved by the development of therapies such as concomitant chemoradiotherapy. The basic research reveals that a wide variety of intracellular/cell surface molecules, cytokines, chemokines, and micro RNAs are involved in lymphomagenesis, and some of them are related to EBV. Understanding lymphoma behavior introduces new therapeutic strategies, such as the usage of immune checkpoint inhibitors, peptide vaccines, and molecular targeting therapy. This review addresses recent advances in basic and clinical aspects of ENKTL-NT, especially its relation to EBV features.

Clinicopathological and prognostic study of primary cutaneous extranodal natural killer/T-cell lymphoma, nasal type: A systematic review

Comprehensive studies of primary cutaneous extranodal natural killer/T-cell lymphoma (PCENKTL) are scarce. The objectives of this study are to describe PCENKTL in terms of its clinical features, histopathology, immunophenotypes, and prognosis, and to analyze factors affecting patient survival outcomes. We searched four databases and include studies with extractable data. We also searched the Asan Medical Center database for cases of PCENKTL. We include a total of 289 patients. The mean age at diagnosis was 52.8 years and the female to male ratio was 1:1.2. The most common clinical morphology was a subcutaneous nodule, followed by ulceration. About half of the patients presented with disseminated skin lesions. The median overall survival was 12.0 months and the 5-year survival rate was 22.0%. There was no correlation between the clinical morphology or the histopathological features of the skin lesions with the patient outcomes. Advanced TNM stage, a disseminated skin lesion, tumor location on the leg or trunk, the presence of B symptoms, and a high International Prognostic Index score were associated with a worse prognosis, and chemoradiotherapy was associated with a better survival outcome as compared with chemotherapy alone in univariable analyses. In multivariable analyses, only advanced TNM stage and tumor location on the leg were associated with a worse prognosis. In conclusion, PCENKTL is an aggressive cutaneous lymphoma and its prognosis is associated with TNM stage and tumor location.

Clinical impact of lymphatic spread in patients with limited-stage upper aerodigestive tract NK/T cell lymphoma

Background

We investigated whether distance_max, that is, the degree of distance between the upper aerodigestive tract (UAT) mass and the farthest pathologic lymph node, was significantly associated with survival in patients with limited-stage UAT natural killer/T cell lymphoma (NKTCL).

Methods

A total of 157 patients who received chemotherapy (CTx) with/without radiotherapy (RTx) were enrolled.

Results

In the survival analysis, an elevated lactate dehydrogenase level [progression-free survival (PFS) hazard ratio (HR), 2.948; 95% confidence interval (CI), 1.606‒5.404; P<0.001; overall survival (OS) HR, 2.619; 95% CI, 1.594‒4.822; P=0.003], short distance_max (PFS HR, 0.170; 95% CI, 0.071‒0.410; P<0.001; OS HR, 0.142; 95% CI, 0.050‒0.402; P< 0.001), and CTx combined with RTx (HR, 0.168; 95%CI, 0.079‒0.380; P<0.001; OS HR, 0.193; 95% CI, 0.087‒0.429; P<0.001) had an independent predictive value for PFS and OS.

Conclusion

The evaluation of the degree of lymphatic spread and local control by CTx combined with RTx is essential in patients with limited-stage UAT NKTCL.

EGR1 as a potential marker of prognosis in extranodal NK/T-cell lymphoma

Extranodal natural killer T-cell lymphoma (ENKTL) is an aggressive malignancy with a dismal prognosis. In the present study, gene expression profiling was performed to provide more information on ENKTL molecular signature and offer a rationale for further investigation of prognostic markers in ENKTL. NanoString nCounter Analysis encompassing 133 target genes was used to compare gene expression levels of 43 ENKTL tumor samples. The majority of the patients were under 60 years of age (79.1%); 32 (74.4%) patients had nasal type ENKTL and 23 patients (53.5%) had intermediate/high risk ENKTL based on the prognostic index for natural killer cell lymphoma (PINK). The median follow-up was 15.9 months and the median overall survival (OS) was 16.1 months (95% CI 13.0-69.8). EGR1 upregulation was consistently identified in the localized stage with a low risk of prognostic index based on the PINK. Among the six significantly relevant genes for EGR1 expression, high expression levels of genes, including CD59, GAS1, CXCR7, and RAMP3, were associated with a good survival prognosis. The in vitro test showed EGR1 modulated the transcriptional activity of the target genes including CD59, GAS1, CXCR7, and RAMP3. Downregulation of EGR1 and its target genes significantly inhibited apoptosis and decreased chemosensitivity and attenuated radiation-induced apoptosis. The findings showed EGR1 may be a candidate for prognostic markers in ENKTL. Considerable additional characterization may be necessary to fully understand EGR1.

Case Report: Primary NK/T Cell Lymphoma Nasal Type of the Colon With Multiple Intestinal Perforations

Background: Extranodal NK/T cell lymphoma is a rare non-Hodgkin lymphoma mainly involving the upper aerodigestive tract, even rarer is primary extranasal disease involving the intestine. We present a case of primary intestinal NK/T cell lymphoma with diagnostic challenge, which eventually developed into multiple intestinal perforations.

Case Presentation: A 35-year-old man presented with diarrhea and recurrent fever. Abdominal CT revealed multi-segmental intestinal wall thickening. Colonoscopy showed multiple irregular ulcers in colon. During the hospitalization, the patient developed intestinal perforation and an emergency surgery was performed. The resected specimen showed multiple perforations of the colon. The surgical samples underwent pathological analysis, and a diagnosis of extranodal NK/T cell lymphoma nasal type was confirmed. After recovering from surgery, the patient started receiving chemotherapy and PD-1 monoclonal antibody. Fortunately, he was discharged after significant improvement in his general condition. Eleven months follow-up was uneventful.

Conclusion: Early diagnosis of primary intestinal NK/T cell lymphoma is frequently difficult. Most patients were definitely diagnosed only after surgical resection following complications, resulting in a poor prognosis. Therefore, doctors should maintain high suspicion of this malignancy for early diagnosis at an early stage clinically.

A composite single-nucleotide polymorphism prediction signature for extranodal natural killer/T-cell lymphoma

Current prognostic scoring systems based on clinicopathologic variables are inadequate in predicting the survival and treatment response of extranodal natural killer/T-cell lymphoma (ENKTL) patients undergoing non-anthracyline-based treatment. We aimed to construct a classifier based on single-nucleotide polymorphisms (SNPs) for improving predictive accuracy and guiding clinical decision-making. The data of 722 patients with ENKTL from international multicenters were analyzed. A 7-SNP-based classifier was constructed using LASSO Cox regression in the training cohort (n=336) and further validated in the internal testing (n=144) and two external validation cohorts (n=142; n=100). The 7-SNP-based classifier showed good prognostic predictive efficacy in the training cohort and the three validation cohorts. Patients with high and low risk scores calculated by the classifier exhibited significantly different progression-free survival (PFS) and overall survival (OS) (all p<0.001). The 7-SNP-based classifier was further proved to be an independent prognostic factor by multivariate analysis, and its predictive accuracy was significantly better than clinicopathological risk variables. The application of the 7-SNP-based classifier was not affected by sample types. Notably, chemotherapy combined with radiotherapy significnalty improved PFS and OS versus radiotherapy alone in high risk Ann Anbor stage I patients, while there was no statistical difference between the two therapeutic modalities among low risk patients. A nomogram was constructed comprised of the classifier and clinicopathological variables, and showed remarkably better predictive accuracy than that of each variable alone. The 7-SNP-based classifier is a complement to existing risk stratification systems in ENKTL, which could have significant implications for clinical decision-making for ENKTL patients.

The Clinical Features and Survival Outcome of 107 Newly Diagnosed Advanced Stage Extranodal NK/T-Cell Lymphoma Cases: A Triple-Center Study

Objective

Advanced stage extranodal natural killer/T-cell lymphoma (ENKTL) is a distinct type of non-Hodgkin lymphoma and the prognosis of ENKTL is poor with current treatment. This study aimed to investigate the clinical features, treatment strategy and survival outcome in patients with advanced stage ENKTL.

Patients and Methods

A total of 107 patients with newly diagnosed advanced stage ENKTL between January 2010 and December 2014 were reviewed from three cancer centers. Survival probability was calculated using Kaplan-Meier and the survival curves were compared by Log rank test. Cox regression analyses was performed to investigate the prognostic factors in ENKTL.

Results

The median patient age in our cohort was 42.0 years, with a male to female ratio of around 2.3:1. Over half of the patients had B symptoms (n = 61), high IPI scores (≥ 2, n = 60) and high Prognostic Index of Natural Killer Lymphoma (PINK) scores (≥ 3, n = 69). Elevated LDH level was present in around half of the patients (44/91). Most patients (n = 88) in our cohort originated in upper aerodigestive tract and the remaining 19 cases presented with non-upper aerodigestive tract involvement at first diagnosis. Chemotherapy regimens used in our study mainly include CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) (n = 26), L-asparaginase (L-asp) containing chemotherapy (GELOXD (gemcitabine, l-asparaginase, oxaliplatin and dexamethasone) and SMILE (L-asparaginase, methotrexate, ifosfamide, etoposide, and dexamethasone)) (n = 66). No significant difference between the baseline clinical characteristics was found between the L-asp and CHOP group. The CR rate after treatment was 39.3% (42/107) for the whole cohort. The 3-year progression-free survival (PFS) and 3-year overall survival (OS) rate was 41.0% and 41.5%, respectively. The 3-year PFS (49.2% vs 26.5%, P = 0.048) and 3-year OS (49.4% vs 26.0%, P = 0.030) was significantly higher in the L-asp group than the CHOP group. Patient CR status and PINK score were proved to be significant independent factors affecting OS and PFS by multivariate analysis. The grade 3/4 hematologic toxicity (P = 0.0003) and non-hematologic toxicity (P = 0.0002) occurred more frequently in the SMILE group than the GELOXD group.

Conclusion

Our results demonstrated that L-asp containing chemotherapy could provide favorable survival outcomes in patients with advanced stage ENKTL.

Allogeneic Hematopoietic Stem Cell Transplantation in Extranodal Natural Killer/T-cell Lymphoma

Objective

Extranodal NK/T-cell lymphoma (ENKL) is aggressive and resistant to chemotherapy and radiotherapy. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment for high-risk lymphomas owing to its associated graft-versus-lymphoma (GVL) effect. However, its application to ENKL is limited. We aim to summarize the characteristics of allo-HSCT for ENKL and, more importantly, evaluate whether allo-HSCT could offer any benefits for ENKL.

Materials and Methods

A systematic review and data analysis were performed to evaluate the performance of allo-HSCT in the treatment of ENKL using studies obtained from PubMed, Medline, and Embase from January 2000 to December 2019 in the English language.

Results

A total of 136 cases from 17 eligible publications were included in this study. It was found that after allo-HSCT, with an average follow-up time of 34 months (range: 1-121 months), 37.5% (52) of 136 patients had acute graft-versus-host disease (GVHD) and 31.6% (43) had chronic GVHD. Furthermore, 35.3% (48) of the patients were reported to have relapsed, but 2 of those relapsed only locally and achieved complete remission (CR) again with additional irradiation, chemotherapy, and donor lymphocyte infusions for one and rapid tapering and discontinuation of cyclosporine for the other, earning more than one year of extra survival. Finally, of the 136 patients, 51.5% (70) died because of primary disease progression (42.9%), infection (20.0%), GVHD (11.4%), organ failure (7.1%), hemorrhage (4.3%), and other causes (not specified/unknown) (14.3%).

Conclusion

Allo-HSCT may be a treatment option for advanced or relapsed/refractory ENKL, but its role still requires more rigorous future studies.

Nomograms based on SUVmax of 18F-FDG PET/CT and clinical parameters for predicting progression-free and overall survival in patients with newly diagnosed extranodal natural killer/T-cell lymphoma

BACKGROUND

The prognostic value of ¹⁸F-FDG PET/CT in extranodal natural killer/T-cell lymphoma (ENKTL) is not well established. We aimed to develop nomograms for individualized estimates of progression-free survival (PFS) and overall survival (OS) in patients with ENKTL using ¹⁸F-FDG PET/CT parameters and clinical parameters.

METHODS

A total of 171 patients with newly diagnosed ENKTL undergoing ¹⁸F-FDG PET/CT scanning were retrospectively analyzed. Nomograms were constructed according to multivariate Cox proportional hazards regression. The predictive and discriminatory capacities of the nomograms were then measured using the concordance index (C-index), calibration plots, and Kaplan-Meier curves. The C-index, the area under receiver operating characteristic (ROC) curve (AUC), and decision curve analysis (DCA) were used to contrast the predictive and discriminatory capacities of the nomograms against with the International Prognostic Index (IPI) and Korean Prognostic Index (KPI).

RESULTS

Multivariate analysis demonstrated that pretreatment SUVmax≥9.5, disease stage II and III-IV, elevated lactate dehydrogenase (LDH), and elevated β2-microglobulin (β2-MG) had the strongest association with unfavorable PFS and OS. In addition, hemoglobin (Hb) < 120 g/L had a tendency to be associated with PFS. Both nomogram models incorporated SUVmax, Ann Arbor stage, LDH, and β2-MG. The PFS nomogram also included Hb. The nomograms showed good prediction accuracies, with the C-indexes for PFS and OS were 0.729 and 0.736, respectively. The calibration plots for 3-year and 5-year PFS/OS reported good consistency between predicted and observed probabilities for survival time. The PFS and OS were significantly different according to tertiles of nomogram scores (p < 0.001). The C-index and AUCs of the nomograms were higher than that of IPI and KPI. Moreover, DCA showed that the predictive accuracy of the nomograms for PFS and OS were both higher than that of IPI and KPI.

CONCLUSIONS

This study established nomograms that incorporate pretreatment SUVmax and clinical parameters, which could be effective tools for individualized prognostication of both PFS and OS in patients with newly diagnosed ENKTL.

Durable Response to Sintilimab and Chidamide in a Patient With Pegaspargase- and Immunotherapy-Resistant NK/T-Cell Lymphoma: Case Report and Literature Review

The prognosis of patients with relapsed/refractory NK/T-cell lymphoma (NKTCL) is dismal. Immunotherapy has showed encouraging anti-tumor activity in patients with asparaginase-resistant NKTCL; however, only a portion of patients benefit and the median response duration is rather short. Treatment strategies have not been identified for immunotherapy-resistant NKTCL. We describe a patient with primary cutaneous NKTCL experienced disease progression after pegaspargase-based chemotherapy and PD-1 inhibitor (sintilimab)-based immunotherapy. Following a combined treatment of sintilimab and the HDAC inhibitor chidamide, the patient achieved a durable complete molecular response with mild toxicity. This case indicates that the combination of PD-1 inhibitor and HDAC inhibitor might be a treatment choice for immunotherapy-resistant NKTCL.

NK/T-cell non-Hodgkin lymphoma: Case report and review of the literature

Natural killer (NK)/T-cell lymphomas represent a rare type of lymphoid malignancy with mostly extranodal involvement, having NK cell or (rare) T cell lineage, classified by the World Health Organization into several subtypes which can involve the head and neck region, with the most frequent one being the nasal type. This article presents the case of a 31-year-old patient who presented at the Emergency Unit of Saint Andrew Emergency Clinical Hospital of Galati suffering from mycosis fungoides-like cutaneous lesions, associated with partial left eyelid ptosis of unknown etiology, as well as a poor health status with fever and respiratory failure. The final diagnosis was NK/T-cell non-Hodgkin lymphoma, possibly nasal type with medium sized T cells. The complexity of the rare diagnosis, associated with the unusual rapid patient evolution towards exitus 3 months after diagnosis, the intra-orbital metastatic involvement and the absence of a standardized treatment are case peculiarities, some of which are consistent with current literature data.

A proposal for a prognostic index for non-nasal type natural killer/T cell lymphoma after asparaginase-based treatment

In the era of asparaginase-based therapy for extranodal natural killer/T cell lymphoma (ENKTL), the clinical outcomes of ENKTL have notably improved. However, as a rare subtype of ENKTL, the therapeutic effect and prognostic factors of non-nasal type ENKTL remain unclear. Thus, we performed this study to analyze the clinical characteristics and to establish a prognostic model specifically for the non-nasal disease. We performed a retrospective study of consecutive patients newly diagnosed with non-nasal type ENKTL and mainly received asparaginase-based therapy at Sun Yat-sen University Cancer Center (SYSUCC) between January 2011 and December 2019, to analyze the prognostic factors and to propose a prognostic model. We validated the prognostic model in an independent cohort. In total, 98 non-nasal type ENKTL patients were included in the training cohort. Multivariate analyses showed that prognostic factors for OS were elevated LDH levels, involvement of bone marrow and serum total protein (TP) < 60 g/L. We developed a new prognostic model named the non-nasal type ENKTL prognostic index (NPI) by grouping the prognostic factors: group 1, no risk factors; group 2, one risk factor; and group 3, two or three risk factors, which were associated with 3-year OS rates of 84.1% (95% CI, 70.9-97.2), 46.8% (27.7-65.8), and 14.9% (0-32.9), respectively (P < 0.001). These results were validated and confirmed in an independent cohort. The new model is efficient in distinguishing non-nasal-type ENKTL patients with various outcomes in the contemporary era of asparaginase-based therapy.

Allogeneic stem cell transplantation for patients with aggressive NK-cell leukemia

Aggressive NK-cell leukemia (ANKL) has a fulminant clinical course with a poor prognosis. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is currently the only curative treatment. Using the Japanese transplant registry data, the outcomes of 59 ANKL patients who underwent first allo-HSCT were analyzed. Twenty-nine patients received stem cells from cord blood (CB), 18 from peripheral blood, and 12 from bone marrow. At the time of transplant 21 patients had complete response (CR), and 7 partial response (PR), but 31 without response. The 1-year and 5-year overall survival (OS) were 33.9% and 27.3%, respectively. The 1-year cumulative incidences of relapse or progression was 55.5%, and that of non-relapse mortality was 12.1%. The OS was significantly better for patients with CR or PR at the time of allo-HSCT (P = 0.046), which was equivalent to that for patients who experienced primary induction failure at the time of allo-HSCT but achieved CR afterwards (40.6% versus 32.0% at 5 years; P = 0.95). Patients receiving CB had a significantly better OS than those receiving stem cells from others (37.3% versus 16.2% at 5 years; P = 0.04). Patients achieving event-free survival at 12 months after allo-HSCT had good outcomes with 5-year OS of 85.2%.

Prognostic Nutritional Index, Another Prognostic Factor for Extranodal Natural Killer/T Cell Lymphoma, Nasal Type

Objective: The prognostic nutritional index (PNI) is a significant prognostic factor in diffuse large B cell lymphoma, follicular lymphoma, and other malignancies. The current study aimed to explore its prognostic role in extranodal natural killer/T cell lymphoma (ENKTL).

Methods: Patients diagnosed with ENKTL and treated during 2002 and 2018 (n = 184) were retrospectively recruited. PNI was calculated from albumin concentration (g/L) and total lymphocyte count (^*10⁹/L). The association of PNI and overall survival (OS) or progression-free survival (PFS) was assessed in univariate analysis and multivariate Cox regression validated by the 10-fold cross-validation method.

Results: Survival analyses showed that both OS and PFS differed significantly between PNI groups stratified by a cutoff value of 49.0. The 3- and 5-year OS were 42.5 and 36.3% in the low-PNI (PNI < 49) subgroup and 70.6% and 63.9% (P < 0.001) in the high-PNI (PNI ≥ 49) subgroup, respectively. The corresponding PFS showed a similar pattern (38.4, 32.4 vs. 64.8, 54.0%, P < 0.001). Multivariate analysis indicated that PNI was significantly independent for both OS (HR = 0.517, 95% CI = 0.322–0.831, P = 0.006) and PFS (HR = 0.579, 95% CI = 0.373–0.899, P = 0.015). Furthermore, integrating PNI into the models of IPI (International Prognostic Index), KPI (Korean Prognostic Index), and PINK (prognostic index of natural killer lymphoma) could improve the area under the curve (AUC) and reduce the integrated Brier score (IBS) and Akaike Information Criterion (AIC) value of each model.

Conclusion: PNI was a significant prognostic indicator for ENKTL.

Combined gemcitabine, cisplatin, dexamethasone, methotrexate, and pegaspargase (GDP-ML) for patients with newly diagnosed extranodal natural killer/T cell lymphoma, nasal type: a single arm, single center, prospective phase 2 study

Extranodal natural killer/T cell lymphoma, nasal type (ENKL) is a highly aggressive tumor with relatively poor prognosis. In this prospective study, we investigated the efficacy and toxicity of a novel GDP-ML regimen (combined gemcitabine, cisplatin, dexamethasone, methotrexate, and pegaspargase) as front-line treatment in newly diagnosed ENKL. Eligible newly diagnosed stage I/II ENKL patients received sandwich chemoradiation therapy. Patients with stage III/IV disease received an initial 4 cycles of GDP-ML regimen. After 4 cycles, responding patients continued to receive either autologous transplantation or additional two courses of GDP-ML. A total of 44 patients were enrolled with a median follow-up of 26 months. The overall response rate (ORR) were 78.6% for the whole cohort, 84.6% for stage I/II, and 66.7% for stage III/IV, and corresponding complete remission (CR) rates were 61.9%, 76.9%, and 33.3%. The 1- year and 2- year progression-free survival (PFS) rates were 69.3% and 62.9%, and 1- year and 2-year overall survival (OS) rates were 76.5% and 67.4%, respectively. Patients with stage I/II disease showed better 2-year OS rate compared with stage III/IV patients (88.1% vs. 33.2%, p < 0.001). Patients who achieved CR had significantly better 2-year OS rate compared with non-CR patients (90.8% vs. 24.5%, p < 0.001). The main adverse event was hematologic toxicity. Grade 3/4 neutropenia occurred in 59.1% of patients. These results indicate that GDP-ML is an effective and well-tolerated induction regimen with newly diagnosed ENKL patients. This clinical trial was registered on www.chictr.org.cn (ChiCTR-ONC-12002055).

Epstein - Barr virus positive T and NK-cell lymphoproliferations: Morphological features and differential diagnosis

The spectrum of Epstein-Barr virus (EBV)-positive T and NK-cell lymphoproliferations is broad and ranges from reactive self-limited disorders to neoplastic processes with a fulminant clinical course. EBV plays an important role promoting lymphomagenesis, although the precise mechanisms remain elusive. EBV-positive lymphoproliferative disorders (LPD) are more common in East Asia (China, Japan, Korea and Taiwan), and Latin America suggesting a strong genetic predisposition. The revised 2016 World Health Organization (WHO) lymphoma classification recognizes the following malignant NK- and T-cell lymphomas; extranodal NK/T-cell lymphoma, nasal type (ENKTCL), aggressive NK-cell leukemia (ANKL), and the provisional entity within the group of peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) "primary EBV-positive nodal T or NK cell lymphoma". Disorders presenting mainly in children and young adults include chronic active EBV infection (CAEBV) - systemic and cutaneous forms - which are not considered malignant disorders but were included in the WHO classification for the first time because of the differential diagnosis with other T- or NK-cell lymphomas. CAEBV, cutaneous form, includes hydroa vacciniforme-like LPD (HV-LPD) and severe mosquito bite allergy (SMBA). Finally, systemic EBV-positive T-cell lymphoma of childhood was recognized as lymphoma because of its fulminant clinical course. Given the shared pathogenesis of these disorders, overlapping features are common demanding a close clinical, morphological and molecular correlation for an accurate diagnosis. This review summarizes the clinical, histopathological and molecular features of EBV-associated T and NK-cell LPD, highlighting the main features that might aid in the differential diagnosis.

Prognostic nomogram for overall survival in upper aerodigestive tract extranodal natural killer/T-cell lymphoma, nasal type, stages IE and IIE: A SEER-based study

The present study aimed to develop a widely accepted prognostic nomogram for stage IE and IIE extranodal natural killer/T-cell lymphoma (ENKTCL) of the upper aerodigestive tract by using the Surveillance, Epidemiology, and End Results program database. A total of 396 patients with ENKTCL were included in the present study and were divided into training (n=280) and validation (n=116) cohorts. The Kaplan-Meier method and Cox regression model were used to evaluate the prognostic value of multiple clinical parameters on overall survival. The C-index and calibration curves were both used to determine the predictive and discriminatory capacities of the nomogram. In the training cohort, multivariate analysis demonstrated that age, primary site, radiation therapy and stage were independent prognostic factors. Nomograms with a C-index of 0.717 in the training cohort and a C-index of 0.737 in the validation cohort were developed. The calibration curves reported excellent consistency between predicted and real survival in patients with ENKTCL. In addition, a subgroup analysis of 264 patients who were receiving chemotherapy revealed that based on chemotherapy, supplementation with radiation therapy was significantly beneficial to patients survival. In conclusion, the present study demonstrated that this prognostic model may serve as a novel tool for improving prediction of survival outcomes and may therefore be used in clinical applications.

[Extra-nodal NK/T-cell lymphoma, nasal-type, revealed by cutaneous and ocular involvement]

BACKGROUND

Extra-nodal NK/T-cell lymphoma (ENKTL) is a form of highly malignant non-Hodgkin's lymphoma. There are two types: nasal forms primarily affecting the oropharyngeal sphere and so-called nasal-type extra-nasal forms in which primary skin involvement is the most common feature enabling diagnosis. Herein, we report a case of systemic nasal-type ENKTL (ENKTL-NT) that was diagnosed based on skin involvement associated with ocular involvement.

PATIENTS AND METHODS

A 67-year-old female patient, without immunodepression, was admitted to the dermatology department for a worsening inflammatory scaly patch of skin on her right calf. Secondarily, further lesions appeared on her body as well as a generalized macropapular rash and sores. These were associated with fever spikes, as well as ophthalmoplegia and edema, preventing her from opening her right eyelid. Tests for infectious, autoimmune and inflammatory disorders were negative. A cerebro-orbital scan revealed infiltration and contrast enhancement of the right periocular fat without any mass effect or cerebral extension. A positron emission tomography (PET) scan revealed multiple hypermetabolic skin lesions. Histological analyses indicated dermal-hypodermal lymphomatous tumor proliferation, and immunohistochemical analyses revealed lymphocytes expressing NK-cell markers (strong CD56+ expression), cytotoxic markers (granzyme B and TIA-1), and the presence of Epstein Barr virus (EBV) in the tumor cells. The patient was diagnosed with systemic ENKTL-NT. Her condition deteriorated rapidly, with the onset of refractory macrophage activation syndrome leading to death due to multiple organ failure.

DISCUSSION

Skin involvement in ENKTL is non-specific and uncommon, which can delay diagnosis. Treatment is based on polychemotherapy comprising L-asparaginase and possibly consolidation therapy with autologous or allogeneic hematopoietic stem cell transplantation. The prognosis of ENKTL-NT is poor due the more aggressive nature of the disease compared with the nasal forms, with frequent visceral involvement and macrophage activation syndrome. Skin involvement seems to be a poor prognostic factor. Although ocular involvement is documented, its association with skin involvement is rare and mainly secondary to nasal forms of ENKTL. This case of an extra-nasal form of ENKTL-NT with systemic involvement illustrates the difficulty of diagnosis and the poor prognosis of this type of lymphoma.