The diagnosis and management of NK/T-cell lymphomas

Case report: a critically ill patient with aggressive NK-cell leukemia receiving emergency chemotherapy in the ICU

Aggressive NK-cell leukemia (ANKL) is a scarce mature NK-cell neoplasm frequently associated with Epstein-Barr virus (EBV) infection. We report the case of a 47-year-old male patient who was admitted to the hospital due to recurrent fever, jaundice, and dyspnea, and was diagnosed with ANKL accompanied by multi-organ failure. Upon transfer to the intensive care unit (ICU), he received emergency chemotherapy consisting of etoposide, pegaspargase, and gemcitabine, in conjunction with organ support therapies including DPMAS, LPE, and CVVHD. Subsequently, the patient’s condition stabilized, and he was discharged. However, following the second cycle of chemotherapy, he was readmitted due to altered mental status. Due to financial constraints, the family decided not to pursue further treatment, leading to the patient’s eventual demise. Overall, this case highlights the critical importance of multidisciplinary collaboration for managing critically ill ANKL patients. Careful evaluation of the risks associated with chemotherapy, combined with timely administration of emergency chemotherapy in the ICU and comprehensive multi-organ support, can potentially offer a survival opportunity.

Interleukin-2-inducible T-cell kinase inhibition to block NF-κB signaling exerts anti-tumor effects and enhances chemotherapy in NK/T-cell lymphoma

Natural killer/T-cell lymphoma (NKTCL) is a highly aggressive non-Hodgkin lymphoma. Relapsed/refractory (R/R) NKTCL patients have dismal prognosis and lack effective treatments, novel therapeutics are urgently needed. Here we found interleukin-2-inducible T-cell kinase (ITK) expression was elevated in NKTCL cells and patient tumors. And higher ITK expression was associated with worse clinical outcomes. In vitro ITK knockdown inhibited NKTCL cell growth, induced apoptosis, cell cycle arrest and impaired its colony-forming ability while ITK overexpression accelerated cell proliferation. In vivo ITK knockdown greatly impeded lymphoma growth in mouse model, indicating it as a potential therapeutic target. Mechanistically, ITK knockdown inhibited NKTCL cell growth by attenuating oncogenic NF-κB signaling, which is revealed by transcriptomic profiling and further validated by in vitro assays and in vivo NKTCL models. Additionally, we showed that ITK inhibitors could inhibit NKTCL cell proliferation, promote apoptosis and suppressed tumor progression in NKTCL cell line-derived xenograft (CDX) model. Furthermore, we established a patient-derived xenograft (PDX) model from a NKTCL patient refractory to prior anti-PD-1 and asparaginase containing therapy. The primary cells from this patient highly expressed ITK and were responsive to ITK inhibitor. And ITK inhibitor effectively repressed tumor progression in PDX model. Finally, we found ITK inhibition improved the response of NKTCL cell lines to chemotherapy and overcome chemotherapy resistance in primary cells. Collectively, our results demonstrated that ITK served as an oncogene in NKTCL and represented a novel therapeutic vulnerability to be targeted or in combination with chemotherapy drugs for this disease.

Extranodal NK/T-cell lymphoma, nasal type-a case report and a review of the literature

Nasal-type extranodal NK/T-cell lymphoma (ENKTCL) is a unique type of mature NK/T-cell lymphoma that is closely related to the EBV virus (EBV). In most cases, ENKTCL occurs in the nasal cavity and other parts of the upper respiratory and digestive tract, and its clinical presentation is usually unremarkable, making it difficult to early diagnosis. We report a case of NK/T-cell lymphoma and its main clinical features and cytopathological characteristics.

Functional screening of somatic mutant events in extranodal natural killer/T-cell lymphoma with adrenal involvement

Background

Extranodal natural killer/T-cell lymphoma (ENKTL) involving the adrenal glands is extremely rare, and only a few cases have been reported. However, the genetic alterations, clinicopathological features and prognosis of these patients have not yet been fully elucidated.

Methods

Profiling of tumor mutations in ENKTL patients with adrenal involvement was conducted by whole-genome sequencing, and the predisposing genes and driver mutation gene variants were verified through Sanger sequencing. Immunohistochemical analysis of markers for the diagnosis and tumor microenvironment competent were performed to identify histopathological features. In addition, we searched the Surveillance, Epidemiology, and End Results (SEER), PubMed, Embase, and Scopus databases to perform a population-based study to compare the prognosis between adrenocortical carcinoma (ACC) patients and adrenal ENKTL patients using Kaplan-Meier survival curves and log-rank tests and analyzed the prognostic factors affecting the overall survival (OS) of adrenal ENKTL patients via univariate and multivariate Cox regression analyses.

Results

We screened 15892 somatic single-nucleotide variants (SNVs), 364 somatic insertions and deletions (INDELs), and four driver mutation genes, namely, TET2, STAT3, FAS, and TP53. In addition, immunohistochemical analysis revealed that tumor cells were positive for CD3, CD43, CD56, TIA1, granzyme B, CD2, CD4, and CD7. The immunohistochemistry for detecting components of the tumor microenvironment reveled the infiltration of tumor-associated macrophages (CD68, CD163) and tumor-associated fibroblasts (vimentin, SMA) in the tumor sample. According to our population-based analysis, Kaplan-Meier survival curves revealed that ENKTL patients with adrenal involvement had a significantly poorer prognosis than did patients with ACC (p<0.001), and chemotherapy was a significant prognostic factor for OS in ENKTL patients with adrenal involvement according to Cox multivariate analysis (hazard ratio = 0.318; p=0.027).

Conclusions

The metastasis of ENKTL to the adrenal gland may be due to gene mutations caused by genetic variations, which may provide new therapeutic targets for this disease. The prognosis of adrenal ENKTL patients is markedly worse than that of ACC patients, and chemotherapy may serve as an independent factor of OS in adrenal ENKTL patients. However, our findings still need to be validated in additional studies.

Presentation of extranodal NK/T-cell lymphoma as a pituitary mass: A case report and review of the literature

Background

Primary pituitary lymphomas are uncommon neoplasms that are typically derived from a B-cell lineage. Extranodal natural killer (NK)/T-cell lymphoma is distinct from B- and T-cell lymphomas and is associated with Epstein-Barr virus infection. Primary central nervous system (CNS) presentations of this neoplasm are exceptionally rare. Here, we report the case of extranodal NK/T-cell lymphoma presenting as a pituitary mass and review the literature related to this rare clinical entity.

Case Description

A 31-year-old previously healthy male presented with 2 weeks of progressive headaches and ophthalmoplegia. Imaging revealed a large intrasellar mass with retroclival extension and involvement of the sphenoid and cavernous sinuses. An endoscopic biopsy of the sphenoidal mucosa was performed, and pathological examination was consistent with extranodal NK/T-cell lymphoma. Despite treatment with chemo- and radiotherapy, the patient died approximately 8 months after initial presentation due to systemic disease progression with multiorgan failure.

Conclusion

The presentation of extranodal NK/T-cell lymphoma as a pituitary lesion is very rare, having been reported only twice in the previous literature. Patients with primary CNS extranodal NK/T-cell lymphoma typically experience an aggressive clinical course with a poor prognosis, as in our case.

Comparison of pegaspargase with concurrent radiation vs. P-GEMOX with sequential radiation in early-stage NK/T-cell lymphoma

Objectives

The optimal treatment strategy for early-stage natural killer/T-cell lymphoma (NKTCL) remains unclear. This study aimed to evaluate and compare the clinical outcomes and adverse events (AEs) associated with two treatment regimens for early-stage NKTCL: pegaspargase with concurrent radiation therapy (P+CCRT) and pegaspargase, gemcitabine, and oxaliplatin (P-GEMOX) with sequential radiation therapy (SERT). Propensity score matching (PSM) was employed to ensure balanced comparison between these regimens.

Methods

We assessed the efficacy of P+CCRT from a phase II trial and P-GEMOX combined with SERT using real-world data. PSM was conducted at a 1:1 ratio with a caliper of 0.18 to align baseline characteristics between the treatment groups. Key outcomes analyzed included overall response rate (ORR), complete response rate (CR), progression-free survival (PFS), overall survival (OS), and AEs.

Results

Following PSM, the study included 52 patients, with 26 in each treatment group. Baseline characteristics were balanced between the cohorts. The ORR for P+CCRT group was 100.0% compared to 88.5% for P-GEMOX+ SERT group, and the CR rates was 100.0% vs. 76.9%, respectively. The 3-year OS and PFS rates were both 92.3% for P+CCRT, while P-GEMOX showed 92.3% OS and 80.8% PFS. Adverse events, including hematological toxicity, hepatotoxicity, and coagulation dysfunction, were comparable between the two regimens.

Conclusion

P+CCRT is associated with comparable clinical outcomes compared to P-GEMOX + SERT in early-stage NKTCL, with comparable adverse events. Additionally, P+CCRT offers the benefit of a more streamlined treatment regimen with a shorter cycle. Given these encouraging results, further cohort studies are needed to validate these results.

Diagnostic challenge presented by extranodal NK/T cell lymphoma expressing CD20, CD30 and CD15: A case report

The atypical expression of immune phenotypes in lymphoma is often associated with a poor prognosis and presents diagnostic challenges. The present study reports on a rare extranodal NK/T cell lymphoma. In addition to typical morphology and immunohistochemical characteristics, these tumors strongly express CD20 and CD30 and partially express CD15, which is associated with aggressive clinical behavior. Differential diagnosis should be cautiously approached in extranodal NK/T cell lymphoma because the abovementioned markers are typically expressed in B cell lymphoma or Hodgkin's lymphoma. In addition to rigorous histological and comprehensive immunohistochemical staining, whole-body imaging and molecular testing can assist with diagnosis. In the present case, the patient died of multiple organ failure shortly after diagnosis. Lymphoma exhibits an atypical immunophenotype, thus emphasizing the importance of a thorough analysis of the interrelations among clinical, imaging and pathological features.

MiR-340-5p regulates PD-L1 and predicts pembrolizumab response in extranodal NK/T-cell lymphoma

Extranodal NK/T-cell lymphoma (ENKTL) is an aggressive, chemoresistant non-Hodgkin lymphoma subtype with poor patient outcomes linked to elevated PD-L1 expression. This study investigates miRNA-mediated regulation of PD-L1, focusing on miR-340-5p and miR-424-5p as novel therapeutic targets and predictive biomarkers for pembrolizumab response. Through miRNA sequencing and functional assays, miR-340-5p and miR-424-5p were identified as key modulators of PD-L1 in drug-resistant ENKTL cells, with their roles validated via ribonucleoprotein immunoprecipitation and luciferase reporter assays. Notably, elevated miR-340-5p levels in PD-L1-negative ENKTL tissues were inversely correlated with soluble PD-L1, implicating miR-340-5p in immune evasion mechanisms. Additionally, low serum levels of miR-340-5p were associated with reduced pembrolizumab efficacy, positioning miR-340-5p as a promising predictive biomarker for immune checkpoint blockade. These findings suggest that pre-treatment assessment of serum miR-340-5p could guide pembrolizumab therapy in ENKTL, optimizing treatment outcomes. Validation in larger cohorts is necessary to confirm the utility of miR-340-5p as a predictive biomarker for ENKTL immunotherapy.

Haematogenous seeding in mycosis fungoides and Sézary syndrome: current evidence and clinical implications

Cutaneous T-cell lymphomas (CTCLs) are a heterogeneous group of diseases characterized by abnormal neoplastic T-cell growth in the skin. Mycosis fungoides (MF), the most common CTCL, manifests as erythematous skin patches and/or plaques, tumours or erythroderma. The disease may involve blood, lymph nodes and rarely viscera. Sézary syndrome (SS) is a unique leukaemia/lymphoma syndrome related to MF, which presents with blood and skin involvement at diagnosis. The pathogenesis of MF/SS is not fully elucidated. The presence of skin lesions at distant sites underpins a hypothesis that MF/SS lesions may develop through haematogenous seeding. Phenotypic similarities between malignant and normal T cells led to the notion that disease-initiating mutations occur in specific subtypes of mature T cells, which are responsible for most CTCLs. However, this mature T-cell precursor model is not always consistent with clinical observations and research on MF/SS pathogenesis. Here, we review evidence supporting an alternative model of pathogenesis for MF/SS involving haematogenous seeding as a key process responsible for the initiation and progression of the disease. According to this hypothesis, malignant transformation occurs at an early stage of T-cell development (probably in bone marrow or thymus), yielding circulating neoplastic T cells which colonize the skin where the microenvironment is most permissive for proliferation and evolution. These mutated precursor cells seed the skin where they find a suitable niche to develop into clinically perceptible disease. Subsequently, malignant T cells can re-enter the bloodstream, re-seed pre-existing lesions and seed new areas of the skin, causing synchronous and convergent changes in the transcriptomic profile of lesions and tumours, and clinical disease progression - 'consecutive haematogenous seeding' captures this temporal phenomenon. This model radically changes the current understanding of CTCL pathogenesis, transforming it from a primarily cutaneous disease with secondary involvement of blood, to a systemic disease, where the spread of malignant cells through the blood to the skin is not a phenomenon of advanced disease but is an essential component of pathogenesis. This understanding of MF/SS could have several clinical implications, including standardizing our approach to assessing blood tumour burden, potential advances in prognosis and monitoring, and investigating combination treatments to improve patient outcomes.

A Multidisciplinary Approach to Diagnosing Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN): Practical Recommendations and Insights from Countries of the Gulf Cooperation Council

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an aggressive orphan hematopoietic malignancy characterized by cutaneous and systemic hematologic involvement. BPDCN is frequently misidentified, but early, accurate diagnosis is critical to extending patient survival using tagraxofusp, a first-in-class CD123-targeted therapy, and increasing their chances of receiving a potentially curative stem cell transplantation. Cases of BPDCN in countries of the Gulf Cooperation Council are lower than the extrapolated incidence from other geographic locations due to lack of awareness of key diagnostic features, lack of consensus on the minimal phenotype for diagnosis, and lack of local immunohistochemistry testing facilities, contributing to underdiagnosis in this region. Practical recommendations, a streamlined diagnostic panel, and suggested multidisciplinary approaches based on expert experience regarding diagnostic and clinical challenges specific to this region, and a review of the literature are presented here to facilitate diagnosis of BPDCN in this region by primary care physicians, dermatologists, and hematologists.

A prognostic index for advanced-stage extranodal natural killer/T-cell lymphoma: A multicenter study

Advanced-stage extranodal natural killer/T-cell lymphoma (ENKTL) is a highly heterogeneous disease with very poor prognosis. All commonly utilized prognostic models incorporated both early-stage and advanced-stage patients in the modeling process. This study aim to design a prognostic model specifically for advanced-stage ENKTL, providing risk stratification in affected patients. We analyzed 291 patients with stage III/IV ENKTL receiving asparaginase-based chemotherapy from 8 institutions to develop a new prognostic model and validate it in an independent cohort consisted of 221 patients from 4 additional hospitals. The prognostic model included three independent variables based on a multivariate analysis for overall survival (OS): age, bone marrow invasiveness and visceral organ involvement. We identified three different risk groups: group 1, no adverse factors; group 2, one factor; and group 3, two or three factors, which were associated with 5-year OS rates of 66.0%, 32.3%, and 20.0%, respectively (P < 0.001). The prognostic index of natural killer lymphoma (PINK) and nomogram-revised risk index (NRI) were unsatisfactory for stratifying these patients. These results were validated and confirmed in an independent cohort. This newly proposed model can be used to guide risk-adapted treatment for advanced stage ENKTL.

APOC1 inhibit NKTCL doxorubicin sensitivity by promoting mitophagy

NKTCL is a highly aggressive malignant tumor, especially prevalent in the southern regions of China. Although chemotherapy regimens based on ADM have achieved certain therapeutic effects in early treatment, the issue of ADM resistance severely limits the therapeutic efficacy and makes it difficult to improve patient survival rates. Our research results indicate that the expression level of APOC1 is closely related to the sensitivity of NKTCL cells to ADM. The upregulation of APOC1 may promote mitophagy, clear damaged mitochondria, stabilize the intracellular environment, and enhance the tolerance of tumor cells to ADM. Furthermore, APOC1 may further affect the formation of mitophagy and drug resistance by activating specific signaling pathways, such as the STAT3 signaling pathway. Animal experiments further confirm the conclusions of in vitro experiments, showing that APOC1 regulates mitophagy through p-STAT3Tyr705, thereby promoting the drug resistance of NKTCL. These findings provide a new perspective for the development of novel therapeutic strategies targeting APOC1 and its associated signaling pathways, which may help overcome the issue of ADM resistance in NKTCL.

A differential diagnosis method for systemic CAEBV and the prospect of EBV-related immune cell markers via flow cytometry

Chronic active Epstein-Barr virus (CAEBV) infection of the T-cell or Natural killer (NK)-cell type, systemic form (systemic CAEBV or sCAEBV) was defined by the WHO in 2017 as an EBV-related lymphoproliferative disorder and is listed as an EBV-positive T-cell and NK-cell proliferation. The clinical manifestations and prognoses are heterogeneous. This makes systemic CAEBV indistinguishable from other EBV-positive T-cell and NK-cell proliferations. Early diagnosis of systemic CAEBV and early hematopoietic stem cell transplantation can improve patient prognosis. At present, the diagnosis of systemic CAEBV relies mainly on age, clinical manifestations, and cell lineage, incurring missed diagnosis, misdiagnosis, long diagnosis time, and inability to identify high-risk systemic CAEBV early. The diagnostic methods for systemic CAEBV are complicated and lack systematic description. The recent development of diagnostic procedures, including molecular biological and immunological techniques such as flow cytometry, has provided us with the ability to better understand the proliferation of other EBV-positive T cells and NK cells, but there is no definitive review of their value in diagnosing systemic CAEBV. This article summarizes the recent progress in systemic CAEBV differential diagnosis and the prospects of flow cytometry.

Expression of senescence-related CD161 promotes extranodal NK/T cell lymphoma by affecting T cell phenotype and cell cycle

PURPOSE

The intention of this work is to probe the role of senescence-related gene CD161 in extranodal NK/T cell lymphoma (ENKTL).

METHODS

This study used H2O2 to establish three distinct in vitro oxidative stress aging models (NKL, SNT-8, and YT). Western blotting was employed to assess the levels of two iconic aging proteins, MMP1 and P53, and flow cytometry was utilized to investigate cell cycle and the expressions of CD4, CD8, and CD161. Cell viability was evaluated via the CCK-8 assay. The transcriptome analysis assessed the differential gene expression between the control and aging group of NKL. In vivo, we established a BALB/c mice aging tumor model. After 15 days, the mice were euthanized to harvest tumors. ELISA was employed to measure aging indicators in the mouse tissues. Flow cytometry was utilized to assess the levels of CD4, CD8, and CD161 in tumor samples. Hematoxylin-eosin (HE) staining was performed to evaluate the structure and cellular morphology of the tumor tissue.

RESULTS

In the NKL, SNT-8 and YT aging models, the levels of MMP1 and P53 proteins were significantly increased. Flow cytometry results indicated that all three cell types exhibited marked arrest in the G1 phase. Compared with the control group, the expressions of CD4 and CD161 in the aging group were significantly increased, while the expression of CD8 was decreased. Transcriptome analysis revealed 2,843 differentially expressed genes (DEGs) between the control and aging groups, with 2,060 up-regulated and 783 down-regulated genes identified. Following CD161 knockdown, cell viability of three cell types in the aging group was significantly reduced compared to the control group. The G1 phase of the cells was significantly interrupted. The expressions of CD4 and CD161 were significantly increased, and the expression of CD8 was decreased. However, in the aging + si-CD161 group, a partial alleviation of oxidative stress was observed with a reduction in CD161 expression levels. Animal experiments demonstrated that knockout of CD161 can inhibit tumor progression and partially mitigate oxidative stress.

CONCLUSIONS

CD161 may inhibit ENKTL tumor development by regulating cell cycle and T-cell phenotype.

Rare Head and Neck Cancers and Pathological Diagnosis Challenges: A Comprehensive Literature Review

Head and neck cancers (HNCs) arise from anatomically adjacent sites and subsites, with varying etiological factors, diagnostic strategies, prognoses, and treatment approaches. While conventional squamous cell carcinoma (SCC) is the most common histology in the head and neck district, HNCs encompass a variety of rare histopathological entities, categorized into epithelial tumors such as salivary gland cancers, sinonasal tumors, neuroendocrine tumors, malignant odontogenic tumors, and SCC variants versus non-epithelial tumors including soft tissue sarcomas, mucosal melanomas, and hematological malignancies. Rare HNCs (R-HNCs) represent a diagnostic and clinical challenge, requiring histopathological expertise, the availability of peculiar molecular analysis, and the personalization of local and systemic treatments, all guided by a multidisciplinary tumor board. Here, we provide a comprehensive literature review on R-HNCs, emphasizing key histopathological and molecular characteristics that are crucial for guiding treatment decisions. An insight about the latest developments in systemic treatments is also reported.

The role of auto-HSCT in extranodal natural killer/T cell lymphoma

Objectives

Autologous hematopoietic stem cell transplantation (auto-HSCT) is considered optional consolidation therapy especially for relapsed/refractory extranodal NK/T-cell lymphoma (ENKL), but its applications to newly diagnosed advanced-stage ENKL is currently limited.

Methods

We collected 51 cases of newly diagnosed advanced-stage ENKL patients, including 26 with auto-HSCT and 25 with chemotherapy rather than HSCT, from our hospital between 2014/01 and 2023/12. We summarized the patients' characteristics, conducted survival analysis of the 51 cases, and analyzed the potential benefits of auto-HSCT to ENKL patients.

Results

It shows that after a median follow-up time of 39 months, the estimated 5-year overall survival (OS) of the 51 newly diagnosed advanced-stage ENKL patients is 73.4%, and their estimated 5-year progression-free survival (PFS) is 73.4%. For patients receiving auto-HSCT, the 5-year OS (91.7%) and PFS (91.0%) are significantly different from those of patients receiving chemotherapy without HSCT (OS 53.3%, PFS 54.5%) (p < 0.05). Univariate and multivariate analysis results suggest that only the l-asparaginase usage in chemotherapy showed significant impact on the OS, and none of concerned factors showed significant impact on the PFS.

Conclusions

Auto-HSCT is indeed an option to newly diagnosed advanced-stage ENKL, but further studies are still required for more strict disease management.

From the midfacial destructive drama to the unfolding EBV story: a short history of EBV-positive NK-cell and T-cell lymphoproliferative diseases

Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that has been related to oncogenesis of lymphoid and epithelial malignancies. Although the mechanism of EBV infection of NK and T cells remains enigmatic, it plays a pathogenic role in various EBV+ NK-cell and T-cell lymphoproliferative diseases (LPDs), through promotion of cell activation pathways, inhibition of cell apoptotic pathways, behaving as oncogenes, interacting with host oncogenes or acting epigenetically. The study of NK-cell LPDs, previously hampered by the lack of immunophenotypical and genotypical criteria of NK cells, has become feasible with the recently accepted criteria. EBV+ NK- and T-cell LPDs are mostly of poor prognosis. This review delivers a short history from primeval to recent EBV+ NK- and T-cell LPDs in non-immunocompromised subjects, coupled with increasing interest, and work on the biological and oncogenic roles of EBV.

Optimization of immune checkpoint inhibitor treatment planning for relapsed or refractory extranodal NK/T cell lymphoma

Pembrolizumab (anti-programmed cell death-ligand 1 inhibitor) is a promising salvage therapeutic option for relapsed/refractory extranodal NK/T-cell lymphoma (R/R ENKTL). However, the appropriate duration of pembrolizumab use in R/R ENKTL patients and the optimal timing for administering pembrolizumab remain undetermined. We collected and analyzed clinical information on R/R ENKTL 58 patients who received pembrolizumab to evaluate the optimal treatment durations and clinical information for considering treatment interruption. Treatment outcomes were assessed by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and Epstein Barr virus DNA (EBV DNA) every 3 months. Nineteen (32.8%) patients had been treated with more than three chemotherapies before pembrolizumab administration. The best response rate towards the first try of pembrolizumab was 38.9% (31.5% complete response rate (CR), 7.4% partial response (PR)). During the 41.8-month median follow-up duration, the median progression-free survival (PFS) was 3.1 months, and the median overall survival (OS) was 7.1 months. The failure group, which was characterized by Deaville score (DS) 3-4 and circulating EBV detection, or DS 5 with/without EBV detection, had the worst PFS (p < 0.001) and OS (p < 0.001), followed by the high (DS 1-2 and EBV detection, or DS 3-4 and EBV not detected) and low-risk groups (DS 1-2 and EBV not detected). Among the 21 patients who achieved the best response at the first pembolizumab try, the patients who received planned 24 cycles presented better PFS than those who received incomplete cycles (57.6 months vs 20.9 months, P-value = 0.012). Among 13 patients who received avelumab or pembrolizumab in advance, a few who responded to the second trial of pembrolizumab administration had over one year of chemotherapy vacation. Determining the discontinuation or continuation of pembrolizumab would be considered in selected cases assessed by PET-CT and EBV monitoring. Disruption of pembrolizumab treatment may be advisable for the low-risk group(DS 1-2 and EBV not detected), whereas continuation could be warranted for the high-risk group (DS 1-2 and EBV detection, or DS 3-4 and EBV not detected). Moreover, it might be critical to maintain over 24 cycles to improve the survival outcome of R/R ENKTL.

Blastic plasmacytoid dendritic cell neoplasm of skin, a rare dermatohematologic malignancy-A case report

Key Clinical Message

Blastic plasmacytoid dendritic cell neoplasm is a rare hematologic malignancy and appropriate diagnosis encounters difficulties in both clinical and pathologic aspects. This case report aims to present a clinical case to help familiar clinicians and pathologists with this rare entity.

Abstract

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an uncommon hematologic malignancy. Because of the rarity of the disease and aggressive behavior, we present this case. A 71-year-old man presented with a forehead ulcerated skin lesion. On histopathologic examination, pan-dermal atypical mononuclear infiltrate, consisting of small-medium sized cells with fine chromatin pattern was seen without epidermotropism which were immunoreactive for CD123, CD56, TdT and CD4, while negative for CD3, CD20, and MPO that confirmed the diagnosis of BPDCN. BPDCN is a highly aggressive hematologic malignancy derived from plasmacytoid dendritic cells. Male-to-female ratio is 3.3:1. Skin involvement can present as either an isolated purplish nodule or disseminated purplish nodules or papules or macules. On microscopic examination, skin involvement is characterized by monomorphic infiltrates of immature neoplastic cells with blastoid morphology, involving the superficial and deep dermis, often with extension into the subcutis with epidermal spare. Immunophenotyping shows usually positive reactions for CD123, CD45, CD4, CD56, TCL1, CD2AP, CD43, BCL2, TdT, Granzyme B, and TCF4, whereas tumor cells are negative for CD3, CD19, CD20, MPO, CD13 and Lysozyme. Differential diagnoses of BPDCN include myeloid sarcoma, myelomonocytic leukemia, mature plasmacytoid dendritic cell proliferation (MPDCP) and Merkel cell carcinoma. Pathologists ought to be familiar with this WHO entity for early disease diagnosis, because of disease rarity and diagnosis difficulties.

METTL3 regulates M6A methylation-modified EBV-pri-miR-BART3-3p to promote NK/T cell lymphoma growth

OBJECTIVE

N6-methyladenosine (M6A) is the most prevalent epigenetic alteration. Methyltransferase-like 3 (METTL3) is a key player in the control of M6A modification. Methyltransferase promote the processing of mature miRNA in an M6A-dependent manner, thereby participating in disease occurrence and development. However, the regulatory mechanism of M6A in NK/T cell lymphoma (NKTCL) remains unclear.

PATIENTS AND METHODS

We determined the expression of METTL3 and its correlation with clinicopathological features using qRT-PCR and immunohistochemistry. We evaluated the effects of METTL3 on NKTCL cells using dot blot assay, CCK8 assay and subcutaneous xenograft experiment. We then applied M6A sequencing combined with gene expression omnibus data to screen candidate targets of METTL3. Finally, we investigated the regulatory mechanism of METTL3 in NKTCL by methylated RNA immunoprecipitation and RNA immunoprecipitation (RIP) assays.

RESULTS

We demonstrated that METTL3 was highly expressed in NKTCL cells and tissues and indicated poor prognosis. The METTL3 expression was associated with NKTCL survival. Functionally, METTL3 promoted the proliferation capability of NKTCL cells in vitro and in vivo. Furthermore, EBV-miR-BART3-3p was identified as the downstream effector of METTL3, and silencing EBV-miR-BART3-3p inhibited the proliferation of NKTCL. Finally, we confirmed that PLCG2 as a target gene of EBVmiR-BART3-3p by relative assays.

CONCLUSIONS

We identified that METTL3 is significantly up-regulated in NKTCL and promotes NKTCL development. M6A modification contributes to the progression of NKTCL via the METTL3/EBV-miR-BART3-3p/PLCG2 axis. Our study is the first to report that M6A methylation has a critical role in NKTCL oncogenesis, and could be a potential target for NKTCL treatment.

A Destructive Midfacial Mass in a Middle-Aged Man

A 43-year-old man presented with a destructive mass on the nose, with multiple areas of erosion, ulcers, and exudate covering the mass. Histological examination showed polymorphous lymphocytic infiltration in the full-thickness dermis. What is your diagnosis?

Analysis of mutation profiles in extranodal NK/T-cell lymphoma: clinical and prognostic correlations

The molecular pathogenesis of extranodal NK/T-cell lymphoma (NKTCL) remains obscured despite the next-generation sequencing (NGS) studies explored on ever larger cohorts in the last decade. We addressed the highly variable mutation frequencies reported among previous studies with comprehensive amplicon coverage and enhanced sequencing depth to achieve higher genomic resolution for novel genetic discovery and comparative mutational profiling of the oncogenesis of NKTCL. Targeted exome sequencing was conducted to interrogate 415 cancer-related genes in a cohort of 36 patients with NKTCL, and a total of 548 single nucleotide variants (SNVs) and 600 Copy number variances (CNVs) were identified. Recurrent amplification of the MCL1 (67%) and PIM1 (56%) genes was detected in a dominant majority of patients in our cohort. Functional mapping of genetic aberrations revealed that an enrichment of mutations in the JAK-STAT signaling pathway, including the cytokine receptor LIFR (copy number loss) upstream of JAK3, STAT3 (activating SNVs), and downstream effectors of MYC, PIM1 and MCL1 (copy number gains). RNA in situ hybridization showed the significant consistence of MCL1 RNA level and copy number of MCL1 gene. We further correlated molecular and clinical parameters with overall survival (OS) of these patients. When correlations were analyzed by univariate followed by multivariate modelling, only copy number loss of LIFR gene and stage (III-IV) were independent prognostic factors of reduced OS. Our findings identified that novel loss of LIFR gene significantly correlated with the adverse clinical outcome of NKTCL patients and provided therapeutic opportunities for this disease through manipulating LIFR.

Extranodal natural killer/T-cell lymphoma with tonsil involvement: a case report

BACKGROUND

Extranodal natural killer/T-cell lymphoma (ENKTL) with tonsil involvement is not common, especially in children.

CASE PRESENTATION

A 13-year-old girl presented with an unexplained sore throat for more than 2 months, together with intermittent fever and suppurative tonsilitis. Nasopharyngoscopy revealed a pharyngeal mass. Enhanced computed tomography (CT) scan showed tonsillar hypertrophy and punctate calcification. Chronic pyogenic granulomatous inflammation with pseudoepithelial squamous epithelial hyperplasia was observed in left tonsil, and pyogenic granulomatous inflammation and a small number of T-lymphoid cells were detected in the right tonsil. The immunohistochemical results showed CD2+, CD3+, CD4+, CD5+, CD8+, granzyme B+, and TIA-1+. The Ki-67 proliferation index was 20%. The case showed T cell receptor gene rearrangement. Finally, the case was diagnosed as ENKTL of stage II with tonsil involvement. The patient received 6 cycles of chemotherapy with SMILE regimen, and showed complete response with no recurrence in the follow-up.

CONCLUSION

We presented a rare case of ENKTL with tonsil involvement in a child. The patient showed complete response to the SMILE chemotherapy with no recurrence.

Clinical epidemiology of Epstein-Barr virus-associated Lymphoproliferative Disorders (EBV-LPDs) in hospitalized children: A six-year multi-institutional study in China

BACKGROUND

Epstein-Barr virus-associated lymphoproliferative disorders (EBV-LPDs) are a group of disorders involving lymphoid tissues or lymphocytes. The epidemiology and economic burden of hospitalized children with EBV-LPDs in China have not been well studied. This study aimed to reveal the epidemic characteristics and disease burden of EBV-LPDs among the Chinese hospitalized children, providing strategies for the prevention and management.

METHODS

This study was based on the FUTang Updating medical REcords (FUTURE) database of China and collected the medical records from 27 tertiary children's hospitals between January 2016 and December 2021 in China, counting five types of EBV-LPDs, namely EBV-positive T-cell lymphoproliferative disease, NK/T cell lymphoma, extranodal NK/T-cell lymphoma (nasal type), systemic EBV-positive T-cell lymphoproliferative disease of childhood and posttransplant lymphoproliferative disorders. We conducted a retrospective syhthesis and analysis of the epidemiological characteristics, expenses, length of stay (LOS), as well as complications among hospitalized children diagnosed with five types of EBV-LPDs and compared parameters using appropriate statistical tests.

RESULTS

The study described 153 children aged 0-18 years hospitalized with EBV-LPDs from 2016 to 2021 in the FUTURE database. The male-to-female ratio was 1.10:1, and more than half of the age distribution was in the 6-12 y group. Among EBV-LPDs cases, EBV+ T-LPD accounted for the largest proportion (65.36%). Complications were presented in 93 children with EBV-LPDs, mainly hemophagocytic lymphohistiocytosis (HLH). The median LOS of NKTL was 26.5 days [interquartile range (IQR) = 3-42], which was the longest among EBV-LPDs. The median hospitalization cost of PTLD was 10 785.74 United States dollars (IQR = 7 329.38-16 531.18), which was the heaviest among EBV-LPDs.

CONCLUSIONS

Compared with the total number of hospitalized children in China during the same period and in the same age group, the proportion of EBV-LPD is very low. EBV-LPD can develop in all age groups, but it is more common in school-age children. Among 5 EBV-LPDs, the disease with the highest proportion is EBV+ T-LPD. The overall disease burden of EBV-LPD was heavy, especially the economic burden. HLH was one of the most common complications, which could directly affect the burden of patients because of prolonged hospitalization. These data are taken from a very large database, illustrating the epidemiological and economic burden of EBV-LPDs hospitalized children in China, which enriched the existing epidemiological and disease burden content of EBV-LPDs.

A lineage-specific STAT5BN642H mouse model to study NK-cell leukemia

ABSTRACT

Patients with T- and natural killer (NK)-cell neoplasms frequently have somatic STAT5B gain-of-function mutations. The most frequent STAT5B mutation is STAT5BN642H, which is known to drive murine T-cell leukemia, although its role in NK-cell malignancies is unclear. Introduction of the STAT5BN642H mutation into human NK-cell lines enhances their potential to induce leukemia in mice. We have generated a mouse model that enables tissue-specific expression of STAT5BN642H and have selectively expressed the mutated STAT5B in hematopoietic cells (N642Hvav/+) or exclusively in NK cells (N642HNK/NK). All N642Hvav/+ mice rapidly develop an aggressive T/NKT-cell leukemia, whereas N642HNK/NK mice display an indolent NK-large granular lymphocytic leukemia (NK-LGLL) that progresses to an aggressive leukemia with age. Samples from patients with NK-cell leukemia have a distinctive transcriptional signature driven by mutant STAT5B, which overlaps with that of murine leukemic N642HNK/NK NK cells. To our knowledge, we have generated the first reliable STAT5BN642H-driven preclinical mouse model that displays an indolent NK-LGLL progressing to aggressive NK-cell leukemia. This novel in vivo tool will enable us to explore the transition from an indolent to an aggressive disease and will thus permit the study of prevention and treatment options for NK-cell malignancies.

Immune profiling of patients with extranodal natural killer/T cell lymphoma treated with daratumumab

Natural killer/T cell lymphoma (NKTCL) is a highly aggressive, heterogeneous non-Hodgkin lymphoma resulting from malignant proliferation of cytotoxic natural killer (NK) or T cells. Previous studies demonstrated variable expression of CD38 on NKTCL tumors. Daratumumab, a human IgGκ monoclonal antibody targeting CD38 with a direct on-tumor and immunomodulatory mechanism of action, was hypothesized to be a novel therapeutic option for patients with relapsed or refractory (R/R) NKTCL. In the phase 2 NKT2001 study (ClinicalTrials.gov Identifier: NCT02927925) assessing the safety and efficacy of daratumumab, a suboptimal overall response rate was seen in R/R NKTCL patients. One patient, whose tumors did not express CD38, responded to treatment, suggesting that the immunomodulatory activities of daratumumab may be sufficient to confer clinical benefit. To understand the suboptimal response rate and short duration of response, we investigated the immune profile of NKTCL patients from NKT2001 in the context of daratumumab anti-tumor activity. Tumor tissue and whole blood were, respectively, analyzed for CD38 expression and patient immune landscapes, which were assessed via cytometry by time-of-flight (CyTOF), multiparameter flow cytometry (MPFC), clonal sequencing, and plasma Epstein-Barr virus (EBV)-DNA level measurements. Changes observed in the immune profiles of NKTCL patients from NKT2001, including differences in B and T cell populations between responders and nonresponders, suggest that modulation of the immune environment is crucial for daratumumab anti-tumor activities in NKTCL. In conclusion, these findings highlight that the clinical benefit of daratumumab in NKTCL may be enriched by B/T cell-related biomarkers.

Artificial intelligence for diagnosis and prognosis prediction of natural killer/T cell lymphoma using magnetic resonance imaging

Accurate diagnosis and prognosis prediction are conducive to early intervention and improvement of medical care for natural killer/T cell lymphoma (NKTCL). Artificial intelligence (AI)-based systems are developed based on nasopharynx magnetic resonance imaging. The diagnostic systems achieve areas under the curve of 0.905-0.960 in detecting malignant nasopharyngeal lesions and distinguishing NKTCL from nasopharyngeal carcinoma in independent validation datasets. In comparison to human radiologists, the diagnostic systems show higher accuracies than resident radiologists and comparable ones to senior radiologists. The prognostic system shows promising performance in predicting survival outcomes of NKTCL and outperforms several clinical models. For patients with early-stage NKTCL, only the high-risk group benefits from early radiotherapy (hazard ratio = 0.414 vs. late radiotherapy; 95% confidence interval, 0.190-0.900, p = 0.022), while progression-free survival does not differ in the low-risk group. In conclusion, AI-based systems show potential in assisting accurate diagnosis and prognosis prediction and may contribute to therapeutic optimization for NKTCL.

A Nomogram Model Based on the Inflammation-Immunity-Nutrition Score (IINS) and Classic Clinical Indicators for Predicting Prognosis in Extranodal Natural Killer/T-Cell Lymphoma

Background

Systemic inflammation, immunity, and nutritional status are closely related to patients' outcomes in several kinds of cancers. This study aimed to establish a new nomogram based on inflammation-immunity-nutrition score (IINS) to predict the prognosis of extranodal natural killer/T-cell lymphoma (ENKTL) patients.

Methods

The clinical data of 435 patients with ENTKL were retrospectively reviewed and randomly assigned to training cohort (n=305) and validation cohort (n=131) at a ratio of 7:3. Cox regression analysis was employed to identify independent prognostic factors and develop a nomogram in the training cohort. Harrell's concordance index (C-index), calibration curve, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA) curve were employed to assess the performance of the nomogram and compare it with traditional prognostic systems (PINK, IPI, KPI). Internal validation was performed using 1000 bootstrap resamples in the validation cohort. Kaplan-Meier survival analyses were conducted to compare the overall survival (OS) of patients in different risk groups.

Results

In the training cohort, in addition to several classic parameters, IINS was identified as an independent prognostic factor significantly associated with the OS of patients. The nomogram established based on the independent prognostic indicators showed superior survival prediction efficacy, with C-index of 0.733 in the training cohort and 0.759 in the validation cohort compared to the PINK (0.636 and 0.737), IPI (0.81 and 0.707), and KPI (0.693 and 0.639) systems. Furthermore, compared with PINK, IPI, and IPI systems, the nomogram showed relatively superior calibration curves and more powerful prognostic discrimination ability in predicting the OS of patients. DCA curves revealed some advantages in terms of clinical applicability of the nomogram compared to the PINK, IPI, and IPI systems.

Conclusion

Compared with traditional prognostic systems, the nomogram showed promising prospects for risk stratification in ENKTL patient prognosis, providing new insights into the personalized treatment.

Assessment of Bone Marrow Involvement in Extranodal NK/T-Cell Lymphoma: Positron Emission Tomography versus Bone Marrow Biopsy, and the Significance of Minimal Involvement by EBV+ Cells (KROG 18-09)

PURPOSE

This study aims to investigate the diagnostic significance of positron emission tomography/computed tomography (PET/CT) in assessing bone marrow (BM) involvement through a comparison of PET/CT findings with BM biopsy in extranodal natural killer/T-cell lymphoma.

MATERIALS AND METHODS

The medical records of 193 patients were retrospectively reviewed. Patients were categorized as having early-stage (PET-ES) or advanced-stage (PET-AS) disease based on PET/CT results. The BM involvement was classified into three groups according to BM biopsy: gross BM involvement, minimal BM involvement (defined as the presence of a limited number of Epstein-Barr virus-positive cells in BM), and no involvement. Calculations of the accuracy of PET/CT in detecting BM involvement and analysis of the clinical outcomes (progression-free survival [PFS] and overall survival [OS]) according to the BM biopsy status were performed.

RESULTS

PET/CT exhibited a sensitivity of 64.7% and a specificity of 96.0% in detecting gross BM involvement. For detecting any (both gross and minimal) BM involvement, the sensitivity was 30.4%, while the specificity was 99.0%. Only one patient (0.7%) demonstrated gross BM involvement among the PET-ES group. Survival outcomes of the PET-ES group with minimal BM involvement (3-year PFS, 55.6%; OS, 77.0%) were closer to those of the PET-ES group with no BM involvement (3-year PFS, 62.2%; OS, 80.6%) than to those of the PET-AS group (3-year PFS, 20.1%; OS, 29.9%).

CONCLUSION

PET/CT exhibits high specificity, but moderate and low sensitivity in detecting gross and minimal BM involvement, respectively. The clinical significance of minimal BM involvement for patients in the PET-ES group may be limited.

Misdiagnosis of lymphoma as vasculitis: A case report

NK/T-cell lymphoma (NKTCL) is a highly aggressive malignant tumour with a very poor prognosis, which often poses diagnostic difficulties due to the non-specificity of its clinical presentation. NK/T-cell lymphoma with eosinophilic hyperplasia syndrome is extremely rare. This article describes a patient with NKTCL misdiagnosed as vasculitis who presented with sinusitis, abdominal pain, anorexia, and lung shadows. Additionally, the patient exhibited extremely high eosinophilia levels, which led to a further misdiagnosis of eosinophilic granuloma. We describe the clinical features, diagnostic methods and differential diagnosis of lymphoma and highlights the importance of a multidisciplinary approach in accurate diagnosis and treatment.

Up-front autologous stem cell transplant in peripheral T-cell lymphoma patients achieving complete response after first-line treatment: A multicentre real-world analysis

We conducted a retrospective, multicentre study to compare consolidation therapy with or without first-line autologous stem cell transplant (ASCT) for peripheral T-cell lymphoma (PTCL) patients in a real-world setting. We enrolled 347 PTCL patients who achieved complete response after first-line treatment. Of these, 257 received consolidation chemotherapy (non-ASCT group) and 90 received ASCT (ASCT group). Clinical outcomes were comparable between ASCT and non-ASCT groups. After propensity score matching, the 2-year cumulative incidence of treatment-related mortality and relapse remained similar between groups (1.9% vs. 2.0%, p = 0.985; 24.7% vs. 47.1%, p = 0.021). However, significant differences emerged in progression-free survival and overall survival probabilities. Within the T-cell lymphoma subgroup, ASCT patients exhibited favourable outcomes compared to non-ASCT patients: 2-year progression-free survival (73.4% vs. 50.8%, p = 0.024) and overall survival (92.1% vs. 73.5%, p = 0.021). Notably, no significant differences were observed for patients with NK/T-cell lymphoma. These real-world data suggest that up-front ASCT is a safe and effective consolidation option for PTCL patients in remission, particularly those with T-cell lymphoma.

An Unusual Presentation of Midline Lethal Granuloma

Extranodal natural killer T-cell lymphoma, nasal type (ENKTCL), is a rare form of non-Hodgkin lymphoma that is strongly related to Epstein-Barr Virus (EBV) infection and commonly presents as "midline lethal granuloma." Herein, we report a middle-aged lady who presented with a two-week history of fever, sore throat and constitutional symptoms. Intraoral examination revealed a lacerated soft palate with an ulcerated uvula. A diagnosis of ENKTCL was confirmed through deep biopsies under general anaesthesia supplemented with a positive serum EBV genome. Unfortunately, she succumbed due to disease progression with left frontal brain metastasis with concurrent pulmonary tuberculosis before treatment was completed. The recommended treatment is multimodality with L-asparaginase-containing regimes chemotherapy in an advanced stage, relapsed, or refractory ENKTCL for better outcomes. The quantification of circulating plasma EBV deoxyribonucleic acid (DNA) is helpful as the baseline of tumour load and a biomarker for monitoring treatment response and prognostication. We advocate repeated and deeper core tissue biopsies.

Characterization of primary small intestinal lymphoma: a retrospective study based on double balloon endoscopy

BACKGROUND

The diagnosis of primary small intestinal lymphoma (PSIL) is difficult. This study aimed to evaluate the clinical, radiological and endoscopic characteristics of PSIL and provide clue for diagnosis.

METHODS

A total of 30 patients diagnosed with PSIL who underwent double balloon endoscopy (DBE) in the First Affiliated Hospital of Zhejiang University were retrospectively analyzed. Clinical, radiological and endoscopic data were collected. Univariate analysis was used to determine significant indicators for differentiating three main subtypes of PSIL. Cox regression analysis was performed to assess the risk factors for survival.

RESULTS

In this study, 10 patients were pathologically diagnosed as diffuse large B-cell lymphoma (DLBCL), 11 were indolent B-cell lymphoma (BCL) and 9 were T-cell lymphoma (TCL). Compared with DLBCL patients, the body mass index (BMI) of TCL patients was significantly lower (p = 0.004). Meanwhile, compared with patients with DLBCL, the patients with indolent BCL had lower levels of C-reactive protein, lactate dehydrogenase (LDH), fibrinogen and D-Dimer (p = 0.004, p = 0.004, p = 0.006, and p = 0.002, respectively), and lower proportion of thicker intestinal wall and aneurysmal dilation in CT scan (p = 0.003 and p = 0.020, respectively). In terms of ulcer morphology, patients with DLBCL had significantly higher proportion of deep ulcers than patients with indolent BCL (p = 0.020, respectively). Cox regression analysis showed that drink (p = 0.034), concomitant colonic ulcers (p = 0.034) and elevated LDH (p = 0.043) are risk factors for mortality in patients with PSIL.

CONCLUSIONS

This study provides clinical characteristics of patients with PSIL. Thicker intestinal wall and aneurismal dilation detected on CT scan and deeper ulcer on DBE examination helps to establish a diagnosis of DLBCL.

Appropriate timing to perform an interim 18F-FDG PET/CT in patients with nasal-type extranodal natural killer/T cell lymphoma

Interim 18F-FDG PET/CT (I-PET) has a role in response evaluation and treatment guidance in patients with nasal-type extranodal natural killer/T cell lymphoma (ENKTL). However, there was no agreement on the timing of I-PET performed, after chemotherapy or after chemoradiotherapy. We aimed to find the appropriate timing for I-PET by assessing the prognostic value of I-PET in response evaluation in ENKTL patients. Two hundred and twenty-seven ENKTL patients who had undergone I-PET were retrospectively included. All patients were grouped based on their therapeutic strategy received, chemotherapy or chemoradiotherapy. The Deauville 5-point score (DS) was used to interpret the I-PET images. The hazard ratio (HR) and C-index were used to measure the discriminatory and prognostic capacities of I-PET performed at different times. One hundred and six patients underwent the I-PET after chemotherapy (chemotherapy group), while I-PET was performed after chemoradiotherapy in 121 patients (chemoradiotherapy group). Eighty-seven patients were classified as metabolic remission (DS score of 1-3), while the other 140 were classified as non-metabolic remission (DS score of 4-5) according to the Deauville criteria. There were no significant survival differences between patients in metabolic remission and in non-metabolic remission in either progression-free survival (PFS, p = 0.406) or overall survival (OS, p = 0.350). In the chemotherapy group, patients in metabolic remission had significantly superior PFS than patients in non-metabolic remission (p = 0.012). For OS, a discriminative trend was also found on the survival curve between patients in metabolic remission and in non-metabolic remission (p = 0.082). In the chemoradiotherapy group, there was no significant difference in PFS (P = 0.185) or OS (P = 0.627) between patients in metabolic remission and in non-metabolic remission. I-PET after chemotherapy yields higher discriminative power and has the ability for prognostic prediction in nasal-type ENKTL patients. I-PET after radiochemotherapy has no prognostic value. Thus, the appropriate timing for I-PET is after chemotherapy but before radiotherapy for response evaluation in nasal-type ENKTL patients.

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.

Histone methyltransferase KMT2D inhibits ENKTL carcinogenesis by epigenetically activating SGK1 and SOCS1

BACKGROUND

Epigenetic alteration plays an essential role in the occurrence and development of extranodal natural killer/T cell lymphoma (ENKTL). Histone methyltransferase (HMT) KMT2D is an epigenetic regulator that plays different roles in different tumors, but its role and mechanism in ENKTL are still unclear.

METHODS

We performed immunohistochemical staining of 112 ENKTL formalin-fixed paraffin-embedded (FFPE) samples. Then, we constructed KMT2D knockdown cell lines and conducted research on cell biological behavior. Finally, to further investigate KMT2D-mediated downstream genes, ChIP-seq and ChIP -qPCR was performed.

RESULTS

The low expression of KMT2D was related to a decreased abundance in histone H3 lysine 4 mono- and trimethylation (H3K4me1/3). In KMT2D knockdown YT and NK-YS cells, cell proliferation was faster (P < 0.05), apoptosis was decreased (P < 0.05), the abundance of S phase cells was increased (P < 0.05), and the level of H3K4me1 was decreased. Notably, ChIP-seq revealed two crucial genes and pathways downregulated by KMT2D.

CONCLUSIONS

KMT2D is a tumor suppressor gene that mediates H3K4me1 and influences ENKTL proliferation and apoptosis by regulating the cell cycle. Moreover, in ENKTL, serum- and glucocorticoid-inducible kinase-1 (SGK1) and suppressor of cytokine signaling-1 (SOCS1) are downstream genes of KMT2D.

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.

EBV DNA methylation profiles and its application in distinguishing nasopharyngeal carcinoma and nasal NK/T-cell lymphoma

BACKGROUND

As an oncovirus, EBV is associated with multiple cancers, including solid tumors and hematological malignancies. EBV methylation plays an important role in regulating tumor occurrence. However, the EBV methylation profiles in EBV-associated tumor tissues are poorly understood.

RESULTS

In this study, EBV methylation capture sequencing was conducted in several different tumor tissue samples, including NPC, EBVaGC, lung LELC and parotid LELC. Besides, EBV capture sequencing and following qMSP were performed on nasopharyngeal brushing samples from NPC and nasal NKTCL patients. Our results showed that the EBV genome among different types of tumors displayed specific methylation patterns. Among the four types of tumors from epithelial origin (NPC, EBVaGC, lung LELC and parotid LELC), the most significant differences were found between EBVaGC and the others. For example, in EBVaGC, all CpG sites within 1,44,189-1,45,136 bp of the EBV genome sequence on gene RPMS1 were hyper-methylated compared to the others. Differently, significant differences of EBV CpG sites, particularly those located on gene BILF2, were observed between NPC and nasal NKTCL patients in nasopharyngeal brushing samples. Further, the methylated level of BILF2 was further detected using qMSP, and a diagnostic model distinguishing NPC and nasal NKTCL was established. The AUC of the model was 0.9801 (95% CI 0.9524-1.0000), with the sensitivity and specificity of 98.81% (95% CI 93.63-99.94%) and 76.92% (95% CI 49.74-91.82%), respectively.

CONCLUSIONS

Our study reveals more clues for further understanding the pathogenesis of EBV, and provides a possibility for distinguishing EBV-related tumor by detecting specific EBV CpG sites.

Targeting CD47-SIRPα axis for Hodgkin and non-Hodgkin lymphoma immunotherapy

The interaction between cluster of differentiation 47 (CD47) and signal regulatory protein α (SIRPα) protects healthy cells from macrophage attack, which is crucial for maintaining immune homeostasis. Overexpression of CD47 occurs widely across various tumor cell types and transmits the "don't eat me" signal to macrophages to avoid phagocytosis through binding to SIRPα. Blockade of the CD47-SIRPα axis is therefore a promising approach for cancer treatment. Lymphoma is the most common hematological malignancy and is an area of unmet clinical need. This review mainly described the current strategies targeting the CD47-SIRPα axis, including antibodies, SIRPα Fc fusion proteins, small molecule inhibitors, and peptides both in preclinical studies and clinical trials with Hodgkin lymphoma and non-Hodgkin 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.

Advances and challenges of immunotherapies in NK/T cell lymphomas

Natural killer (NK)/T cell lymphoma (NKTCL) is a rare subtype of Epstein-Barr virus (EBV)-associated non-Hodgkin lymphoma characterized by poor clinical outcomes. It is more common in East Asian and Latin American countries. Despite the introduction of asparaginase/pegaspargase-based chemotherapy, the prognosis of patients with advanced NKTCL needs to be improved, and few salvage treatment options are available for relapsed/refractory patients who fail chemotherapy. Although many unknowns remain, novel treatment strategies to further improve outcomes are urgently needed. Immunotherapy has emerged and shown favorable antitumor activity in NKTCL, including monoclonal antibodies targeting immune checkpoint inhibitors, other receptors on the cellular membrane, and cellular immunotherapy, which could enhance immune cells attack on tumor cells. In this review, we provide an overview of recent immunotherapy in NKTCL, focusing on programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1), cytotoxic T lymphocyte-associated protein 4 (CTLA-4), chimeric antigen receptor (CAR) T cells, EBV-specific cytotoxic T lymphocytes, immunomodulatory agents, and other targeted agents, as well as the current progress and challenges in the field.

[Extranodal NK/T cell lymphoma, nasal type involving the larynx and digestive tract: a case report and literature review]

Extranodal NK/T cell lymphoma, nasal type（ENKTL） is a highly aggressive malignant tumor derived from NK cells. This article reports a case of ENKTL invading the larynx and digestive tract. The clinical clinical manifestations include hoarseness and intranasal masses.

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).

Intraoral Extranodal Natural Killer Cell/T-Cell Lymphoma of the Hard Palate

Natural killer cell/T-cell lymphoma (NK/TL) is a rare subtype of non-Hodgkin's lymphoma (NHL) associated with the Epstein-Barr virus (EBV) and requires early detection, which can be very challenging. NK/TL often arises in the nasal cavity and can then spread to the oral cavity, but the case presented here is an unusual presentation of NK/TL in a 66-year-old edentulous male patient who initially presented an intraoral exophytic lesion in the palate that appeared within 3 months. We report the present case to highlight the challenges of reaching an accurate diagnosis given the diverse clinical manifestations of NK/TL.

Extranodal natural killer/T-cell lymphoma with hepatosplenic involvement: a retrospective study of a consecutive 14-year case series

Extranodal natural killer/T-cell lymphoma (ENKTL) with hepatosplenic involvement is rare, accounting for approximately 0.2% of ENKTL cases. The clinicopathologic features of ENKTL with hepatosplenic involvement are still poorly understood. Seven cases of ENKTL with hepatosplenic involvement were investigated retrospectively by clinical features, pathology, immunophenotype, genotype, Epstein-Barr virus (EBV) status, and survival analysis. The median age was 36 years; three patients (3/7) had a history of primary nasal ENKTL. Six cases (6/7) presented liver or spleen structures that were replaced by neoplasms, and the neoplastic cells displayed diffuse infiltration; one case (1/7) displayed neoplastic cells scattered in hepatic sinuses and portal areas. The cellular morphology and immunohistochemical features were similar to those of ENKTL involving other sites. Follow-up data were available in five of the seven patients. All five patients received first-line chemotherapy based on L-asparaginase. Three patients died, and two were still alive by the last follow-up. The median overall survival (OS) was 21 months. ENKTL with hepatosplenic involvement is rare, regardless of whether it is initial or secondary. There are two histopathologic patterns of ENKTL with hepatosplenic involvement, and L-asparaginase-based chemotherapy combined with AHSCT might yield good efficacy. Morphological features of ENKTL in the spleen and liver A The architecture of the spleen was affected, and dense infiltration of the neoplastic cells was observed in the left part; B Focal infiltration of the neoplastic cells was located in the red pulp; C Dense infiltration of the neoplastic cells in the liver, accompanied by fatty change of hepatocytes and congestion; D More neoplastic cells accumulated in sinusoidal region.

Extranodal lymphoma: pathogenesis, diagnosis and treatment

Approximately 30% of lymphomas occur outside the lymph nodes, spleen, or bone marrow, and the incidence of extranodal lymphoma has been rising in the past decade. While traditional chemotherapy and radiation therapy can improve survival outcomes for certain patients, the prognosis for extranodal lymphoma patients remains unsatisfactory. Extranodal lymphomas in different anatomical sites often have distinct cellular origins, pathogenic mechanisms, and clinical manifestations, significantly influencing their diagnosis and treatment. Therefore, it is necessary to provide a comprehensive summary of the pathogenesis, diagnosis, and treatment progress of extranodal lymphoma overall and specifically for different anatomical sites. This review summarizes the current progress in the common key signaling pathways in the development of extranodal lymphomas and intervention therapy. Furthermore, it provides insights into the pathogenesis, diagnosis, and treatment strategies of common extranodal lymphomas, including gastric mucosa-associated lymphoid tissue (MALT) lymphoma, mycosis fungoides (MF), natural killer/T-cell lymphoma (nasal type, NKTCL-NT), and primary central nervous system lymphoma (PCNSL). Additionally, as PCNSL is one of the extranodal lymphomas with the worst prognosis, this review specifically summarizes prognostic indicators and discusses the challenges and opportunities related to its clinical applications. The aim of this review is to assist clinical physicians and researchers in understanding the current status of extranodal lymphomas, enabling them to make informed clinical decisions that contribute to improving patient prognosis.