Treatment Outcomes and Prognostic Factors of Chemotherapy Combined With Radiation Therapy for Patients With Early-Stage Extranodal Natural Killer/T-Cell Lymphoma

Purpose

This study aimed to assess the treatment outcomes, toxicity, and potential prognostic factors in patients with early-stage extranodal natural killer/T-cell lymphoma treated with radiation therapy combined with chemotherapy.

Methods and Materials

One hundred eighteen patients with stage I/II extranodal natural killer/T-cell lymphoma who were treated with radiation therapy combined with chemotherapy were retrospectively analyzed between July 2003 and January 2019. The median dose was 50 Gy (Range, 45-61.2 Gy). The Kaplan-Meier method was used to calculate progression-free survival and overall survival. The patients were scored according to their prognostic indices.

Results

The overall and complete response rates were 93.2% and 82.2%, respectively. At a median follow-up of 43 months, the 5-year overall survival and progression-free survival rates were 73.9% and 68.4%, respectively. Adverse events of grade 3 or higher were observed in 20 patients (16.9%). Patients with primary disease in the Waldeyer's ring had poorer survival (P = .015). Compared with anthracycline-based regimens, non-anthracycline-based regimens significantly improved the 5-year overall survival (76.6% vs 54.8%, P = .027) and progression-free survival (72.4% vs 53.1%, P = .013). After treatment, the 5-year overall survival rate was 78.6% in complete response patients versus 44.9% in noncomplete response patients (P = .003). For patients with low- and intermediate-low-risk according to the nomogram-revised risk index model, the complete response rate was 100%. When primary lesion data were added to the nomogram-revised risk index as the basis for another prognostic index (modified nomogram-revised risk index), the low-risk (0 to 2 risk factors) and high-risk (3 or more risk factors) categories were noted (84.2% vs 62.2%, P = .036).

Conclusions

Patients with early-stage extranodal natural killer/T-cell lymphoma had high response rates and favorable survival rates with radiation therapy and non-anthracycline-based chemotherapy regimens. Patients who achieved complete response had better survival than those who did not. The extranodal natural killer/T-cell lymphoma-specific prognostic models may require further optimization.

Mutational characteristics of extranodal NK/T-cell lymphoma analyzed in relation to clinical prognostic indices

Extranodal NK/T-cell lymphoma (ENKTL) is a malignant lymphoma that is associated with Epstein-Barr virus (EBV) infection and poor prognosis. Several clinical risk stratification tools for ENKTL patients have been developed; however, their relationship with molecular alterations of tumor is unclear. We performed panel-based next generation sequencing (NGS) on formalin-fixed paraffin-embedded tissue of 40 ENKTL patients and analyzed them with the clinicopathological features. Patients with over 60 years of age, non-nasal type, stage III-IV, and distant lymph node involvement were 14 (35.0%), 11 (27.5%), 13 (32.5%), and 11 (27.5%), respectively. EBV DNA was detected in the blood of 30 patients (75.0%). In the NGS analysis, mutations involving the JAK/STAT pathway were the most common (n = 17, 42.5%), followed by epigenetic modifier (n = 12, 30.3%), NF-κB pathway (n = 11, 27.5%), tumor suppressor (n = 10, 25.5%), and RAS/MAPK pathway (n = 9, 22.5%). Among these, alterations involving tumor suppressor (P = 0.022) and RAS/MAPK pathway (P = 0.008) were statistically significant poor prognostic factors. Tumor suppressor gene mutations were statistically significantly related to stage III-IV (P = 0.006), distant lymph node involvement (P = 0.002), and prognostic index for natural killer cell lymphoma-EBV (PINK-E) high risk group (P = 0.017). However, alterations involving RAS/MAPK pathway did not significantly correlated with PINK-E or its components. Alterations involving tumor suppressor genes and RAS/MAPK pathway are associated with poor prognosis in ENKTL patients. Tumor suppressor gene mutations are generally correlated with previously known risk factors; however, RAS/MAPK pathway alterations are not.

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.

Optimizing the combination of chemotherapeutic drugs along with radiotherapy for extranodal NK/T-cell lymphoma

Background

Extranodal natural killer/T-cell lymphoma (ENKTCL) has a unique treatment principle. However, the optimal combination of drugs along with radiotherapy (RT) is unknown.

Design

Retrospective cohort study.

Objectives

We screened multiple drug combinations to identify the most efficacious therapeutic combinations.

Methods

We reviewed 3105 patients who received 40 chemotherapy regimens with different combinations of 9 drug classes and/or RT. Least absolute shrinkage and selection operator and multivariable Cox regression analyses were used to screen efficacious single drugs and identify optimal combinations for overall survival (OS). Inverse probability of treatment weighting (IPTW) and multivariable analyses were used to compare survival between treatment regimens.

Results

Screening and validation revealed RT, asparaginase (ASP), and gemcitabine (GEM) to be the most efficacious single modality/drug. RT remained an important component of first-line treatment, whereas ASP was a fundamental drug of non-anthracycline (ANT)-based regimens. Addition of RT to non-ANT-based or ASP/GEM-based regimens, or addition of an ASP-drug into ANT-based or GEM/platinum-based regimens, improved 5-year OS significantly. Use of ASP/GEM-based regimens was associated with significantly higher 5-year OS (79.9%) compared with ASP/ANT-based (69.2%, p = 0.001), ASP/methotrexate-based (63.5%, p = 0.011), or ASP/not otherwise specified-based (63.2%, p < 0.001) regimens. The survival benefit of ASP/GEM-based regimens over other ASP-based regimens was substantial across risk-stratified and advanced-stage subgroups. The survival benefits of a combination of RT, ASP, and GEM were consistent after adjustment for confounding factors by IPTW.

Conclusion

These results suggest that combining ASP/GEM with RT for ENKTCL is an efficacious and feasible therapeutic option and provides a rationale and strategy for developing combination therapies.

Primary cutaneous EBV+ extranodal NK/T-cell lymphoma of gamma/delta T-cell lineage in the posttransplantation setting

Posttransplantation primary cutaneous T-cell lymphomas (PT-CTCL) are a rare complication of sustained immunosuppression in the posttransplant setting. When present, PT-CTCLs are typically EBV- and exhibit features of mycosis fungoides/Sézary syndrome or CD30+ lymphoproliferative disorders. We present a case of a 75-year-old individual who developed skin lesions 30 years after liver transplantation. Pathologic evaluation of the skin biopsy revealed involvement by a clonal, EBV+ T-cell population of gamma/delta lineage with no evidence of systemic disease. Comprehensive genomic profiling was performed, confirming focal one-copy loss of 6q23.3, altogether consistent with the extremely rare and unusual diagnosis of primary cutaneous EBV+ extranodal NK/T-cell lymphoma of gamma/delta T-cell lineage in the posttransplantation setting.

A Case Report of Extranodal NK/T-Cell Lymphoma Misdiagnosed as Meibomitis

INTRODUCTION

Extranodal natural killer/T-cell lymphoma (ENKTL) is a rare type of non-Hodgkin's lymphoma. This report presents a patient with the right lower eyelid ENKTL misdiagnosed as meibomitis repeatedly.

CASE PRESENTATION

A 48-year-old woman developed recurrent redness and swelling in right eyelid for 2 years. Three eyelid mass removal operations were performed in local hospitals, and the pathological examination suggested meibomitis. Physical examination showed an induration in the lateral lower eyelid of the right eye, local defect of the eyelid margin, mild entropion, redness and swelling of the surrounding tissues, and temporal bulbar conjunctiva hyperemia. The eyelid lesion was resected and ENKTL was diagnosed by specific immunohistochemical staining and in situ hybridization. The lymphoma resolved with chemotherapy and radiotherapy. The patient was still alive forty-one months after the last operation.

CONCLUSION

Our report demonstrates that recurrent eyelid redness and swelling might be a malignant tumor, and clinicians should be vigilant.

Challenges in overcoming advanced-stage or relapsed refractory extranodal NK/T-cell lymphoma: meta-analysis of individual patient data

Introduction

Extranodal NK/T-cell lymphoma (ENKTCL), a non-Hodgkin lymphoma, is known for its destructive local impact on nasal structures and systemic induction of inflammatory cytokines. Concurrent treatment with radiation and nonanthracycline- based chemotherapy has improved survival rates in patients with localized disease stages. However, survival outcomes vary significantly in advanced-stage and relapsed or refractory (R/R) cases.

Methods

Therefore, we conducted a meta-analysis using random effects models to assess prognostic factors in advanced or R/R ENKTCL, employing a digital extractor on Kaplan-Meier graphs owing to the scarcity of published prospective trials for these patients.

Results

We observed that patients with advanced ENKTCL treated with Lasparaginase had a median progression-free survival (PFS) of 14.3 months and an overall survival (OS) of 19 months. In R/R ENKTCL, PFS and OS were 11.7 and 15.6 months, respectively. Additionally, OS outcomes in advanced-stage ENKTCL were better in the asparaginase group than that in the non-asparaginase group, with PEG-asparaginase showing superior results compared with that using Lasparaginase. Epstein-Barr Virus (EBV)-DNA positivity in the bloodstream prior to treatment was associated with poor outcomes in advanced-stage ENKTCL, and similar trends were observed in patients with R/R ENKTCL and post-treatment EBV viremia.

Discussion

Collectively, these findings suggest that chemotherapy with Lasparaginase or PEG-asparaginase can enhance survival in advanced or R/R ENKTCL. However, future strategies must be developed to effectively suppress EBV viremia and achieve a deep response toward tumor eradication.

EBV-Positive Nodal T- and NK-Cell Lymphoma Mimicking Anaplastic Large Cell Lymphoma: A Case Report

EBV-positive nodal T- and NK-cell lymphoma (EBV+ NT/NKCL) is a recently recognized entity in the 5th edition of the WHO Classification of Tumors of Hematopoietic and Lymphoid Tissues. Notably, CD30 positivity is frequently observed in (EBV+ NT/NKCL), creating diagnostic challenges to distinguish it from ALK-negative anaplastic large cell lymphoma (ALCL). Furthermore, cases of EBV+ ALCL have been documented in the literature, predating the inclusion of EBV+ nodal cytotoxic T-cell lymphoma as a variant of peripheral T-cell lymphoma. We present a case of a 47-year-old male presenting with multiple lymphadenopathies. The histomorphologic and immunophenotypic features of the lymph node closely resemble ALK-negative ALCL, characterized by uniform CD30 expression and a subcapsular distribution of lymphoma cells. However, the lymphoma cells exhibit diffuse positivity for EBV, consistent with EBV+ NT/NKCL. A case of ALK-negative ALCL with an immunophenotype identical to the EBV-positive case is included for comparison. Given that EBV+ NT/NKCL represents an aggressive neoplasm requiring unique clinical management compared to ALK-negative ALCL, it is critical to accurately differentiate EBV+ NT/NKCL from ALK-negative ALCL with a cytotoxic T-cell immunophenotype.

Sintilimab (anti-PD-1 antibody) plus chidamide (histone deacetylase inhibitor) in relapsed or refractory extranodal natural killer T-cell lymphoma (SCENT): a phase Ib/II study

Anti-PD-1 antibodies are a favorable treatment for relapsed or refractory extranodal natural killer T cell lymphoma (RR-ENKTL), however, the complete response (CR) rate and the duration of response (DOR) need to be improved. This phase 1b/2 study investigated the safety and efficacy of sintilimab, a fully human anti-PD-1 antibody, plus chidamide, an oral subtype-selective histone deacetylase inhibitor in 38 patients with RR-ENKTL. Expected objective response rate (ORR) of combination treatment was 80%. Patients received escalating doses of chidamide, administered concomitantly with fixed-dose sintilimab in 21-days cycles up to 12 months. No dose-limiting events were observed, RP2D of chidamide was 30 mg twice a week. Twenty-nine patients were enrolled in phase 2. In the intention-to-treat population (n = 37), overall response rate was 59.5% with a complete remission rate of 48.6%. The median DOR, progression-free survival (PFS), and overall survival (OS) were 25.3, 23.2, and 32.9 months, respectively. The most common grade 3 or higher treatment-emergent adverse events (AEs) were neutropenia (28.9%) and thrombocytopenia (10.5%), immune-related AEs were reported in 18 (47.3%) patients. Exploratory biomarker assessment suggested that a combination of dynamic plasma ctDNA and EBV-DNA played a vital prognostic role. STAT3 mutation shows an unfavorable prognosis. Although outcome of anticipate ORR was not achieved, sintilimab plus chidamide was shown to have a manageable safety profile and yielded encouraging CR rate and DOR in RR-ENKTL for the first time. It is a promising therapeutic option for this population.

Immunotyping of peripheral blood lymphocytes by flow cytometry reveals Th cell as a potential prognostic biomarker for extranodal NK/T-cell lymphoma

This study aimed to explore the distribution, characteristics and prognostic value of baseline peripheral blood lymphocyte subsets in patients with extranodal NK/T-cell lymphoma (NKTCL). We conducted this cross-sectional study of 205 newly-diagnosed NKTCL patients receiving first-line chemotherapy and radiation at our institute between 2010 and 2020. Baseline peripheral blood lymphocytes were detected using flow cytometry, and the clinical value was analyzed. Compared with healthy controls, patients with NKTCL presented with a distinct peripheral immunity with higher levels of cytotoxic CD8+ T cells (33.230 ± 12.090% vs. 27.060 ± 4.010%, p < 0.001) and NKT cells (7.697 ± 7.219% vs. 3.550 ± 2.088%, p < 0.001) but lower proportions of suppressive regulatory T cells (Treg, 2.999 ± 1.949% vs. 3.420 ± 1.051%, p = 0.003) and CD4+ helper T cells (Th, 33.084 ± 11.361% vs. 37.650 ± 3.153%, p < 0.001). Peripheral lymphocytes were differentially distributed according to age, stage, and primary site in patients with NKTCL. The proportion of Th cells/lymphocytes was associated with tumor burden reflected by stage (p = 0.037), serum lactate dehydrogenase (p = 0.0420), primary tumor invasion (p = 0.025), and prognostic index for NK/T-cell lymphoma (PINK) score (p = 0.041). Furthermore, elevated proportions of T cells (58.9% vs. 76.4%, p = 0.005), Th cells (56.3% vs. 68.8%, p = 0.047), or Treg cells (49.5% vs. 68.9%, p = 0.040) were associated with inferior 5-year progression-free survivals (PFS) via univariable survival analysis. Multivariate cox regression revealed elevated Th cells as an independent predictor for unfavorable PFS (HR = 2.333, 95% CI, 1.030-5.288, p = 0.042) in NKTCL. These results suggested the proportion of Th cells positively correlated with tumor burden and was a potential non-invasive biomarker for inferior survival for patients with 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.

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.

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.

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.

Clinical and prognostic role of sarcopenia based on masticatory muscle index on MR images in patients with extranodal natural killer/T cell lymphoma, nasal type

Sarcopenia is known to be associated with an increased risk of adverse outcomes in a variety of malignancies, but its impact in extranodal natural killer/T cell lymphoma, nasal type (ENKTL-NT) is unknown. The aim of this study was to explore the prognostic relevance of sarcopenia defined by MRI-based masticatory muscle index in ENKTL-NT patients. A total of 112 patients with newly diagnosed ENKTL-NT who underwent cranial magnetic resonance imaging (MRI) were enrolled. The masticatory skeletal muscle index (M-SMI) was measured based on T2-weighted MR images and sarcopenia was defined by M-SMI<5.5 cm2/ m2. The median M-SMI was 5.47 (4.91-5.96) cm2/m2; 58 were identified with sarcopenia in this cohort. On multivariate analyses, sarcopenia was the only independently risk factor predicting overall survival (HR, 4.590; 95% CI, 1.657-12.715; p = 0.003), progression-free survival (HR, 3.048; 95% CI, 1.515-6.130; p = 0.002), and treatment response (HR, 0.112; 95% CI, 0.042-0.301; p < 0.001). In addition, we found that integrating sarcopenia into prognostic indices could improve the discriminative power of the corresponding original model. Stratification analysis showed that sarcopenia was able to further identify survival differences in patients that could not be distinguished by prognostic models. In summary, our study suggests that sarcopenia defined by MRI-based M-SMI represents a new and routinely applicable prognostic indicator of clinical outcome or predictor of treatment response in ENKTL-NT patients, and may aid in risk stratification and treatment decisions.

Comparative analysis of clinicopathologic characteristics and prognosis between nasal and nonnasal extranodal NK/T-cell lymphoma

BACKGROUND

The clinicopathologic characteristics and prognosis of nasal and nonnasal extranodal natural killer T-cell lymphoma (ENKTL) are considered to be different. However, the underlying features responsible for these differences are not well clarified especially in the era of asparaginase therapy.

METHODS

In total, 1007 newly diagnosed ENKTL patients from 11 medical centers were included in this study. Clinicopathologic characteristics and survival data were collected. The chi-squared test and Kruskal-Wallis test were utilized for the comparison of different groups. Univariable and multivariable Cox proportional hazards models were used to screen prognostic factors.

RESULTS

Overall, 869 (86.3%) patients were nasal forms. Compared to patients with nasal ENKTL, nonnasal patients were at more advanced stages and had poor performance status, bone marrow involvement, elevated serum lactate dehydrogenase (LDH), and CD56-negative status (p < 0.05). The 5-year overall survival (OS) for nasal and nonnasal patients were 65.6% and 45.0%, respectively. The OS of nasal forms patients were superior to nonnasal patients, especially in Eastern Cooperative Oncology Group performance status (ECOG PS) (≥2), advanced stage, KPI (HIR/HR), IPI (HIR/HR), PINK (HR), and high EBV DNA load groups. In patients treated with pegaspargase/L-asparaginase-based regimens, the OS of nasal patients was better than that of nonnasal patients. After adjusting the covariates of age, stage, ECOG PS score, LDH, B symptoms, and BM involvement, results showed that the nonnasal site was associated with poor survival of ENKTL.

CONCLUSIONS

The clinicopathologic characteristics and prognosis of nasal and nonnasal ENKTL patients are different. Nasal forms patients had superior OS than nonnasal patients, especially in the era of asparaginase.

Few and far between: clinical management of rare extranodal subtypes of mature T-cell and NK-cell lymphomas

While all peripheral T-cell lymphomas are uncommon, certain subtypes are truly rare, with less than a few hundred cases per year in the USA. There are often no dedicated clinical trials in these rare subtypes, and data are generally limited to case reports and retrospective case series. Therefore, clinical management is often based on this limited literature and extrapolation of data from the more common, nodal T-cell lymphomas in conjunction with personal experience. Nevertheless, thanks to tremendous pre-clinical efforts to understand these rare diseases, an increasing appreciation of the biological changes that underlie these entities is forming. In this review, we attempt to summarize the relevant literature regarding the initial management of certain rare subtypes, specifically subcutaneous panniculitis-like T-cell lymphoma, hepatosplenic T-cell lymphoma, intestinal T-cell lymphomas, and extranodal NK/T-cell lymphoma. While unequivocally established approaches in these diseases do not exist, we make cautious efforts to provide our approaches to clinical management when possible.

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.

Prognostic significance of the systemic immune-inflammation index in patients with extranodal natural killer/T-cell lymphoma

Background

The systemic immune-inflammation index (SII) is based on the neutrophil, platelet, and lymphocyte counts, and has been identified as a prognostic marker in multiple types of cancer. However, the potential value of the SII for predicting survival outcomes in patients with extranodal natural killer/T-cell lymphoma (ENKTCL) has not been investigated thus far.

Method

This study included 382 patients with ENKTCL treated with asparaginase-base regimens from 2021 to 2017 in West China Hospital (Chengdu, China). Clinical and demographic variables, as well as the prognostic value of the SII, were analyzed using Cox proportional hazards regression analysis.

Results

The complete and objective response rates were 55.8% and 74.9%, respectively. Patients with high SII were associated with a lower rate of complete response, higher rate of B symptoms, and serum lactate dehydrogenase levels above or equal to the upper limits of normal (p < 0.01). Patients with low SII were linked to better overall survival and progression-free survival than those with high SII (p < 0.01). Patients with early-stage disease or prognostic model for natural killer lymphoma with Epstein-Barr virus, defined as the low-risk group, could be further stratified according to the SII (p < 0.01). Negative prognostic factors were determined using the Cox proportional hazards regression analysis, which identified four variables: Eastern Cooperative Oncology Group performance status score ≥2, Stage III/IV disease, positivity for Epstein-Barr virus DNA in plasma, and high SII. Predictive nomograms for the prediction of 3- and 5-year overall survival, as well as progression-free survival, were constructed based on those four variables. The nomograms demonstrated favorable discriminating power.

Conclusion

The SII is a novel prognostic marker for ENKTCL, which may be used for the prediction of poorer survival in low-risk patients.

Efficacy of Frontline Chemotherapy for Extranodal Natural Killer/T-Cell Lymphoma: A Systematic Review and Network Meta-Analysis

Background

Treatment with non-anthracycline (ANT)-based chemotherapy has increased survival in patients with extranodal natural killer/T-cell lymphoma (ENKTCL). However, the relative efficacy of various drug combinations has been contentious. We aimed to identify the most effective chemotherapy regimens for newly diagnosed ENKTCL.

Methods

A network meta-analysis was performed to evaluate the differences in survival and treatment responses across various regimens. The primary objective was overall survival (OS), while secondary outcomes included progression-free survival (PFS), objective response rate (ORR), and complete response (CR). We utilized a Bayesian framework to perform the network meta-analysis. Rank probabilities were assessed by the surface under the cumulative ranking curve (SUCRA). Node-splitting method was used to assess the inconsistency.

Results

A total of 1,113 patients were enrolled across 10 studies. Chemotherapy regimens were grouped into five modalities, for which six types of direct comparisons were available. We identified the asparaginase (ASP)/gemcitabine (GEM)-based regimens superiority over ANT-based, non-ASP/ANT-based and ASP/methotrexate (MTX)-based regimens on OS. Although no significant differences were observed compared with ASP/not otherwise specified-based, ASP/GEM-based regimens were still the best option chemotherapy for OS. Moreover, the ASP/GEM-based regimens demonstrated advantages in PFS, ORR and CR.

Conclusions

According to our network meta-analysis, it appears that ASP/GEM-based regimens could potentially serve as the most effective frontline chemotherapy option for ENKTCL.

Outcome and risk prediction of early progression in patients with extranodal natural killer/T cell lymphoma from the CLCG study

Recently, progression-free survival at 24 months (PFS24) was defined as clinically relevant for patients with extranodal NK/T cell lymphoma. Herein, the clinical data from two independent random cohorts (696 patients each in the primary and validation datasets) were used to develop and validate a risk index for PFS24 (PFS24-RI), and evaluate its ability to predict early progression. Patients achieving PFS24 had a 5-year overall survival (OS) of 95.8%, whereas OS was only 21.2% in those failing PFS24 (P<0.001). PFS24 was an important predictor of subsequent OS, independent of risk stratification. The proportion of patients achieving PFS24 and 5-year OS rates correlated linearly among risk-stratified groups. Based on multivariate analysis of the primary dataset, the PFS24-RI included five risk factors: stage II or III/IV, elevated lactate dehydrogenase, Eastern Cooperative Oncology Group score ≥2, primary tumor invasion, and extra-upper aerodigestive tract. PFS24-RI stratified the patients into low-risk (0), intermediate-risk (1-2), high-risk (≥3) groups with different prognoses. Harrell's C-index of PFS24-RI for PFS24 prediction was 0.667 in the validation dataset, indicating a good discriminative ability. PFS24-RI calibration indicated that the actual observed and predicted probability of failing PFS24 agreed well. PFS24-RI provided the probability of achieving PFS24 at an individual patient level.

Prognostic value of post-treatment serum soluble interleukin-2 receptor in newly diagnosed diffuse large B-cell lymphoma patients who achieved complete metabolic response following R-CHOP therapy

Patients with DLBCL achieving complete metabolic response (CMR) after initial treatment with R-CHOP generally have a favourable prognosis; however, there are no established prognostic biomarkers for relapse in these patients. Soluble interleukin-2 receptor (sIL-2R) levels at diagnosis are prognostic factors in patients with DLBCL. However, the significance of post-treatment sIL-2R levels is unclear. To determine the significance of post-treatment serum sIL-2R levels on subsequent relapse and survival, we retrospectively analysed 485 patients with newly diagnosed DLBCL who received R-CHOP treatment and achieved CMR. The cumulative incidence of relapse (CIR) was significantly higher in patients with elevated post-treatment sIL-2R levels than in those with normal sIL-2R levels (five-year CIR; 38.8% vs. 12.8%). The prognostic value remained significant in multivariable analysis (hazard ratio, 2.30; p < 0.001). Five-year progression-free survival (49.0% vs. 83.5%) and overall survival (61.7% vs. 91.6%) rates were lower in patients with elevated post-treatment sIL-2R levels than in those with normal sIL-2R levels (p < 0.001 for both). In patients with newly diagnosed DLBCL who achieved CMR after R-CHOP treatment, the post-treatment serum sIL-2R level was an independent prognostic marker of subsequent relapse and survival.

Targeting Bcl-xL is a potential therapeutic strategy for extranodal NK/T cell lymphoma

Extranodal natural killer/T cell lymphoma, nasal type (ENKTL) is an aggressive lymphoid malignancy with a poor prognosis and lacks standard treatment. Targeted therapies are urgently needed. Here we systematically investigated the druggable mechanisms through chemogenomic screening and identified that Bcl-xL-specific BH3 mimetics effectively induced ENKTL cell apoptosis. Notably, the specific accumulation of Bcl-xL, but not other Bcl-2 family members, was verified in ENKTL cell lines and patient tissues. Furthermore, Bcl-xL high expression was shown to be closely associated with worse patient survival. The critical role of Bcl-xL in ENKTL cell survival was demonstrated utilizing selective inhibitors, genetic silencing, and a specific degrader. Additionally, the IL2-JAK1/3-STAT5 signaling was implicated in Bcl-xL dysregulation. In vivo, Bcl-xL inhibition reduced tumor burden, increased apoptosis, and prolonged survival in ENKTL cell line xenograft and patient-derived xenograft models. Our study indicates Bcl-xL as a promising therapeutic target for ENKTL, warranting monitoring in ongoing clinical trials by targeting Bcl-xL.

PARP inhibitor exerts an anti-tumor effect via LMO2 and synergizes with cisplatin in natural killer/T cell lymphoma

BACKGROUND

PARP inhibitor (PARPi), as a kind of DNA damage repair inhibitor, has been shown to be effective in various solid tumors and hematologic malignancies. Natural killer/T cell lymphoma (NKTCL) is a highly aggressive malignancy, the treatment of which has long been a major challenge in the clinic. Here, we investigated the efficacy and mechanism of PARPi, and the therapeutic value of PARPi combined with cisplatin in NKTCL.

METHODS

The cell proliferation, cell apoptosis, and cell cycle of NKTCL cells were detected respectively by CCK-8 and flow cytometry. The changes of mRNA expression and protein level were measured respectively by mRNA-sequencing, quantitative real-time PCR, western blotting, and immunofluorescence. LMO2 expression was detected by immunohistochemistry and western blotting. Targeted knockdown of LMO2 was conducted by short hairpin RNA. The tumor xenograft models were established to evaluate the efficacy of drugs in vivo.

RESULTS

PARPi inhibited cell proliferation, promoted cell apoptosis, and induced S-phase cell cycle arrest in NKTCL cells. PARPi led to the accumulation of DNA damage by blocking DNA repair and DNA replication. Additionally, LMO2 deficiency reduced the sensitivity of NKTCL cells to PARPi. Finally, the combination of PARPi and cisplatin exhibited significant synergistic effects both in vitro and in vivo.

CONCLUSIONS

In summary, we found that PARPi exerted an anti-tumor effect via LMO2 and synergized with cisplatin in NKTCL, which provides the theoretical basis for the clinical application of PARPi.

Allogeneic hematopoietic stem cell transplantation for NK/T-cell lymphoma: an international collaborative analysis

Natural killer/T-cell lymphomas (NKTCL) represent rare and aggressive lymphoid malignancies. Patients (pts) with relapsed/refractory disease after Asparaginase (ASPA)-based chemotherapy have a dismal prognosis. To better define the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT), we conducted a retrospective analysis of data shared with the European Society for Blood and Marrow Transplantation (EBMT) and cooperating Asian centers. We identified 135 pts who received allo-HSCT between 2010 and 2020. Median age was 43.4 years at allo-HSCT, 68.1% were male. Ninety-seven pts (71.9 %) were European, 38 pts (28.1%) Asian. High Prognostic Index for NKTCL (PINK) scores were reported for 44.4%; 76.3% had >1 treatment, 20.7% previous auto-HSCT, and 74.1% ASPA-containing regimens prior to allo-HSCT. Most (79.3%) pts were transplanted in CR/PR. With a median follow-up of 4.8 years, 3-year progression-free(PFS) and overall survival were 48.6% (95%-CI:39.5-57%) and 55.6% (95%-CI:46.5-63.8%). Non-relapse mortality at 1 year was 14.8% (95%-CI:9.3-21.5%) and 1-year relapse incidence 29.6% (95%-CI:21.9-37.6%). In multivariate analyses, shorter time interval (0-12 months) between diagnosis and allo-HSCT [HR = 2.12 (95%-CI:1.03-4.34); P = 0.04] and transplantation not in CR/PR [HR = 2.20 (95%-CI:0.98-4.95); P = 0.056] reduced PFS. Programmed cell death protein 1(PD-1/PD-L1) treatment before HSCT neither increased GVHD nor impacted survival. We demonstrate that allo-HSCT can achieve long-term survival in approximately half of pts allografted for NKTCL.

Long-term survival by surgery and adjuvant chemotherapy in a patient with perforated extranodal NK/T-cell lymphoma of the small intestine: a retrospective case study

BACKGROUND

Extranodal natural killer/T-cell lymphoma, nasal type (ENKL) of the small intestine, is a disease with extremely poor prognosis. We describe treatment in a case which is novel in that it demonstrated long-term survival.

CASE PRESENTATION

A 68-year-old man was admitted to the emergency department of our hospital with the complaint of severe umbilical pain with tenderness and muscular defense. An abdominal computed tomography scan revealed a thick-wall mass on the small intestine and intra-abdominal free air. He was suspected of perforation of a small intestinal tumor and underwent emergency surgery. The surgery revealed a perforated tumor ulcer, and ENKL was diagnosed from the postoperative pathological findings. The patient's postoperative course was uneventful. He was further treated with adjuvant chemotherapy by hematologist comprising six courses of dexamethasone, etoposide, ifosfamide, and carboplatin. The patient demonstrated long-term survival and was in remission at the time of writing, four years and five months after surgery.

CONCLUSIONS

We report a rare case of long-term survival of perforated ENKL of the small intestine achieved by surgery and adjuvant chemotherapy with dexamethasone, etoposide, ifosfamide, and carboplatin. It is essential to consult with a hematologist to determine the most appropriate chemotherapy such as DeVIC if one encounters rare postoperative pathological findings of ENKL. To elucidate the pathophysiology of this disease and to prolong survival of affected patients, accumulation of cases of long-term survival and examination of associated characteristics is necessary.

Central nervous system involvement at initial diagnosis of extranodal NK/T-cell lymphoma: a retrospective study of a consecutive 12-year case series

Patients with central nervous system (CNS) involvement at initial diagnosis of extranodal NK/T-cell lymphoma (ENKTL) are exceedingly rare, and the clinicopathologic features of CNS involvement have not been well characterized. In this study, we reviewed 662 patients with ENKTL from August 2008 to September 2019. Their clinical and pathological features, treatments, and survival outcomes were analyzed. The median follow-up time was 72 months. Nine of 662 (1.4%) patients were diagnosed with CNS involvement. Among them, the median age was 37 years, and seven patients were male. All patients had positive EBV-DNA, and three patients were asymptomatic at the time of diagnosis with CNS involvement. Common extranodal involved sites included bone, paranasal sinuses, breast, kidney, adrenal gland, and bone marrow. All patients were positive for cytoplasmic CD3ε, cytotoxic granule proteins, and EBER and negative for CD20. All patients received intrathecal chemotherapy and at least one cycle of systemic chemotherapy. Seven patients had died and two were still alive by the last follow-up. The median overall survival (OS) in patients with CNS involvement at initial diagnosis of ENKTL was 9 months, and the 1-year OS was 44.4%. Five patients achieved a complete response after asparaginase-based chemotherapy; two were still alive, one died of systemic progression, one died of ENKTL-associated hemophagocytic syndrome, and one died of treatment-related infections. In conclusion, CNS involvement at initial diagnosis of ENKTL is extremely rare with poor prognosis. There is no standard treatment, and asparaginase-based chemotherapy combined with intrathecal chemotherapy might yield good efficacy.

A controlling nutritional status score is an independent predictor for patients with newly diagnosed nasal-type extranodal NK/T-cell lymphoma based on asparaginase-containing regimens

BACKGROUND

The controlling nutritional status (CONUT) score is a nutritional index that combines serum albumin, total cholesterol, and lymphocyte counts. The potential value of CONUT score for predicting clinical outcomes in patients with nasal-type extranodal NK/T-cell lymphoma (ENKTL) has not been explored.

METHODS

This study included 374 ENKTL patients treated with asparaginase-containing regimens from September 2012 to September 2017. Clinical characteristics, treatment efficacy, prognostic factors, and the predictive value of CONUT score were analyzed.

RESULTS

The complete response (CR) and overall response rate (ORR) were 54.8% and 74.6%, respectively. Patients with CONUT scores <2 had higher CR and ORR compared to patients with scores ≥2 (69.1% vs. 48.9% for CR, p = 0.001; 90.0% vs. 74.6% for ORR, p < 0.001). The 5-year overall survival (OS) and progression-free survival (PFS) rates were 61.9% and 57.3%, respectively. Patients with CONUT scores <2 had better survival outcomes than those with scores ≥2 (5-year OS, 76.1% vs. 56.0%, p < 0.001; 5-year PFS, 74.4% vs. 50.1%, p < 0.001). CONUT score ≥2 was identified as an independent poor prognostic factor for both OS and PFS. A CONUT score ≥2 was also associated with poorer survival outcomes in low-risk ENKTL patients.

CONCLUSION

A CONUT score ≥2 is a prognostic marker for poor survival in patients with ENKTL and could be used to stratify risk in low-risk patients.

Diagnosis and management of rare paediatric Non-Hodgkin lymphoma

Mature B-cell lymphomas, (B- or T-cell) lymphoblastic lymphomas (LBL), and anaplastic large cell lymphoma (ALCL) correspond to about 90% of all non-Hodgkin lymphoma (NHL) cases occurring in children and adolescents. The remaining 10% encompass a complex group of entities characterized by low/very low incidences, paucity of knowledge in terms of underlying biology in comparison to their adult counterparts, and consequent lack of standardization of care, information on clinical therapeutic efficacy and long-term survival. At the Seventh International Symposium on Childhood, Adolescent and Young Adult NHL, organized on October 20-23, 2022, in New York City, New York, US, we had the opportunity to discuss clinical, pathogenetic, diagnostic, and treatment aspects of certain subtypes of rare B- or T-cell NHL and they will be the topic of this review.

Characteristics and prognosis of distant metastasis after primary treatment for early-stage extranodal nasal-type natural killer/T-cell lymphoma from the China Lymphoma Collaborative Group database

This study aimed to investigate the characteristics and prognosis of distant metastasis (DM) after primary treatment for early-stage extranodal nasal-type natural killer (NK)/T-cell lymphoma (ENKTCL). A total of 1619 patients from the China Lymphoma Collaborative Group database were retrospectively reviewed. The cumulative incidence of DM was assessed using Fine and Gray's competing risk analysis. The correlation between DM sites was evaluated using phi coefficients, while DM sites were classified using hierarchical clustering. Regression analysis was used to assess the linear correlation between DM-free survival (DMFS) and overall survival (OS). The 5-year cumulative DM rate was 26.2%, with the highest annual hazard rate being in the first year (14.9%). The most frequent DM sites were the skin and soft tissues (SSTs, 32.4%) and distant lymph nodes (LNs, 31.3%). DM sites were categorized into four subgroups of distinct prognosis - distant LN, SST, extracutaneous site, and lymphoma-associated hemophagocytic lymphohistiocytosis. SST or distant LN, solitary metastasis, and late-onset DM demonstrated a relatively favorable prognosis. Contemporary chemotherapy significantly decreased DM rates and improved DMFS. Decreased DM rates were further associated with increased OS probabilities. Our findings improve the understanding of the variable clinical behaviors of early-stage ENKTCL based on four distinct DM sites and thus provide guidance for future therapeutic decisions, metastatic surveillance, and translational trial design.

Central Nervous System Progression/Relapse in Mature T- and NK-Cell Lymphomas

Non-Hodgkin lymphomas (NHL) are cancers of mature B-, T-, and NK-cells which display marked biological heterogeneity between different subtypes. Mature T- and NK-cell neoplasms are an often-aggressive subgroup of NHL and make up approximately 15% of all NHL. Long-term follow up studies have demonstrated that patients with relapsed/refractory disease have dismal outcomes; in particular, secondary central nervous system (CNS) involvement is associated with higher mortality, though it remains controversial whether this independently confers worse outcomes or if it simply reflects more aggressive systemic disease. Possible risk factors predictive of CNS involvement, such as an elevated lactate dehydrogenase and more than two sites of extranodal involvement, may suggest the latter, though several studies have suggested that discrete sites of anatomic involvement or tumor histology may be independent risk factors as well. Ultimately, small retrospective case series form the basis of our understanding of this rare but devastating event but have not yet demonstrated a consistent benefit of CNS-directed prophylaxis in preventing this outcome. Nonetheless, ongoing efforts are working to establish the epidemiology of CNS progression/relapse in mature T- and NK-cell lymphomas with the goal of identifying clinicopathologic risk factors, which may potentially help discern which patients may benefit from CNS-directed prophylactic therapy or more aggressive systemic therapy.

Risk stratification and prognostic value of multi-modal MRI-based radiomics for extranodal nasal-type NK/T-cell lymphoma

BACKGROUND

Magnetic resonance imaging (MRI) performs well in the locoregional assessment of extranodal nasal-type NK/T-cell lymphoma (ENKTCL). It's important to assess the value of multi-modal MRI-based radiomics for estimating overall survival (OS) in patients with ENKTCL.

METHODS

Patients with ENKTCL in a prospectively cohort were systemically reviewed and all the pretreatment MRI were acquisitioned. An unsupervised spectral clustering method was used to identify risk groups of patients and radiomic features. A nomogram-revised risk index (NRI) plus MRI radiomics signature (NRI-M) was developed, and compared with the NRI.

RESULTS

The 2 distinct type I and II groups of the MRI radiomics signatures were identified. The 5-year OS rates between the type I and type II groups were 87.2% versus 67.3% (P = 0.002) in all patients, and 88.8% versus 69.2% (P = 0.003) in early-stage patients. The discrimination and calibration of the NRI-M for OS prediction demonstrated a better performance than that of either MRI radiomics or NRI, with a mean area under curve (AUC) of 0.748 and 0.717 for predicting the 5-year OS in all-stages and early-stage patients.

CONCLUSIONS

The NRI-M model has good performance for predicting the prognosis of ENKTCL and may help design clinical trials and improve clinical decision making.

Treatment of extranodal NK/T-cell lymphoma: From past to future

Extranodal NK/T-cell lymphoma (ENKTCL) is the most common subtype of T/NK-cell lymphoma in Asia and Latin America, but very rare in North American and Europe. Patient survival has improved significantly over the past two decades. However, standard treatment has not yet been established, although dozens of prospective trials have been conducted. To help understand how the treatment of ENKTCL has evolved in the past and what trends lie ahead, we have comprehensively reviewed the treatment of this aggressive malignancy, with a particular focus on neglected or unanswered issues, such as the optimal staging method, the best partner of asparaginase (Asp), the individualized administration of Asp, the preferred sequence of CT and RT and so on. Overall, the 5-year overall survival (OS) of patients with Ann Arbor stage I/II disease increased from < 50% in the early 20th century to > 80% in recent years, and the median OS of patients with Ann Arbor stage III/IV disease increased from < 1 year to more than 3 years. The improvement in patient survival is largely attributable to advances in radiation technology and the introduction of Asp and anti-PD-1/PD-L1 immunotherapy into practice. Radiotherapy is essential for patients with early-stage disease, while Asp-based chemotherapy (CT) and PD-1/PD-L1 inhibitors significantly improved the prognosis of patients with advanced-stage disease. ENKTCL management is trending toward simpler regimens, less toxicity, and higher efficacy. Novel drugs, such as manufactured T cells, monoclonal antibodies, and small molecule inhibitors, are being intensively investigated. Based on the fact that ENKTCL is highly resistant to cytotoxic drugs except Asp, and aggressive CT leads to higher toxicity rather than better outcomes, we recommend it is unnecessary to expend additional resources to compare different combinations of Asp with cytotoxic agents. Instead, more efforts should be made to optimize the use of Asp and immunotherapy to maximize efficacy and minimize toxicity, explore ways to overcome resistance to Asp and immunotherapy, identify novel treatment targets, and define subpopulations who may benefit more from specific treatments.

A New Prognostic Index for Extranodal Natural Killer/T-Cell Lymphoma:Incorporation of Serum β-2 Microglobulin to PINK

PURPOSE

Prognostic Index for Natural Killer Lymphoma (PINK) is the most widely accepted prognostic model for patients withextranodal natural killer/T-cell lymphoma (ENKTL) treated with non-anthracycline-based therapy. We aimed to evaluate the prognostic implications of serum β-2 microglobulin (β2M) in the context of PINK and proposed a new prognostic model.

MATERIALS AND METHODS

A total of 138 patients who were newly diagnosed with ENKTL and treated with non-anthracycline-based chemotherapy were identified. The cut-off value of high serum β2M was calculated by maximal-chi square methods (4.1 mg/L). A new prognostic model incorporating serum β2M into PINK was proposed and validated in an independent validation cohort (n=88).

RESULTS

The patients' median age was 53.5 years (range, 19 to 80 years). Patients with high serum β2M levels had significantly worse overall survival (OS) and progression-free survival (PFS). In multivariate analysis, high serum β2M was an independent adverse prognostic factor for OS. A new PINK-B (Prognostic Index for Natural Killer Lymphoma-serum β-2 microglobulin) model stratifiedpatients into three groups with distinct OS and PFS in the training cohort (3-year OS, 84.1% [95% confidence interval, 75.1 to 94.2], 46.8% [36.1 to 60.8] and 17.6% [6.3 to 49.2] for the low-, intermediate, and high-risk groups, respectively; 3-year PFS, 70.6% [59.4 to 83.8], 35.9% [25.9 to 49.8], and 7.35% [1.1 to 46.7] for the low-, intermediate-, and high-risk groups, respectively). The PINK-B model was further validated in an independent cohort.

CONCLUSION

Serum β2M is an independent prognostic factor for ENKTL patients. The new serum β2M-based prognostic model may be useful for identifying ultra-high-risk patients, and it can easily be adopted into daily clinical practice.

The value of routine bone marrow examination in patients with extranodal NK/T-cell lymphoma staged with PET/CT

BACKGROUND

Limited evidence supports the omission of routine bone marrow (BM) examination (biopsy and aspiration) in patients with nasal-type extranodal NK/T-cell lymphoma (ENKTCL). This study was aimed at assessing whether BM examination provides valuable information for positron emission tomography/computed tomography (PET/CT)-based staging in this patient population.

PATIENTS AND METHODS

Patients newly diagnosed with ENKTCL who underwent initial staging with both PET/CT and BM examination between 2013 and 2020 were retrospectively identified in two Chinese institutions. Overall, 742 patients were included; the BM examination was positive in 67 patients.

RESULTS

Compared with BM biopsy alone, the combination of BM biopsy and aspiration assessment did not afford any additional diagnostic value. No patient with a positive BM biopsy was found to have early-stage disease by PET/CT. BM biopsy or PET/CT led to upstaging from stage III to IV as a result of BM involvement in 21 patients. In 135 patients with distant organ involvement, BM involvement was associated with worse overall survival (OS) and progression-free survival (PFS) compared with the corresponding durations in patients without BM involvement (2-year OS: 35.9% vs. 60.4%, p < .001; PFS: 26% vs. 40.7%, p = .003). No difference in survival was noted between groups judged positive based on PET/CT and BM biopsy.

CONCLUSION

Compared with aspiration, BM biopsy led to the detection of more BM lesions. Baseline PET/CT can be safely used to exclude BM involvement in early-stage disease. Overall, routine BM examination affords diagnostic or prognostic value over PET/CT in patients with advanced-stage nasal-type ENKTCL.

EBV-associated NK and T-cell lymphoid neoplasms

PURPOSE OF REVIEW

Epstein-Barr virus (EBV)-associated neoplasms derived from natural killer (NK) or T cells comprise a group of clinically and biologically heterogenous disorders affecting children and adults, which are overall rare but more prevalent in Asia and South America. This review focuses on neoplasms presenting in the adulthood, addressing recent genomic discoveries as well as therapeutic developments in these highly aggressive disorders.

RECENT FINDINGS

Distinct molecular subtypes of extranodal NK/T-cell lymphomas (ENKTCLs) have been described, with differences in cell of origin, EBV pattern, genomic alterations, clinical characteristics, response to asparaginase-based therapies and to more recent approaches targeting molecular aberrations of the lymphoma. For the last two decades, progress in the clinical management of ENKTCL was based on L-asapraginase containing combinations and the incoroperation of radiotherapy. A subset of cases with PDL1-2 structural alterations may be more responsive to treatment with immune checkpoint inhibitors. Primary nodal EBV+ lymphomas derived from T or NK cells have distinctive features separating them from both peripheral T-cell lymphoma not otherwise specified and ENKTCL. Treatment algorithms correspond to those for advanced ENKTCL.

SUMMARY

With better understanding of lymphomagenesis, genomic landscape and immunologic aspects of the diseases, future treatment options will include targeted therapies including immune checkpoint inhibitors and novel antibodies.

Integrated driver mutations profile of chinese gastrointestinal-natural killer/T-cell lymphoma

Background

One of the most common nasal external sites in extranodal Natural Killer/T-cell lymphoma (NKTCL) is in the gastrointestinal (GI) system. Despite this, reports on gastrointestinal-Natural Killer/T-cell lymphoma (GI-NKTCL) are very few. To obtain a better understanding of this manifestation of NKTCL, we conducted a retrospective study on GI-NKTCL to analyze its clinical features, genomic changes and immune infiltration.

Methods

We retrospectively collected patients diagnosed with GI-NKTCL in the Sixth Affiliated Hospital of Sun Yat-sen University from 2010 to 2020. From this cohort we obtained mutation data via whole exome sequencing.

Results

Genomic analysis from 15 patients with GI-NKTCL showed that the most common driving mutations were ARID1B(14%, 2/15), ERBB3(14%, 2/15), POT1(14%, 2/15), and TP53(14%, 2/15). In addition, we found the most common gene mutation in patients with GI-NKTCL to be RETSAT(29%, 4/15) and SNRNP70(21%, 3/15), and the most common hallmark pathway mutations to be G2M checkpoint pathway (10/15, 66.7%), E2F targets (8/15, 53.3%), estrogen response late (7/15, 46.7%), estrogen response early (7/15, 46.7%), apoptosis (7/15, 46.7%) and TNFA signaling via NFKB (7/15, 46.7%). In the ICIs-Miao cohort, SNRNP7-wild-type (WT) melanoma patients had significantly prolonged overall survival (OS) time compared with SNRNP7 mutant type (MT) melanoma patients. In the TCGA-UCEC cohort, the patients with RETSAT-MT or SNRNP7-MT had significantly increased expression of immune checkpoint molecules and upregulation of inflammatory immune cells.

Conclusions

In this study, we explored GI-NKTCL by means of genomic analysis, and identified the most common mutant genes (RETSAT and SNRNP70), pathway mutations (G2M checkpoint and E2F targets) in GI-NKTCL patients. Also, we explored the association between the common mutant genes and immune infiltration. Our aim is that our exploration of these genomic changes will aid in the discovery of new biomarkers and therapeutic targets for those with GI-NKTCL, and finally provide a theoretical basis for improving the treatment and prognosis of patients with GI-NKTCL.

Genetic and immunohistochemical profiling of NK/T-cell lymphomas reveals prognostically relevant BCOR-MYC association

Extranodal NK/T-cell lymphoma, nasal type (ENKTL) is an Epstein-Barr virus-positive, aggressive lymphoma with a heterogeneous cell of origin and variable clinical course. Several clinical prognostic indices have been proposed for ENKTL; however, there are few pathological biomarkers. This multi-institutional study sought to identify histologically assessable prognostic factors. We investigated mutation profiles by targeted next-generation sequencing (NGS) and immunohistochemical assessments of expression of MYC, Tyr705-phosphorylated (p-)STAT3, and CD30 in 71 ENKTL samples. The median age of the patients was 66 years (range, 6-100). The most frequent mutations were in STAT3 (27%), JAK3 (4%), KMT2D (19%), TP53 (13%), BCOR (10%), and DDX3X (7%). Immunohistochemistry (IHC) revealed that ENKTLs with STAT3 mutations exhibited higher expression of pSTAT3 and CD30. BCOR mutations were associated with increased MYC expression. Univariate analysis in the entire cohort showed that stage (II, III, or IV), BCOR mutations, TP53 mutations, and high MYC expression (defined as ≥40% positive neoplastic cells) were associated with reduced overall survival (OS). Multivariate modeling identified stage (II, III, or IV) and high MYC expression as independent adverse prognostic factors. In a subgroup analysis of patients treated with anthracycline (AC)-free chemotherapy and/or radiotherapy (RT) with curative intent, BCOR but not high MYC expression was an independent adverse prognostic factor. In conclusion, activating STAT3 mutations are common in ENKTLs and are associated with increased CD30 expression. MYC overexpression is, at least in part, associated with deleterious BCOR mutations, and this BCOR-MYC linkage may have prognostic significance, underscoring the potential utility of IHC for MYC in risk stratification of patients with ENKTL.

How we treat NK/T-cell lymphomas

Natural killer (NK)/T-cell lymphomas are aggressive malignancies with a predilection for Asian and South American populations. Epstein-Barr virus (EBV) infection in lymphoma cells is universal. Predominantly extranodal, NK/T-cell lymphomas are divided clinically into nasal (involving the nose and upper aerodigestive tract), non-nasal (involving the skin, gastrointestinal tract, testes, and other organs), and aggressive leukaemia/lymphoma (involving the marrow and multiple organs) subtypes. Initial assessment should include imaging with positron emission tomography computed tomography (PET/CT), quantification of plasma EBV DNA as a surrogate marker of lymphoma load, and bone marrow examination with in situ hybridization for EBV-encoded small RNA. Prognostication can be based on presentation parameters (age, stage, lymph node involvement, clinical subtypes, and EBV DNA), which represent patient factors and lymphoma load; and dynamic parameters during treatment (serial plasma EBV DNA and interim/end-of-treatment PET/CT), which reflect response to therapy. Therapeutic goals are to achieve undetectable plasma EBV DNA and normal PET/CT (Deauville score ≤ 3). NK/T-cell lymphomas express the multidrug resistance phenotype, rendering anthracycline-containing regimens ineffective. Stage I/II nasal cases are treated with non-anthracycline asparaginase-based regimens plus sequential/concurrent radiotherapy. Stage III/IV nasal, and non-nasal and aggressive leukaemia/lymphoma cases are treated with asparaginase-containing regimens and consolidated by allogeneic haematopoietic stem cell transplantation (HSCT) in suitable patients. Autologous HSCT does not improve outcome. In relapsed/refractory cases, novel approaches comprise immune checkpoint blockade of PD1/PD-L1, EBV-specific cytotoxic T-cells, monoclonal antibodies, and histone deacetylase inhibitors. Future strategies may include inhibition of signalling pathways and driver mutations, and immunotherapy targeting the lymphoma and its microenvironment.

The value of prognostic nutritional index in nasal-type, extranodal natural killer/T-cell lymphoma

Extranodal natural killer/T-cell lymphoma (ENKTL) is an aggressive disorder with heterogeneous clinical characteristics and poor prognosis. The combined value of baseline serum albumin level and absolute peripheral lymphocyte count showed prognostic information in a variety of malignancies, but its evidence is limited in ENKTL. The purpose of this study is to evaluate the impact of prognostic nutritional index (PNI) in ENKTL, and to provide some nutritionally and immunologically relevant information for better risk stratification. We conducted a retrospective study in 533 patients newly diagnosed with ENKTL. The PNI was calculated as albumin (g/L) + 5 × lymphocyte count (10⁹/L). The optimal cutoff values for serum albumin and lymphocyte count were 40.6 g/L and 1.18 × 10⁹/L, respectively, and 47.3 for PNI. After a median follow-up of 70 months, the 5-year overall survival (OS) and progression-free survival (PFS) were 56.2% and 49.5%, respectively. Patients in low PNI group had more unfavorable clinical features, and tended to have worse 5-year OS and PFS compared with those in high PNI group. According PNI-associated prognostic score, patients were classified into different risk groups. Significant difference has been found in 5-year OS and PFS in different risk groups. When PNI and PNI-associated prognostic score were superimposed on the International Prognostic Index (IPI), prognostic index of natural killer lymphoma (PINK), or nomogram-revised risk index (NRI) categories, the PNI and PNI-associated prognostic score provided additional prognostic information. Therefore, PNI and PNI-associated prognostic score could be independent prognostic factors for ENKTL and may be useful for risk stratification and clinical decision-making.

First-line LVDP (L-asparaginase, etoposide, dexamethasone, and cisplatin) regimen combined with radiotherapy is effective for early-stage extranodal natural killer/T-cell lymphoma, nasal type

Chemotherapy combined with radiotherapy could reduce the risk of recurrence in early-stage extranodal NK/T lymphoma (ENKTL). However, the optimal combined chemotherapy regimen is still unknown. Our previous study reported that LVDP (L-asparaginase, etoposide, dexamethasone, and cisplatin) combined with radiotherapy was a potentially effective and safe treatment regimen for early-stage ENKTL. This study further validated the efficacy and safety of LVDP chemotherapy combined with radiation for early-stage ENKTL with more patients and longer follow-up. We retrospectively studied 112 patients with early-stage ENKTL from September 2010 to September 2019. All patients received the LVDP regimen, and 101 of them received radiotherapy. The patients' characteristics, treatment responses, survival outcomes, prognostic factors, and toxicities were analyzed. The median follow-up was 60 months (range, 4 to 117). All patients received median 4 cycles of the LVDP chemotherapy. At the end of therapy, the objective response rate and complete response rate were 88.3% and 77.6%, respectively. The 3- and 5-year OS were 79.6% and 73.2%, and the 3- and 5-year PFS were 75.4% and 71.6%, respectively. Among them, the LVDP regimen combined with radiotherapy yielded more favorable treatment outcomes (the 3-year OS and PFS were 83.1% and 80.8%). The most common severe hematologic toxicity was leukopenia (25% grade 3/4), and the most common severe non-hematologic toxicity was increased transaminase (4.5% grade 3/4). No pancreatitis or treatment-related death occurred. The LVDP regimen combined with radiotherapy had a good therapeutic response and long-term survival with tolerable toxicity for patients with early-stage ENKTL.

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.

[More than a Harmless Cold]

More than a Harmless Cold Abstract. We report on a 54-year-old patient who presented to the general practitioner several times due to a cold with a runny nose and a headache. Despite various therapies the symptoms didn't subside. Further examination showed a nasal NK/T-cell lymphoma stage IV. The patient died despite intensive therapy.

Progress of Hematopoietic Stem Cell Transplantation and Radiotherapy in the Treatment of Extranodal NK/T Cell Lymphoma

Extranodal Natural Killer/T-cell lymphoma (ENKTL) is an extremely rare type of lymphoma which is highly lethal. It mainly affects the midline area unfolding as a necrotic granulomatous and extremely disfiguring lesion. There are two subtypes of (NKTL); the most common one is nasal which appears in the nasal cavity including the nasopharynx, oropharynx, parts of the aero digestive tract and Waldeyer’s ring. While the other rarer subtype, appears in sites like the skin, testis, gastrointestinal tract, salivary glands and muscle. ENKTL is popular for the expression of multidrug resistance-associated P-glycoprotein, which not only plays the main role at exporting many antitumor agents outside tumor cells, but also makes the disease hard to treat. It is commonly associated with Epstein-Barr virus (EBV) infection and commonly occurs in Asian populations. However, there is no single unified consensus yet as to what is the standardized treatment for ENKTL. Radiotherapy alone treatment, has been considered as a first-line therapy for localized ENKTL, which later on was found to be insufficient for improving survival rates. Thus, the combination of chemotherapy and radiotherapy has been recommended as a therapeutic modality for localized ENKTL. Several combination modalities of radiotherapy and chemotherapy have been advised in clinical practice including concurrent, sequential and sandwich chemo radiotherapy. For the best treatment outcome, only patients with localized nasal ENKTL and low risk of treatment failure are eligible for radiotherapy. Both radiotherapy and hematopoietic stem cell transplantation (HSCT) have been used as treatment modalities in ENKTL patients. Upfront HSCT was performed for ENKTL, but it was associated with a very poor prognosis even for the limited-stage disease. The evidence supporting the use of HSCT to treat ENKTL was derived from the results of a series of phase 1 and 2 trials along with retrospective studies. The end result was a unified consensus that consolidative HSCT is not necessary in patients with newly diagnosed localized ENKTL who achieved complete response after treatment with any of the modern chemo radiotherapy regimens. Hence, HSCT is solely advised for advanced and relapsed NKTL. The main debate remains over which HSCT is the most suitable for patients with newly diagnosed advanced NKTL and relapsed NKTL.

Long-term outcomes and central nervous system relapse in extranodal natural killer/T-cell lymphoma

To elucidate the long-term outcomes of non-anthracycline-containing therapies and central nervous system (CNS) events in patients with extranodal NK/T-cell lymphoma, nasal type (ENKTL), the clinical data of 313 patients with ENKTL diagnosed between 2000 and 2013 in a nationwide retrospective study in Japan were updated and analyzed. At a median follow-up of 8.4 years, the 5-year overall survival (OS) and progression-free survival (PFS) were 71% and 64%, respectively, in 140 localized ENKTL patients who received radiotherapy and dexamethasone, etoposide, ifosfamide, and carboplatin (RT-DeVIC) in clinical practice. Nine (6.4%) patients experienced second malignancies. In 155 localized ENKTL patients treated with RT-DeVIC, 10 (6.5%) experienced CNS relapse (median, 12.8 months after diagnosis). In 5 of them, the events were confined to the CNS. Nine of the 10 patients who experienced CNS relapse died within 1 year after CNS relapse. Multivariate analysis identified gingival (HR, 54.35; 95% CI, 8.60-343.35) and paranasal involvement (HR, 7.42; 95% CI, 1.78-30.89) as independent risk factors for CNS relapse. In 80 advanced ENKTL patients, 18 received dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy as first-line treatment. Patients who received SMILE as their first-line treatment tended to have better OS than those who did not (P = 0.071). Six (7.5%) advanced ENKTL patients experienced isolated CNS relapse (median, 2.6 months after diagnosis) and died within 4 months of relapse. No second malignancies were documented in advanced ENKTL patients. In the entire cohort, the median OS after first relapse or progression was 4.6 months. Twelve patients who survived 5 years after PFS events were disease-free at the last follow-up. Of those, 11 (92%) underwent hematopoietic SCT. Our 8-year follow-up revealed the long-term efficacy and safety of RT-DeVIC and SMILE. The risk of CNS relapse is an important consideration in advanced ENKTL. This article is protected by copyright. All rights reserved.

Recent Advances in the Diagnosis and Treatment of Natural Killer Cell Malignancies

Simple Summary

Natural killer (NK)/T-cell lymphomas are aggressive extranodal Epstein–Barr virus (EBV)-positive malignancies. They can be divided into three subtypes: nasal (involving the nose and upper aerodigestive tract), non-nasal (involving skin, gastrointestinal tract, testis and other organs) and disseminated (involving multiple organs). Lymphoma cells are positive for CD3ε, CD56, cytotoxic molecules and EBV-encoded small RNA. There is a predilection for Asian and Central/South American populations. Genome-wide association studies have identified lymphoma susceptibility loci in Asians. Positron emission tomography computed tomography and plasma EBV DNA quantification are crucial at diagnosis and follow-up. Stage I/II patients receive non-athracycline asparaginse-containing regimens, together with sequential/concurrent radiotherapy. Anthracycline-containing regimens are ineffective. Stage III/IV patients receive asparaginase-containing regimens, followed by allogeneic haematopoietic stem cell transplantation (HSCT). Autologous HSCT does not improve outcome. In relapsed/refractory patients, novel approaches include PD1/PD-L1 targeting, EBV-specific cytotoxic T-cells, and monoclonal antibodies. Small molecules including histone deacetylase inhibitors may be beneficial.

Abstract

Natural killer (NK)/T-cell lymphomas are aggressive malignancies. Epstein–Barr virus (EBV) infection in lymphoma cells is invariable. NK/T-cell lymphomas are divided into nasal, non-nasal, and disseminated subtypes. Nasal NK/T-cell lymphomas involve the nasal cavity and the upper aerodigestive tract. Non-nasal NK/T-cell lymphomas involve the skin, gastrointestinal tract, testis and other extranodal sites. Disseminated NK/T-cell lymphoma involves multiple organs, rarely presenting with a leukaemic phase. Lymphoma cells are positive for CD3ε (not surface CD3), CD56, cytotoxic molecules and EBV-encoded small RNA. There is a predilection for Asian and Central/South American populations. Genome-wide association studies have identified lymphoma susceptibility loci in Asian patients. Positron emission tomography computed tomography and plasma EBV DNA quantification are crucial evaluations at diagnosis and follow-up. Stage I/II patients typically receive non-athracycline regimens containing asparaginse, together with sequential/concurrent radiotherapy. Anthracycline-containing regimens are ineffective. Stage III/IV patients are treated with asparaginase-containing regimens, followed by allogeneic haematopoietic stem cell transplantation (HSCT) in suitable cases. Autologous HSCT does not improve outcome. In relapsed/refractory patients, novel approaches are needed, involving PD1/PD-L1 targeting, EBV-specific cytotoxic T-cells, and monoclonal antibodies. Small molecules including histone deacetylase inhibitors may be beneficial in selected patients. Future strategies may include targeting of signalling pathways and driver mutations.

New Approaches for Treatment of Advanced Extranodal NK/T-Cell Lymphoma

Extranodal NK/T cell lymphoma (ENKL) is a rare subtype of lymphoma that shows a poor clinical outcome. The most common sites are the nasal cavity, nasopharynx, paranasal sinuses, tonsils and larynx. Because of P-glycoprotein expression on ENKL cells, ENKL is resistant to anthracycline-based chemotherapy. L-asparaginase-based chemotherapy with or without radiotherapy shows promising outcomes for advanced ENKL, but has limited efficacy in relapsed/refractory ENKL. immune-checkpoint inhibitors, histone deacetylase inhibitors, and monoclonal antibodies are being investigated. In this review, we summarize the new treatments for ENKL.