To evaluate the prognostic value of interim [18F]Fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG PET/CT) after immunotherapy-based systemic therapies in extranodal natural killer/T-cell lymphoma (ENKTL).

We retrospectively recruited 133 newly diagnosed nasal-type ENKTL patients who underwent interim [18F]FDG PET/CT scans after 2-4 cycles of immunotherapy-based treatments. Interim PET/CT was interpreted by maximum standardized uptake value (SUVmax), Deauville 5-point scale (DS), and early treatment response. The prognostic value of overall survival (OS) and progression-free survival (PFS) was assessed with survival curves generated using Kaplan-Meier analysis and compared using the log-rank test. Univariate and multivariate Cox proportional hazards analyses were performed to evaluate the independent effects for survival. Model performance was assessed with a time-dependent area under the curve (time-AUC), concordance index (C-index), and the Akaike information criterion (AIC).

Patients with high SUVmax (> 9.2), DS 5, or with stable disease (SD) or relapsed/progressive disease (PD) on interim PET/CT showed significantly unfavorable OS and PFS with the Kaplan-Meier estimate, respectively. The interim PET/CT parameters remained independent predictors for both OS and PFS after univariate and multivariate analysis. We combined interim DS with the prognostic index for natural killer cell lymphoma-Epstein-Barr virus (PINK-E) model to stratify our cohort into 3 risk categories: low-risk (0-2 risk factors), intermediate-risk (3 risk factors), and high-risk (≥ 4 risk factors), which showed significant and superior stratifications of OS and PFS than PINK-E.

Interim PET/CT after immunotherapy-based systemic treatments showed independent prognostic value for ENKTL. The model combining interim PET/CT with PINK-E might be an effective prognostic tool.

Question The prognostic value of interim [18F]FDG PET/CT in extranodal natural killer/T-cell lymphoma remains uncertain, especially after the introduction of immunotherapy. Findings Deauville 5-point scale on interim [18F]FDG PET/CT after immunotherapy-based systemic therapies was an independent predictor for newly diagnosed extranodal natural killer/T-cell lymphomas. Clinical relevance Interim [18F]FDG PET/CT alone or combined with the prognostic index for natural killer cell lymphoma-Epstein-Barr virus (PINK-E) model is an effective and superior prognostic tool for clinical application in the era of immunotherapy.

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.

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.

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).

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.

Although the host immune response is likely to be important for the prognosis of ENKTL, detailed information on the pre-treatment T lymphocyte subsets in ENKTL is lacking. To improve risk stratification for ENKTL patients, it is essential to look at the prognostic relevance of absolute CD3 + T cell counts (ACD3C), CD4 + T cell counts (ACD4C), and CD8 + T cell counts (ACD8C) for ENKTL. We retrospectively analyzed 46 ENKTL patients in the First Affiliated Hospital of Wenzhou Medical University between December 2016 and June 2022. Kaplan-Meier curves and log-rank tests were used to compare survival rates between groups according to the cut-off values of pre-treatment T lymphocyte subsets. Independent prognostic factors for survival were analyzed by Cox regression. ACD3C, ACD4C, and ACD8C were related to overall survival (OS) and progression-free survival (PFS) in ENKTL patients. Multivariate analyses identified pre-treatment ACD3C, ACD4C, and ACD8C as independent prognostic factors of survival, independent of the International Prognostic Index (IPI), prognostic index of natural killer lymphoma (PINK), and nomogram-revised risk index (NRI). The prognostic models incorporating pre-treatment T lymphocyte subsets and serum lactate dehydrogenase (LDH) could be used to stratify ENKTL patients into different prognostic groups with significantly different survivals. When superimposed on the IPI, PINK, or NRI categories, the ACD3C-LDH, ACD4C-LDH, and ACD8C-LDH models could better identify high-risk patients in the low-risk IPI, PINK, or NRI categories. In conclusion, the pre-treatment ACD3C, ACD4C, and ACD8C are effective prognostic survival indicators in ENKTL patients. When combined with LDH, they could better identify high-risk ENKTL patients.

Radiotherapy is a critical treatment for early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTL) and has yielded favorable survival outcomes. However, their postradiotherapy quality of life (QOL) has not been investigated. Here, we conducted a cross-sectional study to assess the QOL of ENKTL patients with disease-free survival after definitive radiotherapy and to identify factors associated with QOL and treatment optimization.

This cross-sectional study included 310 patients with stage I-II ENKTL of the upper aerodigestive tract (UADT) who had received simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) with a consistent design and achieved disease-free survival. The median postradiotherapy time was 47.2 months (range, 3.1-115.7). The EORTC QLQ-H&N35 questionnaire was used to assess symptom-related QOL, and nine additional items were added to incorporate nasal, optical, and aural-related symptoms. The scores indicate the severity of the symptoms.

The most common postradiotherapy symptoms among patients with ENKTL were nose problems (49.7%), dry mouth (44.8%), tooth problems (41.3%), sensory problems (32.6%), and less sexuality (25.8%). Tooth problems had the highest average score of 18.6, which is still acceptable. The severity of these symptoms decreased over time and reached a plateau in the second year after radiotherapy. Multivariable regression analysis showed that whole-neck irradiation was an independent predictive factor for xerostomia (P = 0.013, OR = 1.114), while age > 60 years was a predictive factor for lower sexuality (P < 0.001, OR = 1.32).

The QOL of patients with early-stage ENKTL after radiotherapy was favorable, and most symptoms improved over time. Radiotherapy was correlated with specific symptoms, which may suggest a direction for further improvement in SIB-IMRT.

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

Retrospective cohort study.

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

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.

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.

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.

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.

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.

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.

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

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.

To investigate the prognostic capacity of baseline 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) metabolic parameters in extranodal natural killer/T-cell lymphoma (ENKTCL), and the influence of relative thresholds (RT) and absolute thresholds (AT) selection on prognostic capacity.

Metabolic tumor volume (MTV)-based parameters were defined using RTs (41 % or 25 % of maximum standardized uptake value [SUVmax]), ATs (SUV 2.5, 3.0, 4.0, or mean liver uptake) in 133 patients. Metabolic parameters were classified into avidity-related parameters (SUVmax, mean SUV [SUVmean], standard deviation of SUV [SUVsd]), volume-related parameters (RT-MTV), and avidity- and volume-related parameters (total lesion glycolysis [TLG] and AT-MTV). The prognostic capacity of the metabolic parameters and the effects of different threshold types (RT vs. AT) were evaluated.

All metabolic parameters were moderately associated with prognosis. However, the area under the receiver operating characteristic curve of MTV and TLG was slightly higher than that of avidity-related parameters for predicting 5-year progression-free survival (PFS) (0.614-0.705 vs. 0.563-0.609) and overall survival (OS) (0.670-0.748 vs. 0.562-0.593). Correlations of MTV and avidity-related parameters differed between RTs (r < 0.06, P = 0.324-0.985) and ATs (r 0.56-0.84, P ≤ 0.001). AT-MTV was the optimal predictor for PFS and OS, while RT-TLG was the optimal predictor for PFS, and the combination of RT-MTV with SUVmax was the optimal predictor for OS.

The incorporation of volume and avidity significantly improved the prognostic capacity of PET in ENKTCL. Composite parameters that encompassed both avidity and volume were recommended.

Low-risk early-stage extranodal natural killer/T-cell lymphoma, nasal type has a favorable outcome with radiation therapy alone, and the addition of chemotherapy shows no survival benefit. Nonetheless, a proportion of patients will relapse or progress, with a dismal outcome, highlighting the need for a novel therapeutic strategy. Promising preliminary findings indicate the efficacy of PD-1/PD-L1 inhibitors in extranodal natural killer/T-cell lymphoma, nasal type, with good toxicity profiles. Here we describe the design of a phase II study (CLCG-NKT-2101), which is evaluating the safety and efficacy of adding anti-PD-1 antibody to the current radiation therapy regimen in low-risk early-stage extranodal natural killer/T-cell lymphoma, nasal type patients. Tislelizumab will be added in an inductive and concurrent way to radiation therapy. The primary end point will be the complete response rate after induction immunotherapy. Clinical trial registration: ClinicalTrials.gov (NCT05149170).

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

The study investigated the treatment and prognosis of advanced-stage extranodal natural killer/T-cell lymphoma (ENKTL). With a median follow-up of 75.03 months, the median overall survival (mOS) for the 195 newly diagnosed stage III/IV ENKTL patients was 19.43 months, and estimated 1-, 2-, 3- and 5-year OS were 59.5%, 46.3%, 41.8% and 35.1%, respectively. Chemotherapy (CT) + radiotherapy (RT) compared to CT alone (P = .007), and hematopoietic stem cell transplantation (HSCT) compared to non-HSCT (P < .001), both improved OS. For patients ≤60 years and ineligible for HSCT, other therapies with complete remission led to comparable OS (P = .141). Nine patients ever treated with chidamide achieved a median progression-free survival (mPFS) and mOS of 53.63 (range, 3.47-92.33) and 54.80 (range, 5.50-95.70) months, and four with chidamide maintenance therapy (MT) achieved a mPFS and mOS of 55.83 (range, 53.27-92.33) and 60.65 (range, 53.70-95.70) months, possibly providing an alternative option for non-HSCT patients. Non-anthracycline (ANT)- compared to ANT-, asparaginase (Aspa)- compared to non-Aspa- and gemcitabine (Gem)- compared to non-Gem-based regimens, prolonged PFS (P = .031; P = .005; P = .009) and OS (P = .010; P = .086; P = .003), respectively. Multivariate analysis demonstrated that Gem-based regimens improved PFS (HR = 0.691, P = .061) and OS (HR = 0.624, P = .037). Gem + Aspa combinations slightly improved PFS and OS compared to regimens containing Gem or Aspa alone (P > 0.05). First-line "intensive therapy," including CT (particularly Gem + Aspa regimens), RT, HSCT and alternative chidamide MT, was proposed and could improve long-term survival for advanced-stage ENKTLs. Ongoing prospective clinical studies may shed further light on the value of chidamide MT.

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.

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.

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.

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.

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.

To investigate the prognostic value of gross tumor volume (GTV) in early-stage extranodal NK/T-cell lymphoma (ENKTCL) treated with intensity-modulated radiation therapy (IMRT) and explore the interactive effect of GTV and radiotherapy (RT) dose on locoregional recurrence (LRR).

The data of 319 early-stage ENKTCL patients who underwent IMRT were reviewed retrospectively. Overall survival (OS), progression-free survival (PFS), and locoregional control (LRC) were estimated using Kaplan-Meier method and compared using the log-rank test. Cox proportional hazards regression was performed to identify independent risk factors for survival outcomes. Penalized spline regression was used to flexibly model the association of continuous predictors (GTV and RT dose) with mortality, progression, and relapse.

The 5-year OS, PFS, and LRC for the entire cohort were 72.9, 64.4, and 89.9%, respectively. The risks of disease mortality, progression, and recurrence increased steadily with increasing GTV. Patients with GTV < 35 mL had significantly higher 5-year OS (83.0% vs. 59.4%; P < 0.001), PFS (76.7% vs. 48.4%; P < 0.001), and lower 5-year cumulative LRR rate (4.9% vs. 14.5%; P = 0.004), than patients with GTV ≥ 35 mL. The risk of LRR was low with RT doses of 50-56 Gy, independent of GTV. For patients with GTV ≥ 35 mL, dose ≥ 56 Gy was not associated with decreased LRR.

Larger GTV is associated with worse survival and higher LRR in early-stage ENKTCL patients treated with IMRT. A dose of 50-56 Gy may be appropriate to achieve lower risk of LRR, regardless of GTV.

Methotrexate, etoposide, dexamethasone, and pegaspargase (MESA) with sandwiched radiotherapy is known to be effective for early-stage extranodal natural killer/T-cell lymphoma, nasal type (NKTCL). We explored the efficacy and safety of reduced-intensity, non-intravenous etoposide, dexamethasone, and pegaspargase (ESA) with sandwiched radiotherapy. This multicenter, randomized, phase III trial enrolled patients aged between 14 and 70 years with newly diagnosed early-stage nasal NKTCL from 27 centers in China. Patients were randomly assigned (1:1) to receive ESA (pegaspargase 2,500 IU/m² intramuscularly on day 1, etoposide 200 mg orally, and dexamethasone 40 mg orally on days 2-4) or MESA (methotrexate 1 g/m² intravenously on day 1, etoposide 200 mg orally, and dexamethasone 40 mg orally on days 2-4, and pegaspargase 2,500 IU/m² intramuscularly on day 5) regimen (four cycles), combined with sandwiched radiotherapy. The primary endpoint was overall response rate (ORR). The non-inferiority margin was -10.0%. From March 16, 2016, to July 17, 2020, 256 patients underwent randomization, and 248 (ESA [n = 125] or MESA [n = 123]) made up the modified intention-to-treat population. The ORR was 88.8% (95% confidence interval [CI], 81.9-93.7) for ESA with sandwiched radiotherapy and 86.2% (95% CI, 78.8-91.7) for MESA with sandwiched radiotherapy, with an absolute rate difference of 2.6% (95% CI, -5.6-10.9), meeting the non-inferiority criteria. Per-protocol and sensitivity analysis supported this result. Adverse events of grade 3 or higher occurred in 42 (33.6%) patients in the ESA arm and 81 (65.9%) in the MESA arm. ESA with sandwiched radiotherapy is an effective, low toxicity, non-intravenous regimen with an outpatient design, and can be considered as a first-line treatment option in newly diagnosed early-stage nasal NKTCL.

Natural killer/T cell lymphoma (NKTCL) is a highly aggressive hematological malignancy. However, there is currently no consensus on therapies for refractory/relapsed patients. In this study, we investigated the synergistic anticancer effect and potential mechanism of combining chidamide, a histone deacetylases (HDACs) inhibitor, and etoposide, a DNA-damaging agent, in NKTCL. We demonstrated that chidamide or etoposide alone dose- and time-dependently inhibited the cell viability of NKTCL cell lines, YT, NKYS and KHYG-1. Functional experiments suggested that combined chidamide and etoposide treatment exerted synergistic antiproliferation effect and enhanced cell apoptotic death in vitro and in vivo. Furthermore, the expression of DNA damage related proteins was detected and we also examined the alternations in histone acetylation, cell cycle progression, and mitochondrial membrane potential (MMP). The results suggested that increased histone acetylation, cell cycle arrest at the G2/M phase and loss of MMP, converging to greater DNA damage, might account for the synergism of the combination of chidamide and etoposide in NKTCL. Taken together, our study provides an evident for possible application on combining HDACs inhibitors and DNA-damaging agents for the treatment of NKTCL.

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.

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.

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.

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.

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

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.

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 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.

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.

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.

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.

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.

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.

We investigated the safety and efficacy profile of intensity-modulated radiation therapy (IMRT) followed by gemcitabine, dexamethasone, cisplatin (GDP), plus chidamide in the first-line setting for intermediate- and high-risk early-stage extranodal natural killer/T-cell lymphoma, nasal type (ENKTCL).

This was an open-label, randomized phase 2 trial performed at two centers in China. Patients were eligible if they were newly-diagnosed with intermediate- and high-risk early-stage ENKTCL with at least one risk factor based on a nomogram-revised risk index:> 60 years old, elevated serum lactate dehydrogenase, invasion of the primary tumor, stage II or Eastern Cooperative Oncology Group performance status > 1 or stage II disease. Patients were treated with IMRT followed by GDP, with or without chidamide, in the first-line setting. Two-year progression-free survival (PFS) comprised the primary endpoint. Toxicities, the 2-year overall survival (OS), and the response rate comprised the secondary endpoints.

Eligible patients (n = 74) were enrolled between May 2015 and December 2019. Among them, 37 patients were treated with IMRT+GDP+chidamide (chidamide group), while 37 cases were treated with IMRT+GDP (control group). Follow-up comprised a median of 43.4 months (range, 1.0-74.6 months). The objective response rate was 86.5% in the chidamide group and 78.4% in the control group (P = 0.359) at the end of treatment completion. The 2-year OS and PFS rates were 89.2% and 75.2% in the chidamide group versus 83.8% (P = 0.388) and 70.2% (P = 0.821) in the control group. The main adverse events were hematological toxicities and mucositis, with similar rates in the two groups (P > 0.05).

The addition of chidamide to IMRT + GDP as first-line treatment achieved similar treatment outcomes and tolerable toxicities in patients with intermediate- and high-risk ENKTCL.

Natural killer/T-cell lymphoma (NKTL) is a sub-type of Epstein-Barr virus (EBV)-related non-Hodgkin lymphomas common in Asia and Latin America but rare elsewhere. Its pathogenesis is complex and incompletely understood. Lymphoma cells are transformed from NK- or T-cells, sometimes both. EBV-infection and subsequent genetic alterations in infected cells are central to NKTL development. Hemophagocytic syndrome is a common complication. Accurate staging is important to predict outcomes but there is controversy which system is best. More than two-thirds of NKTL lympohmas are localized at diagnosis, are frequently treated with radiation therapy only and have 5-year survival of about 70 percent. Persons with advanced NKTLs receive radiation therapy synchronously or metachronously with diverse multi-drug chemotherapy typically including L-asparginase with 5-year survival of about 40 percent. Some persons with widespread NKTL receive chemotherapy only. There are few data on safety and efficacy of high-dose therapy and a haematopoietic cell autotransplant. Immune therapies, histone deacetylase (HDAC)-inhibitors and other drugs are in early clinical trials. There are few randomized controlled clinical trials in NKTLs and no therapy strategy is clearly best; more effective therapy(ies) are needed. Some consensus recommendations are not convincingly evidence-based. Mechanisms of multi-drug resistance are considered. We discuss these issues including recent advances in our understanding of and therapy of NKTLs.

In the multidisciplinary management of early-stage extranodal natural killer/T-cell lymphoma, nasal type (ENKTCL), with curative intent, radiation therapy is the most efficacious modality and is an essential component of a combined-modality regimen. In the past decade, utilization of upfront radiation therapy and non-anthracycline-based chemotherapy has improved treatment and prognosis. This guideline mainly addresses the heterogeneity of clinical features, principles of risk-adapted therapy, and the role and appropriate design of radiation therapy. Radiation therapy methods (including target volume definition, dose and delivery methods) are crucial for optimizing cure for patients with early-stage ENKTCL. The application of the principles of involved site radiation therapy in this lymphoma entity often leads to a more extended clinical target volume (CTV) than in other lymphoma types because it usually presents with primary tumor invasion, multifocal lesions, or extensive submucosal infiltration beyond the macroscopic disease. The CTV varies across different primary sites and is classified mainly into nasal, nonnasal upper aerodigestive tract (UADT), and extra-UADT entities. This review is a consensus of the International Lymphoma Radiation Oncology Group regarding the approach to radiation therapy, target-volume definition, optimal dose, and dose constraints in ENKTCL treatment.

The study aimed to retrospectively analyze the prognosis of patients with stage IE nasal extranodal natural killer/T-cell lymphoma (ENKTL) with dose reduction to clinical target volume (CTV) by using simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT). Forty-four patients were reviewed retrospectively. The prescribed dose was 45 Gy/25 fractions for extended involved-field site and 50-55 Gy/25 fractions for primary tumor site by using SIB-IMRT. The 5-year overall survival (OS), local control (LC) and progression-free survival (PFS) were 81.2%, 93.0%, and 78.8%, respectively. The complete response (CR) rate was 85.4% (37/44). Three patients (6.8%) patients had local failure and 3 (6.8%) patients developed systemic failure. There was only one patient had grade 3 mucositis and 2 patients had grade 3 or grade 4 hematologic toxicities. For patients with stage IE nasal ENKTL, appropriate dose reduction to CTV by SIB-IMRT strategy is feasible and safe with a promising outcome.

This study evaluated the survival benefit of asparaginase (ASP)-based versus non-ASP-based chemotherapy combined with radiotherapy in a real-world cohort of patients with early-stage extranodal nasal-type natural killer/T-cell lymphoma (ENKTCL).

We identified 376 patients who received combined radiotherapy with either ASP-based (ASP, platinum, and gemcitabine; n = 286) or non-ASP-based (platinum and gemcitabine; n = 90) regimens. The patients were stratified into low-, intermediate-, and high-risk groups using the early stage-adjusted nomogram-revised risk index. Overall survival (OS) and distant metastasis (DM)-free survival (DMFS) between the chemotherapy regimens were compared using inverse probability of treatment weighting (IPTW) and multivariable analyses.

ASP-based (versus non-ASP-based) regimens significantly improved 5-year OS (84.5% versus 73.2%, P = 0.021) and DMFS (84.4% versus 74.5%, P = 0.014) for intermediate- and high-risk patients, but not for low-risk patients in the setting of radiotherapy. Moreover, ASP-based regimens decreased DM, with a 5-year cumulative DM rate of 14.9% for ASP-based regimens compared with 25.1% (P = 0.014) for non-ASP-based regimens. The survival benefit of ASP-based chemotherapy and radiotherapy remained consistent after adjusting the confounding variables using IPTW and multivariate analyses; additional sensitivity analyses confirmed these results.

The findings provided support for ASP-based chemotherapy and radiotherapy as a first-line treatment strategy for intermediate- and high-risk early-stage ENKTCL.