MYC overexpression in natural killer cell lymphoma: prognostic and therapeutic implications.

The current clinical management of extranodal natural killer (NK)/T-cell lymphoma (ENKTL) primarily depends on conventional chemotherapy and radiotherapy, underscoring the need for innovative therapeutic strategies. This study explores the clinical significance and therapeutic implication of c-MYC (MYC) in ENKTL. Initially, we identified MYC protein overexpression in approximately 75% of cases within a large cohort of 111 patients. MYC overexpression was strongly correlated with lymphoma cell proliferation and poor clinical outcomes. Intriguingly, integrating MYC expression into the prognostic index of NK cells lymphoma with Epstein-Barr virus (PINK-E) prognostic model significantly enhanced its predictive power. Subsequently, we implemented MYC knockdown in NK malignancy cell lines with MYC overexpression, resulting in significant viability reduction. RNA sequencing used to determine MYC function revealed a high overlap with canonical MYC-regulated genes and enrichment in metabolism and cell cycle regulation. Integrative analysis of the RNA-sequencing data upon MYC knockdown with gene expression profiles of primary ENKTL cases identified a subset of genes closely associated with MYC overexpression. Among these, CDK4 emerged as a potential therapeutic target, and its inhibition not only abrogated MYC function but also decreased MYC expression in NK malignancy cells. Furthermore, the clinical-grade CDK4/6 inhibitor palbociclib exhibited a potent anti-tumor effect in xenograft mouse models, especially when combined with gemcitabine. In summary, our study firmly establishes MYC as an oncogene with prognostic significance in ENKTL and highlights CDK4 inhibition as a promising therapeutic strategy for treating ENKTL with MYC overexpression.

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

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

Clinicopathological analysis of immunohistochemical CD47 and signal-regulatory protein-α expression in Extranodal Natural killer/T-cell lymphoma.

BACKGROUND: The interaction between CD47 and signal-regulatory protein-alpha (SIRPα) inhibits phagocytosis, and their clinicopathological characteristics have been evaluated in various diseases. However, the significance of CD47 and SIRPα expression, as well as the combined effect, in Extranodal Natural killer/T-cell Lymphoma (ENKTL) remains uncertain. METHODS: In total, 76 newly diagnosed ENKTL patients (mean age 49.9 years, 73.7% male) were included in this study. CD47 and SIRPα expression were examined by immunohistochemistry. Survival analyses were conducted through Kaplan-Meier curves and the Cox regression model. RESULTS: Seventy-one (93.4%) cases were categorized as the CD47 positive group and 59 (77.6%) cases were categorized as the SIRPα positive group. CD47-negative cases had more advanced-stage illness (P = 0.001), while SIRPα-positive cases showed significantly lower levels of high-density lipoprotein (P < 0.001). In univariable analysis, CD47, SIRPα expression, and their combination were significantly associated with prognosis (P < 0.05). In multivariable analysis, only positive SIRPα expression remained significantly associated with superior overall survival (Hazard ratio [HR] 0.446; 95% confidence interval [CI] 0.207-0.963; P = 0.004). Furthermore, SIRPα expression could re-stratify the survival of patients in ECOG (< 2), advanced CA stage, PINK (HR), CD38-positive, PD1-positive, and CD30-positive groups. CONCLUSIONS: SIRPα status was a potential independent prognostic factor for ENKTL. The prognostic significance of CD47 expression and the interaction between CD47 and SIRPα in ENKTL need further investigation.

A novel prognostic index for extranodal natural killer/T-cell lymphoma in the era of pegaspargase/L-asparaginase.

Aim: This multicenter retrospective study aimed to develop a novel prognostic system for extranodal natural killer/T-cell lymphoma (ENKTL) patients in the era of pegaspargase/L-asparaginase.Materials & methods: A total of 844 newly diagnosed ENKTL patients were included.Results: Multivariable analysis confirmed that Eastern Cooperative Oncology Group performance status, lactate dehydrogenase, Chinese Southwest Oncology Group and Asia Lymphoma Study Group ENKTL (CA) system, and albumin were independent prognostic factors. By rounding up the hazard ratios from four significant variables, a maximum of 7 points were assigned. The model of Huaihai Lymphoma Working Group-Natural killer/T-cell Lymphoma prognostic index (NPI) was identified with four risk groups and the 5-year overall survival was 88.2, 66.7, 54.3 and 30.5%, respectively.Conclusion: Huaihai Lymphoma Working Group-NPI provides a feasible stratification system for patients with ENKTL in the era of pegaspargase/L-asparaginase.

[Box: see text].

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

Current prognostic scoring systems based on clinicopathologic variables are inadequate in predicting the survival and treatment response of extranodal natural killer/T-cell lymphoma (ENKTL) patients undergoing nonanthracyline-based treatment. We aimed to construct a classifier based on single-nucleotide polymorphisms (SNPs) for improving predictive accuracy and guiding clinical decision making. Data from 722 patients with ENKTL from international centers were analyzed. A 7-SNP-based classifier was constructed using LASSO Cox regression in the training cohort (n = 336) and further validated in the internal testing cohort (n = 144) and in 2 external validation cohorts (n = 142 and n = 100). The 7-SNP-based classifier showed good prognostic predictive efficacy in the training cohort and the 3 validation cohorts. Patients with high- and low-risk scores calculated by the classifier exhibited significantly different progression-free survival (PFS) and overall survival (OS) (all P < .001). The 7-SNP-based classifier was further proved to be an independent prognostic factor by multivariate analysis, and its predictive accuracy was significantly better than clinicopathological risk variables. Application of the 7-SNP-based classifier was not affected by sample types. Notably, chemotherapy combined with radiotherapy significantly improved PFS and OS vs radiotherapy alone in high-risk Ann Arbor stage I patients, whereas there was no statistical difference between the 2 therapeutic modalities among low-risk patients. A nomogram was constructed comprising the classifier and clinicopathological variables; it showed remarkably better predictive accuracy than either variable alone. The 7-SNP-based classifier is a complement to existing risk-stratification systems in ENKTL, which could have significant implications for clinical decision making for patients with ENKTL.

GELAD chemotherapy with sandwiched radiotherapy for patients with newly diagnosed stage IE/IIE natural killer/T-cell lymphoma: a prospective multicentre study.

Early-stage natural killer/T-cell lymphoma (NK/TCL) patients usually receive a combination of chemotherapy and radiotherapy, but the optimal treatment approach has not yet been established. This study aimed to investigate the efficacy and safety profile of a novel chemotherapy regimen and sandwiched radiotherapy in early-stage NK/TCL. Patients with newly diagnosed stage IE/IIE disease were eligible. Patients were initially treated with two courses of the GELAD regimen (gemcitabine 1·0 g/m2 day 1, etoposide 60 mg/m2 days 1-3, pegaspargase 2000 units/m2 day 4, and dexamethasone 40 mg days 1-4), followed by intensity-modulated radiotherapy (IMRT; 50-56 Gy in 25-28 fractions) and two additional courses of GELAD chemotherapy. A total of 52 patients were enrolled. The overall response rate and complete response rate per Lugano 2014 criteria were 94·2% and 92·3% respectively. With a median follow-up of 32 months, the estimated four-year overall survival rate and progression-free survival rate were 94·2% [95% confidence interval (CI), 83·2% to 93·1%] and 90·4% (95% CI, 78·4% to 95·9%) respectively. The most common adverse events were related to pegaspargase. Haematological toxicities were mild, with grade 3/4 neutropenia in 15·4% of patients. Our study provides a new approach with high activity and improved safety for the treatment of early-stage NK/TCL patients. This study was registered at www.clinicaltrials.gov as NCT02733458.

Avelumab for the treatment of relapsed or refractory extranodal NK/T-cell lymphoma: an open-label phase 2 study.

This study aimed to assess the efficacy and safety of treatment with avelumab, an anti-programmed death ligand 1 (PD-L1) antibody, in patients with relapsed or refractory extranodal natural killer/T-cell lymphoma (ENKTL). In this phase 2 trial, 21 patients with relapsed or refractory ENKTL were treated with 10 mg/kg of avelumab on days 1 and 15 of a 28-day cycle. The primary end point was the complete response (CR) rate based on the best response. Targeted sequencing and immunohistochemistry were performed using pretreatment tumor tissue, and blood samples were drawn before and after treatment for measurement of cytokines and soluble programmed cell death protein 1 (PD1), PD-L1, and PD-L2. The CR rate was 24% (5 of 21), and the overall response rate was 38% (8 of 21). Although nonresponders showed early progression, 5 responders currently continue to receive treatment and have maintained their response. Most treatment-related adverse events were grade 1 or 2; no grade 4 adverse events were observed. Treatment responses did not correlate with mutation profiles, tumor mutation burden, serum levels of cytokines, or soluble PD1/PD-L1 and PD-L2. However, the response to avelumab was significantly associated with the expression of PD-L1 by tumor tissue (P = .001). Therefore, all patients achieving CR showed high PD-L1 expression, and their tumor subtyping based on PD-L1 expression correlated with treatment response. In summary, avelumab showed single-agent activity in a subset of patients with relapsed or refractory ENKTL. The assessment of PD-L1 expression on tumor cells might be helpful for identifying responders to avelumab. This trial was registered at www.clinicaltrials.gov as #NCT03439501.

Prognostic value of 25-hydroxy vitamin D in extranodal NK/T cell lymphoma.

25-hydroxy vitamin D [25-(OH)D] is widely used to determine vitamin D status in clinic. The aim of our study was to evaluate the prognostic value of 25-(OH)D in extranodal NK/T cell lymphoma (ENKTL). Ninety-three (93) ENKTL patients with available serum 25-(OH)D values were enrolled in our study. Vitamin D deficiency is defined as a 25-(OH)D below 50 nmol/L (20 ng/ml). Univariate and multivariate regression analyses were performed to determine independent risk factors for progression-free survival (PFS) and overall survival (OS). Receiver operator characteristic (ROC) curves were plotted, and corresponding areas under the curves (AUC) were calculated to estimate the accuracy of PINK-E (prognostic index of natural killer lymphoma added with Epstein-Barr virus-DNA status) and 25-(OH)D deficiency in ENKTL risk-stratification. Our results suggested that the vitamin D deficiency was an independent inferior prognostic factor for both PFS [hazard ratio (HR), 2.869; 95% confidence interval (CI), 1.540 to 5.346; P = 0.003] and OS (HR, 3.204; 95% CI, 1.559 to 6.583; P = 0.006) in patients with ENKTL. Additionally, we demonstrated that adding 25-(OH)D deficiency to PINK-E score system indeed has a superior prognostic significance than PINK-E alone for PFS [AUC: 0.796 (95% CI: 0.699 to 0.872) vs. 0.759 (95% CI: 0.659 to 0.841), P = 0.020] and OS [AUC: 0.755 (95% CI: 0.655 to 0.838) vs. 0.721 (95% CI: 0.618 to 0.809), P = 0.040]. In conclusion, our study proved that 25-(OH)D deficiency was associated with inferior survival outcome of ENKTL patients.

Dynamic evaluation of the prognostic value of 18F-FDG PET/CT in extranodal NK/T-cell lymphoma, nasal type.

Extranodal natural killer/T-cell lymphoma, nasal-type (ENKTL) is a type of rare and distinct entity of non-Hodgkin lymphoma with poor prognosis. It is important to evaluate the early treatment response accurately to decide further treatment strategy. 18F-FDG PET/CT plays an important role in response evaluation and prognostic prediction in some kinds of lymphomas. However, data available regarding patients with ENKTL are limited. Thus, in this prospective study, we analyzed the prognostic value of 18F-FDG PET/CT in ENKTL. Thirty-four patients with newly diagnosed ENKTL were enrolled in this phase 2 study (NCT02825147, July 7, 2016). The patients received pre-, mid-, and end-treatment 18F-FDG PET/CT scans. Deauville score (DS), maximal standardized uptake values (SUVmax), and the change in SUVmax (ΔSUVmax) were recorded for response assessment. The median follow-up period was 42.2 months. The 2-year overall survival (OS) and progression-free survival (PFS) were 82.4% and 73.5%, respectively. Univariate analysis revealed that Ann Arbor stage (P < 0.002), mid-treatment DS (P = 0.005), mid-SUVmax (P = 0.001), mid-∆SUVmax (P = 0.004), end-treatment DS (P < 0.001), and end-SUVmax (P = 0.014) were prognostic factors for OS. Ann Arbor stage (P = 0.001), mid-treatment DS (P = 0.008), mid-SUVmax (P = 0.029), mid-∆SUVmax (P < 0.001), and end-treatment DS (P =0.021) were of prognostic significance for PFS. Multivariate analysis showed that mid-SUVmax (P = 0.042) and DS at the middle (P = 0.050) and end (P = 0.044) of treatment were significant independent predictors of PFS. 18F-FDG PET/CT is useful for predicting the prognosis of ENKTL.

High infiltration of CD20+ B lymphocytes in extranodal natural killer/T-cell lymphoma is associated with better prognosis.

Immune cells have an uncertain function during the progression of extranodal natural killer/T-cell lymphoma (ENKTL). The present study determined the distribution, phenotype, and clinical significance of B lymphocytes in ENKTL. Immunohistochemistry indicated high infiltration of CD20+ B lymphocytes in the tumour tissues of 40% of the patients, and that a high infiltration correlated with better overall survival. Moreover, B lymphocytes had an active mature phenotype in situ and suppressed the proliferation of ENKTL cells in vitro. These results suggest that tumour infiltration of CD20+ B lymphocytes may be a new prognostic indicator for patients with ENKTL.

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

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

Risk-based, response-adapted therapy for early-stage extranodal nasal-type NK/T-cell lymphoma in the modern chemotherapy era: A China Lymphoma Collaborative Group study.

We aimed to determine the survival benefits of chemotherapy (CT) added to radiotherapy (RT) in different risk groups of patients with early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL), and to investigate the risk of postponing RT based on induction CT responses. A total of 1360 patients who received RT with or without new-regimen CT from 20 institutions were retrospectively reviewed. The patients had received RT alone, RT followed by CT (RT + CT), or CT followed by RT (CT + RT). The patients were stratified into different risk groups using the nomogram-revised risk index (NRI). A comparative study was performed using propensity score-matched (PSM) analysis. Adding new-regimen CT to RT (vs RT alone) significantly improved overall survival (OS, 73.2% vs 60.9%, P < .001) and progression-free survival (PFS, 63.5% vs 54.2%, P < .001) for intermediate-risk/high-risk patients, but not for low-risk patients. For intermediate-risk/high-risk patients, RT + CT and CT + RT resulted in non-significantly different OS (77.7% vs 72.4%; P = .290) and PFS (67.1% vs 63.1%; P = .592). For patients with complete response (CR) after induction CT, initiation of RT within or beyond three cycles of CT resulted in similar OS (78.2% vs 81.7%, P = .915) and PFS (68.2% vs 69.9%, P = .519). For patients without CR, early RT resulted in better PFS (63.4% vs 47.6%, P = .019) than late RT. Risk-based, response-adapted therapy involving early RT combined with CT is a viable, effective strategy for intermediate-risk/high-risk early-stage patients with ENKTCL in the modern treatment era.

Programmed Cell Death 1 and Programmed Cell Death Ligands in Extranodal Natural Killer/T Cell Lymphoma: Expression Pattern and Potential Prognostic Relevance.

The programmed cell death 1/programmed cell death ligands (PD-1/PD-Ls) axis is a potential immune escape mechanism of cancers. However, data on the PD-1/PD-Ls pathway in EBV-associated extranodal natural killer/T cell lymphoma (ENKTL) and its clinical implication are limited. Herein, we characterized PD-1/PD-L expression and its prognosis relevance in 49 ENKTL patients in Thailand. PD-L1 was expressed frequently on both lymphoma cells (61.2%) and stroma (77.5%), whereas PD-L2 expression was more common on lymphoma (63.2%) than stromal cells. PD-1 was positive in 20.5% of stroma, but undetectable on lymphoma cells. There was no association between baseline clinical characteristics and the expression PD-1/PD-Ls. The survival of patients with PD-Ls on tumor cells was poor. For PD-L1-positive versus negative cases, the 2-year event-free survival (EFS) was 42.2 versus 71.8% (p = 0.03) and 2-year overall survival (OS) was 45.4 versus 78.9% (p = 0.02), respectively. Comparing between patients with PD-L2-positive and PD-L2-negative lymphoma, the 2-year EFS was 37.1 versus 82.4% (p = 0.02) and 2-year OS was 45.2 versus 82.4% (p = 0.03), respectively. Neither PD-1 nor PD-Ls expression in the stroma predicted outcomes. In conclusion, PD-Ls were frequently expressed on ENKTL cells and associated with inferior outcomes. Therefore, PD-Ls are potential prognostic biomarkers and the roles of immune checkpoint blockade therapy in ENKTL deserve further investigation.

Treatment and prognosis of mature (non-anaplastic) T- and NK-cell lymphomas in childhood, adolescents, and young adults.

Paediatric non-Hodgkin lymphomas (pNHL) are a diverse group of malignancies characterised by nodal and/or extranodal involvement. Less common pNHL forms include those derived from mature T- and natural killer (NK) cells. Much of our current understanding of paediatric mature (non-anaplastic) T/NK-cell lymphomas with respect to pathogenesis, diagnosis and treatment is extrapolated from adult literature. At the Sixth International Symposium on Childhood, Adolescent and Young Adult Non-Hodgkin Lymphoma, convened September 26-29, 2018 in Rotterdam, The Netherlands, some important aspects on diagnosis and outcomes of mature (non-anaplastic) T/NK-cell lymphoma in children and adolescents were discussed and will be reviewed in here.

Mature (non-anaplastic, non-cutaneous) T-/NK-cell lymphomas in children, adolescents and young adults: state of the science.

Mature (non-anaplastic) T-cell and natural killer (NK)-lymphomas rarely occur in children or adolescents. Due to the low incidence and heterogeneity, information regarding the aetiology, physiopathology and genetics of paediatric mature (non-anaplastic) T/NK-cell lymphoma is lacking. In addition, standard treatments have not yet been established. In the absence of randomised clinical trials, anthracycline-containing regimens are usually considered as the first treatment option, but with discouraging outcomes, especially in patients with advanced disease. The implementation of autologous or allogeneic stem cell transplantation as upfront consolidation therapy or for chemotherapy-sensitive relapsed disease have resulted in improved survival for some patient subsets. The recent use of novel targeted molecular and immunotherapeutic agents has also been shown to be promising in small numbers of patients. In this context, we will review the current state of the scientific knowledge on the most common mature (non-anaplastic, non-cutaneous) T/NK-cell lymphomas occurring in children, adolescent and young adults.

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

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

Improved prognosis of extranodal NK/T cell lymphoma, nasal type of nasal origin but not extranasal origin.

Extranodal NK/T cell lymphoma (NKTCL), nasal type (ENKL) that shows no apparent nasal involvement, is termed extranasal NKTCL or non-nasal NKTCL. In this study, we aimed to explore therapeutic approaches and outcomes in patients with extranasal NKTCL in current clinical practice. A data set of patients with newly diagnosed NKTCL who were diagnosed at 31 institutes in Japan between 2000 and 2013 was used for analysis. The patients' fitness for steroid, methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy was assessed using the major inclusion criteria of the SMILE phase 2 study. Of 358 patients, 47 (13%) had extranasal NKTCL. The most frequent extranodal sites of involvement in extranasal NKTCL were skin/subcutaneous tissue (n = 18). Six (13%) of the patients with extranasal NKTCL had localized disease and were diagnosed before 2010. With a median follow-up of 5.8 years, the 2-year overall survival (OS) in patients with nasal and extranasal NKTCL was 70% (95% confidence interval [CI], 65-75%) and 34% (95% CI, 21-47%), respectively. OS in patients with nasal NKTCL had a trend toward better according to treatment era (P = 0.063). In contrast, no obvious improvement of OS was observed in extranasal NKTCL (P = 0.43). The major inclusion criteria of the SMILE-P2 were met in 21% (10/47) of patients with extranasal NKTCL and 60% (188/311) of those with nasal NKTCL (P < 0.001). Despite the advent of new treatments for ENKL, OS remains unfavorable in extranasal NKTCL. A more effective therapy is needed for extranasal NKTCL.

[Clinical differences between primary nasopharyngeal NK/T-cell lymphoma and primary nasal cavity NK/T-cell lymphoma with nasopharynx extension].

Objective: To investigate the clinical and prognostic differences between primary nasopharyngeal natural killer (NK)/T-cell lymphoma (NP NKTCL) and extranodal NK/T-cell lymphoma of the nasal cavity with nasopharynx extension (N-NP NKTCL). Methods: A total of 89 patients with NP NKTCL and 113 patients with N-NP NKTCL from January 2000 to June 2015 were retrospectively analyzed. Clinical and pathological features, treatment responses and prognosis were compared between the two groups. Results: NP NKTCL patients showed similar clinicopathological features with those with N-NP NKTCL, except that the former had a relative low proportion of elevated lactate dehydrogenase (LDH) levels (28.1% vs. 41.6%; P=0.001). Both of two groups presented with high proportion of cervical lymph node involvement (55.1% and 42.5%; P=0.076). The 5-year overall survival (OS) rates in these two groups were 63.2% and 54.6%, respectively, whereas 5-year progress-free survival (PFS) rates were 50.7% and 45.6%, respectively. For the patients with stage Ⅰ and Ⅱ, the 5-year OS and PFS rates in these two groups were 68.8% and 55.7% as well as 55.6% and 47.2%, respectively. These were no statistically significant differences between two groups (all P>0.05). The complete response (CR) rate after initial chemotherapy in NP NKTCL group was 43.8%, which was significant higher than that of 19.6% in N-NP NKTCL group (P=0.006). Additionally, the CR rate after primary radiotherapy was 63.4% and 62.7%, respectively (P=0.629). The NP NKTCL patients with stage Ⅰ and Ⅱ who accepted radiotherapy with or without chemotherapy had similar survival times with chemotherapy alone, showing the 5-year OS rates of 70.5% and 33.3% (P=0.238), as well as the 5-year PFS rates of 56.7% and 33.3%, respectively (P=0.431). Similar results were found in N-NP NKTCL group, the 5-year OS rates for patients with radiotherapy with or without chemotherapy and chemotherapy alone were 57.4% and 33.3% (P=0.246), while the 5-year PFS rates were 49.3% and 16.7% (P=0.177), respectively. Besides, the relapse pattern of NP NKTCL and N-NP NKTCL groups was also similar, mainly involving the distant extra-nodal organs followed by lymph nodes. Conclusion: The patients with N-NP NKTCL and NP NKTCL showed similar clinical and prognostic features, however, the initial response to chemotherapy was different.

Vitamin D deficiency is associated with inferior survival of patients with extranodal natural killer/T-cell lymphoma.

Vitamin D deficiency is a common health issue; however, the effect of vitamin D deficiency on the survival of T-cell lymphoma is still not clear. We evaluated the impact of serum vitamin D level of patients with peripheral T-cell lymphoma (PTCL) and extranodal natural killer/T-cell lymphoma (ENKTL) on survival outcome. Pretreatment levels of 25-hydroxyvitamin D [25(OH)D] and inflammatory cytokines were measured in serum samples that were archived at diagnosis, and we evaluated their association with survival in newly diagnosed patients with PTCL (n = 137) and ENKTL (n = 114) at a university-based hospital in Korea. An independent cohort from Rui Jin Hospital (Shanghai, China) was used for validation. The median 25(OH)D serum level was 12.0 ng/mL (1.3-60.0 ng/mL), and 40% had less than 10 ng/mL, which was defined as vitamin D deficiency. Median serum 25(OH)D levels were similar between PTCL (11.5 ng/mL) and ENKTL (12.9 ng/mL); however, vitamin D deficiency was associated with inferior survival in ENKTL but not with PTCL. The independent validation cohort (n = 115) also showed a significant association of vitamin D deficiency with poor survival in ENKTL. The 25(OH)D level had an inverse relation with inflammatory cytokines; this association had a negative effect only on survival of ENKTL, and not on PTCL. In conclusion, vitamin D deficiency was associated with inferior survival outcome of patients with ENKTL.

Aggressive natural killer (NK)-cell leukaemia and extranodal NK/T-cell lymphoma are two distinct diseases that differ in their clinical presentation and cytogenetic findings.

AIMS: Aggressive natural killer (NK)-cell leukaemia (ANKCL) and extranodal NK/T-cell lymphoma (ENKTCL) with secondary bone marrow involvement are rare bone marrow NK/T-cell neoplasms and share similar features. This study aimed to distinguish these two entities. METHODS AND RESULTS: We studied bone marrow NK/T-cell neoplasms by classifying them into those with no extramedullary mass (group 1, eight cases) and those with extramedullary mass (group 2, 13 cases). The two groups showed similar clinical presentations and pathological features. Fever and cytopenia were the most common clinical presentations in both groups. The neoplastic cells varied from small and relatively monotonous cells to large pleomorphic cells. In six cases (two in group 1, and four in group 2), the neoplastic infiltrate was inconspicuous, consisting of ≤10% of marrow cells in the interstitium, which were hardly identified by haematoxylin and eosin staining alone. Nearly all patients rapidly died, regardless of the neoplastic infiltrate volume. All of the group 1 patients fulfilled the World Health Organisation 2017 diagnostic criteria of ANKCL, and their survival was significantly worse than that of the group 2 patients (P = 0.035). In addition, there was a significant association between being in group 1 and chromosome 7 abnormalities. Chromosome 6q deletion, which is commonly reported in ENKTCL, was seen in two of our group 2 patients, and was not observed in any of our group 1 patients. CONCLUSION: ANKCL with no extramedullary mass should be distinguished from ENKTCL with bone marrow involvement, as the former shows distinct outcomes and genetic features.