Risk-adapted therapy for early-stage extranodal nasal-type NK/T-cell lymphoma: analysis from a multicenter study

Extranodal NK/T Cell Lymphoma, Nasal Type (ENKTL-NT): An Update on Epidemiology, Clinical Presentation, and Natural History in North American and European Cases

PURPOSE OF REVIEW

Extranodal NK/T cell lymphoma, nasal type (ENKTL-NT) is an aggressive extranodal non-Hodgkin lymphoma most commonly occurring in East Asia and Latin America but with increasing incidence in the United States. Data on epidemiology, disease presentation, and outcome for European and North American ("Western") cases are very limited. We review published landmark clinical studies on ENKTL-NT in the West and report in detail recent data, including our institutional experience.

RECENT FINDINGS

We highlight key observations in its epidemiology, natural history, and trends in clinical management. In the USA, ENKTL-NT is more common among Asian Pacific Islanders (API) and Hispanics compared to non-Hispanic whites. Published studies indicate less heterogeneity in clinical presentation in Western ENKTL-NT compared to Asian patients. While there is variation in age at diagnosis, presence of antecedent lymphoproliferative disorders, and outcomes among racial/ethnic groups, the universal association of ENKTL-NT with EBV and the poor response of this neoplasm to anthracycline-based therapy is consistent across all geographic areas. Data on epidemiology, disease presentation, and clinical outcomes in mature T cell and NK cell (T/NK cell) neoplasms, including ENKTL-NT, in Europe and North America are very limited. As the classification and diagnostic characterization of the currently recognized T/NK cell lymphoma disease entities continue to evolve, gaps and inconsistencies in data reporting across different studies are being recognized. Despite these limitations, several studies from the USA suggest that the incidence of ENKTL-NT is higher in Asian Pacific Islanders (API) and non-white Hispanics and that outcomes may be worse in non-whites. However, the universal association of ENKTL-NT with Epstein-Barr virus (EBV) across all ethnic groups suggests a common pathogenesis. Given the overlap between the entities included in the category of T/NK cell neoplasms, there is a need to further define biological and clinical differences that may affect diagnosis, treatment, and outcome.

Hemoglobin level, a prognostic factor for nasal extranodal natural killer/T-cell lymphoma patients from stage I to IV: A validated prognostic nomogram

Although nasal extranodal natural killer/T-cell lymphoma (nasal ENKL) shares some prognostic factors with other lymphomas, seldom studies had explored the prognostic value of hemoglobin. The ENKL cases in stage I–IV during 2000 to 2015 were collected from two medical centers (group A, n = 192), and were randomly divided into the group B (n = 155) and C (n = 37). Although the significant factors identified by the univariate analysis differed between the group A and B, the multivariate Cox regression indicated the same factors. C-index of the model was slightly better than Yang’s, but its integrated Brier score (IBS) was obviously lower than Yang’s both in the group A and B. Additionally, minimal depth of random survival forest (RSF) classifier confirmed that the prognostic ability of hemoglobin was better than age both in the group A and B. In the calibration of the nomogram, the predicted 3-year or 5-year OS of our nomogram well agreed with the corresponding actual OS. In conclusion, Hemoglobin is a prognostic factor for nasal ENKL patients in stage I - IV, and integrating it into a validated prognostic nomogram, whose generalization error is the smallest among the evaluated models, can be used to predict the patients’ outcome.

Intensity-modulated radiotherapy has superior outcomes to three-dimensional conformal radiotherapy in patients with stage IE-IIE extranodal nasal-type natural killer/T-cell lymphoma

We compared the treatment outcomes, toxicities and prognoses of patients with stage IE-IIE extranodal natural killer/T-cell lymphoma (ENKTL) treated with intensity-modulated radiotherapy (IMRT) or three-dimensional conformal radiotherapy (3DCRT). Newly diagnosed early-stage ENKTL patients (N = 173) were enrolled and received extended involved-field radiotherapy following induction chemotherapy. Patients were treated with 3DCRT (n = 98) or IMRT (n = 75). One-to-one matching of the IMRT and 3DCRT groups was performed through propensity score matching, which yielded 23 pairs of patients. The two groups achieved similar complete remission rates before and after radiotherapy (P > 0.05). All patients were followed up for a median of 41 months. The rates of local recurrence-free survival (LRFS, P < 0.001), progression-free survival (PFS, P = 0.003) and overall survival (OS, P = 0.003) were longer in the IMRT than 3DCRT group. In the matched patients, IMRT was still associated with superior LRFS (P = 0.024), but not with improved PFS (P = 0.113) or OS (P = 0.115). Multivariate analysis also suggested IMRT was a favorable independent factor for LRFS (HR = 2.230, P = 0.043), but not for PFS (P = 0.195) or OS (P = 0.116). Equivalent acute toxicities were observed for 3DCRT and IMRT; however, among stage II patients who had received cervical irradiation, the rate of late xerostomia was lower in the IMRT than 3DCRT group (38.5% vs. 66.7%, P = 0.046). Overall, IMRT yielded a better treatment response and local control than 3DCRT, and tended to reduce late xerostomia in patients with cervical irradiation, but failed to enhance OS. Thus, IMRT is recommended for the treatment of stage IE-IIE ENKTL patients.

Autologous hematopoietic stem cell transplantation may improve long-term outcomes in patients with newly diagnosed extranodal natural killer/T-cell lymphoma, nasal type: a retrospective controlled study in a single center

Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL) is a rare disease with a poor prognosis. The long-term effect of autologous hematopoietic stem cell transplantation (auto-HSCT) on ENKTL has been reported occasionally but needs further investigation. In this retrospective study from a single center, 20 ENKTL patients who received induction chemotherapy followed by auto-HSCT ± involved-field radiotherapy (IFRT) ± additional chemotherapy were enrolled as a study group. Another 60 fit ENKTL patients who received induction chemotherapy ± IFRT ± additional chemotherapy were selected as the control group. Baseline characteristics of all patients were well balanced. Our analysis showed that after a median follow-up time of 61.0 months (95% CI 52.3-69.7), the auto-HSCT treated group showed better overall survival (OS) than the control group (p = 0.045). The median OS of the auto-HSCT-treated group was not reached, but that of the control group was 62.0 months. Five-year comparison of OS between the two groups also showed a significant difference (79.3 vs. 52.3%, p = 0.026). We suggest that auto-HSCT treatment, in combination with chemoradiotherapy, may prolong OS and improve the long-term outcomes of fit patients with ENKTL compared to treatment with chemoradiotherapy alone.

Prognostic role of ABO blood type in patients with extranodal natural killer/T cell lymphoma, nasal type: a triple-center study

BACKGROUND

The prognostic significance of ABO blood type for lymphoma is largely unknown. We evaluated the prognostic role of ABO blood type in patients with extranodal natural killer (NK)/T-cell lymphoma (ENKTL).

METHODS

We retrospectively analyzed clinical data of 697 patients with newly diagnosed ENKTL from three cancer centers. The prognostic value of ABO blood type was evaluated using Kaplan-Meier curves and Cox proportional hazard models. The prognostic values of the International Prognostic Index (IPI) and the Korean Prognostic Index (KPI) were also evaluated.

RESULTS

Compared with patients with blood type O, those with blood type non-O tended to display elevated baseline serum C-reactive protein levels (P = 0.038), lower rate of complete remission (P = 0.005), shorter progression-free survival (PFS, P < 0.001), and shorter overall survival (OS, P = 0.001). Patients with blood type O/AB had longer PFS (P < 0.001) and OS (P = 0.001) compared with those with blood type A/B. Multivariate analysis demonstrated that age >60 years (P < 0.001), mass ≥5 cm (P = 0.001), stage III/IV (P < 0.001), elevated serum lactate dehydrogenase (LDH) levels (P = 0.001), and blood type non-O were independent adverse predictors of OS (P = 0.001). ABO blood type was found to be superior to both the IPI in discriminating patients with different outcomes in the IPI low-risk group and the KPI in distinguishing between the intermediate-to-low- and high-to-intermediate-risk groups.

CONCLUSIONS

ABO blood type was an independent predictor of clinical outcome for patients with ENKTL.

A neutralized human LMP1-IgG inhibits ENKTL growth by suppressing the JAK3/STAT3 signaling pathway

Latent membrane protein 1 (LMP1), which is associated with the development of different types of Epstein-Barr virus (EBV) related lymphoma, has been suggested to be an important oncoprotein. In this study, a human anti-LMP1 IgG antibody (LMP1-IgG) was constructed and characterized by ELISA, western blotting (WB), affinity and immunohistochemistry (IHC) analyses. CCK-8, MTT, apoptosis assays, antibody-dependent cell-mediated cytotoxicity (ADCC) and CDC (complement-dependent cytotoxicity) assays were performed to evaluate the inhibitory effects of LMP1-IgG on extranodal nasal-type natural killer (NK)/T-cell lymphoma (ENKTL). Then, the influence of LMP1-IgG on the JAK/STAT signaling pathway was investigated. The results showed that the successfully constructed LMP1-IgG inhibited proliferation, induced apoptosis, and activated ADCC and CDC of ENKTL in a concentration- and time- dependent manner. Moreover, phosphorylation of JAK3 and STAT3 was inhibited by LMP1-IgG. Our data indicate that LMP1-IgG may provide a novel and promising therapeutic strategy for the treatment of LMP1-positive ENKTL.

Current treatment approaches for NK/T-cell lymphoma

Extranodal NK/T-cell lymphoma, nasal type (ENKL), is a form of lymphoma characterized by preferential extranodal involvement, Epstein-Barr virus (EBV) association, and geographic diversity in incidence. ENKL tumor cells express P-glycoprotein, which is related to multidrug resistance (MDR). This MDR phenomenon is thought to be the major reason why ENKL is resistant to anthracycline-containing chemotherapies and has led researchers to explore novel therapeutic strategies. Since the early 2000s, next-generation therapies, including upfront radiotherapy, chemotherapy, or concurrent chemoradiotherapy using non-MDR-related drugs, have markedly changed the management of ENKL. However, a recent large retrospective study in Japan revealed several limitations of next-generation therapies, in particular that they resulted in almost no improvement of early disease progression. This review will summarize the current management of ENKL, primarily based on clinical trial results, and provide clues for better future management.

Novel approaches to targeting MYD88 in Waldenström macroglobulinemia

INTRODUCTION

Waldenström macroglobulinemia (WM) is an incurable lymphoma characterized by the accumulation of IgM-producing lymphoplasmacytic cells in the bone marrow and other organs. Although WM patients can experience prolonged remissions, the disease invariably recurs advocating for the need of novel treatments in order to achieve higher response and survival rates. The discovery of a recurrent mutation in the MYD88 gene and an increased understanding behind the biology of MYD88 signaling have provided the opportunity to developing novel agents targeting the MYD88 pathway. Areas covered: The present review focuses on potential therapies that could change the landscape of treatment of patients with WM, specifically focusing on inhibitors of the Bruton tyrosine kinase (BTK), phosphatidylinositol-3 kinase, hematopoietic cell kinase, interleukin-1 receptor associated kinase and MYD88 assembly. Expert commentary: Novel agents such as the BTK inhibitor ibrutinib has shown to be safe and highly effective in the treatment of WM. Ibrutinib has been approved in Europe and the United States for its use in patients with symptomatic WM. Prospective studies are ongoing and/or planned to study many other novel agents alone and in combination with aims at improving response, survival and quality of life in patients with WM.

The diagnosis and management of NK/T-cell lymphomas

Extranodal natural killer (NK)/T-cell lymphoma is an aggressive malignancy of putative NK-cell origin, with a minority deriving from the T-cell lineage. Pathologically, the malignancy occurs in two forms, extranodal NK/T-cell lymphoma, nasal type; and aggressive NK-cell leukaemia. Lymphoma occur most commonly (80%) in the nose and upper aerodigestive tract, less commonly (20%) in non-nasal areas (skin, gastrointestinal tract, testis, salivary gland), and rarely as disseminated disease with a leukemic phase. Genetic analysis showed mutations of genes involved in the JAK/STAT pathway, RNA assembly, epigenetic regulation, and tumor suppression. In initial clinical evaluation, positron emission tomography computed tomography, and quantification of plasma EBV DNA are mandatory as they are useful for response monitoring and prognostication. In stage I/II diseases, combined chemotherapy and radiotherapy (sequentially or concurrently) is the best approach. Conventional anthracycline-containing regimens are ineffective and should be replaced by non-anthracycline-containing regimens, preferably including L-asparaginase. Radiotherapy alone is associated with high systemic relapse rates and should be avoided. In stage III/IV diseases, non-anthracycline-regimens-containing L-asparaginase are the standard. In relapsed/refractory cases, blockade of the programmed death protein 1 has recently shown promising results with high response rates. In the era of effective non-anthracycline-containing regimens, autologous haematopoietic stem cell transplantation (HSCT) has not been shown to be beneficial. However, allogeneic HSCT may be considered for high-risk or advanced-stage patients in remission or relapsed/refractory patients responding to salvage therapy. Prognostic models taking into account presentation, interim, and end-of-treatment parameters are useful in triaging patients to different treatment strategies.

Clinical Features and Current Optimal Management of Natural Killer/T-Cell Lymphoma

Extranodal natural killer/T-cell lymphoma, nasal type (ENKL), is a rare subtype of non-Hodgkin lymphoma, and its treatment outcome was previously poor. Novel treatment strategies have improved the outcomes of ENKL remarkably in the last decade. Nowadays, patients with localized nasal ENKL are recommended treatment with concurrent chemoradiotherapy, and their 5-year overall survival rate is approximately 70%. In patients with advanced or relapsed/refractory disease, the efficacy of l-asparaginase-containing therapy has been confirmed. However, there still remain unmet needs in the treatment of ENKL. Continued efforts should be made to further improvements in the treatment of ENKL.

The Role of Radiation Therapy in the Management of Sinonasal and Ventral Skull Base Malignancies

Sinonasal and ventral skull base malignancies are rare tumors that arise in a complex anatomic location juxtaposed with critically important normal tissues. The standard treatment paradigm for most histologies has been surgery followed by postoperative radiation therapy. Because of their propensity to present at an advanced stage and the presence of nearby critical structures, patients are at risk for severe radiation-induced long-term toxicity. Recent advances in radiotherapy technique have improved the therapeutic ratio between tumor control and normal tissue toxicity. This article reviews issues pertinent to the use of radiotherapy in the management of these tumors.

Comparative Study of L-Asparaginase-Based LOP Regimen Over CHOP Regimen Before Radiotherapy for Stage IIE Extranodal Nasal Type NK/T Cell Lymphoma: A Study of 2 Centers

BACKGROUND

In this study we evaluated the efficacy of an L-asparaginase-based LOP (L-asparaginase, vincristine, and dexamethasone) regimen in extranodal Natural Killer (NK)/T-cell lymphoma (ENKTL) patients in the Guizhou province of China.

PATIENTS AND METHODS

Forty-eight patients were treated with the LOP (L-asparaginase, vincristine and dexamethasone) regimen chemotherapy (CT) and 32 patients with the CHOP (cyclophosphamide, tetrahydropyanyl adriamycin, vincristine, and prednisone) regimen. These patients then received involved-field radiotherapy (RT) with the doses of DT = 49-59 Gy.

RESULTS

A significant improvement of clinical end points with the LOP regimen was noticed compared with the CHOP regimen: 33 (68.8%) versus 16 (50.0%) for complete responses; 10 (20.8%) versus 5 (15.6%) for partial responses. There were statistical differences in objective response rates (43 [89.6%] for LOP vs. 21 [65.6%] for CHOP; P = .009), 3 years of overall survival (42 [87.5%] for LOP vs. 20 [62.5%] for CHOP; P = .006) and progression-free survival (32 [79.2%] for LOP vs. 16 [50.0%] for CHOP; P = .007).

CONCLUSION

The results showed that the LOP regimen is safe and much more efficient than the CHOP regimen for stage IIE ENKTL patients. They indicate that the LOP regimen is a satisfying alternative protocol among the other L-asparaginase-based regimens reported so far, such as SMILE (dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide), GELOX (gemcitabine, oxaliplatin, and L-asparaginase), CHOP-L, and sandwich (CT, then RT, then CT).

Treatments and Outcomes of Patients With Extranodal Natural Killer/T-Cell Lymphoma Diagnosed Between 2000 and 2013: A Cooperative Study in Japan

Purpose

To elucidate the management and outcomes of patients with extranodal natural killer/T-cell lymphoma, nasal type (ENKL), who were diagnosed between 2000 and 2013 in Japan.

Patients and Methods

Data from 358 patients with ENKL diagnosed between 2000 and 2013 from 31 institutes were retrospectively analyzed.

Results

Patients’ median age was 58 years, and 257 (72%) had localized disease. The most common first-line treatment was radiotherapy with dexamethasone, etoposide, ifosfamide, and carboplatin (RT-DeVIC) (66%) for localized ENKL and L-asparaginase–containing chemotherapy (30%) for advanced ENKL. With a median follow-up of 5.8 years, overall survival (OS) rates at 5 years for localized and advanced ENKL were 68% and 24%, respectively. The prognostic index of natural killer lymphoma was validated in our study, although only 4% of patients with localized ENKL were classified as high risk. With a median follow-up of 5.6 years, OS and progression-free survival at 5 years in the 150 patients who received RT-DeVIC in clinical practice were 72% (95% CI, 63% to 78%) and 61% (95% CI, 52% to 69%), respectively. Toxicities of RT-DeVIC were comparable to those in a previous trial. Multivariate analysis in patients with localized ENKL who received RT-DeVIC identified elevated soluble interleukin-2 receptor as an independent predictive factor for worse OS and progression-free survival (adjusted hazard ratios, 2.28 and 2.46; 95% CI, 1.24 to 4.23 and 1.42 to 4.28; P = .008 and .0014, respectively).

Conclusion

Favorable OS in response to new treatments was demonstrated in a large number of patients. Improved treatment approaches are needed for localized ENKL exhibiting elevated pretreatment soluble interleukin-2 receptor.

Treatment outcomes of and prognostic factors for definitive radiotherapy with and without chemotherapy for Stage I/II nasal extranodal NK/T-cell lymphoma

Treatment strategies for nasal extranodal NK/T-cell lymphoma (ENKTL), including sequential chemotherapy followed by radiotherapy (SCRT), concurrent chemoradiotherapy (CCRT), or radiotherapy alone (RT), remain varied. The purpose of this study was to assess the treatment outcome, the toxicity, and the potential prognostic factors for patients with early-stage nasal ENKTL treated using definitive RT (minimum of 50 Gy) with or without chemotherapy. From 1998 to 2014, 37 patients were included in the study. Eight patients were treated with RT alone, 1 with CCRT, and 28 with SCRT. Local regional control (LRC), progression-free survival (PFS), and overall survival (OS) were calculated using the Kaplan-Meier method. RT resulted in an overall response rate of 91.2%, with a complete response rate of 78.4%. After a median follow-up time of 36.8 months, the 3-year LRC, PFS and OS were 87.4%, 64.0% and 76.3%, respectively. Acute severe toxicity (Grade 3) of mucositis was observed in 6 (16.2%) of the 37 patients. In univariate analyses, extensive disease (Stage I/II with local invasiveness) and the presence of B symptoms were significantly associated with a poor PFS, whereas extensive disease was significantly associated with a poor OS. Multivariate analysis identified the presence of extensive disease as an independent predictor of PFS (P < 0.001) and OS (P = 0.015). High-dose RT with or without chemotherapy reported promising locoregional control and a favorable outcome for patients with early-stage nasal ENKTL without local invasiveness. Further investigation of new treatment strategies for patients with local invasiveness is warranted.

PD-L1 is upregulated by EBV-driven LMP1 through NF-κB pathway and correlates with poor prognosis in natural killer/T-cell lymphoma

BACKGROUND

Natural killer/T-cell lymphoma (NKTCL) is an Epstein-Barr virus (EBV)-associated, highly aggressive lymphoma. Treatment outcome remains sub-optimal, especially for advanced-stage or relapsed diseases. Programmed cell death receptor 1 (PD-1) and PD ligand 1 (PD-L1) have become promising therapeutic targets for various malignancies, but their role in the pathogenesis and their interactions with EBV in NKTCL remains to be investigated.

METHODS

Expression of PD-L1 was measured in NK-92 (EBV-negative) and SNK-6 (EBV-positive) cells by western blot, quantitative real-time PCR and enzyme-linked immunosorbent assay, and flow cytometry, respectively. Latent membrane protein 1 (LMP1)-harboring lentiviral vectors were transfected into NK-92 cells to examine the correlation between LMP1 and PD-L1 expression. Proteins in the downstream pathways of LMP1 signaling were measured in NK-92 cells transfected with LMP1-harboring or negative control vectors as well as in SNK-6 cells. PD-L1 expression on tumor specimens and serum concentration of soluble PD-L1 were collected in a retrospective cohort of patients with Ann Arbor stage I~II NKTCL, and their prognostic significance were analyzed.

RESULTS

Expression of PD-L1 was significantly higher in SNK-6 cells than in NK-92 cells, at both protein and mRNA levels. Expression of PD-L1 was remarkably upregulated in NK-92 cells transfected with LMP1-harboring lentiviral vectors compared with those transfected with negative control vectors. Proteins in the MAPK/NF-κB pathway were upregulated in LMP1-expressing NK-92 cells compared with the negative control. Selective inhibitors of those proteins induced significant downregulation of PD-L1 expression in LMP1-expressing NK-92 cells as well as in SNK-6 cells. Patients with a high concentration of serum soluble PD-L1 (≥3.4 ng/ml) or with a high percentage of PD-L1 expression in tumor specimens (≥38 %) exhibited significantly lower response rate to treatment and remarkably worse survival, compared with their counterparts. A high concentration of serum soluble PD-L1 and a high percentage of PD-L1 expression in tumor specimens were independent adverse prognostic factors among patients with stage I~II NKTCL.

CONCLUSIONS

PD-L1 expression positively correlated LMP1 expression in NKTCL, which was probably mediated by the MAPK/NF-κB pathway. PD-L1 expression in serum and tumor tissues has significant prognostic value for early-stage NKTCL.

Chemotherapy combined with high-dose extended-field radiotherapy for stage I extranodal nasal-type natural killer/T-cell lymphoma

Background and objective

The objective of the study was to evaluate the efficiency of chemotherapy (CT) combined with high-dose extended-field radiotherapy (RT) in stage I extranodal nasal-type natural killer/T-cell lymphoma (NKTCL).

Patients and methods

Between January 2001 and November 2010, 103 stage I extranodal nasal-type NKTCL patients were retrospectively analyzed. Of these patients, 75 patients were treated by RT plus CT and 28 patients were treated by RT alone. CT included cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), or CHOP-like regimen.

Results

The median follow-up time was 42.6 months (range, 7.4–126.7 months). For patients in the RT alone group, the 5-year estimated progression-free survival (PFS) and overall survival (OS) rates were 67.0% and 71.4%, respectively. For patients in the RT + CT group, the 5-year estimated PFS and OS rates were 69.0% and 63.7%, respectively. In multivariate analysis, CT was an independent factor for PFS.

Conclusion

The doxorubicin-based CT combined with high-dose extended-field RT yielded promising outcomes for stage I extranodal nasal-type NKTCL, and CT was an independent factor for PFS.

Patterns of Primary Tumor Invasion and Regional Lymph Node Spread Based on Magnetic Resonance Imaging in Early-Stage Nasal NK/T-cell Lymphoma: Implications for Clinical Target Volume Definition and Prognostic Significance

PURPOSE

This study aimed to determine the pathways of primary tumor invasion (PTI) and regional lymph node (LN) spread based on magnetic resonance imaging (MRI) in early-stage nasal NK/T-cell lymphoma (NKTCL), to improve clinical target volume (CTV) delineation and evaluate the prognostic value of locoregional extension patterns.

METHODS AND MATERIALS

A total of 105 patients with newly diagnosed early-stage nasal NKTCL who underwent pretreatment MRI were retrospectively reviewed. All patients received radiation therapy with or without chemotherapy.

RESULTS

The incidences of PTI and regional LN involvement were 64.7% and 25.7%, respectively. Based on the incidence of PTI, involved sites surrounding the nasal cavity were classified into 3 risk subgroups: high-risk (>20%), intermediate-risk (5%-20%), and low-risk (<5%). The most frequently involved site was the nasopharynx (35.2%), followed by the maxillary (21.9%) and ethmoid (21.9%) sinuses. Local disease and regional LN spread followed an orderly pattern without LN skipping. The retropharyngeal nodes (RPNs) were most frequently involved (19.0%), followed by level II (11.4%). The 5-year overall survival (OS), progression-free survival (PFS), and locoregional control (LRC) rates for all patients were 72.8%, 65.2%, and 90.0%, respectively. The presence of PTI and regional LN involvement based on MRI significantly and negatively affected PFS and OS.

CONCLUSIONS

Early-stage nasal NKTCL presents with a high incidence of PTI but a relatively low incidence of regional LN spread. Locoregional spread followed an orderly pattern, and PTI and regional LN spread are powerful prognostic factors for poorer survival outcomes. CTV reduction may be feasible for selected patients.

[Efficacy of GLIDE chemotherapy for patients with newly diagnosed advanced-stage or relapsed/refractory extranodal natural killer cell lymphoma]

目的

研究GLIDE（吉西他滨、门冬酰胺酶、异环磷酰胺、地塞米松、依托泊苷）方案治疗初发进展期及复发难治性结外鼻型NK/T细胞淋巴瘤（ENKL）患者的有效性及安全性。

方法

纳入2010年3月至2016年3月收治的初发进展期及复发难治性ENKL患者42例，给予GLIDE方案化疗，中位疗程数为3(2~6）个，评估化疗结束后缓解率及早期（2个疗程后）缓解率，采用Kaplan-Meier方法统计无进展生存（PFS）及总生存（OS），同时采用Cox回归方法进行多因素分析，寻找影响患者PFS及OS的独立预后因素。

结果

31例（73.8%）患者达到完全缓解（CR），其中22例（52.4%）为早期CR，31例CR患者中14例接受序贯自体造血干细胞移植（ASCT）。1年PFS与OS率分别为65.6％和82.7%，4年PFS与OS率分别为48.2％和63.1%，中位OS时间未达到，中位PFS时间为30.5个月。多因素分析提示美国东部肿瘤协作组体能状态评分（ECOG评分）0~1分以及CR后序贯ASCT为减少复发、延长患者生存的有利因素。

结论

GLIDE方案能够有效治疗初发进展期及复发难治性ENKL, ECOG评分0~1分及CR后序贯ASCT治疗是患者获得较长PFS和OS时间的独立预后因素。

[Role of radiotherapy in the treatment of NK/T-cell nasal type and primary cerebral lymphomas]

The head and neck are common sites for extranodal non-Hodgkin lymphomas. Radiotherapy plays an important role in the treatment of low-grade lymphomas, with curative or palliative intent. In the case of high-grade lymphomas, its combination with chemotherapy is debated. Its role is however undeniable in two specific entities: NK/T-cell lymphoma NK/T nasal type, and primary central nervous system lymphomas, which are the subject of this review.

Genetic risk of extranodal natural killer T-cell lymphoma: a genome-wide association study

BACKGROUND

Extranodal natural killer T-cell lymphoma (NKTCL), nasal type, is a rare and aggressive malignancy that occurs predominantly in Asian and Latin American populations. Although Epstein-Barr virus infection is a known risk factor, other risk factors and the pathogenesis of NKTCL are not well understood. We aimed to identify common genetic variants affecting individual risk of NKTCL.

METHODS

We did a genome-wide association study of 189 patients with extranodal NKTCL, nasal type (WHO classification criteria; cases) and 957 controls from Guangdong province, southern China. We validated our findings in four independent case-control series, including 75 cases from Guangdong province and 296 controls from Hong Kong, 65 cases and 983 controls from Guangdong province, 125 cases and 1110 controls from Beijing (northern China), and 60 cases and 2476 controls from Singapore. We used imputation and conditional logistic regression analyses to fine-map the associations. We also did a meta-analysis of the replication series and of the entire dataset.

FINDINGS

Associations exceeding the genome-wide significance threshold (p<5 × 10(-8)) were seen at 51 single-nucleotide polymorphisms (SNPs) mapping to the class II MHC region on chromosome 6, with rs9277378 (located in HLA-DPB1) having the strongest association with NKTCL susceptibility (p=4·21 × 10(-19), odds ratio [OR] 1·84 [95% CI 1·61-2·11] in meta-analysis of entire dataset). Imputation-based fine-mapping across the class II MHC region suggests that four aminoacid residues (Gly84-Gly85-Pro86-Met87) in near-complete linkage disequilibrium at the edge of the peptide-binding groove of HLA-DPB1 could account for most of the association between the rs9277378*A risk allele and NKTCL susceptibility (OR 2·38, p value for haplotype 2·32 × 10(-14)). This association is distinct from MHC associations with Epstein-Barr virus infection.

INTERPRETATION

To our knowledge, this is the first time that a genetic variant conferring an NKTCL risk is noted at genome-wide significance. This finding underlines the importance of HLA-DP antigen presentation in the pathogenesis of NKTCL.

FUNDING

Top-Notch Young Talents Program of China, Special Support Program of Guangdong, Specialized Research Fund for the Doctoral Program of Higher Education (20110171120099), Program for New Century Excellent Talents in University (NCET-11-0529), National Medical Research Council of Singapore (TCR12DEC005), Tanoto Foundation Professorship in Medical Oncology, New Century Foundation Limited, Ling Foundation, Singapore National Cancer Centre Research Fund, and the US National Institutes of Health (1R01AR062886, 5U01GM092691-04, and 1R01AR063759-01A1).

Diagnosis and management of extranodal NK/T cell lymphoma nasal type

INTRODUCTION

Extranodal NK/T-cell lymphoma nasal type is a distinct clinicopathologic entity. The most common initial site of presentation is the nasopharyngeal area, but non-nasals sites including the skin and the gastrointestinal tract may be affected.

AREAS COVERED

The diagnosis and management of NK/T-cell lymphoma is discussed, based on a literature search on PubMed. NK/T-cell lymphoma are typically positive for CD3 (cytoplasmic), CD56, cytotoxic markers (granzyme B, TIA1) and Epstein Barr virus (EBV). Plasma EBV DNA is an accurate surrogate biomarker for lymphoma load. For stage I/II nasal lymphoma, a combination of chemotherapy and radiotherapy yields the best results. Concomitant chemoradiotherapy and sequential chemotherapy and radiotherapy give similar response rates and survivals. For stage III/IV nasal lymphoma and non-nasal lymphomas, chemotherapy is the mainstay of treatment. Conventional anthracycline-based regimens are ineffective. Recommended chemotherapy protocols are based on the use of L-asparaginase combined with other effective drugs. Durable remission can be expected in at least 60% of patients irrespective of stage. Prognostically models based on clinicopathologic parameters and EBV DNA load are useful in stratification of patients for therapy. Expert commentary: Current treatment leads to long-term survival in a significant proportion of patients. For relapsed patients, novel strategies are needed.

Encouraging experience in the treatment of nasal type extra-nodal NK/T-cell lymphoma in a non-Asian population

Extra-nodal NK/T-cell lymphoma, nasal type (EN-NK/TCL-NT), is rare in the Western world. We launched the current single-institutional retrospective study with Institutional Review Board approval to better understand the disease. 43 EN-NK/TCL-NT patients treated from 1996 to 2014 were analyzed, including 10 (23%) Asians and 33 (76%) non-Asians. 19/26 (73%) early-stage patients received short-course chemotherapy followed by radiotherapy. 14/17 (82%) advanced-stage patients received primary chemotherapy. Complete response rate was significantly higher in the modified-SMILE group than the accelerated-CHOP group (80% vs. 30%, p = 0.015). The 2-year overall survival (OS) and progression-free survival (PFS) were 60% and 40%, respectively. Early-stage disease had significantly higher 2-year OS (87% vs. 21%) and PFS (56% vs.18%) than advanced-stage (p < 0.001). Ethnicity had no prognostic difference. EN-NK/TCL-NT in non-Asians shared similar disease characteristics and treatment outcomes with Asians. Most early-stage patients have achieved durable remissions. Management of advanced-stage disease remains challenging, with frequent progression and high mortality.

Chemoradiotherapy for localized extranodal natural killer/T-cell lymphoma, nasal type, using a shrinking-field radiation strategy: multi-institutional experience

PURPOSES

The prognosis of localized extranodal natural killer/T-cell lymphoma, nasal type (ENKTL), has improved with the development of chemoradiotherapy. However, conventional extended-field radiotherapy may cause optic disorders. Our group has employed smaller radiation fields in an attempt to avoid toxicity. The efficacy and toxicity of treatments were evaluated.

MATERIALS AND METHODS

Chemoradiotherapy was delivered with a shrinking-field radiotherapy strategy. The endpoints of this study were overall survival (OS), local control (LC), progression-free survival (PFS), and toxicity.

RESULTS

Fifteen patients with localized ENKTL were treated. After irradiation (median, 40 Gy) to the tumor plus a prophylactic volume, a reduced treatment volume to the tumor was boosted (median, 10 Gy). Twelve patients underwent chemoradiotherapy and 3 patients received radiotherapy alone. A complete response was achieved in 12 and a partial response in 3 patients. The 5-year OS, PFS, and LC rates were 80, 67, and 93 %, respectively. Distant recurrence occurred in 4 patients and locoregional and distant recurrence in 1 patient. Cataract (grade 3) and dry eye (grade 2) were observed as late adverse events in 1 patient each.

CONCLUSIONS

Sufficiently high OS and LC were achieved with acceptable toxicities. Appropriate target volumes may be smaller with newer chemotherapy regimens.

Current Management Concepts: Primary Central Nervous System Lymphoma, Natural Killer T-Cell Lymphoma Nasal Type, and Post-transplant Lymphoproliferative Disorder

Primary central nervous system lymphoma, natural killer T-cell lymphoma nasal type, and post-transplant lymphoproliferative disorder are uncommon and complex lymphoproliferative disorders. These disorders present with different risk factors, have complex tumor characteristics, and require unique therapeutic interventions. These diseases require a multidisciplinary complex team approach. This article will update current management approaches and concepts.