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

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

High Efficacy and Drug Synergy of HDAC6-Selective Inhibitor NN-429 in Natural Killer (NK)/T-Cell Lymphoma

NK/T-cell lymphoma (NKTCL) and γδ T-cell non-Hodgkin lymphomas (γδ T-NHL) are highly aggressive lymphomas that lack rationally designed therapies and rely on repurposed chemotherapeutics from other hematological cancers. Histone deacetylases (HDACs) have been targeted in a range of malignancies, including T-cell lymphomas. This study represents exploratory findings of HDAC6 inhibition in NKTCL and γδ T-NHL through a second-generation inhibitor NN-429. With nanomolar in vitro HDAC6 potency and high in vitro and in cellulo selectivity for HDAC6, NN-429 also exhibited long residence time and improved pharmacokinetic properties in contrast to older generation inhibitors. Following unique selective cytotoxicity towards γδ T-NHL and NKTCL, NN-429 demonstrated a synergistic relationship with the clinical agent etoposide and potential synergies with doxorubicin, cytarabine, and SNS-032 in these disease models, opening an avenue for combination treatment strategies.

A new conditioning regimen with chidamide, cladribine, gemcitabine and busulfan significantly improve the outcome of high-risk or relapsed/refractory non-Hodgkin's lymphomas

Previous studies highlight the need for a more active conditioning therapy in high-risk or refractory and relapsed lymphomas. Our preclinical research shows that histone deacetylase inhibitors, such as either vorinostat or chidamide, sensitize lymphoma cells to the cytotoxic combination of cladribine, gemcitabine and busulfan, leading to cell apoptosis. To evaluate the efficacy of this chidamide-cladribine-gemcitabine-busulfan (ChiCGB) combination as a new conditioning therapy, we conducted a Phase II trial, as described here. Patients with high-risk, relapsed/refractory lymphomas received ChiCGB as conditioning therapy, after transplantation with autologous peripheral stem cells. The sample comprised 105 patients in total: 60 with B-cell non-Hodgkin lymphomas (B-NHL) and 45 with T-cell or natural killer/T-cell lymphoma (NK/T). All patients eventually achieved full hematopoietic recovery. Neutrophils and platelets were engrafted at a median of 10 days (8-14) and 13 days (8-38), respectively. There was no transplant-related mortality within 100 days of transplant. Neutropenic fever, mucositis and atopic dermatitis were the observed nonhematologic toxicities. At a median follow-up of 35.4 months, 80.6% of the patients presented with no tumor progression, and the overall survival (OS) reached as high as 86.1%. Concerning the OS rate, 94.5% of patients with B-NHL and 75.4% of patients with T-cell or NK/T lymphomas survived. These findings demonstrate the safety and validity of the proposed combined therapy for high-risk and refractory/relapsed lymphomas. Our study was registered on the Clinical Trial Registry (clinicaltrials.gov, NCT03151876).

Expression of PD-L1 on Monocytes Is a Novel Predictor of Prognosis in Natural Killer/T-Cell Lymphoma

Background: Natural killer/T-cell lymphoma (NKTCL) is a highly aggressive lymphoma with a dismal prognosis, and novel therapeutic targets are urgently needed. Programmed death-ligand 1 (PD-L1) has become a promising therapeutic target for various cancers, but most of the studies have focused on expression of PD-L1 on tumor cells. Expression of PD-L1 on tumor-infiltrating non-malignant cells, especially monocytes, has not been studied in NKTCL, and its prognostic value remains unknown. Materials and Methods: Expression of PD-L1 on tumor-infiltrating stromal cells was measured in NKTert and HS5 cells when cultured alone or co-cultured with NKTCL cell lines. Clinical samples were collected from 42 patients with newly diagnosed NKTCL. Expression of PD-L1 on monocytes was analyzed in patients' peripheral blood and tumor tissues using flow cytometry and immunofluorescent staining, respectively. Survival data were retrospectively collected and the prognostic significance of PD-L1 expression on monocytes was analyzed. Results: PD-L1 expression on tumor-infiltrating stromal cells was remarkably elevated when co-cultured with NKTCL cells. The percentage of PD-L1+ monocytes among all monocytes in peripheral blood was significantly higher in NKTCL patients than that in healthy individuals. Among NKTCL patients, percentage of PD-L1+ monocytes in blood positively correlated with that in tumor tissues. Patients with a higher percentage (≥78.2%) of PD-L1+ monocytes in blood or with a higher percentage (≥24.2%) of PD-L1+ monocytes in tumor tissues exhibited a significantly inferior survival, compared with their counterparts. A higher percentage of PD-L1+ monocytes in blood or tumor tissues was an independent adverse prognostic factor. Conclusions: Expression of PD-L1 on monocytes is up-regulated and has significant prognostic value in patients with NKTCL.

IL-2Rα up-regulation is mediated by latent membrane protein 1 and promotes lymphomagenesis and chemotherapy resistance in natural killer/T-cell lymphoma

BACKGROUND

Natural killer/T-cell lymphoma (NKTCL) is a highly aggressive non-Hodgkin lymphoma often resistant to chemotherapy. Serum level of soluble IL-2 receptor α (IL-2Rα) is elevated in NKTCL patients and correlates significantly with treatment response and survival. In the current study we examined the potential role of IL-2Rα by over-expressing IL-2Rα in representative cell lines.

METHODS

Levels of IL-2Rα were evaluated in the human natural killer cell line NK-92 and the NKTCL cell line SNK-6. Lentiviral vectors were used to express latent membrane protein 1 (LMP1) in NK-92 cells, and IL-2Rα in both NK-92 and SNK-6 cells. The biological effects of these genes on proliferation, apoptosis, cell cycle distribution, and chemosensitivity were analyzed.

RESULTS

Expression of IL-2Rα was significantly higher in SNK-6 cells than in NK-92 cells. Expressing LMP1 in NK-92 cells remarkably up-regulated IL-2Rα levels, whereas selective inhibitorss of the proteins in the MAPK/NF-κB pathway significantly down-regulated IL-2Rα. IL-2Rα overexpression in SNK-6 cells promoted cell proliferation by altering cell cycle distribution, and induced resistance to gemcitabine, doxorubicin, and asparaginase. These effects were reversed by an anti-IL-2Rα antibody.

CONCLUSIONS

Our results suggest that LMP1 activates the MAPK/NF-κB pathway in NKTCL cells, up-regulating IL-2Rα expression. IL-2Rα overexpression promotes growth and chemoresistance in NKTCL, making this interleukin receptor a potential therapeutic target.

Advances in the treatment of extranodal NK/T-cell lymphoma, nasal type

Extranodal natural killer/T-cell lymphoma, nasal type (ENKL) is a subtype of mature T- and natural killer cell lymphomas characterized by its association with Epstein-Barr virus and extranodal involvement. Although there is geographic variance in the frequency of ENKL, its clinical features are similar between Western countries and endemic areas, such as East Asia. Anthracycline-containing chemotherapy is not recommended to treat ENKL. No standard treatment has been established based on the results of randomized controlled trials. In patients with localized disease, radiotherapy is a core component of the recommended first-line therapy. Radiotherapy administered at 50 to 54 Gy, extended involved-site radiotherapy considering tumor invasiveness, and the use of intensity modulated radiation therapy or volumetric modulated arc therapy are associated with efficacy of radiotherapy. Although the use of concurrent chemoradiotherapy has been supported by the results of clinical trials, accumulating evidence supports the use of sequential chemoradiotherapy with non-anthracycline-containing regimens that include l-asparaginase and/or platinum anticancer agents. l-asparaginase-containing chemotherapy is a key component of first-line treatments for systemic ENKL. Hematopoietic stem cell transplantation is recommended as a front-line consolidation therapy for newly diagnosed advanced-stage ENKL. Newer agents including immune checkpoint inhibitors are being investigated for treating ENKL. In this modern ENKL treatment era, multidisciplinary efforts are needed to identify the best timing and sequencing of radiotherapy, l-asparaginase, platinum, newer agents, and hematopoietic stem cell transplantation.

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.

A phase 2 study of methotrexate, etoposide, dexamethasone, and pegaspargase chemotherapy for newly diagnosed, relapsed, or refractory extranodal natural killer/T-cell lymphoma, nasal type: a multicenter trial in Northwest China

The nasal type of extranodal natural killer/T‐cell lymphoma is a rare aggressive lymphoma with poor prognosis. To discover a successful treatment, we investigated the efficacy and safety of chemotherapy with methotrexate, etoposide, dexamethasone, and polyethylene glycol‐asparaginase (MESA). Three cycles of MESA were administered to 46 patients with new or relapsed/refractory natural killer/T‐cell lymphoma. Complete response after 3 treatment cycles was 43.5%, the overall response rate was 87%, and 2‐year overall survival was 83.4%. Complete response was significantly better for newly diagnosed patients than for patients with relapsed/refractory disease. Patients with newly diagnosed disease had a significantly better overall response rate after 1, but not after 2 or 3 treatment cycles. Overall survival and progression‐free survival did not differ over 2 years. Grade 1/2 toxicities were frequent, but MESA was associated with fewer grade 3/4 events or treatment‐related deaths. These results will require confirmation in larger prospective trials.

Consolidative treatment after salvage chemotherapy improves prognosis in patients with relapsed extranodal natural killer/T-cell lymphoma

The optimal treatment strategy for relapsed natural killer/T-cell lymphoma (NKTCL) remains largely unknown. We retrospectively reviewed the treatment modalities and prognosis of 56 relapsed NKTCL patients. Chemotherapy was the initial salvage treatment, followed by radiotherapy (RT) or autologous hematopoietic stem cell transplantation (AHSCT) as consolidative therapy, depending on the status of remission and the pattern of relapse. For patients with locoregional relapse alone, consolidative RT after salvage chemotherapy significantly improved prognosis compared with follow-up (5-year OS: 83.3 vs. 41.7%, P = 0.047). For patients with distant relapse, consolidative AHSCT after salvage chemotherapy significantly prolonged survival compared with follow-up (2-year OS: 100.0 vs. 20.0%, P = 0.004). Patients without consolidative treatment after response to salvage chemotherapy exhibited a comparable survival to those who experienced stable or progressive disease after chemotherapy. Asparaginase (ASP)-containing salvage chemotherapy failed to confer a survival advantage over ASP-absent chemotherapy (5-year OS: 44.2 vs. 39.3%, P = 0.369). In conclusion, consolidative RT or AHSCT improved prognosis in patients with relapsed NKTCL who responded to initial salvage chemotherapy, and the role of ASP in salvage chemotherapy requires further exploration in prospective studies.

High Pretreatment D-Dimer Levels Correlate with Adverse Clinical Features and Predict Poor Survival in Patients with Natural Killer/T-Cell Lymphoma

Pretreatment plasma D-dimer levels have been reported to predict survival in several types of malignancies. The aim of this study was to evaluate the prognostic value of D-dimer levels in patients with newly diagnosed natural killer/T-cell lymphoma (NKTCL). The cut-off value of D-dimer to predict survival was set as 1.2 μg/mL based on the receiver operating curve analysis. Patients with a D-dimer level ≥ 1.2 μg/mL had significantly more adverse clinical features, including poor performance status, advanced stage diseases, B symptoms, elevated serum lactic dehydrogenase levels, involvement of regional lymph nodes, more extranodal diseases, and higher International Prognostic Index and natural killer/T-cell lymphoma prognostic index scores. A D-dimer level ≥ 1.2 μg/mL was significantly associated with inferior 3-year overall survival (OS, 13.0 vs. 68.5%, P < 0.001). In the multivariate analysis, a D-dimer level ≥ 1.2 μg/mL remained an independent predictor for worse OS (HR: 3.13, 95% CI: 1.47-6.68, P = 0.003) after adjusting for other confounding prognostic factors. Among patients with Ann Arbor stage I-II diseases, those with a D-dimer level ≥ 1.2 μg/mL had a significantly worse survival than those with a D-dimer level < 1.2 μg/mL (3 year-OS: 76.2 vs. 22.2%, P < 0.001). Survival of early-stage patients with a high D-dimer level was similar to that of the advanced-stage patients. In conclusion, pretreatment plasma D-dimer level may serve as a simple but effective predictor of prognosis in patients with NKTCL.

The pretreatment albumin to globulin ratio predicts survival in patients with natural killer/T-cell lymphoma

Background. The pretreatment albumin to globulin ratio (AGR) has been reported to be a predictor of survival in several types of cancer. The aim of this study was to evaluate the prognostic impact of AGR in patients with natural killer/T-cell lymphoma (NKTCL). Methods. We retrospectively reviewed the available serum biochemistry results for 331 NKTCL patients before treatment. AGR was calculated as albumin/(total protein-albumin), and a cut-off value of 1.3 was used to define AGR as low or high. Survival analysis was used to assess the prognostic value of AGR. Results. A low AGR (<1.3) was associated with significantly more adverse clinical features, including old age, poor performance status, advanced stage, elevated lactate dehydrogenase, B symptoms, and high International Prognostic Index (IPI) and natural killer/T-cell lymphoma prognostic index (NKPI) scores. Patients with a low AGR had a significantly lower 5-year overall survival (44.5 vs. 65.2%, P < 0.001) and progression-free survival (33.1 vs. 57.4%, P < 0.001). In the multivariate analysis, a low AGR remained an independent predictor of poorer survival. Additionally, AGR distinguished patients with different outcomes in the IPI low-risk group and in the NKPI high-risk group. Discussion. Pretreatment AGR may serve as a simple and effective predictor of prognosis in patients with NKTCL.

GDP (Gemcitabine, Dexamethasone, and Cisplatin) Is Highly Effective and Well-Tolerated for Newly Diagnosed Stage IV and Relapsed/Refractory Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type

This study was conducted to evaluate the effectiveness and tolerance of GDP (gemcitabine, dexamethasone, and cisplatin) regimen in patients with newly diagnosed stage IV and relapsed/refractory extranodal natural killer/T-cell lymphoma, nasal type (ENKTL).The study enrolled 41 ENKTL patients who received GDP regimen at the Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between January 2008 and January 2015.The disease status was newly diagnosed stage IV in 15 patients and relapsed/refractory in 26 patients. The median number of cycles of chemotherapy per patient was 6 (range, 2-8 cycles). The overall response rate and complete-remission rate were 83.0% (34/41) and 41.5% (17/41), respectively. After a median follow-up of 16.2 months, 1-year progression-free survival rate and 1-year overall survival rate for the whole cohort were 54.5% and 72.7%. Grade 3 to 4 adverse events included neutropenia (34.1%), thrombocytopenia (19.5%), and anemia (14.6%).Our study has suggested high efficacy and low toxicity profile of GDP regimen in patients with newly diagnosed stage IV and relapsed/refractory ENKTL.

Radiotherapy and PGEMOX/GELOX regimen improved prognosis in elderly patients with early-stage extranodal NK/T-cell lymphoma

The optimal treatment strategy for elderly patients with natural killer/T-cell lymphoma (NKTCL) remains to be established. A total of 63 elderly patients with newly diagnosed NKTCL were retrospectively reviewed. Among the patients with stage I-II disease, 58.3 % received radiotherapy (RT) ± chemotherapy, and 41.7 % received chemotherapy alone. Compared with chemotherapy alone, RT ± chemotherapy elicited a significantly higher overall response rate (ORR) (100 vs. 57.1 %, P < 0.001) and substantially prolonged 5-year overall survival (OS) (55.3 vs. 18.0 %, P < 0.001) in patients with stage I-II disease. Compared with other chemotherapeutic regimens, pegaspargase plus gemcitabine and oxaliplatin (PGEMOX)/L-asparaginase plus gemcitabine and oxaliplatin (GELOX) was associated with a significantly higher ORR (92.9 vs. 51.6 %, P = 0.009) and a significantly improved 5-year OS (78.6 vs. 23.9 %, P = 0.010) in patients with stage I-II disease. Nine patients with stage I-II disease who were treated with PGEMOX/GELOX followed by RT had an encouraging outcome (5-year OS 100 %, 5-year progression-free survival (PFS) 85.7 %), which was superior to that of patients receiving other regimens followed by RT. In conclusion, RT played an important role for elderly patients with early-stage NKTCL, and the PGEMOX/GELOX regimen was superior to other regimens. The combination of them may be a promising treatment option.

Trial of LVDP regimen (L-asparaginase, etoposide, dexamethasone, and cisplatin, followed by radiotherapy) as first-line treatment for newly diagnosed, stage III/IV extranodal natural killer/T cell lymphoma

Stage III/IV extranodal natural killer/T cell lymphoma (ENKL) has a poor response and poor survival. Given the sensitivity of ENKL to radiotherapy and the fact that there is no consensus on standard chemotherapy, we conducted a clinical trial of LVDP regimen, combining LVDP chemotherapy (containing etoposide, dexamethasone, L-asparaginase, and cisplatin), followed by radiotherapy as a consolidation therapy regimen, for newly diagnosed patients with stage III/IV ENKL to evaluate the efficacy and safety of this regimen. The primary endpoints were overall response rate (ORR) and survival [overall survival (OS) and progression-free survival (PFS)] at 1 or 2 years, while the secondary endpoints were toxicity and adverse effects. In total, 18 patients were enrolled in this trial from July 2010 to September 2013. The mean completed cycles of chemotherapy was 4.04 (range 1-8 cycles), and the ORR was 50 %. During a mean follow-up of 21.8 months (range 2-51 months), the 1-year OS and PFS rates were 72.2 and 50.0 %, respectively, the 2-year OS and PFS rates were 33.3 and 22.2 %, respectively, and the median OS and PFS were 23.0 and 10.5 months, respectively. Severe adverse effects during therapy included six cases of grade 3/4 bone marrow suppression and one case of grade 3 transaminase increase. Sex, eastern cancer oncology group, performance status, Korean Prognostic Index, International Prognostic index, and bone marrow infiltration may influence the prognosis of advanced-stage ENKL.

Association between higher expression of YB-1 and poor prognosis in early-stage extranodal nasal-type natural killer/T-cell lymphoma

Aim: A recent study shows that YB-1-related biomarkers affect the prognosis of patients with natural killer/T-cell lymphoma (NKTCL). The aim of this study was to determine whether there is an association between YB-1 expression and the prognosis of patients with early-stage extranodal nasal-type NKTCL. Materials & methods: To clarify the roles of YB-1 in early-stage extranodal nasal-type NKTCL, we used immunohistochemical studies to examine YB-1 expression in 36 early-stage extranodal nasal-type NKTCL specimens. Results: Subsequently, YB-1 expression was correlated with clinicopathologic parameters. Higher expression of YB-1 was associated with an increased potential for relapse, poor disease-free survival and reduced overall survival. Discussion: Higher expression of YB-1 could be an independent risk factor for poor prognosis in patients with early-stage extranodal nasal-type NKTCL. Understanding the biology of YB-1-mediated pathways may lead to novel therapeutic strategies for early-stage extranodal nasal-type NKTCL.

Extranodal natural killer/T-cell lymphoma: advances in the management

PURPOSE OF REVIEW

Extranodal natural killer (NK)/T-cell lymphoma, nasal-type is a highly aggressive disease more frequent in Asia than in Western countries. There is no consensus treatment. The outcome depends on disease stage. Localized NK/T-cell lymphomas often respond to radiotherapy. In contrast, patients who have extensive disease or who relapse after radiotherapy have a very poor prognosis. Overall, long-term survival in these lymphomas tends to be inferior to that for other aggressive lymphomas. This review focuses on the new management modalities in light of advances in risk stratification, patient monitoring and treatment strategies.

RECENT FINDINGS

Many parameters have been reported to correlate with prognosis and new staging systems have been elaborated. Detecting Epstein-Barr virus (EBV) in the bone marrow is important for staging and measuring EBV DNA in the serum improved monitoring response to therapy. Radiation modalities have been precised and new strategies combining radiation and chemotherapy have been proposed for patients with localized disease. The particular efficacy of L-asparaginase in this disease has been confirmed and L-asparaginase-based regimens have been studied in prospective trials for patients with refractory, relapsing or disseminated disease with good results. Laboratory studies may point the way toward new therapeutic approaches.

SUMMARY

Early-stage disease is treated by involved-field radiotherapy with adjuvant chemotherapy. L-Asparaginase-containing regimens are the mainstay of treatment for advanced or disseminated disease. The role of targeted therapies, autologous and allogeneic haematopoietic stem cell transplantation is yet to be clearly defined.

Primary NK/T cell lymphoma nasal type of the colon

Since nasal NK/T-cell lymphoma and NK/T-cell lymphoma nasal type are rare diseases, colonic involvement has seldom been seen. We report a case of a patient with a primary NK/T-cell lymphoma nasal type of the colon. The patient had no history of malignant diseases and was diagnosed after exhaustive study in the context of fever of unknown origin. The first therapeutic approach followed the DA-EPOCH-protocol: etoposide, prednisone, doxor-rubicin, vincristine and cyclophosphamide. The persistence of constitutional symptoms after the first treatment course motivated the switch to a second line following the SMILE-protocol: dexamethasone, metotrexate, ifosfamide, E.coli L-asparaginase, and etoposide. Despite intensive chemotherapy, the patient died 2 months after the diagnose of an extranodal NK/T-cell lymphoma of the colon and 4 months after the first symptomatic appearance of disease.

Gemcitabine-based combination regimen in patients with peripheral T-cell lymphoma

This study was conducted to evaluate the efficacy and safety of gemcitabine-based combination regimen in patients with peripheral T-cell lymphoma (PTCL). Between May 2007 and August 2011, 26 consecutive patients with PTCL were enrolled in this study. Of these 26 patients, histology was extranodal NK/T-cell lymphoma, nasal type in 14 (53.9 %), peripheral T-cell lymphoma, not otherwise specified in nine (34.6 %), anaplastic large cell lymphoma, ALK negative in three (11.5 %). The majority of patients had newly diagnosed (65.4 %) and advanced (80.8 %) diseases. Treatment regimen was DIMG (dexamethasone, ifosfamide, methotrexate, and gemcitabine) given to the first 6 patients, and GDP (gemcitabine, dexamethasone, and cisplatin) given to the remaining 20 patients. The median follow-up time was 25 (range 7-60) months. The overall response rate was 88.5 %. Twelve (46.2 %) patients achieved complete remission, 11 (42.3 %) patients achieved partial remission, and 1 (3.8 %) patient had stable disease (SD), two (7.7 %) patients had progressive diseases. The 1- and 2-year progression-free survival rates were 58.7 and 45.9 %, while 1- and 2-year overall survival rates for all patients were 80.6 and 63.7 %, respectively. Adverse events included grade 3 or 4 neutropenia (35.0 %) and thrombocytopenia (15.0 %) from patients treated with GDP. Grade 3 or 4 neutropenia and thrombocytopenia were 100.0 and 66.7 %, respectively, for patients who received DIMG regimen. Our study has demonstrated that the gemcitabine-based combination regimen, especially GDP regimen, is safe and well tolerated with promising clinical activity in patients with PTCLs.

Survival benefit with salvage radiotherapy for patients with locoregionally recurrent extranodal NK/T cell lymphoma, nasal type

The purposes of this study are to evaluate prognosis in patients with locoregionally recurrent extranodal nasal-type NK/T cell lymphoma (NKTCL) and to determine the value of salvage radiotherapy. Forty-two patients with NKTCL who developed first locoregional recurrence with (n = 13) or without (n = 29) systemic failure were reviewed. Retreatment included chemotherapy (n = 20), radiotherapy (n = 13), and radiotherapy plus chemotherapy (n = 9). Fifteen patients were reirradiated for localized recurrent disease. The 5-year overall survival (OS) rate after recurrence was 40 %, with a median survival of 26 months. The 2-year OS rate and median OS were 68 % and 36 months for locoregional recurrence only, compared with 31 % and 14 months for both locoregional and systemic recurrence, respectively (p = 0.034). Subgroup analysis for patients with localized recurrent disease revealed an improved OS with radiotherapy. The 2-year and 5-year OS rates were 77 and 69 % for radiotherapy, respectively, compared with a 2-year OS rate of 50 % and median OS of 16 months for chemotherapy alone (p = 0.006). Patients with localized recurrence had a better prognosis than those with systemic recurrence. Salvage radiotherapy or reirradiation resulted in a favorable prognosis for patients with localized recurrent disease.

Allogeneic hematopoietic stem cell transplantation for advanced extranodal natural killer/T-cell lymphoma, nasal type

The prognosis for patients with advanced or refractory extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKL) is extremely poor. Thus, allogeneic stem cell transplantation (allo-HSCT) should be considered for this disease. However, reports of allo-HSCT for ENKL are limited because of the rarity of the disease. Here, we describe the clinical course of 12 cases of advanced and refractory ENKL treated with allo-HSCT, including five cases with cord blood transplant. With a median follow-up of 13 months (range, 1-168 months), seven patients are alive in remission, five have died, and one treatment-related death occurred. All patients with disease progression at transplant died of disease progression, whereas seven of eight patients with a complete or partial response are long-term survivors. Allo-HSCT is a feasible and promising consolidation therapy for advanced and relapsed ENKL. The disease status before allo-HSCT is well associated with general outcome, and thus induction treatment is very important for this disease.

Diagnosis and management of natural killer-cell malignancies

Natural killer (NK)-cell malignancies are uncommon neoplasms, which have been referred to as polymorphic reticulosis or angiocentric T-cell lymphomas in the past. In the current WHO classification, they are categorized as extranodal NK/T-cell lymphoma, nasal type and aggressive NK-cell leukemia. NK-cell malignancies show a geographical predilection for Asian and South American populations and are rare in the west. Pathologically, NK-cell lymphomas show a polymorphic neoplastic infiltrate with angioinvasion and angiodestruction. The lymphoma cells are CD2(+), cytoplasmic CD3ε(+) and CD56(+), with germline T-cell receptor gene. There is an almost invariable clonal episomal infection with Epstein-Barr virus. Clinically, NK-cell lymphomas can be classified into nasal, non-nasal and aggressive lymphoma/leukemia subtypes. Most nasal NK-cell lymphomas present with stage I/II disease. The early use of radiotherapy, either alone or concomitantly/sequentially with chemotherapy, is the most important factor in achieving successful treatment. Many stage I/II patients receiving radiotherapy alone fail systemically, so the use of chemotherapy is also considered necessary. Chemotherapy is indicated for stage III/IV nasal NK-cell lymphoma, and the non-nasal and aggressive subtypes. Recent regimens that incorporate the use of L-asparaginase have resulted in substantial improvements in outcome in high-risk, refractory or relapsed patients. High-dose chemotherapy and hematopoietic stem-cell transplantation with autologous or allogeneic hematopoietic stem cells may be beneficial to selected patients. Prognostication of patients with clinical prognostic models and presentation circulating Epstein-Barr DNA load may be useful in the stratification of patients for various treatment modalities.

Efficacy of L-asparaginase with methotrexate and dexamethasone (AspaMetDex regimen) in patients with refractory or relapsing extranodal NK/T-cell lymphoma, a phase 2 study

Extranodal NK/T-cell lymphoma, nasal type, is a rare and highly aggressive disease with a grim prognosis. No therapeutic strategy is currently identified in relapsing patients. We report the results of a French prospective phase II trial of an L-asparaginase-containing regimen in 19 patients with relapsed or refractory disease treated in 13 centers. Eleven patients were in relapse and 8 patients were refractory to their first line of treatment. L-Asparaginase–based treatment yielded objective responses in 14 of the 18 evaluable patients after 3 cycles. Eleven patients entered complete remission (61%), and only 4 of them relapsed. The median overall survival time was 1 year, with a median response duration of 12 months. The main adverse events were hepatitis, cytopenia, and allergy. The absence of antiasparaginase antibodies and the disappearance of Epstein-Barr virus serum DNA were significantly associated with a better outcome. These data confirm the excellent activity of L-asparaginase–containing regimens in extranodal NK/T-cell lymphoma. L-Asparaginase–based treatment should thus be considered for salvage therapy, especially in patients with disseminated disease. First-line L-asparaginase combination therapy for extranodal NK/T-cell lymphoma warrants evaluation in prospective trials. This trial is registered at www.clinicaltrials.gov as #NCT00283985.

Extranodal NK / T-cell lymphoma, nasal type: new staging system and treatment strategies

Extranodal NK/T-cell lymphoma (NTCL) is characterized by clinical heterogeneity based on clinical prognostic factors and survival outcome. NTCL subsets are classified as upper aerodigestive tract (UAT) NTCL or non-UAT NTCL; non-UAT has pathologic similarity to UAT-NTCL but is a clinically distinct subtype. Due to the clinical heterogeneity of NTCL, optimal treatment modalities and prognostic factors have been difficult to determine. Ann Arbor staging for lymphomas and the International Prognostic Index (IPI) have been used to predict prognosis for UAT-NTCL; however, local tumor invasiveness (bony invasion or perforation or invasion of the overlying skin) is the most significant factor for poor outcomes in localized UAT-NTCL. Thus, a new staging system is proposed: limited disease (stage I/II UAT-NTCL without local tumor invasiveness) and extensive disease (stage I/II with local invasiveness or stage III/IV disease of UAT NTCL, and non-UAT NTCL) based on treatment outcomes. NTCL is resistant to anthracycline-based chemotherapy, whereas non-anthracycline combination chemotherapy (such as ifosfamide, methotrexate, etoposide, and prednisolone) has an activity against NTCL as either a front-line or as a second-line treatment. The effectiveness of radiotherapy is evident in limited disease, but questionable in extensive disease.

Phase I/II Study of Concurrent Chemoradiotherapy for Localized Nasal Natural Killer/T-Cell Lymphoma: Japan Clinical Oncology Group Study JCOG0211

Purpose

To explore a more effective treatment for localized nasal natural killer (NK)/T-cell lymphoma, we conducted a phase I/II study of concurrent chemoradiotherapy.

Patients and Methods

Treatments comprised concurrent radiotherapy (50 Gy) and 3 courses of dexamethasone, etoposide, ifosfamide, and carboplatin (DeVIC). Patients with a newly diagnosed stage IE or contiguous IIE disease with cervical node involvement and a performance status (PS) of 0 to 2 were eligible for enrollment. The primary end point of the phase II portion was a 2-year overall survival in patients treated with the recommended dose.

Results

Of the 33 patients enrolled, 10 patients were enrolled in the phase I portion and a two thirds dose of DeVIC was established as the recommended dose. Twenty-seven patients (range, 21 to 68; median, 56 years) treated with the recommended dose showed the following clinical features: male:female, 17:10; stage IE, 18; stage IIE, 9; B symptoms present, 10; elevated serum lactate dehydrogenase, 5; and PS 2, 2. With a median follow-up of 32 months, the 2-year overall survival was 78% (95% CI, 57% to 89%). This compared favorably with the historical control of radiotherapy alone (45%). Of the 26 patients assessable for a response, 20 (77%) achieved a complete response, with one partial response. The overall response rate was 81%. The most common grade 3 nonhematologic toxicity was mucositis related to radiation (30%). No treatment-related deaths were observed.

Conclusion

Concurrent chemoradiotherapy using multidrug resistance-nonrelated agents and etoposide is a safe and effective treatment for localized nasal NK/T-cell lymphoma and warrants further investigation.

When do we need central nervous system prophylaxis in patients with extranodal NK/T-cell lymphoma, nasal type?

BACKGROUND

The incidence and risk factors of central nervous system (CNS) invasion is still unclear in extranodal natural killer (NK)/T-cell lymphoma, nasal type.

PATIENTS AND METHODS

We analyzed 208 patients to study the clinical features and outcomes of CNS disease in extranodal NK/T-cell lymphoma.

RESULTS

Twelve patients (5.76%, 12/208) experienced CNS disease during treatment or follow-up period (median 11.62 months, range 0.2-123.2 months). The clinical variables associated with CNS disease were Ann Arbor stage III/IV (15.87%, P <0.001), regional lymph node involvement (10.41%, P = 0.006), group III/IV of NK/T-cell lymphoma prognostic index (NKPI; 10.20%, P = 0.003), high/high-intermediate international prognostic index (9.30%, P = 0.072) and extra-upper aerodigestive primary sites (9.75%, P = 0.008). In multivariate analysis, NKPI retained the strongest statistical power to predict CNS disease (P = 0.007, relative risk 9.289, 95% confidence interval 1.828-47.212) in extranodal NK/T-cell lymphoma.

CONCLUSIONS

Despite extranodal NK/T-cell lymphoma frequently involves paranasal sinus, a routine CNS evaluation and prophylaxis do not seem to be necessary in NKPI group I or II patients due to a very low incidence. Nevertheless, CNS prophylaxis should be considered in NKPI groups III and IV.