Pretreatment EBV-DNA Copy Number Is Predictive of Response and Toxicities to SMILE Chemotherapy for Extranodal NK/T-cell Lymphoma, Nasal Type

Prognostic relevance of pretransplant Deauville score on PET-CT and presence of EBV DNA in patients who underwent autologous stem cell transplantation for ENKTL

High-dose chemotherapy and autologous stem cell transplantation (ASCT) for extranodal natural killer/T-cell lymphoma (ENKTL) is a reasonable option for a subset of patients. The impact of response status, according to positron emission tomography/computed tomography (PET/CT) results and/or presence of circulating EBV DNA prior to ASCT, has not yet been established. We analyzed 27 ENKTL patients with pre-ASCT circulating EBV DNA who had undergone pre-ASCT PET/CT between 2009 and 2014. We classified patients into two groups based on the result of pretransplantation assessment: a favorable risk group (pretransplant five-point Deauville score (DS) of 1-2 based on PET/CT and no detectable EBV DNA) and an unfavorable risk group (DS 1-2 with detectable EBV DNA, DS 3-5 with or without detectable EBV DNA). After a median follow-up of 37 months, overall survival and PFS were significantly different between the two groups (median OS: not reached for favorable risk group vs 7.0 months for unfavorable risk group, P=0.017; median PFS: 16.0 vs 5.0 months, P=0.019). Multivariate analysis revealed that pre-ASCT DS and EBV DNA was the only independent prognostic factor considering stage, IPI and NKPI. Precise assessment of the status of disease before transplantation may provide more benefit from ASCT to ENKTL patients.

Extranodal NK/T-cell lymphoma, nasal type, manifesting as rapidly progressive dementia without any mass or enhancing brain lesion

Among the many potential etiologies for rapidly progressive dementia (RPD), primary central nervous system extranodal NK/T-cell lymphoma, nasal-type (ENKL) is a rare entity. We present the first reported case of autopsy-proven RPD due to ENKL without any mass or enhancing lesion of the brain. A 54-year-old immunocompetent man presented with RPD, myoclonus and ataxia. The mini-mental state examination (MMSE) score was 22/30. His brain MRI revealed progressive brain atrophy without gadolinium enhancement or mass lesion. Five months after the initial evaluation, cognitive impairment further worsened with an MMSE score of 3/30. At the advanced stage, lumbar MRI showed swollen cauda equina with gadolinium enhancement. The number of Epstein-Barr virus (EBV) DNA in cerebrospinal fluid had gradually increased. Twelve months after onset, the patient died of respiratory failure. Pathological findings revealed that lymphoma cells had diffusely invaded the meninges, parenchyma of the brain, spinal cord and cauda equina. Cells were positive for CD3, CD56 and EBV-encoded small RNAs and negative for CD20. No evidence of malignancy was identified in the visceral organs. This report indicates that ENKL should be recognized as one of the rare causes of RPD. Early testing for EBV-DNA in cerebrospinal fluid and imaging of cauda equina would be useful diagnostic tools.

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.

Cytotoxic Molecule-positive Epstein-Barr Virus-associated Peripheral T-cell Lymphoma in a 20-Month-old Child: A Case Report and Review of the Literature

Peripheral T-cell lymphoma (PTCL) is rare in children. Expression of cytotoxic molecules (CM) in nodal PTCL has unique clinicopathologic features, including an Epstein-Barr virus (EBV) association. However, CM+, EBV-associated PTCL is extremely rare in the childhood, with only 1 study having been reported to date, including both pediatric and adult patients. We report a case of CM+ PTCL in a 20-month-old boy with left neck lymphadenopathy as well as multiple visceral lesions. A biopsied lymph node was diffusely infiltrated by atypical lymphoid cells with a CD4/CD8, granzyme B+, perforin+, and TIA-1+ phenotype, and EBV positivity by in situ hybridization. Rearrangements of the TCR γ-chain and β-chain genes were demonstrated by polymerase chain reaction. Ancillary genetic studies detected trisomy 2, trisomy 10, a structurally abnormal 6p, and additional copies of the IRF4 gene. Multiple bone marrow biopsies failed to show any evidence of tumor, histiocytic hyperplasia, or hemophagocytosis. This lesion was therefore diagnosed as "CM+, EBV-associated high-grade peripheral T-cell lymphoma." After 5 cycles of chemotherapy, the patient was in remission 8 months following initial diagnosis. To our knowledge, this represents the youngest child with this rare tumor in the published literature, and showing an unusually favorable initial response to therapy.

Management of advanced NK/T-cell lymphoma

NK/T-cell lymphomas are aggressive malignancies, and the outlook is poor when conventional anthracycline-containing regimens designed for B-cell lymphomas are used. With the advent of L-asparaginase-containing regimens, treatment outcome has significantly improved. L-asparaginase-containing regimens are now considered the standard in the management of NK/T-cell lymphomas. In advanced diseases, however, outcome remains unsatisfactory, with durable remission achieved in only about 50% of cases. Stratification of patients with advanced NK/T-cell lymphomas is needed, so that poor-risk patients can be given additional therapy to improve outcome. Conventional presentation parameters are untested and appear inadequate for prognostication when L-asparaginase-containing regimens are used. Recent evidence suggests that dynamic factors during treatment and interim assessment, including Epstein-Barr virus (EBV) DNA quantification and positron emission tomography computed tomography findings, are more useful in patient stratification. The role of high-dose chemotherapy and haematopoietic stem cell transplantation requires evaluation in an overall risk-adapted treatment algorithm.

Long-term Outcome of Extranodal NK/T Cell Lymphoma Patients Treated With Postremission Therapy Using EBV LMP1 and LMP2a-specific CTLs

Extranodal NK/T-cell lymphoma (ENKTCL) is associated with latent Epstein-Barr virus (EBV) infection and frequent relapse even after complete response (CR) to intensive chemotherapy and radiotherapy. The expression of EBV proteins in the tumor provides targets for adoptive immunotherapy with antigen-specific cytotoxic T cells (CTL). To evaluate the efficacy and safety of EBV latent membrane protein (LMP)-1 and LMP-2a-specific CTLs (LMP1/2a CTLs) stimulated with LMP1/2a RNA-transferred dendritic cells, we treated 10 ENKTCL patients who showed complete response to induction therapy. Patients who completed and responded to chemotherapy, radiotherapy, and/or high-dose therapy followed by stem cell transplantation (HDT/SCT) were eligible to receive eight doses of 2 × 10⁷ LMP1/2a CTLs/m². Following infusion, there were no immediate or delayed toxicities. The 4-year overall survival (OS) and progression-free survival (PFS) were 100%, and 90% (95% CI: 71.4 to 100%) respectively with a median follow-up of 55·5 months. Circulating IFN-γ secreting LMP1 and LMP2a-specific T cells within the peripheral blood corresponded with decline in plasma EBV DNA levels in patients. Adoptive transfer of LMP1/2a CTLs in ENKTCL patients is a safe and effective postremission therapeutic approach. Further randomized studies will be needed to define the role of EBV-CTLs in preventing relapse of ENKTCL.

The Biology and Clinical Utility of EBV Monitoring in Blood

Epstein-Barr virus (EBV) DNA in blood can be quantified in peripheral blood mononuclear cells, in circulating cell-free (CCF) DNA specimens, or in whole blood. CCF viral DNA may be actively released or extruded from viable cells, packaged in virions or passively shed from cells during apoptosis or necrosis. In infectious mononucleosis, viral DNA is detected in each of these kinds of specimens, although it is only transiently detected in CCF specimens. In nasopharyngeal carcinoma, CCF EBV DNA is an established tumor marker. In EBV-associated Hodgkin lymphoma and in EBV-associated extranodal NK-/T-cell lymphoma, there is growing evidence for the utility of CCF DNA as a tumor marker.

[Extranodal NK/T-cell lymphoma, nasal-type, revealed by cutaneous breast involvement]

BACKGROUND

Extranodal NK/T-cell lymphoma (ENKTL) is a rare form of non-Hodgkin's lymphoma and carries a poor prognosis. Depending on the primary sites of anatomical involvement, it is subcategorized into nasal or extra-nasal ENKTL. Cutaneous involvement is the second localization reported for these lymphomas.

PATIENTS AND METHODS

A woman was admitted for erythematous infiltrative patches on the breasts having an ulcerative course. Cutaneous histopathology showed a dense, diffuse infiltrate of atypical lymphocytes. Immunohistochemistry revealed expression of specific markers for NK-cells and of cytotoxic molecules (TIA-1, granzyme B and perforin), lack of expression of T-cell markers (except positivity of cytoplasmic CD3 and CD2), and the presence of EBV-DNA in lymphoma cells. Positron emission tomography-computed tomography revealed sub- and supra-diaphragmatic multi-organ involvement (kidneys, breasts, stomach, duodenum, lungs, pleural cavity, uterus, bones). No bone marrow infiltration was noted. PCR (polymerase chain reaction) showed high circulating levels of EBV-DNA in peripheral blood. A systemic nasal-type ENKTL was diagnosed. A chemotherapy regimen including high-dose methotrexate, oxaliplatin, gemcitabine, L-asparaginase and dexamethasone was started. Despite good initial therapeutic response, the outcome was rapidly fatal with bone marrow involvement and multi-organ failure.

DISCUSSION

Major cutaneous manifestations of ENKTL comprise erythematous infiltrative patches mimicking panniculitis or cellulitis and evolving towards ulceration or necrosis. Subcutaneous nodules may also be noted. Late diagnosis at an advanced stage accounts for the poorer prognosis in extra-nasal ENKTL. In the advanced stages, treatment is based on a chemotherapy regimen including L-asparaginase, possibly followed by autologous or allogeneic hematopoietic stem cell transplantation.

Prognostic biomarkers in patients with localized natural killer/T-cell lymphoma treated with concurrent chemoradiotherapy

Concurrent chemoradiotherapy has become one of the standard management approaches for newly diagnosed localized nasal natural killer (NK)/T-cell lymphoma (NKTCL). Few data are available on the prognostic biomarkers of NKTCL among patients treated with concurrent chemoradiotherapy. To evaluate the prognostic significance of immunophenotypic biomarkers for patients treated with concurrent chemoradiotherapy, latent membrane protein 1 (LMP1), cutaneous lymphocyte antigen (CLA) and cell origin were examined in samples from 32 patients who were enrolled in the Japan Clinical Oncology Group 0211 trial and treated with concurrent chemoradiotherapy. LMP1 and CLA were positive in 66% (19/29) and 29% (9/31) of the cases examined, respectively. The median follow-up duration was 68 months (range, 61–94). The patients with LMP1-positive tumors showed a better overall survival (OS) than the patients with LMP1-negative tumors (hazard ratio, 0.240; 95% confidence interval [CI], 0.057–1.013; 80% CI, 0.093–0.615; P = 0.035). All five patients with LMP1-negative tumors who experienced disease progression died of lymphoma, and both patients with local failure had LMP1-negative tumors. There was no significant difference in OS according to CLA expression. A total of 27 (84%) cases were of NK-cell origin, two were of αβ T-cell origin and three were of γδ T-cell origin. In contrast to those with tumors of NK-cell origin, all five patients with NKTCL of T-cell origin were alive without relapse at the last follow up. Our results indicate that LMP1 expression is a favorable prognostic marker and suggest that a T-cell origin of the tumor may be a favorable prognostic marker for patients with localized NKTCL treated with concurrent chemoradiotherapy.

EBV-related lymphomas: new approaches to treatment

In the treatment of Epstein-Barr virus (EBV)-related lymphomas, there are few therapies specifically targeted against the latent virus within these tumors; in most cases the treatment approach is not different than the approach to EBV-negative lymphomas. Nonetheless, current and emerging therapies focused on exploiting aspects of EBV biology may offer more targeted strategies for EBV-positive lymphomas in the future. Conceptually, EBV-specific approaches include bolstering the antiviral/antitumor immune response with vaccines or EBV-specific cytotoxic T-lymphocytes, activating lytic viral genes to render the tumor cells susceptible to antiviral therapies, and inhibiting the downstream prosurvival or antiapoptotic pathways that may be activated by latent EBV proteins. EBV-specific cytotoxic T-cell infusions have proven effective in EBV-related posttransplantation lymphoproliferative disorder (EBV-PTLD) and expanding such adoptive immunotherapies to other EBV-related malignancies is an area of active research. However, other EBV-related lymphomas typically have more restricted, less immunogenic arrays of viral antigens to therapeutically target with adoptive immunotherapy compared with EBV-PTLD. Furthermore, the malignant EBV-positive tumor cells of Hodgkin lymphoma are scattered amid a dense infiltrate of regulatory T-cells, macrophages, and other cells that may dampen the antitumor efficacy of adoptive immunotherapy. Strategies to overcome these obstacles are areas of ongoing preclinical and clinical investigations. Some emerging approaches to EBV-related lymphomas include the coupling of agents that induce lytic viral replication with antiherpesvirus agents, or the use of small molecule inhibitors that block signaling pathways that are constitutively activated by EBV. EBV vaccines seem most promising for the treatment or prevention of EBV-related malignancies, rather than the prevention of primary EBV infection. EBV vaccine trials in patients with residual or low-bulk EBV-related malignancies or for the prevention of EBV-PTLD in EBV-seronegative patients awaiting solid organ transplantation are ongoing.

[Radiation therapy of sinonasal natural killer/T-cell lymphoma]

Natural killer (NK)/T-cell lymphoma are part of lymphoproliferative diseases, they are rare in Europe and the United States but relatively common in Asia and South America. Natural killer (NK)/T-cell lymphoma present clinically as destructive lesions of the upper aerodigestive tract with perforation of deep structures of the face, destruction of the palate or an invasion of orbits. Treatment modalities of these lymphomas are still discussed because of the lack of available studies and the rarity of this disease. Radiotherapy provides a rapid control of the disease and is positioned as a major treatment of localized stages of NK/T-cell lymphoma of the nasal cavity. We therefore studied the different forms of radiation therapy in the early stages of nasal NK/T-cell lymphoma.

Neurolymphomatosis in a patient with extranodal NK/T-cell lymphoma, nasal-type: a case report and literature review

A 47-year-old man presented with a fever and lower extremity paresthesia. A physical examination revealed sensory deficits in the left hand, distal arm and right sole. A bone marrow aspiration demonstrated infiltration of extranodal NK/T-cell lymphoma, nasal type, and (18)F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) disclosed extensive involvement of the peripheral nerves. These findings were consistent with a diagnosis of neurolymphomatosis (NL). The lymphoma progressed soon after the patient underwent cord blood transplantation, and he died on day 33 after transplantation. NL is a rare manifestation of lymphoma characterized by infiltration of the peripheral nerves, leading to neuropathy. It is an increasingly recognized entity and can be the first indication of lymphoma.

Pathogenesis and treatment of extranodal natural killer/T-cell lymphoma

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKL) is one of the uncommon subtypes of malignant lymphoma, and predominantly occurs in the nasal or paranasal areas and less frequently in the skin. Previously, its prognosis was poor due to the expression of P-glycoprotein, which actively exports several anticancer agents outside the lymphoma cells. However, in recent years, novel therapeutic approaches such as simultaneous chemoradiotherapy or l-asparaginase-based regimens including SMILE (steroid, methotrexate, ifosfamide, l-asparaginase, and etoposide) improved the response to therapy and survival of ENKL patients. Epstein-Barr virus (EBV) is present in lymphoma cells of almost all patients, accounting for the pathogenesis of ENKL. Fragmented EBV-DNA is released from tumor cells, and can be detected in the peripheral blood of patients. The EBV-DNA copy numbers are associated with tumor burden, and can predict the prognosis of ENKL, as well as the toxicity against chemotherapy. Based on this recent progress, ENKL is currently categorized as a lymphoma with intermediate prognosis, but the overall treatment results are not satisfactory. Further improvement of the prognosis of ENKL is therefore warranted, including the optimal use of hematopoietic stem cell transplantation (HSCT).

Retrospective study of modified SMILE chemotherapy for advanced-stage, relapsed, or refractory extranodal natural killer (NK)/T cell lymphoma, nasal type

Extranodal natural killer/T cell lymphomas, nasal type (ENKLs), which are a group of non-Hodgkin lymphomas with poor prognoses, are much more common in China than in Western countries. Here, we retrospectively assessed the impact of two treatment regimens on clinical response and survival among 42 ENKL patients. All patients were diagnosed with stage IV, relapsed, or refractory ENKL. Twenty patients received modified SMILE (consisting of L-asparaginase, methotrexate, ifosphamide, etoposide, and dexamethasone) chemotherapy, and 22 control patients received CHOP (consisting of cyclophosphamide, doxorubicin, vincristine, and prednisone) treatment. Higher complete response (CR) and overall response rates (ORR) (CR 45.0 vs. 13%, ORR 70 vs. 36%) were observed among the patients treated with the modified SMILE regimen (Fisher's exact = 0.040, Pearson χ(2) P = 0.030). Similarly, a higher ORR rate was observed among Epstein-Barr virus-positive patients (ORR 50.0 vs. 18.0%, Fisher's exact = 0.049). The treatment group was also significantly associated with longer overall survival (OS) and progression-free survival (PFS) (Log-rank, P = 0.0341, P = 0.0142, respectively), but OS did not seem to be longer. Treatment-related toxicity was monitored in all patients throughout the protocol. There were no significant differences in the incidence of hematological and non-hematological toxicities between the two groups (P < 0.05), with the exception of peripheral neuropathy (treatment = 0 control = 5, Fisher's exact = 0.049).

The Glasgow Prognostic Score (GPS) as a novel and significant predictor of extranodal natural killer/T-cell lymphoma, nasal type

The Glasgow Prognostic Score (GPS), an inflammation-based prognostic score including C-reactive protein and albumin, shows significant prognostic value in several types of solid tumors. The prognostic value of GPS in lymphoma remains unclear. We performed this study to evaluate the prognostic significance of GPS in extranodal natural killer (NK)/T-cell lymphoma (ENKL). We retrospectively analyzed 164 patients with newly diagnosed ENKL. The prognostic value of GPS was evaluated and compared with that of International Prognostic Index (IPI), Prognostic Index for Peripheral T-cell lymphoma unspecified (PIT), and Korean Prognostic Index (KPI). Patients with higher GPS tended to have more adverse clinical characteristics, lower rates of complete remission (P < 0.001), inferior progression-free survival (PFS, P < 0.001), and inferior overall survival (OS, P < 0.001). Multivariate analysis demonstrated that high GPS, age > 60 years, and elevated LDH were independent adverse predictors of OS. GPS was found superior to IPI, PIT, and KPI in discriminating patients with different outcomes in low-risk groups (all P < 0.05). GPS is an independent predictor of survival outcomes in ENKL. Inflammatory response might play an important role in the progression of ENKL and survival of patients with ENKL.

Clinical implications of plasma Epstein-Barr virus DNA in early-stage extranodal nasal-type NK/T-cell lymphoma patients receiving primary radiotherapy

The clinical value of plasma Epstein-Barr virus (EBV) DNA has not been evaluated in patients with early-stage extranodal nasal-type NK/T-cell lymphoma (NKTCL) receiving primary radiotherapy. Fifty-eight patients with stage I disease and 11 with stage II disease were recruited. High pretreatment EBV-DNA concentrations were associated with B-symptoms, elevated lactate dehydrogenase levels, and a high International Prognostic Index score. EBV-DNA levels significantly decreased after treatment. The 3-year overall survival (OS) rate was 82.6% for all patients. Stage I or II patients with a pretreatment EBV-DNA level of ≤ 500 copies/mL had 3-year OS and progression-free survival (PFS) rates of 97.1% and 79.0%, respectively, compared with 66.3% (P = .002) and 52.2% (P = .045) in patients with EBV-DNA levels of > 500 copies/mL. The 3-year OS and PFS rates for patients with undetectable EBV-DNA after treatment was significantly higher than patients with detectable EBV-DNA (OS, 92.0% vs 69.8%, P = .031; PFS, 77.5% vs 50.7%, P = .028). Similar results were observed in stage I patients. EBV-DNA levels correlate with tumor load and a poorer prognosis in early-stage NKTCL. The circulating EBV-DNA level could serve both as a valuable biomarker of tumor load for the accurate classification of early-stage NKTCL and as a prognostic factor.