Extranodal natural killer/T-cell lymphoma: current concepts in biology and treatment

Primary spinal extranodal NK/T-cell lymphoma diagnosed by fine-needle aspiration and core biopsy

We report an extremely rare case of primary spinal extranodal NK/T-cell lymphoma (PSENKTL). A 54-year-old man presented with fever of unknown etiology for 2 months, with clinical evidence of hemophagocytic lymphohistiocytosis. Imaging studies revealed multiple spinal lesions without evidence of disease in other body sites. Fine-needle aspiration and core biopsy (FNACB) of a paraspinal mass showed a monotonous population of intermediate lymphocytes with abundant cytoplasm with fine granules, round to slightly irregular nuclei, and inconspicuous nucleoli. Core biopsy revealed diffuse infiltration by cells with a NK cell phenotype, positive Epstein-Barr virus-encoded small RNA, and negative T-cell receptor gene rearrangement. Bone marrow biopsy showed the presence of hemophagocytosis without evidence of lymphoma. The disease disseminated to the small bowel late in the clinical course and the patient died shortly after admission. This unusual case was diagnosed by FNACB and raised awareness of ENKTL as a differential diagnosis in spinal lesions.

Rhino-Orbital-Cerebral Mycosis and Extranodal Natural Killer or/and T-Cell Lymphoma, Nasal Type

Background

Extranodal natural killer/T-cell lymphoma, nasal type is a syndrome of middle face destruction with an association to Epstein-Barr virus. Fungi have been recovered from the diseased tissue now and then but were often seen as a lymphoma-associated secondary infection. However, there are ENKTL-NT cases with the recoveries of fungi and complete recovery with antifungal therapy, which are quite similar to rhino-orbital-cerebral mycosis (ROCM) that often confuses the physicians.

Methods

We searched Medline for English-language manuscripts limited to “human” and “case reports,” “letters,” “reviews,” and “clinical conferences” from 1966 to 2022. We used MeSH terms “lymphoma, extranodal nk-t-cell” [MeSH Terms] or “lethal midline granuloma” [MeSH Terms], in combination with MeSH terms “microbiology” [subheading] or “microbiology” [all fields] or “fungi” [all fields] or “fungi” [MeSH Terms] for ENKTL-NT with infections. We used MeSH terms “Mycoses” in combination with “Nose” [Mesh] OR “Orbital Diseases” [Mesh] for rhino-orbital-cerebral fungal infections.

Results

We appraised 149 included articles and extracted references related to ENKTL-NT and/or ROCM. Themes and subcategories were subsequently derived. Our findings revealed that ROCM and ENKTL-NT are characterized by progressive and destructive ulcers in the midline face or rhino-orbital structures. ROCM is mainly caused by fungi in the order of Mucorales, and ENKTL-NT is usually associated with Epstein-Barr virus and sometimes fungi. Radiologically, both are characterized by non-specific features of sinusitis, soft tissue infection, and necrosis. Pathologically, ROCM and ENKTL-NT share the same characteristics of inflammation, necrosis, and granuloma. ROCM is characterized by the detection of fungi in tissue, while ENKTL-NT is typically positive for NK/T-cell markers and cytotoxic granule-associated proteins, proliferation, and vascular damage of angioinvasion, which could be incited by Mucor irregularis and Rhizopus arrhizus in patients and mice.

Conclusion

ENKTL-NT and ROCM share many similarities in clinical presentations, radiology, and histopathology, and might have the same etiology. This may explain why the two diseases are tangled together in the reported cases, and suggests the role that the fungi may play in the development of these ENKTL-NT/ROCM diseases. The reason why ENKTL-NT and ROCM are sometimes confused is that the main pathogens of ROCM, Mucor irregularis and Rhizopus arrhizus, are the fungal causative agents of ENKTL-NT.

Cutaneous T-cell lymphoma in Asian patients: a multinational, multicenter, prospective registry study in Asia

Cutaneous T-cell lymphomas (CTCLs) are a group of T-cell lymphomas with low incidence. Due to their indolent characteristics, treatment strategies have not yet been established for advanced CTCLs. In this study, relative incidence of CTCLs in Asia was estimated and the therapeutic outcomes presented based on various treatments currently used in clinics for advanced CTCLs. As part of a prospective registry study of peripheral T-cell lymphoma (PTCL) conducted across Asia, including Korea, China, Taiwan, Singapore, Malaysia, and Indonesia, subgroup analysis was performed for patients with CTCLs. Among 486 patients with PTCL, 37 with CTCL (7.6%) were identified between April 2016 and February 2019. Primary cutaneous ALK-negative anaplastic large cell lymphoma (ALCL, 35.1%) was the most common subtype. With a median follow-up period of 32.1 months, median progression-free survival (PFS) was 53.5 months (95% CI 0.0-122.5), and overall survival was not reached. 14 patients (48.2%) underwent subsequent treatment after the first relapse, but the response rate was 20% with a PFS of 2.2 months (95% CI 0.3-4.0). Six patients received autologous stem cell transplantation (auto-SCT). However, auto-SCT did not result in better outcomes. Additional studies are needed on standard care treatment of advanced or refractory and relapsed CTCLs.

Interleukin-6 reverses Adriamycin resistance in nasal NK/T-cell lymphoma via downregulation of ABCC4 and inactivation of the JAK2/STAT3/NF-κB/P65 pathway

Chemotherapy is generally effective for extranodal natural killer (NK)/T-cell lymphoma (ENKTCL), nasal type. Nevertheless, multidrug resistance (MDR) remains a key challenge in treating nasal NK/T-cell lymphoma. Interleukin-6 (IL-6) is reportedly an important regulator of MDR in many cancers, implicating a role of IL-6 in the chemotherapy response. However, the effects and mechanism of IL-6 in nasal NK/T-cell lymphoma remain unclear. Herein, we demonstrated that the IL-6 serum level was decreased in nasal NK/T-cell lymphoma patients compared to chronic rhinitis patients. Lower serum levels of IL-6 were closely correlated with Ki67 expression and patient survival. ATP-binding cassette (ABC) drug transporter ABCC4 in patients was abnormally upregulated. IL-6 significantly inhibited resistance to Adriamycin (ADM) in ADM-resistant SNK-6 cells (SNK-6/ADM). Moreover, IL-6 resulted in cell cycle arrest and led to apoptosis in SNK-6/ADM cells. Furthermore, IL-6 decreased ABCC4, p-JAK2, p-STAT3, and phospho-NF-κB p65 expression in SNK-6/ADM cells. IL-6 in combination with ADM inhibited tumor growth and increased the survival of SNK-6/ADM xenograft mice. In conclusion, our findings suggest that IL-6 can inhibit the upregulation of ABCC4 and inactivate the JAK2/STAT3/NF-κB/P65 pathway to sensitize NK/T-cell lymphoma to ADM, indicating that combination therapy with IL-6 and other chemotherapeutic drugs may be effective in reversing acquired resistance in nasal NK/T-cell lymphoma.

Case Report: Rhizopus arrhizus Rhino-Orbital-Cerebral Mycosis and Lethal Midline Granuloma: Another Fungal Etiological Agent

Objective: Both rhino-orbital-cerebral mycosis and lethal midline granuloma (LMG) may result in midline destruction. LMG has now been generally considered as a natural killer/T cell lymphoma, nasal type (ENKTL-NT) with an association of EBV. Fungi have been detected from the diseased tissues now and then but are often considered as lymphoma-associated infections. We previously reported an ENKTL-NT case with Mucor irregularis, which played a causal role in the disease and was involved in the overexpression of Ki67 and CD56 in the mouse experiment. The present study describes a chronic Rhizopus arrhizus infection with immunological parameters that are closely similar to LMG. We aim to explore the relationship of another Mucorales fungus, R. arrhizus, and LMG in a patient and in mice. Methods: Case study and mouse infection modules were designed for our observation. A 35-year-old man with midline face ulcers which was clinically suspected as LMG was selected. Biopsy specimens were sent for lymphoma diagnosis and microbiological detection. The isolated fungus was tested in an ICR mouse model for mycological and histological analyses. Results: Five tissue samples yielded Rhizopus arrhizus. In the pathology, characteristic inflammation, necrosis, and granulation with thin-walled hyphae are observed. Immunohistochemistry showed NK/T cell infiltration (CD3+, CD8+, TIA1+, GZMB+, PRF+, individual CD56+) with hyperplasia (Ki67+) and angioinvasion. The patient recovered completely with amphotericin B. In the murine experiment, R. arrhizus caused angioinvasion with NK/T cell infiltration (CD3+, CD56+, TIA1+, GZMB +, PRF+) with proliferation (Ki67+) and was re-isolated from the infected host. Conclusions: We here describe a mid-face destruction patient, which was diagnosed by the top pathologists in China according to the current criteria of NK/T cell lymphoma, with a negative result for EBV and positive result for R. arrhizus. With a then developed mouse experiment, the R. arrhizus in the diseased lesions was responsible for the NK/T cell infiltration (CD3+, CD8+, CD56+, TIA1+, GZMB+, PRF+), proliferation (Ki67+), and angioinvasion, suggesting another fungal etiological agent for LMG, which could be eradicated with amphotericin B. Limitations: The sample size is not sufficient for statistical analysis. However, our findings are suggestive for the role fungus plays in LMG.

Extra-Nodal, Nasal, Natural Killer T-Cell Lymphoma Treated With a Checkpoint Inhibitor: A Case Report of a Sustained Complete Response

Extra-nodal natural killer T-cell lymphoma (ENKTL) is a rare and aggressive hematologic malignancy found in the nasal cavity and adjacent locations in 80% of cases, accounting for approximately 10% of non-Hodgkin lymphoma (NHL) and 0.4% of all cancers. Prognosis is typically poor and depends on stage, location, age, and tumor markers for targeted therapy, which is reserved for relapsed/refractory ENKTL. Of those, advanced clinical stage, higher Prognostic Index (PI), nodal involvement, Ki-67 expression, large cells, local tumor invasiveness, and circulating Epstein-Barr virus (EBV)-DNA levels are predictive of worse survival. Here, we present a rare case of a patient in remission 30 months after diagnosis of ENKTL following a sustained complete response to pembrolizumab, an immune checkpoint inhibitor targeting the programmed death-1 (PD-1) receptor.

Comprehensive analysis of peripheral T-cell and natural killer/T-cell lymphoma in Asian patients: A multinational, multicenter, prospective registry study in Asia

Background

Peripheral T-cell lymphomas (PTCLs) are uncommon and their frequency is regionally heterogeneous. Several studies have been conducted to evaluate the clinical features and treatment outcomes of this disease entity, but the majority of these were conducted in limited areas, making it difficult to comprehensively analyze their relative frequency and clinical features. Furthermore, no consensus treatment for PTCLs has been established. Therefore, we conducted an Asia-specific study to understand the relative frequency of PTCLs and assess treatments and their outcomes in Asian patients.

Methods

We performed a multinational, multicenter, prospective registry of adult patients with PTCLs that was named as the International Cooperative non-Hodgkin T-cell lymphoma prospective registry study where thirty-two institutes from six Asian countries and territories (Korea, China, Taiwan, Singapore, Malaysia, and Indonesia) participated.

Findings

A total of 486 patients were registered between April 2016 and February 2019, and more than a half of patients (57%) had stage III or IV. Extranodal natural killer (NK)/T- cell lymphoma was the most common subtype (n = 139,28.6%), followed by angioimmunoblastic T-cell lymphoma (AITL, n = 120,24.7%), PTCL-not otherwise specified (PTCL-NOS, n = 101,20.8%), ALK-positive anaplastic large cell lymphoma (ALCL, n = 34,6.9%), and ALK-negative ALCL (n = 30,6.2%). The median progression-free survival (PFS) and overall survival (OS) were 21.1 months (95% CI,10.6-31.6) and 83.6 months (95% CI, 56.7-110.5), respectively. Upfront use of combined treatment with chemotherapy and radiotherapy showed better PFS than chemotherapy alone in localized ENKTL whereas consolidation with upfront autologous stem cell transplantation (SCT) provided longer PFS in advance stage ENKTL. In patients with PTCLs other than ENKTL, anthracycline-containing chemotherapies were widely used, but the outcome of those regimens was not satisfactory, and upfront autologous SCT was not significantly associated with survival benefit, either. The treatment outcome of salvage chemotherapy was disappointing, and none of the salvage strategies showed superiority to one another.

Interpretation

This multinational, multicenter study identified the relative frequency of each subtype of PTCLs across Asian countries, and the survival outcomes according to the therapeutic strategies currently used.

Funding

Samsung Biomedical Research Institute.

Open-label, single arm, multicenter phase II study of VIDL induction chemotherapy followed by upfront autologous stem cell transplantation in patients with advanced stage extranodal NK/T-cell lymphoma

The clinical outcome of advanced-stage Extranodal NK/T cell lymphoma (ENKTL) patients using conventional chemotherapy is extremely poor. The aim of this study was to investigate the outcomes of advanced-stage ENKTL patients treated with non-anthracycline-based chemotherapy followed by upfront autologous stem cell transplant (ASCT). From 8 institutions, 27 patients were recruited from February 2016 to May 2019. Patients were treated with 4 cycles of VIDL induction chemotherapy. Patients who achieved complete response (CR) or partial response (PR) underwent upfront ASCT. This study is registered with clinicaltrial.gov, # NCT02544425. Twenty patients (74.1%) completed 4 cycles of VIDL induction. The overall response rate of VIDL was 74.1%, including 17 (63.0%) with CR and 3 (11.1%) with PR. Primary toxicity of the induction regimen was grade 3 or 4 neutropenia, and no treatment-related mortality was reported. Seventeen patients proceeded with upfront ASCT, and 9 patients relapsed after ASCT, among whom, 4 was central nervous system (CNS) relapse. The median duration of response was 15.2 months (95% CI, 6.3-24.1 months). This study suggested that VIDL induction chemotherapy followed by upfront ASCT is feasible and effective for the treatment of advanced-stage ENKTL. However, CNS relapse prevention is needed in the treatment of advanced-stage ENKTL.

Calreticulin increases growth and progression of natural killer/T-cell lymphoma

In this study, we investigated the role of calreticulin (CALR) in the pathogenesis of natural killer/T-cell lymphoma (NKTCL). CALR expression was significantly higher in the NKTCL tissues than normal control tissues in the GSE80632 dataset. High CALR expression correlated with poorer overall survival of NKTCL patients (P = 0.0248). CALR mRNA and protein levels were significantly higher in NKTCL cell lines (NK92, SNK6, and SNT8) than normal NK cells. CALR-silenced SNK6 cells generated significantly smaller xenograft tumors in immunodeficient NCG mice than control SNK6 cells. CALR-knockdown NKTCL cells showed significantly less in vitro proliferation and Transwell migration than the controls. CALR knockdown inhibited G1-to-S phase cell cycle progression by increasing the levels of p27 cell cycle inhibitor and reducing the levels of cyclin E2 and cyclin-dependent kinase 2 (CDK2). CALR knockdown inhibited epithelial-to-mesenchymal transition (EMT) by decreasing the levels of β-catenin and TCF/ZEB1 and upregulating E-cadherin. These data demonstrate that CALR regulates the growth and progression of NKTCL cells by modulating G1-to-S cell cycle progression and EMT.

Primary Gastrointestinal Involvement in a Case of Extranodal-Extranasal Natural Killer T Cell Lymphoma

Extra-nasal types of Extra-nodal natural killer cell lymphoma (ENKL) have been known with poorer prognoses than nasal type with the worst responses to treatment. The current work introduces a case of ENKL with GI involvement with no nasal manifestations. We report a 56-year male farmer with fever, productive cough, dyspnea, anorexia, vomiting and chill in addition to malaise and cachexia of three months duration referred to a hospital with acute abdominal pain, and was diagnosed as peritonitis due to perforated terminal ileum ulcer before experiencing surgery as a case of acute abdomen. The pathologic study of the relevant biopsy showed "ulceration and necrosis with dense fibrinoleukocytic exudation and granulation tissue formation. CT scan determined a bilateral mass like haziness which was more likely to be metastatic. The review of the previous pathologic specimens raised Natural Killer/T cell Lymphoma (NKTL), the reason for which we focused on the patient's sinuses and nasal area as well as nasopharynx. There was no finding in examination and endoscopy of sinuses. Pathology also found malignant high grade non-Hodgkin T cell lymphoma in specimens obtained from debridement of ulcer at terminal ileum. It also showed that most of the tumor cells were positive for CD3, CD56, CD8, and LCA but negative for CD19, CD20 and AE1/AE3. Positive reactions for CD30 were shown by some cells. CD56, CD3, and CD8 were expressed by neoplastic cells and CD30 were positive in few cells. Proliferative activity (Ki67 index) was high (60-70%). This was the main base to diagnose an extra-nodal extra-nasal NK/T cell lymphoma. In conclusion, Intestinal changes at middle age, especially in men with nonspecific clinical manifestations is highly advised to be studied pathologically and genetically for T cell types like CD30 positive T cells which are usually engaged in ENKTL.

F-18 Fluorodeoxyglucose Positron-Emission Tomography-Computed Tomography in a Case of Extensive Multi-Organal Extranodal Lymphoma with Cardiac Involvement Mimicking Apical Hypertrophic Obstructive Cardiomyopathy: Staging and Response Evaluation

18F fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT) is a standard imaging tool in staging as well as response evaluation for lymphoma. Here, we present a young male with extensive extranodal lymphoma with cardiac involvement which presented as diffuse myocardial lesion mimicking hypertrophic obstructive cardiomyopathy. ¹⁸F-FDG PET/CT helped in the staging by revealing multiple systemic involvements. Interim PET after three cycles of chemotherapy showed a complete metabolic response to therapy in all the extranodal sites including the cardiac involvement, thus retrospectively confirming the lymphomatous involvement. Previous literature also conforms to the superior role of ¹⁸F-FDG PET/CT in the clinical management of extensive extranodal lymphoma.

Specific Soft-Tissue Invasion and LMP1 Expression Are Potential Indicators of Extranodal NK/T Cell Lymphoma, Nasal Type

BACKGROUND Extranodal NK/T cell lymphoma, nasal type (ENKTL-NT) is difficult to distinguish from nasal polyps and inverted papilloma, leading to its high misdiagnosis ratio. The aim of this study was to investigate its potential prognostic indicators. MATERIAL AND METHODS Kaplan-Meier method was used to calculate overall survival (OS) rate. Cox proportional hazards regression was used to analyze risk ratios (ORs) with 95% confidence intervals (CIs). RESULTS Nasal ala infiltration and nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm were potential prognostic factors for OS (p=0.0323 and 0.0072, respectively). Cox proportional-hazards regression indicated that high LMP1 expression and the nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm were the independent risk factors for poor OS of ENKTL-NT (HR=3.0655, p=0.028; HR=2.3650, p=0.0452, respectively). In the subgroup analysis, the OS rate was lower when the nasal floor thickness >2.0 mm or nasal septum thickness >2.5 mm in the patients who had high expression of LMP1 (p=0.0651), whereas high LMP1 expression increased the risk of worse prognostic outcome in patients with deep infiltration thickness. Thus, high LMP1 expression may contribute to the tissue invasion of ENKTL-NT. CONCLUSIONS Any patient with nasal ala soft-tissue invasion, nasal floor thickness >2.0 mm/nasal septum thickness >2.5 mm on CT imaging or high LMP1 expression should prompt immediate histopathologic diagnosis to rule out ENKTL-NT in clinical practice.

PEG-L-CHOP treatment is safe and effective in adult extranodal NK/T-cell lymphoma with a low rate of clinical hypersensitivity

Background

The combination of chemotherapy and L-asparaginase (L-ASP) treatment significantly increased survival rate in an adult patient with extranodal natural killer (NK)/T-cell lymphoma (NKTCL). However, hypersensitivity reactions of L-ASP in some patients limited its application. Polyethylene glycol-conjugated asparaginase (PEG-ASP) has a lower immunogenicity and longer circulating half-life than unconjugated L-ASP, and has been reported to be effective and well-tolerated in children with acute lymphoblastic leukemia. Cyclophosphamide, hydroxydaunorubicin (doxorubicin), oncovin (vincristine), and prednisolone (CHOP) is the most common chemotherapy for non-Hodgkin lymphoma. In this report, we sought to study the efficacy and safety of PEG-L- CHOP in NKTCL in adult Chinese patients.

Methods

Our study is a prospective, multi-center, open-label clinical trial. Patients with newly diagnosed adult NKTCL and an ECOG performance status of 0 to 2 were eligible for enrollment. Treatment included six cycles of PEG-L-CHOP regimen. Radiotherapy was scheduled after 2–4 cycles of PEG-L-CHOP regimen, depending on the stage and primary anatomic site.

Results

We enrolled a total of 33 eligible patients. All 33 patients completed 170 cycles of chemotherapy combined with radical radiotherapy. The overall response rate was 96.9% (32/33) with 75.8% (25/33) achieving complete responses and 21.2% (7/33) achieving partial responses. The overall survival (OS) at 1, 2, 3-year were 100, 90.61 and 80.54%, respectively. The major adverse effects were bone marrow suppression, reduction of fibrinogen level, liver dysfunction, and digestive tract toxicities. No allergic reaction and no treatment-related mortality or severe complications were recorded.

Conclusions

PEG-L-CHOP chemotherapy in combination radiotherapy is safe and durably effective treatment for adult extranodal NK/T-cell lymphoma with fewer allergic reactions.

This study was approved by the Peking University Beijing Cancer Hospital Ethics Review Committee (reference number: 2011101104). The clinical trial registration number ChiCTR1800016940 was registered on July 07, 2018 at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/index.aspx). The clinical trial was registered retrospectively.

MicroRNA Signatures in Diagnosis and Prognosis of Cutaneous T-Cell Lymphoma

Cutaneous T cell lymphoma (CTCL) can have clinical and histological features resembling benign inflammatory dermatosis and can be difficult to diagnose. Very limited biomarkers are available for CTCL prognosis. We aimed to identify microRNA (miR) signatures to facilitate diagnostic and prognostic evaluations of CTCL. A cross-platform miR microarray identified 10 miRs that were differentially expressed between CTCL and benign inflammatory dermatosis patients. Subsequent reverse transcription polymerase chain reaction validation was used to generate a 5-miR-based diagnosing classifier, which showed high diagnostic accuracy in CTCL (area under the curve = 0.985 and 0.956 for training and testing set, respectively). Association between miR expressions and patient prognosis was studied. miR-155 and miR-200b were significantly associated with overall survival in CTCL patients, outperformed Ki-67. miR expressions were combined with Ki-67 to create a classifier for 5-year overall survival in CTCL patients. Our work provided miR signatures to facilitate CTCL diagnosis and prognosis with satisfying accuracy.

Primary pulmonary extranodal NK/T-cell lymphoma of nasal type misdiagnosed as pneumonia: A case report and literature review

RATIONALE

Primary pulmonary NK/T cell lymphoma is extremely rare, and only a few cases have reported so far. Its diagnosis is mainly dependent on open-lung biopsy.

PATIENT CONCERNS

Here, we report a 44-year-old male who was initially misdiagnosed as having pneumonia according to the clinical characteristics and computed tomography (CT) findings.

DIAGNOSIS

The first lung biopsy indicated a large number of coagulative necrotic lesions, and definite diagnosis was made after the second lung biopsy following non-response to 6-day wide spectrum antibiotic therapy. The second lung biopsy showed the tumor cells were positive for LCA, CD3ε, CD30, TIA-1, Ki67 and negative for CD20, CD56, CD1a, MPO, CK, S-100, desmin, and CD34.

INTERVENTIONS

This patient refused to receive further therapy and died 1 month after confirmed diagnosis.

OUTCOMES

Clinically, it is difficult to differentiate pneumonia from NK/T cell lymphoma in pathology due to the presence of plenty of focal necrosis in primary pulmonary NK/T cell lymphoma.

LESSONS

The diagnosis of primary pulmonary NK/T cell lymphoma should be based on lung biopsy (usually multiple lung biopsies are required), immunohistochemistry and clinical and imaging findings.

A comparison of treatment modalities for nasal extranodal natural killer/T-cell lymphoma in early stages: The efficacy of CHOP regimen based concurrent chemoradiotherapy

This study was designed to evaluate the efficacy of several treatment modalities, including CHOP based concurrent chemoradiotherapy (CCRT), for the patients with stage IE or IIE nasal extranodal NK/T-cell lymphoma (nasal ENKL). The cases were retrieved between 2000 and 2010 (n=94), and were followed to the end of February 2016. The patients were grouped into A (chemotherapy alone; CT alone), B (sequential treatment) and C (CCRT). For those with efficacy evaluation for overall treatment (n=90), CR was attained in 60.0% (18/30), 69.8% (30/43) and 76.5% (13/17) patients in the group A, B and C, respectively. The 5-year OS rate was 35.2%, 41.9% and 70.6% in the group A, B and C, respectively. For patients with early stage diseases (IE and IIE), the ECOG performance status and the Ann Arbor stage were significant prognostic factors for both OS and PFS. Among the stage IE patients, besides the ECOG performance status, three prognostic factors which related to treatments (treatment modalities, efficacy of initial and overall treatment) were significant against OS or PFS. In conclusion, compared to chemotherapy alone and sequential treatment, nasal ENKL patients in early stages, especially stage IE, benefit the most from CHOP based concurrent chemoradiotherapy.

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.

Intratumoral Heterogeneity of Pretreatment 18F-FDG PET Images Predict Disease Progression in Patients With Nasal Type Extranodal Natural Killer/T-cell Lymphoma

PURPOSE

The aim of this study was to investigate whether the textural features of pretreatment F-FDG PET images can predict prognosis for nasal type extranodal natural killer/T-cell lymphoma (ENKTL).

MATERIALS AND METHODS

A retrospective analysis of the pretreatment F-FDG PET images of the patients with newly diagnosed nasal type ENKTL from 2008 to 2013 was conducted. Progression-free survival (PFS) was the main outcome measure. The primary tumor was identified and then delineated using the 40% maximum standardized uptake value (SUVmax) thresholding method. The textural features of the pretreatment F-FDG PET images were extracted. The prognostic significance of the textural features of the PET images were examined using the receiver operating characteristic (ROC) curves and Cox regression analysis. P values <0.05 were considered statistically significant.

RESULTS

In total, 17 patients were enrolled, among whom 11 showed disease progression and 6 died from the disease during the median follow-up period of 27.2 months. Dissimilarity and low-intensity short-zone emphasis (LISZE) were identified as independent predictors of PFS by using the ROC curves and multivariate Cox analysis after adjusting for the clinical variables.

CONCLUSIONS

Dissimilarity and LISZE were the significant predictors of disease progression in patients with nasal type ENKTL and can improve their prognostic stratification.

Orphan diseases of the nose and paranasal sinuses: Pathogenesis - clinic - therapy

Rare rhinological diseases are a diagnostic challenge. Sometimes it takes months or even years from the primary manifestation of the disease until the definitive diagnosis is establibshed. During these times the disease proceeds in an uncontrolled or insufficiently treated way. (Irreversible) damage results and sometimes life-threatening situations occur. The unexpected course of a (misdiagnosed) disease should lead to further diagnostic reflections and steps in order to detect also rare diseases as early as possible. The present paper discusses granulomatous diseases of the nose and paranasal sinuses caused by mycobacteria, treponema, Klebsiella, fungi, and protozoa as well as vasculitis, sarcoidosis, rosacea, cocaine-induced midline destruction, nasal extranodal NK/T cell lymphoma, and cholesterol granuloma. Furthermore, diseases with disorders of the mucociliary clearance such as primary ciliary dyskinesia and cystic fibrosis are presented, taking into consideration the current literature.

LMP1 promotes nasal NK/T-cell lymphoma cell function by eIF4E via NF-κB pathway

Nasal natural killer T-cell lymphoma (NKTL) is a highly malignant tumor that is closely associated with Epstein-Barr virus (EBV) infection. Latent membrane protein 1 (LMP1) is encoded by EBV and plays an important role in EBV-induced cell transformation. Therefore, we assessed the function of LMP1 as a stimulant of NKTL progression and the underlying mechanism. A human EBV-positive NKTL cell line (SNK-6) was transfected with pcDNA3.1-LMP1, LV-LMP1 shRNA or LV-eukaryotic translation initiation factor 4E (eIF4E)-shRNA. Then, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to assess the proliferation of SNK-6 cells, and cell migration and invasion were analyzed by transwell chamber assay. Flow cytometry was used to analyze the cell cycle and apoptosis. The results showed LMP1 was highly expressed in SNK-6 cells compared with control groups. Following pretreatment with LMP1 shRNA, the proliferation of SNK-6 cells was inhibited and resulted in a G0/G1 phase arrest. A reduction in invasion and migration was also observed. LMP1 silencing promoted cell apoptosis. Further mechanistic analysis suggested that LMP1 overexpression induced the expression of eIF4E, while eIF4E-shRNA dramatically attenuated the increase in cell proliferation, invasion, migration and the inhibition of apoptosis triggered by LMP-1 upregulation. Moreover, the effect of LMP1 on eIF4E expression was mediated by the NF-κB pathway. Therefore, this finding may provide a potential target against NKTL.

Pseudoepitheliomatous hyperplasia mimicking invasive squamous cell carcinoma in extranodal natural killer/T-cell lymphoma: a report of 34 cases

AIMS

Pseudoepitheliomatous hyperplasia (PEH) is defined as a pattern of epidermal reaction. However, it has not yet been extensively documented in extranodal natural killer/T-cell lymphoma (ENKTL). The aim of our study was to analyse a series of ENKTLs concomitant with PEH mimicking squamous cell carcinoma (SCC).

METHODS AND RESULTS

We analysed 34 cases of ENKTL with PEH. In our study, the incidence of PEH was 3.8% in ENKTLs diagnosed over a 13-year period. All 34 cases presented with PEH, appearing as tongue-like projections of squamous epithelium into the underlying submucosa/dermis with variable depths and jagged borders. The keratinocytes sometimes showed a minor degree of cytological atypia, mostly in the stratum basale, and keratinocyte necrosis was absent. Atypical mitoses and a high nuclear/cytoplasmic ratio were absent. The submucosa and the squamous cell cords were also permeated by atypical lymphocytes.

CONCLUSIONS

ENKTL can be associated with PEH, and the atypical lymphoid cell population can be highly subtle, and therefore may be easily mistaken for SCC, leading to inappropriate therapy. A correct diagnosis requires awareness and recognition of this pitfall by recognizing the associated conditions listed above, which distinguish PEH from SCC.

Sinonasal lymphoma: case series and review of the literature

BACKGROUND

Sinonasal lymphoma is a rare rhinologic entity. We present a case series and review the literature surrounding the diagnosis and management of this disease.

METHODS

A pathology database spanning 22 years at a tertiary care center was searched for a diagnosis of lymphoma in the paranasal sinuses or the nasal cavity. Seventeen cases were identified, and retrospective chart review was performed.

RESULTS

Maxillary and ethmoid sinuses were affected more frequently (n = 8 patients each) than sphenoid and frontal sinuses (n = 5 patients each). Histologically, the most common type was diffuse large B-cell lymphoma (53%, 9 patients), followed by extranodal natural killer/T-cell lymphoma (ENKL, 21%, 3 patients). Presenting symptoms included nasal obstruction and rhinorrhea (53%, 9 patients) and diplopia (18%, 3 patients); and radiographic imaging demonstrated a discrete mass (59%, 10 patients), sinus opacification (53%, 9 patients), and/or bony erosion (35%, 6 patients). Treatment included chemotherapy alone (71%, 12 patients), chemotherapy and radiation (6%, 1 patient), and radiation alone (6%, 1 patient). The 2-year and 5-year overall survival rates were 75% and 53%, respectively, whereas disease-free 2-year and 5-year survival rates were 70% and 49%, respectively.

CONCLUSION

Lymphoma of the nasal cavity and paranasal sinuses is extremely rare, may mimic benign processes, and may manifest either in an isolated fashion or in conjunction with systemic disease. B-cell lymphomas, a more favorable diagnosis, account for a majority of cases, whereas ENKL is associated with rapid disease progression and death. Chemotherapy and radiation are the main therapies. Histologic diagnosis is of paramount importance, and clinicians must remain cognizant of this entity to differentiate it from other sinonasal malignancies.

Extranodal natural killer/T cell lymphomas with extranasal disease in non-endemic regions are disseminated or have nasal primary: a study of 84 cases from India

Abstract We report a study of 84 extranodal natural killer/T cell lymphomas (ENKTCLs) from India to understand the disease pattern. Sixty-one patients had nasal disease and three had Waldeyer's ring tumors, while 20 had extranasal sites of presentation, namely: cervix (n = 1), oral cavity (n = 3), orbit (n = 3), liver (n = 1), ileum (n = 1), and soft tissue and lymph nodes (n = 9). Staging of patients with extranasal disease revealed that either they had disseminated disease or the nasal mass was missed during the initial staging. Extranasal presentation, performance status (PS), international prognostic index (IPI), Korean prognostic index, marrow involvement, radiotherapy and type of chemotherapy affected overall survival, while lymphopenia, performance status, radiotherapy and type of chemotherapy impacted disease-free survival. In the multivariate analysis, IPI and response to chemotherapy emerged as significant prognostic factors. Thus most patients with extranasal ENKTCL have a nasal lesion or disseminated disease and pure extranasal disease is uncommon in non-endemic regions.

"Sandwich" Chemotherapy (CT) with Radiotherapy (RT) improves outcomes in patients with stage IE/IIE extranodal natural killer (NK)/T-cell Lymphomas

The extranodal natural killer/T-cell lymphoma (ENKTL) shows high local or systemic failure rates when radiotherapy (RT) is taken as the primary treatment, suggesting a role for chemotherapy (CT) added to RT for this disease. However, the appropriate mode of combined modality therapy (CMT) has not been fully defined. A total of one hundred and twenty-one patients with ENKTL receiving sandwich CT with RT were reviewed between January 2003 and August 2012. The primary endpoints were the response rate, progression-free survival (PFS), overall survival (OS), and the relapse rate. After the initial CT, there were 84 (69.4%) patients in CR, 22 (18.2%) patients in PR, 9 (7.4%) patients in SD, and 6 (5%) patients in PD, respectively. At the end of RT, the CR, PR, SD, and PD rates for all patients were 90.9% (n=110), 1.7% (n=2), 4.1% (n=5), and 3.3% (n=4), respectively. After a median follow-up of 42.3 months (3.5~112.3 months), the 5-year PFS was 74.7% (95% CI 70.4%~79.0%), and 5-year OS was 77.3% (95% CI 67.9%~86.7%). Disease progression was documented in 25 (20.7%) patients. The rates of systemic failure, local failure, and regional failure were 18.2%, 5.8%, 1.7%, respectively. Twenty death events (16.5%) were observed for the entire group of patients (18 deaths related to PD). Furthermore, CR to the initial CT and low Korean Prognostic Index (KPI) can independently predict long PFS and OS. The sandwich CMT achieved an excellent outcome for localized ENKTL with acceptable toxicity. We recommend it can be applied as the optimal choice for localized ENKTL.

Extranodal natural killer/T-Cell lymphoma: A population-based comparison of sinonasal and extranasal disease

OBJECTIVES/HYPOTHESIS

Extranodal natural killer/T-cell Lymphoma (ENKTL) is a rare, aggressive malignancy that preferentially affects the paranasal region. This study analyzes the demographic, clinicopathologic, incidence, and survival characteristics of sinonasal ENKTL (SN-ENKTL) and extranasal ENKTL (EN-ENKTL) in a comparative fashion.

STUDY DESIGN

Retrospective analysis.

METHODS

The Surveillance, Epidemiology, and End Results database was queried; 528 cases were available for frequency and incidence analysis, and 473 for survival analysis. Data were examined according to age, gender, race, histology, the presence of systemic (or B) symptoms, treatment, and Ann Arbor stage.

RESULTS

Extranasal disease was a poor prognostic factor (hazard ratio [HR] = 1.69, 95% confidence interval [CI] = 1.30-2.19, P < .05). Patients with EN-ENKTL were older (mean 53.8 vs. 49.9 years, P < .05), most were male (72.5% vs. 59.8%, P < .05), and they were more likely to present with stage IIIE/IV disease (38.33% vs. 18.26%, P < .05). B symptoms were present in 38.41% of the EN-ENKTL group (vs. 22.86%, P < .05), and were a poor prognostic factor in this group only (HR = 1.6593, 95% CI = 1.05-2.62, P < .05). Radiation therapy demonstrated a survival advantage among both groups, especially in early stage disease.

CONCLUSIONS

SN-ENKTL carries a significantly better prognosis than EN-ENKTL, which presents at more advanced stages. Radiation therapy was associated with increased survival in both groups, especially in cases of localized disease.

LEVEL OF EVIDENCE

2b.

Aggressive mature natural killer cell neoplasms: from epidemiology to diagnosis

Mature natural killer (NK) cell neoplasms are classified by the World Health Organization into NK/T cell lymphoma, nasal type (NKTCL), aggressive NK-cell leukemia (ANKCL) and chronic lymphoproliferative disorders of NK-cells, the latter being considered provisionally. NKTCL and ANKCL are rare diseases, with higher prevalence in Asia, Central and South America. Most NKTCL present extranodal, as a destructive tumor affecting the nose and upper aerodigestive tract (nasal NKTCL) or any organ or tissue (extranasal NKTCL) whereas ANKCL manifests as a systemic disease with multiorgan involvement and naturally evolutes to death in a few weeks. The histopathological hallmark of these aggressive NK-cell tumors is a polymorphic neoplastic infiltrate with angiocentricity, angiodestruction and tissue necrosis. The tumor cells have cytoplasmatic azurophilic granules and usually show a CD45(+bright), CD2(+), sCD3(-), cytCD3epsilon(+), CD56(+bright), CD16(−/+), cytotoxic granules molecules(+) phenotype. T-cell receptor genes are in germ-line configuration. Epstein-Barr virus (EBV) -encoded membrane proteins and early region EBV RNA are usually detected on lymphoma cells, with a pattern suggestive of a latent viral infection type II. Complex chromosomal abnormalities are frequent and loss of chromosomes 6q, 11q, 13q, and 17p are recurrent aberrations. The rarity of the NK-cell tumors limits our ability to standardize the procedures for the diagnosis and clinical management and efforts should be made to encourage multi-institutional registries.

Prognostic value of whole-body metabolic tumour volume and total lesion glycolysis measured on ¹⁸F-FDG PET/CT in patients with extranodal NK/T-cell lymphoma

PURPOSE

The aim of this study was to determine whether maximum standardized uptake value (SUVmax), whole-body metabolic tumour volume (WBMTV), and whole-body total lesion glycolysis (WBTLG) measured on pretreatment ¹⁸F-FDG PET/CT can predict prognosis in patients with extranodal natural killer/T-cell lymphoma (ENKTL).

METHODS

We conducted a retrospective analysis of 20 patients with newly-diagnosed ENKTL who underwent pretreatment ¹⁸F-FDG PET/CT. WBMTV and WBTLG were measured automatically using the boundaries of voxels presenting SUV>3.0. Uni- and multivariate analyses for survival and disease progression were performed using clinical variables and PET parameters (SUVmax, WBMTV, and WBTLG).

RESULTS

During the follow-up period (median 26.3 months), 12 patients showed disease progression and 10 patients died from the disease. Receiver operating characteristic curve analysis showed cut-off values for SUVmax, WBMTV and WBTLG of 8.1, 14.4 cm³ and 52.7, respectively. Univariate analysis showed that the International Prognostic Index (IPI) score and PET parameters were significant predictors of overall survival (OS) and progression-free survival (PFS). Multivariate analysis, even after adjustment for the IPI score, showed that high WBMTV was the best predictor of OS and PFS, and high SUVmax and WBTLG were significant predictors of PFS.

CONCLUSION

Our results suggested that the use of PET parameters together with the IPI score may be useful for detailed prediction of prognosis in ENKTL patients. Therefore, despite a lower IPI score, patients with high PET parameter values might be considered candidates for aggressive therapy to improve clinical outcomes.

LMP1 and LMP2A are potential prognostic markers of extranodal NK/T-cell lymphoma, nasal type (ENKTL)

Background

Latent membrane protein (LMP) 1 and LMP2A encoded by Epstein-Barr virus (EBV) are associated with the development of malignancies, but their expression in extranodal NK/T-cell lymphoma, nasal type (ENKTL) and the relationship with clinical characteristics of this disease remain poorly understood. In the present study, we examined the expression of LMP1 and LMP2A in ENKTL, and investigated the correlations between LMP1 and LMP2A expression with clinicopathological characteristics of ENKTL patients.

Methods

Paraffin sections of surgically removed samples from 16 ENKTL patients were analyzed by immunohistochemistry and the related clinicopathological data were collected and analyzed.

Results

Elevated expression (immunohistochemistry score ≥ 4) of LMP1 and LMP2A was detected in the tumor cells of ENKTL. High LMP1 expression was associated with positive B symptoms (p = 0.012), while high LMP2A expression was related to gender (p = 0.029). The expression of both LMP1 and LMP2A showed significant correlations with patients’ overall survival (p = 0.049, p = 0.036).

Conclusion

LMP1 and LMP2A may be prognostic indicators of survival in patients with ENKTL.

Virtual slides

http://www.diagnosticpathology.diagnomx.eu/vs/2443352538545899

Retrospective analysis of treatment outcomes for extranodal NK/T-cell lymphoma (ENKL), nasal type, stage I-IIE: single institute experience of combined modality treatment for early localized nasal extranodal NK/T-cell lymphoma (ENKL)

Extranodal natural killer/T-cell lymphoma (ENKL) is a very aggressive disease frequently involving the nasal cavity and upper aerodigestive tract. We retrospectively reviewed the treatment outcomes and treatment-associated complications of the patients with stage I-II early localized ENKL. A total of 24 patients were included. All patients were treated with combined chemoradiotherapy. Three, sixteen, and five patients were initially treated with radiation therapy, chemotherapy, and surgical procedures, respectively. Nine patients underwent hematopoietic stem cell transplantation (HSCT), and four patients administered immunotherapy with pegylated-interferon alpha. The mean observation time was 71.6 months (range, 29.7-183.6 months). Twenty patients achieved complete remission; thus, the overall response rate was 83.3 %. The 5-year overall survival (OS) and relapse-free survival (RFS) rates were 70.3 % and 62.2 %, respectively. In univariate analysis, HSCT was a significant prognostic indicator for OS and RFS. By combining HSCT, the 5-year OS and RFS rates were 100.0 % vs. 52.5 % (p = 0.018) and 88.9 % vs. 45.7 % (p = 0.045), respectively. Also, absence of B symptoms was a good prognostic factor for RFS, the 5-year RFS rate, 75.0 % vs. 25.0 % (p = 0.010), and B symptoms were significant for RFS in multivariate analysis (odds ratio = 7.4, confidence interval = 1.6~34.1, p = 0.011). However, a total of four cases of grade 3 toxicities were reported. Radiation dose range (≤4,500 vs. >4,500 cGy) was significantly correlated with late complications, as more severe complications occurred more frequently with a radiation dose >4,500 cGy (p = 0.026, in multivariate analysis). For more efficient treatment of ENKL, chemotherapy, HSCT, and/or immunotherapy can be combined with radiation therapy to prolong long-term survival and achieve good local control. Also, lower radiation dose could be administered to avoid severe late complications.

Mucor irregularis infection and lethal midline granuloma: a case report and review of published literature

Mucor irregularis (Rhizomucor variabilis) infection and lethal midline granuloma (LMG) are characterized by progressive swelling, ulceration, and destruction of the central face that is usually fatal. Pathological features are inflammation, necrosis, and granulation. LMG has been called by various names, and in recent years, it has been known as NK/T cell lymphoma. However, diagnosis still relies on the progressive necrosis course rather than malignancy in histology. The disease has long challenged physicians, particularly when it worsens with radiotherapy or chemotherapy but sometimes achieves total remission without anti-malignancy therapies. We describe a 35-year-old man who had typical clinical-pathological symptoms of LMG, which turned out to be primary M. irregularis infection; that was diagnosed by positive tissue culture and fungal elements in histology. The patient was successfully treated with antifungal therapy (liposomal amphotericin B, total 4,600 mg and amphotericin B total 277 mg, over a duration of 70 days). We hereby review current knowledge about the epidemiology, clinical manifestations, radiographic characteristics, and pathologic features of LMG with those of M. irregularis infection and their associations. We conclude that primary M. irregulars infection can mimic the clinico-pathological symptoms of LMG and the condition responds favorably to aggressive antifungal therapy.

PET/CT aids the staging of and radiotherapy planning for early-stage extranodal natural killer/T-cell lymphoma, nasal type: a case series

Extranodal natural killer/T-cell lymphoma (ENKTL), nasal type, is a rare form of non-Hodgkin lymphoma. Treatment of ENKTL primarily relies on radiation; thus, proper delineation of target volumes is critical. Currently, the ideal modalities for delineation of gross tumor volume for ENKTL are unknown. We describe three consecutive cases of localized ENKTL that presented to the Nova Scotia Cancer Centre in Halifax, Nova Scotia. All patients had a planning CT and MRI as well as a planning FDG-PET/CT in the radiotherapy treatment position, wearing immobilization masks. All patients received radiation alone. In two patients, PET/CT changed not only the stage, but also the target volume requiring treatment. The third patient was unable to tolerate an MRI, but was able to undergo PET/CT, which improved the accuracy of the target volume. PET/CT aided the staging of and radiotherapy planning for our patients and appears to be a promising tool in the treatment of ENKTL.

Epstein-Barr virus BART9 miRNA modulates LMP1 levels and affects growth rate of nasal NK T cell lymphomas

Nasal NK/T cell lymphomas (NKTCL) are a subset of aggressive Epstein-Barr virus (EBV)-associated non-Hodgkin's lymphomas. The role of EBV in pathogenesis of NKTCL is not clear. Intriguingly, EBV encodes more than 40 microRNAs (miRNA) that are differentially expressed and largely conserved in lymphocryptoviruses. While miRNAs play a critical role in the pathogenesis of cancer, especially lymphomas, the expression and function of EBV transcribed miRNAs in NKTCL are not known. To examine the role of EBV miRNAs in NKTCL, we used microarray profiling and qRT-PCR to identify and validate expression of viral miRNAs in SNK6 and SNT16 cells, which are two independently derived NKTCL cell lines that maintain the type II EBV latency program. All EBV BART miRNAs except BHRF-derived miRNAs were expressed and some of these miRNAs are expressed at higher levels than in nasopharyngeal carcinomas. Modulating the expression of BART9 with antisense RNAs consistently reduced SNK6 and SNT16 proliferation, while antisense RNAs to BARTs-7 and -17-5p affected proliferation only in SNK6 cells. Furthermore, the EBV LMP-1 oncoprotein and transcript levels were repressed when an inhibitor of BART9 miRNA was transfected into SNK6 cells, and overexpression of BART9 miRNA increased LMP-1 protein and mRNA expression. Our data indicate that BART9 is involved in NKTCL proliferation, and one of its mechanisms of action appears to be regulating LMP-1 levels. Our findings may have direct application for improving NKTCL diagnosis and for developing possible novel treatment approaches for this tumor, for which current chemotherapeutic drugs have limited effectiveness.

Cutaneous T-cell lymphoma: 2011 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Cutaneous T-cell lymphomas are a heterogenous group of T-cell lymphoproliferative disorders involving the skin, the majority of which may be classified as Mycosis fungoides (MF) or Sézary syndrome (SS).

DIAGNOSIS

The diagnosis of MF or SS requires the integration of clinical and histopathologic data.

RISK-ADAPTED THERAPY

Tumor, node, metastasis, and blood (TNMB) staging remains the most important prognostic factor in MF/SS and forms the basis for a "risk-adapted," multidisciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin-directed therapies is preferred, as both disease-specific and overall survival for these patients is favorable. In contrast, patients with advanced-stage disease with significant nodal, visceral, or blood involvement are generally approached with biologic-response modifiers, denileukin diftitox, and histone deacetylase inhibitors before escalating therapy to include systemic, single-agent chemotherapy. Multiagent chemotherapy may be used for those patients with extensive visceral involvement requiring rapid disease control. In highly-selected patients with disease refractory to standard treatments, allogeneic stem-cell transplantation may be considered.

Newly emerging therapies targeting viral-related lymphomas

Gamma-(γ)-herpes virus lymphomas comprise a heterogenous group of B-cell and T-cell neoplasms most commonly associated with Epstein-Barr virus and rarely human herpes virus-8 infection. Adult T-cell leukemia/lymphoma (ATLL) is a unique disease entity caused by the human T-cell lymphotrophic virus, type 1 (HTLV-I), the only retrovirus known to cause cancer in humans. Viral lymphomas behave aggressively and disproportionally affect immunocompromised individuals and those living in underdeveloped regions. These diseases are often difficult to treat with conventional approaches. Despite recent advancements using cytotoxic, lymphoma-specific, and adoptive therapies, the long-term outcome of patients with γ-herpesvirus lymphomas occurring in severely immunocompromised patients and ATLL continues to be poor. Lytic-inducing therapies targeting NF-κB, and viral and tumor cell epigenetic mechanisms afford the advantage of exploiting the intrinsic presence of oncogenic viruses to eradicate infected tumor cells. In this review, viral-related lymphomas and newly emerging clinical approaches targeting viral latency are discussed.

Mainly adrenal gland involving NK/T-cell nasal type lymphoma diagnosed with delay due to mimicking adrenal hemorrhage

A 29-yr-old man, presented with abdominal pain and fever, had an initial computed tomography (CT) scan revealing low attenuation of both adrenal glands. The initial concern was for tuberculous adrenalitis or autoimmune adrenalitis combined with adrenal hemorrhage. The patient started empirical anti-tuberculous medication, but there was no improvement. Enlargement of cervical lymph nodes were developed after that and excisional biopsy of cervical lymph nodes was performed. Pathological finding of excised lymph nodes was compatible to NK/T-cell lymphoma. The patient died due to the progression of the disease even after undergoing therapeutic trials including chemotherapy. Lymphoma mainly involving adrenal gland in the early stage of the disease is rare and the vast majority of cases that have been reported were of B-cell origin. From this case it is suggested that extra-nodal NK/T-cell lymphoma should be considered as a cause of bilateral adrenal masses although it is rare.

Extranodal NK/T-cell lymphoma presenting with primary cardiac involvement

Primary cardiac lymphoma is extremely uncommon. We report a case of a 54 year old Caucasian male with a history of non-small cell lung cancer treated by surgical resection who presented with chest pain and dyspnea on exertion. Computerized tomography (CT) imaging confirmed a 7.8×3.8 cm right atrial soft tissue mass infiltrating the lateral wall of the right atrium, and a 5 cm pericardiophrenic mass. Echocardiography confirmed a moderate pericardial effusion without tamponade physiology. Percutaneous biopsy of the pericardiophrenic mass revealed pathologic features diagnostic of NK/T-cell lymphoma. He received CHOP chemotherapy with some improvement in symptoms, but experienced radiographic progression after 2 cycles. He received palliative involved field radiotherapy but developed new sites of progressive disease within the abdomen and died shortly after completing radiotherapy. NK/T-cell lymphomas are aggressive tumors that may present with unusual extranodal disease sites. Prompt diagnosis with consideration for referral to a specialty center with experience in treatment of these rare tumors may offer the greatest potential for improving treatment outcomes.

Extranodal NK/T-cell lymphoma: toward the identification of clinical molecular targets

Extranodal natural killer (NK)/T-cell lymphoma of nasal type (NKTCL) is a malignant disorder of cytotoxic lymphocytes of NK or more rarely T cells associated with clonal Epstein-Barr virus infection. Extranodal NKTCL is rare in Western countries, but in Asia and Central and South America it can account for up to 10% of non-Hodgkin's lymphomas. It is an aggressive neoplasm with very poor prognosis. Although the pathogenesis of extranodal NKTCL remains poorly understood, some insights have been gained in the recent years, especially from genome-wide studies. Based on our own experience and knowledge of the literature, we here review some of the genomic and functional pathway alterations observed in NKTCL that could provide a rationale for the development of innovative therapeutic strategies.

Primary uterine NK-cell lymphoma, nasal-type: a unique malignancy of a prominent cell type of the endometrium

Natural killer (NK) cells host in the human endometrium with dedicated role in reproductive physiology. Interestingly, malignant transformation of these specialized cells has not been presented thus far. Here we report a primary endometrial NK-cell lymphoma of a 48 year-old patient presenting with irregular bleeding. The endometrial curetting showed a dense lymphomatous infiltrate demonstrating highly infiltrative aggressive features with characteristic angiocentric, partially angiodestructive growth pattern and accompanying focal necroses. The lymphoma cells displayed a CD3ε/CD56/TIA-1/granzyme-B-positive and CD5/CD4/CD8/TCRγδ-negative immunophenotype, proved to be positive for Epstein-Barr virus by EBER in situ hybridization, and revealed no clonal T-cell receptor gene rearrangement. The diagnosis of uterine extranodal NK-cell lymphoma, nasal-type was made. Clinically, the disease was limited to the uterus at diagnosis, but progressed rapidly, and the patient died within 5 months due disseminated lymphoma, irrespective of intensive chemotherapy. Genuine NK-cell lymphomas occurring in the uterus as primary site seem to be rare making the therapeutic decisions extremely complicated.

Treatment of localized extranodal NK/T cell lymphoma, nasal type

Extranodal NK/T cell lymphoma predominantly presents as a localized disease in the upper aerodigestive tract from the nasal cavity to the hypopharynx. Because radiotherapy has better outcomes than chemotherapy with reduced locoregional failure, it should be considered the preferred first-line therapy. However, the addition of chemotherapy is appropriate as part of the initial treatment because of the frequent systemic progression or relapse after radiotherapy. At present, the combination of radiotherapy and chemotherapy can be considered an effective treatment option, and the promising results of recent prospective studies with concurrent chemoradiotherapy support this treatment strategy. In contrast, intensive chemotherapy should be considered as initial treatment for patients with tumors in non-upper-aerodigestive-tract sites, such as skin or intestine because they usually progress to systemic disease. Likewise, for patients with poor prognostic factors, such as a high NK lymphoma prognostic index, autologous stem cell transplantation during remission and additional treatments with central nervous system prophylaxis may be beneficial. However, the precise role of these treatments needs to be clarified further by prospective clinical trials. Thus, a prospective study is warranted to explore a risk-adapted treatment strategy of applying initial chemoradiotherapy and additional consolidation treatments.

Natural killer cell lymphoma in a pediatric patient with inflammatory bowel disease

Tumor necrosis factor α (TNF-α) antibody agents are an effective therapy for the treatment of inflammatory bowel disease (IBD); however, because of the potential for immune suppression with these drugs, TNF-α antibody agents can increase the risk of malignancy. We report here the case of an 11-year-old boy who presented with bowel obstruction. He also had a history of periodic fever, aphthous stomatitis, and cervical adenitis (PFAPA). Intestinal inflammation continued and impaired his quality of life; he was diagnosed with IBD of an undetermined type (IBD-U). Symptoms improved with infliximab, but he developed elevated transaminase levels with hepatosplenomegaly 1 year after scheduled infusions. Skin biopsy revealed an atypical lymphoid infiltrate consistent with an Epstein-Barr virus (EBV)-positive natural killer (NK)/T-cell lymphoma with associated hemophagocytic lymphohistiocytosis. Bone marrow biopsy revealed a similar EBV-positive lymphoid infiltrate consistent with an NK/T-cell lymphoma. EBV-positive tissue was present in gastrointestinal biopsies. Flow-cytometric analysis revealed an atypical, clonal NK-cell population, and biopsy specimens from several tissue sites tested positive for CD3, CD56, and CD30. The patient died soon after the diagnosis was made. This patient developed an EBV-driven malignancy while receiving infliximab. All patients with IBD who receive infliximab should be monitored for malignancy, especially young patients. This case underscores the need for future studies to better understand the biology of lymphoproliferative disorders.