Extranodal NK/T-cell lymphoma: diagnosis and treatment cues

[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.

Treatment outcome of radiotherapy alone versus radiochemotherapy in IE/IIE extranodal nasal-type natural killer/T cell lymphoma: a meta-analysis

BACKGROUND

Previous studies have revealed conflicting findings concerning the efficacy of radiotherapy (RT) and radiochemotherapy (RCT) in IE/IIE extranodal nasal-type natural killer/T cell lymphoma (ENKTL). In this study, we conducted a comprehensive meta-analysis to address this issue.

METHODS

We systematically searched PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), EmBase, BISOS, Clinical Trials and some Chinese databases for relevant studies, and 2 prospective and 15 retrospective studies involving a total of 1595 patients met our inclusion criteria.

RESULTS

The meta-analysis showed no significant differences in complete remission (CR) [odds ratio (OR) 0.85, 95% confidence interval (CI) 0.42-1.72, p = 0.65], 5-year overall survival (OS) [hazard ratio (HR) 1.11, 95% CI 0.85-1.45, p = 0.43] and 5-year progression free survival (PFS) (HR 1.07, 95% CI 0.75-1.53, p = 0.70) in patients who received RT versus RCT. Furthermore, the addition of CT decreased neither systemic failure (SL) (OR 0.75, 95% CI 0.47-1.21, p = 0.24) nor locoregional failure (LF) (OR 1.17, 95% CI 0.68-2.01, p = 0. 57).

CONCLUSIONS

RCT did not have an obvious advantage over RT for treating IE/IIE ENKTL.

Serum ferritin level is prognostic of patient outcome in extranodal NK/T cell lymphoma, nasal type

The objective of the current study was to assess the prognostic factors in patients with extranodal natural killer (NK)/T cell lymphoma, nasal type (ENKL). We retrospectively analyzed 35 patients who were diagnosed with ENKL between 1998 and 2011. The median patient age was 63 years, and the male/female ratio was 22:13; twenty patients had localized ENKL, and 26 had a good Eastern Cooperative Oncology Group performance status (score 0 or 1). B symptoms were present in 17 patients. Twenty-five patients presented with nasal or paranasal lesions, or both. With a median follow-up duration among patients still alive at their last follow-up of 47 months (range 8-93 months), the 3-year overall survival (OS) rate was 44.5 %. Multivariate analysis revealed that advanced disease stage (P = 0.002), the presence of extranasal disease (P = 0.013), and serum ferritin levels greater than 300 ng/ml (P < 0.001) were significant and independent (negative) prognostic factors. High serum ferritin levels were associated with the presence of B symptoms, elevated lactate dehydrogenase levels, and high soluble interleukin-2 receptor levels, but not with clinical stage. Patients with high ferritin levels had a remarkably low remission rate (23 %) and a short OS time (median: 4 months). Serum ferritin level at the time of diagnosis of ENKL was a useful prognostic factor.

Efficacy of gemcitabine combined with oxaliplatin, L-asparaginase and dexamethasone in patients with newly-diagnosed extranodal NK/T-cell lymphoma

There is currently no standard first-line regimen for patients with extranodal natural killer (NK)/T-cell lymphoma (ENKTCL). In this study, we investigated the efficacy and toxicity of gemcitabine (GEM) combined with oxaliplatin (L-OHP), L-asparaginase (L-ASP) and dexamethasone (DXM) (GOLD regimen) as a systemic treatment scheme for newly-diagnosed ENKTCL cases. A total of 55 patients were recruited at the Henan Province Cancer Hospital and the Cancer Center of Sun Yat-sen University between May, 2008 and August, 2012. The GOLD regimen included a 14-day treatment cycle with GEM (1,000 mg/m²) on day 1, L-OHP (100 mg/m²) on day 1, L-ASP (10,000 U/m²) on days 1-5 and DXM (20 mg b.i.d.) on days 1-4. The response rate, survival rate and treatment toxicity were analyzed. The overall response rate was 91% (48/55) with a complete response in 62% (34/55) and a partial response in 29% (15/55) of the patients. For all patients, the 1-, 2- and 3-year progression-free survival (PFS) rate was 86, 64 and 57% and the overall survival (OS) 91, 80 and 74%, respectively. The 1-year PFS in patients with stage I/II vs. those with III/IV disease was 87 vs. 66% (P<0.001) and the 1-year OS was 98 vs. 75%, respectively (P<0.001). No chemotherapy-related mortality or severe complications were recorded. In conclusion, the GOLD regimen was found to be highly effective and safe for the treatment of patients with newly-diagnosed ENKTCL.

Clinical and otorhinolaryngological aspects of extranodal NK/T cell lymphoma, nasal type

Introduction

Extranodal NK/T-Cell lymphoma, nasal type (NKTLN) is a disease that mainly affects the nasal cavity and the paranasal sinuses. Early nasal symptoms are nonspecific, simulating sinus infection. With disease progression, necrosis of the nasal mucosa increases, hindering histological diagnosis. Thus, multiple biopsies may be necessary until definitive diagnosis. Most studies on NKTLN address the hematological and immunological aspects of the disease.

Objectives

To present data from a Brazilian quaternary hospital, with emphasis on the clinical aspects of the disease, and to correlate the findings with the most recent literature data.

Methods

Case study of seven patient files.

Results

Patients were evaluated on their medical history, number of biopsies necessary, association with Epstein–Barr virus, treatment, and outcome. All patients had nonspecific nasal complaints and underwent at least three cycles of antibiotic therapy. The earlier a biopsy was performed, the fewer biopsies were required to diagnose the disease and start treatment. However, this fact did not translate into better prognosis.

Conclusion

The otolaryngologist plays a fundamental role in the prognosis of NKTLN and can shorten time between symptom onset and treatment of the patient.

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).

The changing landscape of peripheral T-cell lymphoma in the era of novel therapies

Peripheral T-cell lymphomas (PTCLs) are the most common sub-entity of mature T-cell lymphomas, and apart from particular presentations, share a poor prognosis with frequent short-term, agressive, and chemorefractory relapses. Because of the rarity and also the heterogeneity of the disease, we lack randomized clinical trials. However, to date, neither intensification of frontline chemotherapy or autologous transplant has led to any improvement of survival, and the standard CHOP (cyclophosphamide, doxorubicine, vincristine, and prednisone) regimen remains the most employed as induction therapy. In the past few years, new chemotherapeutic agents, with the capability to encompass the resistance to conventional chemotherapy, such as pralatrexate or bendamustine, have been evaluated. Furthermore, identification of cell surface molecular markers (CD52, CD30, CCR4) has led to the development of new monoclonal antibodies. Similarly, the better comprehension of physiopathological mechanisms and detection of deregulated intracellular pathways encouraged the use of novel therapies such as histone deacetylase inhibitors or immunomodulatory drugs. Some of these compounds have been approved for relapse, and are currently evaluated upfront in ongoing clinical trials. Despite these efforts, the global prognosis still remains much inferior to those of B-cell lymphomas, highlighting the necessity of multicenter clinical trials.

Identification of genuine primary pulmonary NK cell lymphoma via clinicopathologic observation and clonality assay

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, is an uncommon lymphoma associated with the Epstein-Barr virus (EBV). It most commonly involves the nasal cavity and upper respiratory tract. Primary pulmonary NK/T cell lymphoma is extremely rare. If a patient with a NK or T-cell tumor has an unusual reaction to treatment or an unusual prognosis, it is wise to differentiate NK from T-cell tumors. The clinicopathologic characteristics, immunophenotype, EBV in situ hybridization, and T cell receptor (TCR) gene rearrangement of primary pulmonary NK cell lymphoma from a 73-year-old Chinese woman were investigated and the clonal status was determined using female X-chromosomal inactivation mosaicism and polymorphisms at the phosphoglycerate kinase (PGK) gene. The lesion showed the typical histopathologic characteristics and immunohistochemical features of NK/T cell lymphoma. However, the sample was negative for TCR gene rearrangement. A clonality assay demonstrated that the lesion was monoclonal. It is concluded that this is the first recorded case of genuine primary pulmonary NK cell lymphoma. The purpose of the present work is to recommend that pathologists carefully investigate the whole lesion to reduce the likelihood that primary pulmonary NK cell lymphoma will be misdiagnosed as an infectious lesion. In addition, TCR gene rearrangement and clonal analysis, which is based on female X-chromosomal inactivation mosaicism and polymorphisms at PGK and androgen receptor (AR) loci, were found to play important roles in differentiating NK cell lymphoma from T cell lymphoma.

VIRTUAL SLIDES

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5205300349457729.

A prospective phase II study of L-asparaginase- CHOP plus radiation in newly diagnosed extranodal NK/T-cell lymphoma, nasal type

PURPOSE

To explore the efficacy and safety of L-asparaginase in newly-diagnosed extranodal nature killer (NK)/T -cell lymphoma (ENKTL), we conducted a prospective phase II study of L-asparaginase, cyclophosphamide, vincristine, doxorubicin and dexamethasone (CHOP-L) regimen in combination with radiotherapy.

PATIENTS AND METHODS

Patients with newly diagnosed ENKTL and an ECOG performance status of 0 to 2 were eligible for enrollment. Treatment included 6-8 cycles of CHOP-L (cyclophosphamide, 750 mg/m(2) day 1; vincristine, 1.4 mg/m(2) day 1 (maximal dose 2 mg), doxorubicin 50 mg/m(2) day 1; dexamethasone 10 mg days 1-8; L-asparaginase 6000 u/m(2) days 2-8). Radiotherapy was scheduled after 4-6 cycles of CHOP-L regimen, depending on stage and primary anatomic site. The primary endpoint was complete response (CR) rate.

RESULTS

A total of 38 eligible patients were enrolled. The median age was 40.5 years (range, 15 to 71 years). Their clinical characteristics were male to female ratio, 24:14; Ann Arbor stage I, 20; II, 11; III, 3; IV, 4. CR and overall response rates were 81.6% (95% CI, 69.3% to 93.9%) and 84.2%, respectively. With a median follow-up of 25 months, the 2-year overall survival, progression-free survival and disease-free survival rates were 80.1% (95%CI, 73.3% to 86.9%), 81% (95%CI, 74.5% to 87.5%) and 93.6% (95%CI, 89.3% to 97.9%), respectively. The major adverse events were myelosuppression, liver dysfunction, and digestive tract toxicities. Grade 3 to 4 leukopenia and neutropenia were 76.3% and 84.2%, respectively. No treatment-related death was observed.

CONCLUSION

CHOP-L chemotherapy in combination with radiotherapy is a safe and highly effective treatment for newly diagnosed ENKTL.

Impact of dexamethasone, etoposide, ifosfamide and carboplatin as concurrent chemoradiotherapy agents for nasal natural killer/T-cell lymphoma

The nasal type of extranodal natural killer (NK)/T-cell lymphoma (NKTCL) is a rare aggressive lymphoma with poor prognosis. The reported 5-year overall survival for patients with localized nasal NKTCL treated with cyclophosphamide, hydroxydaunorubicin, oncovin and prednisone (CHOP) is <50%. Dexamethasone, etoposide, ifosfamide and carboplatin (DeVIC) chemotherapy was designed as a salvage chemotherapeutic regimen for aggressive lymphoma, comprising multidrug resistance (MDR) non-related agents and etoposide, which is considered to be effective against nasal NKTCL. An experimental chemoradiotherapy (CRT) is currently being designed using DeVIC as the concurrent chemotherapeutic regimen for nasal NKTCL. The aim of this study was to examine the initial outcome of this treatment and evaluate its effectiveness and feasibility. Six patients (age range, 29–82 years; median age, 68 years) were treated with CRT using DeVIC between April, 2004 and February, 2010. The median follow-up was 56 months (range, 11–80 months). All patients were administered 3–6 cycles of full-dose DeVIC regimen. The chemotherapy was administered concurrently with radiotherapy (RT) and was repeated every 3 weeks. RT was performed using 4-MV X-ray and the prescription dose was 46–50 Gy/23–25 fx (median, 50 Gy). After treatment, all patients were followed up at our hospital. A complete remission was achieved in 5 patients (83%) at 1 month after treatment. The 5-year overall survival and disease-free survival rates were 100%. No severe adverse effect (grade ≥3) was reported. In conclusion, the initial results of the experimental CRT with DeVIC for this type of aggressive lymphoma were very encouraging. Further investigation is required on concurrent CRT with 50 Gy/25 fx and 3 cycles of DeVIC comprising non-MDR agents and etoposide for nasal NKTCL.

NK/T-cell lymphomas: pathobiology, prognosis and treatment paradigm

The current World Health Organization (WHO) classification includes two types of natural killer (NK)-cell lymphomas: extranodal NK/T-cell lymphoma, nasal type (ENKL), and aggressive NK-cell leukemia (ANKL). These diseases are mostly endemic to East Asia and Latin America. The Epstein-Barr virus (EBV) is usually detected in tumor cells, suggesting that EBV plays an important role in lymphomagenesis. At the site of origin, ENKL can be divided into two major subtypes: nasal and extranasal diseases. The advanced disease presentation, highly aggressive clinical course, and poor prognosis of the latter are analogous to ANKL. It is well known that P-glycoprotein, which is a product of the multi-drug resistance (MDR1) gene, is expressed on neoplastic cells of ENKL or ANKL. This is a major cause of the refractoriness of malignant lymphoma to conventional chemotherapeutic regimens containing anthracycline. Recent studies, however, have identified that L-asparaginase-containing regimens, such as SMILE (steroid, methotrexate, ifosfamide, L-asparaginase and etoposide), are effective for ENKL. Considering the myelotoxicity of SMILE, its use in the treatment of ANKL needs some modifications, but this treatment scheme is promising in improving the prognosis of NK-cell lymphomas.

Nasal Natural Killer/T-cell Lymphoma with Skin, Eye, and Peroneal Nerve Involvement

Nasal-type natural killer (NK)/T-cell lymphoma (NKTL) is a rare disease strongly associated with Epstein-Barr virus and is often localized to the upper aerodigestive tract at presentation. Extranodal NKTL may involve any extranodal site and disease beyond the nasal cavity is highly aggressive, with short survival time and poor response to therapy. Herein we present a 57-year-old male that had been treated with systemic chemotherapy and cranial radiotherapy for nasaltype NKTL in the palate with skin, right eye, and right peroneal nerve involvement. He was given salvage chemotherapy consisting of 3 cycles of ICE and his response to the therapy was satisfactory, except for persistent right drop foot. About 6 weeks later, the patient presented with bilateral total loss of vision and proptosis; therefore, DHAP chemotherapy was started. Unfortunately, after 1 cycle of the second salvage chemotherapy, he died due to severe fungal infection of the hard palate.

Despite the fact that involvement of any extranodal site is possible, concurrent involvement of many systems in NKTL patients is unusual. Nasal-type NKTL has a poor prognosis, despite local radiotherapy and systemic chemotherapy. Physicians should be aware of this rare disorder than can only be diagnosed after extensive immunohistochemical studies.

Conflict of interest:None declared.

Genetic alterations in systemic nodal and extranodal non-cutaneous lymphomas derived from mature T cells and natural killer cells

Mature (peripheral) T-cell and natural killer (NK)-cell lymphomas comprise a series of rather different neoplasms. Based on morphologic, immunophenotypic, genetic, and clinical data, the World Health Organization classification recognizes more than 20 entities or provisional entities. The variable clinical presentations, the objective recognition and pathological stratification, the difficulties regarding treatment, and the hardly predictable response to therapy indicate that the management of these entities requires novel tools. In contrast to B-cell lymphomas or precursor T-cell neoplasms, few recurrent translocations have been identified so far in T-cell non-Hodgkin's and NK-cell lymphomas. Additionally, some of the entities recognized by the World Health Organization classification are very rare and very scarce molecular data are available for T-cell lymphomas. Here, we have reviewed published reports focusing on the genetic lesions and gene expression profiling underlying systemic nodal and extranodal non-cutaneous mature T-cell and NK-cell lymphomas. We also provide a summary of new agents in clinical development and outline some future directions.

Lymphomatoidgastropathy mimicking extranodal NK/T cell lymphoma, nasal type: A case report

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, exhibits aggressive tumor behavior and carries a poor prognosis. Recently, lymphomatoid gastropathy with NK/T cell infiltration into gastric mucosa has been recognized as a pseudo-malignant disease which regresses without treatment. Because the conventional immunohistochemical criteria of lymphomatoid gastropathy is similar to that of extranodal NK/T-cell lymphoma nasal type, it is difficult to distinguish between the two conditions by histopathological evaluation only. Here, we report a rare case of lymphomatoid gastropathy in a 57-year-old female. Gastroendoscopy on routine check-up revealed elevated reddish lesions < 1 cm in diameter in the gastric fornix and body. Although repeat endoscopies at 1 and 6 mo later revealed no gastric lesions at any locations without any treatments, at 12 mo later gastric lymphomatoid lesions recurred at gastric fornix and body. Histological examination of endoscopic biopsy specimens at 12 mo showed atypical NK cell infiltration with CD3⁺, CD4^-, CD5^-, CD7⁺, CD8^-, CD20^-, CD30^-, CD56⁺, CD79a^- and T-cell-restricted intracellular antigen-1⁺ into gastric mucosa. After treatment for Helicobacter pylori (H. pylori) eradication, the lesions disappeared in all locations of the gastric fornix and body over the subsequent 12 mo. Here, we report a case of H. pylori-positive lymphomatoid gastropathy with massive NK-cell proliferation, and also review the literature concerning newly identified lymphomatoid gastropathy based on comparison of extra nodal NK/T-cell lymphoma nasal type. In any case, these lesions are evaluated with biopsy specimens, the possibility of this benign entity should be considered, and excessive treatment should be carefully avoided. Close follow-up for this case of lymphomatoid gastropathy is necessary to exclude any underlying malignancy.

Prospective measurement of Epstein-Barr virus-DNA in plasma and peripheral blood mononuclear cells of extranodal NK/T-cell lymphoma, nasal type

Epstein-Barr virus (EBV)-DNA was prospectively analyzed in plasma and mononuclear cells (MNCs) from peripheral blood in patients with extranodal natural killer (NK)/T-cell lymphoma, nasal type, to evaluate the clinical significance for diagnosis, monitoring the tumor burden, and prognostication. Thirty-three patients were enrolled, and 32 were evaluable. Pretreatment plasma and MNC EBV-DNA was detectable in 14 (range, 50-71 000 copies/mL) and 6 patients (range, 20-780 copies/μg DNA), respectively, and both were well correlated (r = 0.8741, P < .0001). Detectable plasma EBV-DNA was associated with higher clinical stage (P = .02), presence of B symptoms (P = .02), worse performance status (P = .02), and higher serum soluble IL-2 receptor level (P < .0001). Twenty-two patients attained complete response. Plasma EBV-DNA level was significantly higher in nonresponders than in responders (mean, 16,472 vs 2,645 copies/mL; P = .02). Multivariate analysis showed clinical stage (hazard ratio, 9.0; 95% confidence interval, 1.8%-45.0%) and pretreatment plasma EBV-DNA (hazard ratio, 10.6; 95% confidence interval, 1.3%-87.0%) were significant prognostic factors. Three-year overall survival of plasma EBV-DNA positive and negative patients was 42.9% and 94.4%, respectively (P = .0009). Plasma was a preferable sample for this purpose in NK/T-cell lymphoma, nasal type, and EBV-DNA level was a good indicator for response and overall survival.

The role of natural killer cells in autoimmune blistering diseases

The major focus of this paper is to describe and evaluate current information on the role of natural killer cells (NK cells) in the pathogenesis of blistering diseases. Until now, only pemphigus vulgaris (PV) has been studied. One co-culture study demonstrated that CD4+ T cells from the peripheral blood or perilesional skin of patients with active disease proliferate and secrete cytokines in the presence of major histocompatibility class II-expressing NK cells loaded with antigenic desmoglein self-peptides. Another study showed that NK cells can contribute to a T helper type 2-biased immune response through impaired interleukins (IL)-12 signaling and upregulation of IL, IL-10 and IL-5. Although significant data on other blistering diseases are unavailable at present, some studies implicate NK cells in disease progression. For instance, information on the role of NK cells in psoriasis and their production of tumor necrosis factor-α (TNF-α) will be provided since several TNF-α-inhibitors are used in its treatment. Studies on alopecia areata are also included in this paper because NK cells seem to play a key role in its pathogenesis. This review highlights the potential importance of NK cells and NKT cells as members of the large repertoire of cells and soluble mediators that play a critical role in pathogenesis of blistering diseases and other autoimmune diseases involving the skin. Therefore, the authors advocate a greater focus and interest on the study of the interaction of NK cells and the skin.

Aberrant antigenic expression in extranodal NK/T-cell lymphoma: a multi-parameter study from Thailand

Background

Extranodal NK/T-cell lymphoma, nasal type (ENKTL) is not common worldwide, but it is the most common T- and NK-cell lymphomas in many Asian countries. Immunophenotypic profiles were studied based on limited series. The authors, therefore, studied on ENKTL according to characterize immunophenotypic profiles as well as the distribution of EBV subtype and LMP-1 gene deletion.

Methods

By using tissue microarray (TMA), immunohistochemical study and EBV encoded RNA (EBER) in situ hybridization were performed. T-cell receptor (TCR) gene rearrangement, EBV subtyping, and LMP-1 gene deletion were studied on the available cases.

Results

There were 22 cases eligible for TMA. ENKTL were positive for CD3 (91%), CD5 (9%), CD7 (32%), CD4 (14%), CD56 (82%), TIA-1 (100%), granzyme B (95%), perforin (86%), CD45 (83%), CD30 (75%), Oct2 (25%), and IRF4/MUM1 (33%). None of them was positive for βF1, CD8, or CD57. TCR gene rearrangement was negative in all 18 tested cases. EBV was subtype A in all 15 tested cases, with 87% deleted LMP-1 gene. Cases lacking perforin expression demonstrated a significantly poorer survival outcome (p = 0.008).

Conclusions

The present study demonstrated TIA-1 and EBER as the two most sensitive markers. There were a few CD3 and/or CD56 negative cases noted. Interestingly, losses of CD45 and/or CD7 were not uncommon while Oct2 and IRF4/MUM1 could be positive in a subset of cases. Based on the present study in conjunction with the literature review, determination of PCR-based TCR gene rearrangement analysis might not be a useful technique for making diagnosis of ENKTL.

Extranodal natural killer/T cell lymphoma, nasal type presenting as a palatal perforation and naso-oral fistula

Extranodal natural killer/T cell lymphoma (ENKL), nasal type, a rare disease presenting with vague non-specific symptoms, can impose great diagnostic difficulties and may masquerade several infectious, rheumatological or neoplastic conditions. Here, the authors report a case of ENKL presenting as a palatal perforation, naso-oral fistula and fever in a 21-year-old man, which was initially misdiagnosed as bacterial osteomyelitis, invasive fungal infection and Wegener's granulomatosis. The case report underlines the possibility of ENKL occurring at a young age, its rapidly progressive and locally destructive nature, associated diagnostic challenges and the importance of immunophenotyping in establishing the diagnosis.

Epstein-barr virus-positive diffuse large B-cell lymphoma of the elderly: what we know so far

Epstein-Barr virus-positive (EBV-positive) diffuse large B-cell lymphoma (DLBCL) of the elderly is a newly described lymphoproliferative disorder recently included as a "provisional" entity in the most current WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. The objective of this review is to provide a thorough and current summary of the existing knowledge of this subtype of DLBCL. We will review and discuss the incidence of EBV expression in DLBCL, the pathogenesis behind EBV-driven malignant transformation of B cells, the different EBV latency patterns associated with DLBCL, the distinct pathologic characteristics of EBV-positive DLBCL, the potential predictive and prognostic value of EBV tumoral status in patients with DLBCL, and potential strategies for the treatment of this rare entity, which is characterized by a suboptimal response to therapy and poor survival rate.

Primary small intestinal natural killer/T cell lymphoma mimicking tuberculous peritonitis: report of a case and review of the literature

Extranodal natural killer/T cell lymphoma is very rarely encountered in clinical practice. It has a high mortality rate and very short median survival. Early diagnosis of these rare tumors, especially those originating from the small intestine, is usually difficult because of its nonspecific symptoms. Herein, we describe a case of a primary small intestinal natural killer/T cell lymphoma in a 52-year-old man who presented with abdominal fullness and weight loss. The clinical symptoms, elevation of serum levels of cancer antigen-125, and presence of ascites initially led to the suspicion of tuberculous peritonitis. Abdominal computed tomography scan demonstrated a hypodense tumor in the jejunum. Finally, the tumor was surgically confirmed to be a natural killer/T-cell lymphoma. Although aggressive chemotherapy was prescribed, the patient subsequently died of disease progression. In addition, we also review the English literature on this rare disease.

Treatment of advanced extranodal NK/T cell lymphoma, nasal-type and aggressive NK-cell leukemia

Extranodal NK/T cell lymphoma, nasal type (ENKL) with advanced stage and aggressive NK-cell leukemia (ANKL) are highly aggressive neoplasms with a dismal clinical outcome. It is well known that P-glycoprotein, which is a product of MDR1 gene and related to multi-drug resistance, is expressed on tumor cells of ENKL or ANKL. This is a major reason for the refractoriness to conventional chemotherapeutic regimens for malignant lymphoma containing anthracycline. However, recent studies have identified that several drugs including L: -asparaginase, methotrexate and alkylators show excellent effect for these tumors. The SMILE (steroid, methotrexate, ifosfamide, L: -asparaginase and etoposide) regimen is one of the promising regimens for advanced or relapsed/refractory ENKL, but its myelotoxicity is strong. ANKL needs another treatment strategy because of a systemic disease progression and extensive organ insufficiency. Optimal treatment scheme using such effective agents for these unfavorable NK-cell tumors should further be explored.

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.

Lymphomatoid gastropathy: a distinct clinicopathologic entity of self-limited pseudomalignant NK-cell proliferation

Diagnostic errors in distinguishing between malignant and reactive processes can cause serious clinical consequences. We report 10 cases of unrecognized self-limited natural killer-cell proliferation in the stomach, designated as lymphomatoid gastropathy (LyGa). This study included 5 men and 5 women (age, 46-75 years) without any gastric symptoms. Gastroscopy showed elevated lesion(s) (diameter, ∼ 1 cm). Histologically, medium-sized to large atypical cells diffusely infiltrated the lamina propria and, occasionally, the glandular epithelium. The cells were CD2(+/-), sCD3(-), cCD3(+), CD4(-), CD5(-), CD7(+), CD8(-), CD16(-), CD20(-), CD45(+), CD56(+), CD117(-), CD158a(-), CD161(-), T cell-restricted intracellular antigen-1(+), granzyme B(+), perforin(+), Epstein-Barr early RNA(-), T-cell receptor αβ(-), and T-cell receptor γδ(-). Analysis of the 16 specimens biopsied from 10 patients led to a diagnosis of lymphoma or suspected lymphoma in 11 specimens, gastritis for 1 specimen, adenocarcinoma for 1 specimen, and LyGa or suspected LyGa for 3 specimens. Most lesions underwent self-regression. Three cases relapsed, but none of the patients died. According to conventional histopathologic criteria, LyGa is probably diagnosed as lymphoma, especially as extranodal natural killer/T-cell lymphoma, nasal type. However, LyGa is recognized as a pseudomalignant process because of its clinical characteristics. The concept of LyGa should be well recognized.

Malignant lymphoma of the head and neck

Malignant lymphomas represent approximately 5% of all malignant neoplasms of the head and neck area. They are classically divided into two subgroups, Hodgkin's lymphomas (HLs) and non-Hodgkin's lymphomas (NHLs). We describe the clinical characteristics of head and neck lymphomas and the methods to establish the diagnosis. The World Health Organization classification of lymphoid tissues describes more than 50 different histological types, and we analyse the most common staging system for lymphomas, the Ann Arbor staging system. Finally, the different therapeutic approaches are discussed.

Extra-nodal natural killer/T cell lymphoma, nasal-type, treated by concurrent chemoradiotherapy

The present study reports on a case of extra-nodal natural killer/T cell lymphoma, nasal-type (ENKL), stage IIEA, in a 50-year-old woman who presented with a white tumor on a refractory ulcer on the gum. Concurrent chemoradiotherapy was administered, and effected a partial response. However, tumor recurrence was observed 5 months after the final diagnosis, and the patient succumbed 1 month after recurrence. Although a definitive treatment for ENKL has yet to be established due to its rarity, radiation therapy (RT) is crucial to therapy, as ENKL is very sensitive to RT. However, treatment with radiation levels above 50 Gy with an extended RT field are required for a favorable outcome. The development of novel chemotherapy regimens may therefore be useful. Additionally, autologous or allogenic hematopoietic stem-cell transplantation may prove to be a promising approach.