Nation-wide study of lethal mid-line granuloma in Japan: frequencies of wegener's granulomatosis, polymorphic reticulosis, malignant lymphoma and other related conditions

NK-/T-cell lymphomas

Natural killer/T-cell lymphoma (NKTL) is a sub-type of Epstein-Barr virus (EBV)-related non-Hodgkin lymphomas common in Asia and Latin America but rare elsewhere. Its pathogenesis is complex and incompletely understood. Lymphoma cells are transformed from NK- or T-cells, sometimes both. EBV-infection and subsequent genetic alterations in infected cells are central to NKTL development. Hemophagocytic syndrome is a common complication. Accurate staging is important to predict outcomes but there is controversy which system is best. More than two-thirds of NKTL lympohmas are localized at diagnosis, are frequently treated with radiation therapy only and have 5-year survival of about 70 percent. Persons with advanced NKTLs receive radiation therapy synchronously or metachronously with diverse multi-drug chemotherapy typically including L-asparginase with 5-year survival of about 40 percent. Some persons with widespread NKTL receive chemotherapy only. There are few data on safety and efficacy of high-dose therapy and a haematopoietic cell autotransplant. Immune therapies, histone deacetylase (HDAC)-inhibitors and other drugs are in early clinical trials. There are few randomized controlled clinical trials in NKTLs and no therapy strategy is clearly best; more effective therapy(ies) are needed. Some consensus recommendations are not convincingly evidence-based. Mechanisms of multi-drug resistance are considered. We discuss these issues including recent advances in our understanding of and therapy of NKTLs.

Extranodal NK/T-Cell Lymphoma, Nasal Type: Genetic, Biologic, and Clinical Aspects with a Central Focus on Epstein-Barr Virus Relation

Extranodal NK/T-Cell Lymphoma, nasal type (ENKTL-NT) has some salient aspects. The lymphoma is commonly seen in Eastern Asia, has progressive necrotic lesions in the nasal cavity, makes midfacial destructive lesions, and shows poor prognosis. The lymphoma cell is originated from either NK- or γδ T-cells, which express CD56. Since the authors first demonstrated the existence of Epstein–Barr virus (EBV) DNA and EBV oncogenic proteins in lymphoma cells, ENKTL-NT has been recognized as an EBV-associated malignancy. Because the angiocentric and polymorphous lymphoma cells are mixed with inflammatory cells on a necrotic background, the diagnosis of ENKTL-NT requires CD56 immunostaining and EBER in situ hybridization. In addition, serum the EBV DNA level is useful for the diagnosis and monitoring of ENKTL-NT. Although ENKTL-NT is refractory lymphoma, the prognosis is improved by the development of therapies such as concomitant chemoradiotherapy. The basic research reveals that a wide variety of intracellular/cell surface molecules, cytokines, chemokines, and micro RNAs are involved in lymphomagenesis, and some of them are related to EBV. Understanding lymphoma behavior introduces new therapeutic strategies, such as the usage of immune checkpoint inhibitors, peptide vaccines, and molecular targeting therapy. This review addresses recent advances in basic and clinical aspects of ENKTL-NT, especially its relation to EBV features.

[Clinical characteristics and prognostic analysis of advanced-stage extranodal NK/T cell lymphoma]

Objective: This study aimed to explore the clinical characteristics, survival rate, and prognostic factors of advanced-stage extranodal nasal type NK/T cell lymphoma (ENKTL) patients. Methods: The clinical data of 51 advanced-stage ENKTL patients in Peking Union Medical College Hospital from January 2012 to September 2019 were retrospectively analyzed. The clinical characteristics, treatment responses, survival rate, and prognostic factors were elucidated. The differences between nasal and non-nasal type and the significance of EBV-DNA in treatment response assessment and prognosis analysis were also evaluated. Results: The male-to-female ratio in the whole group was 2.9∶1 with a median age of 42 years old (range, 14-67 years) . The median follow-up time was 30 months (range, 1-78 months) . The one- and three-year progression-free survival (PFS) rates for the whole cohort were 34.1% and 24.6%, respectively, and the one- and three-year overall survival (OS) rates were 39.9% and 26.6%, respectively. The ratio of nasal to non-nasal type was 1.6∶1. The proportion of hemophagocytic lymphohistiocytosis (HLH) was significantly higher in non-nasal-type patients than nasal-type (P=0.039) , and the complete response (CR) rate of first-line chemotherapy is significantly lower in non-nasal type patients (P=0.008) . The median OS for nasal and non-nasal types were nine months and four months, respectively. The three-year PFS rates of nasal and non-nasal type patients were 36.0% and 10.0% (P=0.029) , respectively, and the three-year OS rates were 37.9% and 11.4% (P=0.050) , respectively. The correlation between the Epstein-Barr virus DNA (EBV-DNA) and treatment response were satisfactory. Survival curve between baseline EBV-DNA-negative and EBV-DNA-positive patients showed no significant difference. The three-year OS rates of EBV-DNA-negative and EBV-DNA-positive patients after one cycle of treatment were 77.9% and 8.1% (P=0.002) , respectively. In a multivariate analysis, EBV-DNA-positive following one cycle of treatment was an independent adverse prognostic factor for OS. Conclusions: The efficacy of pegaspargase-based chemotherapy and long-term survival of advanced-stage ENKTL patients were still poor. Clinical characteristics, treatment response, and long-term survival of non-nasal-type patients were worse than that of nasal-type patients. In a multivariate analysis, EBV-DNA-positive after one cycle of treatment was an independent adverse prognostic factor for OS. It can be used for early prediction of treatment response and prognosis.

Genome-Wide Analysis of Epstein-Barr Virus Isolated from Extranodal NK/T-Cell Lymphoma, Nasal Type

BACKGROUND

Extranodal natural killer (NK) cell/T-cell lymphoma (NKTCL), a rare type of non-Hodgkin's lymphoma, has strongly been associated with Epstein-Barr virus (EBV) infection. However, there are no EBV genomes isolated from NKTCL, and the roles the variations of EBV strains play in the pathogenesis of NKTCL are still unclear.

MATERIALS AND METHODS

In this study, whole EBV genomes from eight primary NKTCL biopsy specimens were obtained using next-generation sequencing, designated NKTCL-EBV1 to NKTCL-EBV8.

RESULTS

Compared with the six mostly referenced EBV strains, NKTCL-EBVs closely resemble the GD1 strain but still harbor 2,072 variations, including 1,938 substitutions, 58 insertions, and 76 deletions. The majority of nonsynonymous mutations were located in latent and tegument genes. Moreover, the results from phylogenetic analysis of whole NKTCL genomes and specific genes demonstrated that all the NKTCL-EBVs were related to Asian EBV strains. Based on the amino acid changes in certain residues of latent membrane protein 1 (LMP1) and EBV-determined nuclear antigen 1 (EBNA1), all the NKTCL-EBVs were sorted to China 1 and V-val subtype, respectively. Furthermore, changes in CD4+ and CD8+ T-cell epitopes of EBNA1 and LMP1 may affect the efficacy for a cytotoxic T lymphocyte (CTL)-based therapy.

CONCLUSION

This is the first large study to our knowledge to obtain EBV genomes isolated from NKTCL and show the diversity of EBV genomes in a whole genome level by phylogenetic analysis.

IMPLICATIONS FOR PRACTICE

In this study, the full-length sequence of Epstein-Barr virus (EBV) isolated from eight patients with nasal natural killer/T-cell lymphoma (NKTCL) was determined and further compared with the sequences previously reported isolated from other malignancies. Phylogenetic analysis showed that NKTCL-EBV strains are close to other Asian subtypes instead of non-Asian ones, leading to the conclusion that EBV infections are more likely affected by different geographic regions rather than particular EBV-associated malignancies. Therefore, these data have implications for the development of effective prophylactic and therapeutic vaccine approaches targeting the personalized or geographic-specific EBV antigens in these aggressive diseases.

Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type: Basic Science and Clinical Progress

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (NNKTL) has very unique epidemiological, etiologic, histologic, and clinical characteristics. It is commonly observed in Eastern Asia, but quite rare in the United States and Europe. The progressive necrotic lesions mainly in the nasal cavity, poor prognosis caused by rapid local progression with distant metastases, and angiocentric and polymorphous lymphoreticular infiltrates are the main clinical and histologic features. Phenotypic and genotypic studies revealed that the lymphoma is originated from either NK- or γδ T-cell, both of which express CD56. In 1990, the authors first reported the presence of Epstein-Barr virus (EBV)-DNA and EBV-oncogenic proteins, and EBV has now been recognized to play an etiological role in NNKTL. in vitro studies revealed that a wide variety of cytokines, chemokines, and micro RNAs, which may be produced by EBV-oncogenic proteins in the lymphoma cells, play important roles for tumor progression in NNKTL, and could be therapeutic targets. In addition, it was revealed that the interaction between NNKTL cells and immune cells such as monocytes and macrophages in NNKTL tissues contribute to lymphoma progression. For diagnosis, monitoring the clinical course and predicting prognosis, the measurements of EBV-DNAs and EBV-micro RNAs in sera are very useful. For treatment with early stage, novel concomitant chemoradiotherapy such as DeVIC regimen with local radiotherapy and MPVIC-P regimen using intra-arterial infusion developed with concomitant radiotherapy and the prognosis became noticeably better. However, the prognosis of patients with advanced stage was still poor. Establishment of novel treatments such as the usage of immune checkpoint inhibitor or peptide vaccine with molecular targeting therapy will be necessary. This review addresses recent advances in the molecular understanding of NNKTL to establish novel treatments, in addition to the epidemiologic, clinical, pathological, and EBV features.

Epstein-Barr Virus-Associated T and NK-Cell Lymphoproliferative Diseases

EBV-associated T and NK-cell lymphoproliferative diseases (EBV-T/NK LPDs) are characterized by the transformation and proliferation of EBV-infected T or NK cells. The 2016 revised World Health Organization classification recognizes the following EBV-positive lymphoproliferative disorders (LPD): chronic active EBV infection (CAEBV) of T- and NK-cell type (cutaneous and systemic forms), systemic EBV-positive T-cell lymphoma of childhood, aggressive NK-cell leukemia, extranodal NK/T-cell lymphoma, nasal type, and the new provisional entity primary EBV-positive nodal T/NK-cell lymphoma. EBV-associated hemophagocytic lymphohistiocytosis (HLH), although not included in the WHO classification because it is a reactive, inflammatory disease, is included in this review because it can be life-threatening and may have overlapping features with other EBV+ T/NK LPDs. EBV+ T/NK LPDs are rare diseases difficult to diagnose and manage properly, because some LPDs have unusual presentations, and discrepancies between clinical and histological findings might be encountered. Furthermore, EBV+ T/NK disorders share some clinico-pathological features, and may evolve into other categories during the clinical course, including malignant transformation of CAEBV. Here, we review the EBV+ T/NK LPDs in terms of their definitions, clinical features, histology, immunophenotype, molecular findings, and pathogenesis. This review aims to increase our understanding and awareness of the differential diagnosis among the different EBV+ T/NK LPDs. New insights into the genetic characteristics of these disorders will also be discussed.

Asparagine synthetase expression and its potential prognostic value in patients with NK/T cell lymphoma

Natural killer (NK)/T cell lymphoma usually shows a highly aggressive clinical course and the overall prognosis is poor. At present, there are no standard therapeutic regimens for this disease. Although chemotherapeutic protocols containing L-asparaginase (L-Asp) or pegaspargase (PEG‑Asp) have improved the efficacy of treatment, some patients are resistant to L-Asp or PEG-Asp. Previous studies demonstrated that the elevated expression of asparagine synthetase (ASNS) is correlated with the resistance to L-Asp or PEG-Asp and may also affect the prognosis in some types of tumors, but the expression level and clinical significance of ASNS in NK/T cell lymphoma remain unknown. Therefore, we investigated the expression and clinical significance of ASNS in lymphoma cell lines and patients with NK/T cell lymphoma. Firstly, we detected PEG-Asp and L-Asp activity using MTT assay and expression of ASNS using real-time PCR in the 7 lymphoma cell lines. Secondly, we used branched DNA-liquidchip technology (bDNA-LCT) for detecting ASNS mRNA in formalin-fixed, paraffin-embedded tissue sections in 50 cases of NK/T cell lymphoma and in 12 cases of nasal polyps and chronic rhinitis. Moreover, we analyzed the correlations between the expression of ASNS and the sensitivity to L-Asp and PEG-Asp in 7 lymphoma cell lines and with clinicopathological features and prognosis of NK/T cell lymphoma patients who used chemotherapy containing L-Asp and PEG-Asp. There was a marked difference in the sensitivity to L-Asp and PEG-Asp of the 7 lymphoma cell lines. YTS and SNK-6 cells were highly sensitive to PEG-Asp and had relatively low levels of ASNS mRNA expression. Hut-78, Jurkat and Karpas 299 cells were naturally resistant to PEG-Asp, and the ASNS expression levels were extremely high. The expression level of ASNS was relatively low in the NK/T cell lymphoma tissue compared to levels in the nasal polyps and chronic rhinitis (0.480±0.307 vs. 0.739±0.267; P=0.009). ASNS expression level was associated with III-IV tumor stage (P=0.041) and a high International Prognostic Index (P=0.018) in patients with NK/T cell lymphoma. The NK/T cell lymphoma patients with higher ASNS expression had a reduced median survival time when compared with the survival of patients with low ASNS expression (P=0.033). Cox regression test showed that the ASNS expression level is an independent prognostic factor for NK/T cell lymphoma patients. In conclusion, the expression of ASNS was closely related with the sensitivity of lymphoma cell lines to L-Asp and PEG-Asp in vitro and also had a certain effect on the survival of NK/T cell lymphoma patients. In conclusion, high ASNS expression in NK/T cell lymphoma is correlated with worse clinicopathological features.

Characteristics and prognostic factors for head and neck non-Hodgkin's lymphoma in Chinese patients

BACKGROUND AND OBJECTIVES

The head and neck region is the second most frequent anatomical site of extranodal lymphomas. These tumours affect many individuals worldwide, justifying epidemiological studies in different countries. This study evaluated the characteristics, treatments and prognostic factors for non-Hodgkin's lymphoma of the head and neck in Chinese patients.

METHOD

The clinical manifestations, clinicopathological characteristics, multidisciplinary treatment and prognostic factors for 102 patients with extranodal non-Hodgkin's lymphoma of the head and neck were analysed retrospectively.

RESULT

The tonsil was the most commonly involved primary site, followed by the nasal cavity. The most common histological subtype was diffuse large B-cell lymphoma, followed by natural killer T-cell lymphoma. Patients receiving a combination of rituximab and chemotherapy did better than those receiving chemotherapy alone. Prognosis was significantly associated with both International Prognostic Index and histological subtype; the former was especially strongly associated with poor survival.

CONCLUSION

In this group of Chinese patients, diffuse large B-cell lymphoma was the most common pathological subtype, but the incidence of T-cell lymphomas was higher than that reported in the USA. Combined rituximab and chemotherapy led to better outcomes than chemotherapy alone. Prognosis depended on both International Prognostic Index and histological subtype.

p63 and p53 expression in extranodal NK/T cell lymphoma, nasal type

OBJECTIVES

To investigate the pathological and clinical meaning of p63 in extranodal nasal type NK/T cell lymphoma (NKTCL).

METHODS

We detected p63 and p53 expression using immunohistochemistry staining in 84 cases of NKTCL from Southern of China, an area with a well known high incidence of nasopharyngeal carcinoma, which is closely associated with Epstein-Barr virus infection. Moreover, we analysed the relationship between p63 and p53 expression and the clinicopathological features of NKTCL.

RESULTS

Our results first showed that p63 expression was found in 14.3% (12/84) of NKTCL compared with 6.6% (2/30) in reactive lymphoid hyperplasia of nasopharynx. p63 Expression rate in NKTCL was significantly higher than that in reactive lymphoid hyperplasia of nasopharynx (p=0.016). NKTCL patients with p63 positivity had poorer 5-year overall survival rate (29.2%) than that (49.9%) of p63 negativity. p53 expression was found in 33.3% (28/84) of NKTCL. Our data showed that p53 expression was significantly associated with tumour stage (p=0.016) and international prognostic index (p=0.026) in patients with NKTCL. Cox regression test showed that p53 expression rate and international prognostic index score were statistically independent prognostic factors for NKTCL patients (p=0.002 and p=0.016, respectively). Our results suggest that p63 and p53 might play a role in pathogenesis of NKTCL.

Activity and damage in granulomatosis with polyangiitis

AIM

To retrospectively analyze disease activity and damage-associated factors in granulomatosis with polyangiitis (GPA) in Turkey.

METHOD

A retrospective analysis was carried out in 21 GPA patients. Assessments for activity were performed with the Birmingham Vasculitis Activity Score for GPA (BVAS/GPA) and for permanent organ damage by the Vasculitis Damage Index (VDI).

RESULTS

Lower BVAS/GPA (P = 0.002), absence of renal involvement (P = 0.003) and higher creatinine clearence (P = 0.000) at diagnosis increased the likelihood of achieving remission at 6 weeks. Relapses were associated with high creatinine clearence (P = 0.021), low BVAS/GPA (P = 0.014), absence of renal involvement (P = 0.036) and proteinuria (< 0.5/24 h) (P = 0.013) at diagnosis, whereas achieving remission at 6 weeks (P = 0.012) was associated with absence of co-trimoxazole usage (P = 0.038) and less severe clinical subgroup (P = 0.034). Lower cumulative first 6 months of cyclophosphamide and methylprednisolone were associated with earlier (≤ 12 months) relapses (P = 0.048 and P = 0.083, respectively). Baseline damage (VDI ≥ 1) was associated with a delay in diagnosis (P = 0.032), presentation with milder clinical subgroups (P = 0.052) and low serum creatinine (P = 0.013). The increase in VDI in the first 12 months (early damage) constituted most (91%) of the total damage measured at the end of follow-up.

CONCLUSIONS

Despite high early remission rates, relapse represents a major problem in localized GPA in our study. Baseline damage was associated with longer diagnostic delay and lower baseline serum creatinine. The initial phase of the disease seems to be the most crucial period for mortality and accumulated damage.

Predictive value of pretreatment positron emission tomography/computed tomography in patients with newly diagnosed extranodal natural killer/T-cell lymphoma

The role of (18)Fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) in extranodal natural killer/T-cell lymphoma (ENKL) is not well established. This study aimed to investigate the prognostic role of the pretreatment maximum standardized uptake value (SUV(max)) on PET/CT in patients with newly diagnosed ENKL. Among 364 consecutive patients with newly diagnosed ENKL, 81 patients were included and reviewed. The impact of SUV(max) on survival and the relationship between SUV(max) and other clinicopathological parameters were analyzed. The median SUV(max) was 14.6 (range 2.0-45.4). The optimal cutoff value of SUV(max) to predict overall survival (OS) was 15. Patients with high SUV(max) (SUVmax >15) were associated with bulky disease (P < 0.001), local invasion (P = 0.030), high score of Korean Prognostic Index (KPI, P = 0.046), resistance to primary treatment (P = 0.014), poor OS (P < 0.001), and unfavorable progression-free survival (P < 0.001). With a median follow-up of 25.0 months, the median OS was 63.0 months (range 2.0-99.0 months). Multivariate analyses revealed the following independent prognostic factors for OS: age >60 years (P = 0.001), stage III-IV (P = 0.023), SUV(max) >15 (P = 0.020), and bulky disease (>5 cm) (P = 0.002). By using the SUV(max), patients in most subgroups stratified by the KPI or the International Prognostic Index (IPI) were further discriminated in OS with significant statistical difference. Our results suggest the pretreatment SUV(max) is predictive of prognosis in patients with newly diagnosed ENKL. The SUV(max) may provide additional prognostic information for IPI and KPI.

Monocytes enhance cell proliferation and LMP1 expression of nasal natural killer/T-cell lymphoma cells by cell contact-dependent interaction through membrane-bound IL-15

Nasal natural killer (NK)/T-cell lymphoma (NNKTL) is an Epstein-Barr virus (EBV)-related malignancy with poor prognosis and has distinct histological features characterized by angiocentric and polymorphous lymphoreticular infiltrates including inflammatory cells such as granulocytes, monocytes, macrophages and lymphocytes. Here, we show that the monocytes enhance proliferation as well as LMP1 expression of NNKTL cells by cell contact-dependent interaction through membrane-bound interleukin (IL)-15. We used two EBV-positive NK-cell lines, SNK6 and KAI3, which originated from two patients-SNK6 from a patient with NNKTL and KAI3 from a patient with a severe mosquito allergy. We cocultured the cell lines with granulocytes or monocytes and examined whether proliferation, survival and LMP1 expression of the cells changed. Although cocultured granulocytes did not affect proliferation, survival or LMP1 expression of the cells, cocultured monocytes enhanced both proliferation and LMP1 expression in a dose-dependent manner. These phenomena were not seen when monocytes were placed in a separate chamber. Moreover, the monocyte-inducible proliferation and LMP1 expression were inhibited by treatment with an antibody against IL-15. Furthermore, production of interferon-gamma-inducible protein (IP)-10 were enhanced by coculture with monocytes and were inhibited by the antibody. Immunohistological studies confirmed that a number of infiltrating CD14-positive monocytes contacted CD56-positive lymphoma cells in all of 20 NNKTL tissues tested. These results suggest that monocytes enhance cell growth as well as LMP1 expression of NNKTL cells by cell contact-dependent interaction through membrane-bound IL-15. In the microenvironment of NNKTL tissue, a positive feedback loop of interaction between lymphoma cells and monocytes may be present and contribute to lymphoma progression.

Absolute lymphocyte count is a novel prognostic indicator in extranodal natural killer/T-cell lymphoma, nasal type

BACKGROUND

extranodal natural killer (NK)/T-cell lymphoma (ENKL) is a heterogeneous entity with poor survival, requiring risk stratification in affected patients. We proposed absolute lymphocyte count (ALC) as a new prognostic factor in ENKL.

PATIENTS AND METHODS

we retrospectively analyzed 128 patients newly diagnosed with ENKL. Independent prognostic factors of survival were determined by Cox regression analysis.

RESULTS

patients with low ALC (<1.0 × 10(9)/l) at diagnosis tended to have more adverse clinical features. Patients with high ALC (≥1.0 × 10(9)/l) at diagnosis had better overall survival (OS; P < 0.0001) and progression-free survival (PFS; P<0.0001), and achieved higher complete remission rates (P=0.001). Multivariate analysis with known prognostic factors showed that ALC, B symptoms and advanced stage were independent predictors for OS and PFS. Using the International Prognostic Index, Prognostic Index for Peripheral T-cell lymphoma unspecified, or Korean Prognostic Index for nasal NK/T-cell lymphoma, the majority of patients were in the low-risk category (with no or one adverse factor). ALC was helpful to differentiate the low-risk patients with different survival outcomes (P < 0.0001).

CONCLUSIONS

our data suggest that ALC at diagnosis is a novel, powerful predictor of prognosis in ENKL. Immune status at diagnosis might have an important influence on survival in patients with ENKL.

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

BACKGROUND

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Expression of the metalloproteases MMP-1, MMP-2, MMP-3, MMP-9, MMP-11, TIMP-1 and TIMP-2 in angiocentric midfacial lymphomas

Background

Extranodal T/NK cell lymphomas possess distinctive clinico-pathological characteristics: they are angiocentric, exhibit extensive necrosis. Prognosis is poor in the short term. The objective is to explore the expression of different MMPs in the cells and stroma which are around of the blood vessels damaged and their correlation with clinico-pathological parameters.

Patients and methods

Twenty cases of this type of lymphomas were studied and collected patient clinical data. The expressions of MMP-1, 2, 3, 9, 11, 13 and TIMP-1, 2 were studied by immunohistochemistry. Ultrastructural studies were performed in two cases. Statistical analysis was done with Fisher's exact test, Chi² test.

Results

Of the 20 patients, 13 were men with median age of 43 years. In 13 patients the primary tumor was localized in the nasal cavity. Treatment was combined chemotherapy and radiotherapy in 60%. The 55% advanced clinical stages, 70% died from the disease. There were neoplastic cell and peritumoral fibroblasts positivity to MMP-1 and MMP-11 in most of the cases. The MMPs-2, 3 and 9 were expressed in neoplastic cell between 30 to 65%of the cases. TIMP-1 was presented mainly in the epithelium and TIMP-2 was poor expressed of the all cases.

Conclusion

There were no statistical significance between the different enzymes used and the clinical parameters, besides status and survival of the patients. It is necessary to study more enzymes and focus them to quantify and determine their activity, in order to have a better correlation with histological features in this type of neoplasm.

Nasal NK/T-cell lymphoma: epidemiology and pathogenesis

Nasal NK/T-cell lymphoma (NKTCL) is an uncommon disease, but usually shows a highly aggressive clinical course. The disease is much more frequent in Asian and Latin American countries than in Western countries, and is universally associated with Epstein–Barr virus (EBV) infection. Analyses of gene mutations, especially p53 and c-KIT, revealed the different frequencies by district. Epidemiological studies revealed the changes of the disease frequency in Korea during the period from 1977–1989 to 1990–1996. Case-control study showed that the exposure to pesticides and chemical solvents could be causative of NKTCL. Further studies including HLA antigen typing of patients is necessary to further clarify the disease mechanism.

The enhanced expression of the matrix metalloproteinase 9 in nasal NK/T-cell lymphoma

Background

Nasal NK/T cell lymphoma is an aggressive disease and has a poor prognosis. Nasal NK/T cell lymphoma is refractory to conventional chemotherapy and has strong tendency of widespread relapse or dissemination into distant sites.

Methods

We immunohistochemically studied nasal NK/T-cell lymphoma to elucidate the unique characteristics of nasal NK/T-cell lymphoma, such as its higher metastatic tendency and its vast necrosis which leads to destruction of the involved tissues. The expression of P-glycoprotein and MMP-9 was evaluated in the 20 patients with nasal NK/T-cell lymphoma and 25 with nasal non-NK/T-cell lymphoma and the relationship between expression of these proteins and clinical results were analyzed in this report.

Results

Overall 5-year survival rates for patients with nasal NK/T cell lymphoma, and nasal non-NK/T cell lymphoma were 51%, and 84%. Distant involvement free 5-year survival rates for patients with nasal NK/T cell lymphoma, and nasal non-NK/T cell lymphoma were 53%, and 79%.

Overall positivity for P-glycoprotein was observed in 10 of 19 patients with NTL and in 13 of 23 patients with non-NTL. When the overall survival rate was compared between patients with P-glycoprotein positive and negative, there was no difference between them.

Sixteen of the 19 patients with nasal NK/T cell lymphoma expressed MMP-9. In contrast, only 8 of the 22 patients with nasal non-NK/T cell lymphoma expressed MMP-9. Distant involvement free 5-year survival rates for patients with MMP-9 negative, and MMP-9 positive were 92%, and 61%, respectively. The difference was statistically significant (p = 0.027).

Conclusion

Positive immunoreactivity for P-glycoprotein was not an independent prognostic factor in nasal NK/T-cell lymphomas, which stresses the importance of exploring other mechanisms of drug resistance. The strong expression of MMP-9 is uniquely characteristic of nasal NK/T cell lymphoma and may contribute to its strong tendency to disseminatate and the extensive necrosis which is always seen. However, our results are based on univariate comparisons, and as such, should be viewed with some caution.

Ki-67 expression is predictive of prognosis in patients with stage I/II extranodal NK/T-cell lymphoma, nasal type

BACKGROUND

Localized extranodal natural killer (NK)/T-cell lymphoma, nasal type, commonly has a low or low-intermediate risk of the international prognostic index (IPI), so the IPI has shown inconsistency in predicting prognosis. Thus, we analyzed Ki-67 expression and proposed a new prognostic model including Ki-67 expression for stage I/II extranodal NK/T-cell lymphoma.

PATIENTS AND METHODS

We studied Ki-67 expression and its relationship with prognosis in 50 patients with extranodal NK/T-cell lymphoma.

RESULTS

The patients were dichotomized by the median value: low (<65%) versus high Ki-67 (> or =65%). High Ki-67 was associated with a worse overall survival (OS; P = 0.021) and disease-free survival (DFS; P = 0.044). In multivariate analysis, Ki-67 expression and primary site of involvement were found to be an independent prognostic factor for OS and DFS (P < 0.05). Based on these results, we proposed a new clinico-pathological prognostic model with Ki-67 expression and the primary site of involvement. It showed a high degree of correlation with worse OS and DFS (P < 0.001).

CONCLUSIONS

Ki-67 expression is predictive of prognosis, and our prognostic model may become a useful tool for predicting prognosis in patients with stage I/II extranodal NK/T-cell lymphoma, nasal type.

Nasal natural killer/T-cell lymphoma and its association with type "i"/XhoI loss strain Epstein-Barr virus in Chile

BACKGROUND

Nasal T/natural killer (NK)-cell lymphoma is an aggressive type of non-Hodking's lymphoma associated with Epstein-Barr virus (EBV) and striking geographical variations worldwide.

AIM

To characterise nasal NK/T-cell lymphoma associated with genotypes of EBV in Chile, a Latin American country, where multiple strains of EBV, including two new recombinant strains, in healthy individuals were recently found.

METHODS

Cases with diagnosis of primary nasal lymphoma were selected for histological and immunohistochemical analysis (CD3, CD3e, CD4, CD8, CD79a, CD56, CD57 and TIA-1) and in-situ hybridisation, serology and genotyping analysis for EBV.

RESULTS

Out of 22 cases, 9 (41%) cases fulfilled the World Health Organization criteria for nasal NK/T-cell lymphoma; of these 7 (78%) cases were positive for EBV. Genotyping analysis revealed 6 cases of type 1 EBV and wildtype F at the BamHI-F region, 4 cases type "i" EBV at the BamHI-W1/I1 region; XhoI wild type was found in 2 and XhoI loss in 4 cases, respectively. Cosegregation analysis of the BamHI-W1/I1 region and XhoI restriction site showed the new recombinant strain type "i"/XhoI loss in 3 cases and type "i"/XhoI wild-type strain in 1 case. Most patients were treated with combined anthracycline-containing regimens. Half of the cases attained complete remission.

CONCLUSION

Although nasal NK/T-cell lymphomas from Chile share similar clinicopathological features, high association with EBV and unfavourable prognosis with those described elsewhere, genotype analysis shows that the new recombinant type "i"/XhoI loss strain might contribute to explain the intermediate incidence of nasal NK/T-cell lymphomas in Latin America.

Extranodal Natural Killer T-Cell Lymphoma, Nasal-Type: A Prognostic Model From a Retrospective Multicenter Study

Purpose

Patients with natural killer T (NK/T) -cell lymphomas have poor survival outcome, and for this condition there is no optimal therapy. The purpose of this study was to design a prognostic model specifically for extranodal NK/T-cell lymphoma, which can identify high-risk patients who need more aggressive therapy.

Patients and Methods

This multicenter retrospective study was comprised of 262 patients who were diagnosed with NK/T-cell lymphoma.

Results

After a median follow-up duration of 51.2 months, 5-year overall survival rate in 262 patients was 49.5%. Prognostic factors for survival were “B” symptoms (P = .0003; relative risk, 2.202; 95% CI, 1.446 to 3.353), stage (P = .0006; relative risk, 2.366; 95% CI, 1.462 to 3.828), lactate dehydrogenase (LDH) level (P = .0005; relative risk, 2.278; 95% CI, 1.442 to 3.598), and regional lymph nodes (P = .0044; relative risk, 1.546; 95% CI, 1.009 to 2.367). Of 262 patients, 219 had complete information on four parameters. We identified four different risk groups: group 1, no adverse factor; group 2, one factor; group 3, two factors; and group 4, three or four factors. The new model showed a superior prognostic discrimination as compared with the International Prognostic Index (IPI). Notably, the distribution of patients was balanced when a new model was adopted (group 1, 27%; group 2, 31%; group 3, 20%; group 4, 22%), whereas 81% of patients were categorized as low or low-intermediate risks using IPI.

Conclusion

The newly proposed model for extranodal NK/T-cell lymphoma demonstrated a more balanced distribution of patients into four groups with better prognostic discrimination as compared with the IPI.

Expression of interleukin-9 in nasal natural killer/T-cell lymphoma cell lines and patients

PURPOSE

Nasal natural killer (NK)/T-cell lymphoma is associated with EBV and has distinct clinical and histologic features. However, little is known about its genetic features. In this study, we examined the genes expressed by SNK-6 and SNT-8 cells, which were established from nasal NK/T-cell lymphomas, and found that interleukin (IL)-9 was specifically expressed in these two cell lines.

EXPERIMENTAL DESIGN

cDNA array was used to examine the genes expressed by SNK-6 and SNT-8 cells. Expression of IL-9 and IL-9 receptor was investigated by reverse transcription-PCR, ELISA, and flow cytometry. Cell growth was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Immunohistologic staining and ELISA were used to examine IL-9 expression in biopsies and sera from patients, respectively.

RESULTS

In cDNA array, expression of IL-9 mRNA was much higher in SNK-6 and SNT-8 cells than in NK-92 cells from non-nasal NK-cell lymphoma and peripheral blood mononuclear cells from healthy volunteers. Furthermore, IL-9 was specifically expressed by SNK-6 and SNT-8 cells but not by other NK-cell, NK-like T-cell, and T-cell lymphoma/leukemia cell lines. IL-9 receptor was also expressed on the surfaces of SNK-6 and SNT-8 cells. An IL-9-neutralizing antibody inhibited the growth of these two cell lines, whereas recombinant human IL-9 enhanced their growth. Most significantly, IL-9 was present in biopsies and sera from patients with this lymphoma.

CONCLUSIONS

These results suggest that IL-9 plays an important role in nasal NK/T-cell lymphoma possibly via an autocrine mechanism.

How could we make a diagnosis of Wegener's granulomatosis?

Current classification criteria function poorly in diagnosing Wegener's granulomatosis (WG). In this study, we presented a patient with sinonasal symptoms, hematuria, and proteinuria, who had been misdiagnosed as a patient suffering from WG, but finally turned out to be a patient suffering from non-Hodgkin's T cell lymphoma. Diagnostic approach of WG was also discussed.

Life-style and environmental factors in the development of nasal NK/T-cell lymphoma: A case–control study in East Asia

Cases of nasal NK/T-cell lymphoma (NKTCL) occur occasionally in Asian and Latin American countries but rarely in Western countries. The etiological role of life-style and environmental factors in nasal NKTCL was investigated. Five university hospitals in Japan and one each in Korea and China participated in this study; a total of 88 cases and 305 hospital controls were accrued during 2000-2005. The odds ratio (OR) of NKTCL obtained after adjustments of age, sex and country was 4.15 (95% confidence interval (CI), 1.74-9.87) for farmers, 2.81 (CI, 1.49-5.29) for producers of crops, 4.01 (CI, 1.99-8.09) for pesticide users, 11.65 (CI, 1.17-115.82) for residents near garbage burning plants, 2.95 (CI, 1.25-6.95) for former drinkers, and 0.49 (CI, 0.23-1.04) for current smokers. The ORs for crop producers, who minimized their exposure to pesticides by using gloves and glasses, and sprinkling downwind at the time of pesticide use, were 3.30 (95% CI, 1.28-8.54), 1.18 (95% CI, 0.11-12.13) and 2.20 (95% CI, 0.88-5.53), respectively, which were lower than those for producers who did not take these precautions. Exposure to pesticides and chemical solvents could be causative of NKTCL. Taken together, life-style and environmental factors might be risk factors for NKTCL.

Hepatic cytotoxic T-cell infiltrates in patients with peripheral T-cell proliferative diseases/lymphomas: Clinicopathological and molecular analysis

Seventy patients with various types of peripheral T-cell proliferative disease/lymphoma who manifested with prolonged fever, weight loss, anemia, lymphadenopathy, hepatosplenomegaly and elevated serum levels of alkaline phosphatase and/or lactate dehydrogenase were evaluated. Histopathological examination of the livers revealed T-cell infiltration into the hepatic sinusoids and portal tracts. The morphology of the infiltrated T cells varied from mature small lymphocytes to malignant lymphoid cells. The liver pathology was classified into four groups on the basis of cellular atypia. Group A and group B showed mature lymphoid cell infiltration; however, only group B had multiple large areas of hepatocellular necrosis. Group C showed atypical lymphoid cell infiltration and in group D malignant lymphoid cell infiltrates were demonstrated. The majority of the antigenic phenotypes of these T-cell infiltrates were CD3+, CD4-, CD8+, CD20-, CD45RO+, CD56-, CD57-, TIA-1+ and betaF1-. Epstein-Barr virus RNA in the nuclei of the infiltrated T cells was recorded in 38.6% of the patients and was more common in groups C and D. Patients in groups B, C and D had a very poor prognosis, median survival was only 1 month, whereas median survival in group A patients was 36 months. Chemotherapy was not effective in improving survival. Monoclonal band/s of T-cell receptors (TCR) beta and/or gamma gene rearrangements were detected in 88.6% of patients, and DNA-sequence analysis showed high identity to the human TCR germline gene.

Comparative analysis of NK/T-cell lymphoma and peripheral T-cell lymphoma in Korea: Clinicopathological correlations and analysis of EBV strain type and 30-bp deletion variant LMP1

Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases.

NK-cell related neoplasms in Osaka, Japan

The frequency of NK-cell related neoplasms was estimated among lymphoproliferative diseases diagnosed and treated in Osaka, Japan, from 1999 to 2003. The total number of registered cases was 1,400, among which 1,092 patients were diagnosed as having malignant lymphomas. There were 987 cases of non-Hodgkin's lymphoma (NHL) and 105 (9.6%) of Hodgkin's lymphoma. Immunophenotypic analysis revealed that 743 patients had B-cell lymphomas and 209 T/NK-cell lymphomas. Among the T/NK-cell lymphomas, 40 showed positive immunoreactivity for CD56, and thus they were judged to be NK/T-cell lymphomas. They included one blastic NK-cell lymphoma and 39 NK/T-cell lymphomas. NK/T-cell lymphomas were further divided into three categories based on the main site of lesions: nasal type (23 cases), non-nasal extranodal type (11 cases), and nodal type (5 cases). The positive rate of infection with the Epstein-Barr virus determined by in situ hybridization was 83%, 36%, and 25% in the nasal, non-nasal, and nodal type, respectively. A mosquito allergy was found in one patient with EBV-positive non-nasal NK/T-cell lymphoma. The present study showed that the frequency of NK-cell related neoplasms among all NHLs was 4% in an ATL-non-endemic area of Japan.

Pattern of Epstein-Barr virus association in childhood non-Hodgkin's lymphoma: Experience of University of Malaya Medical Center

The pattern of childhood non-Hodgkin's lymphoma (NHL) usually differs in adults. The most common subtypes are lymphoblastic, Burkitt's and anaplastic large cell lymphoma. Recent data indicate that a higher risk of developing lymphoma is associated in children of certain ethnic origins. The difference is probably related to the underlying etiological factors of these diseases, and Epstein-Barr virus (EBV) is a strong candidate. The present study aims to determine the disease pattern of childhood lymphomas in the University Hospital Kuala Lumpur, for a direct comparison to the reported data of adults from the same medical center. A total of 69 and 34 childhood NHL and Hodgkin's lymphomas, respectively, were retrieved. The most common subtypes were lymphoblastic (23 cases), Burkitt's (25 cases) and anaplastic large cell lymphomas (9 cases). Epstein-Barr virus association was more prevalent in B-cell (23%) than T-cell (12%) lymphomas. The most common EBV-associated tumor was Burkitt's lymphoma, and there was an increased risk of EBV association for Burkitt's lymphoma in Chinese patients. In conclusion, the pattern of childhood lymphoma in Malaysia is relatively similar to children elsewhere in the world. The EBV association of B- and T-NHL differs between children and adults from the same medical center because of differences in the subtype composition in these two age groups.

Analysis of p53, K-ras, c-kit, and beta-catenin gene mutations in sinonasal NK/T cell lymphoma in northeast district of China

Recently we reported the different frequencies of p53 and c-kit gene mutations among sinonasal NK/T cell lymphoma (NKTCL) in Korea, north China (Beijing), and Japan, suggesting some racial, environmental, or life-style differences as a possible cause of nasal tumorigenesis. In this study, gene mutations in p53, c-kit, K-ras, and beta-catenin gene were analyzed by polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) followed by direct sequencing in 20 cases of sinonasal NKTCL from northeast China (Shen Yang). Age of patients ranged from 5 to 63 (median, 40.0) years. p53 gene mutations were found in eight of 20 cases (40%), with exon 4 involvement in 10% of cases. The majority was missense mutations and G:C to A:T transition was predominant. The frequency of the c-kit and K-ras gene mutations was low (5%), while that of the beta-catenin gene was six of 20 cases (30%). From these findings, it is concluded that nasal NKTCL in northeast China shared common features with that in Korea in the younger onset of disease compared to that in Japan and lower frequency of p53 gene mutations with infrequent exon 4 involvement compared to that in Japan and north China. These differences might be caused by migration of susceptible populations or some environmental confounding factors.

Hypermethylation of death-associated protein (DAP) kinase CpG island is frequent not only in B-cell but also in T- and natural killer (NK)/T-cell malignancies

Death-associated protein (DAP) kinase is a pro-apoptotic serine/threonine kinase with a death domain, which is involved in apoptosis induced by interferon-gamma, tumor necrosis factor-alpha, and Fas ligand. Down-regulation of DAP kinase gene expression by hypermethylation of its promoter region might result in resistance to apoptotic cell death, and could provide a basis for tumor development. In the present study, we employed methylation-specific polymerase chain reaction to examine the methylation status of CpG islands in the DAP kinase gene in 19 cases of T-cell malignancies (including eight adult T-cell leukemia/lymphoma), 24 of natural killer (NK)/T-cell, and 34 of B-cell. Frequency of methylation was significantly higher in B-cell (27 of 34, 79.4%) than in T-cell malignancies (nine of 19, 47.4%) (P<0.05). Fifteen of 24 (62.5%) NK/T-cell lymphomas showed DNA methylation. One B-cell lymphoma cell line with DNA methylation was resistant to apoptotic stimuli, and treatment of the cells with a demethylating agent restored apoptotic cell death. These findings suggested that suppression of DAP kinase expression by DNA methylation might play a substantial role in the development of not only B-cell, but also T- and NK/T-cell lymphomas.

p53 Mutations in nasal natural killer/T-cell lymphoma from Mexico: association with large cell morphology and advanced disease

Nasal NK/T-cell lymphoma is a unique form of lymphoma highly associated with Epstein-Barr virus, and with a characteristic geographic distribution. Recently, we showed that p53 is overexpressed in a high percentage of nasal NK/T-cell lymphomas. The aim of this study was to analyze the status of the p53 gene, and correlate it with the expression of p53 protein and its downstream target, the cyclin-dependent kinase inhibitor p21, in a series of 25 cases of well-characterized nasal NK/T-cell lymphoma from Mexico. The highly conserved exons 5 to 8 of the p53 gene were amplified by polymerase chain reaction and screened for mutations by denaturing high-pressure liquid chromatography. Abnormal polymerase chain reaction products detected by denaturing high-pressure liquid chromatography and additional selected cases were sequenced. In addition, the incidence of loss of heterozygosity at the p53 locus was analyzed in 12 cases. Of the 25 patients, 17 were male and 8 female (M:F ratio, 2.1:1), with a median age of 43 years (range, 21 to 93 years). Morphologically, most of the cases were composed of a mixture of medium-sized cells and large transformed cells (21 cases), and four cases were composed exclusively of large transformed cells. Three different groups determined by p53 gene status and expression of p53 protein were identified: group 1 was p53 +/p53 mutated (five cases, all with p53 missense mutations). Morphologically, three of the five cases were composed of large cells. All five cases revealed overexpression of p53 in the majority of the tumor cells with a mean of 86%. Unexpectedly, three of these cases also showed overexpression of p21. Four of the five patients presented with clinical stage IVB and died with disease. Group 2 was p53+/p53 wild-type (10 cases). Histologically, nine cases were of the mixed type, and one of the large cell type. The percentage of p53 overexpressing cells was lower than in the previous group with a mean of 23%. p21 was positive in 7 of the 10 cases. Six patients in this group presented with clinical stages I to II and four patients with advanced disease (stage III and IV). Five patients are alive 12 to 120 months later (mean, 24 months), three with no evidence of disease. Group 3 was p53-/p53 wild-type (10 cases). All cases showed mixed cell morphology. p21 was positive in 5 of 10 cases. Four patients presented with clinical stage I to II and six patients with advanced disease. Four patients are alive with no evidence of disease 9 to 60 months later (mean, 10 months). Overall, p53 mutations were present in 24% (5 of 21) of the evaluable cases, all of them overexpressing p53 in the majority of tumor cells. Cases with p53 mutations were associated with large cell morphology (P = 0.0162) and presented more often with advanced stage disease. Loss of heterozygosity at chromosome 17p was found only in 2 of the 12 (17%) cases investigated, both cases showed p53 mutations of the remaining allele. P21 overexpression (60% of cases) is frequent in nasal NK/T-cell lymphoma and seems to be independent of p53 gene status. The overexpression of p53 and p21, independent of p53 mutations, although as yet not clear, might be the result of Epstein-Barr virus infection, and warrants further investigation.

Histological findings in biopsies from patients with cytoplasmic-antineutrophil cytoplasmic antibody (cANCA)-positive Wegener's granulomatosis

OBJECTIVE

Currently Wegener's granulomatosis (WG) is diagnosed from clinical features, a test for antineutrophil cytoplasmic antibody (ANCA) and histological confirmation. The purpose of our study was to evaluate histological findings, in particular those in the biopsy samples of head and neck region.

METHODS

Fifty-one biopsy specimens from 24 WG patients who were confirmed to be positive for cANCA were examined retrospectively.

RESULTS

Only 12 biopsies out of 51 biopsies (24%) were diagnosed as typical of WG, and diagnosis could be confirmed in only 10 patients (42%) as typical of WG from the results of multiple biopsy specimens.

CONCLUSION

In the diagnosis of WG. biopsy can be utilized restrictedly only in the cases when cANCA is negative or clinical symptoms are atypical of WG.

Host ethnicity influences non-Hodgkin's lymphoma subtype frequency and Epstein-Barr virus association rate: the experience of a multi-ethnic patient population in Malaysia

AIMS

The pattern of malignant lymphoma is known to vary in different populations. This study aims to elucidate the effect of ethnicity on subtype frequency of non-Hodgkin's lymphoma and EBV association rate.

METHODS AND RESULTS

A total of 232 reconfirmed lymphoma cases in Malaysian patients were retrieved from the archives in the Department of Pathology, University Hospital, Kuala Lumpur. There were 24 (10%) Hodgkin's and 208 (90%) non-Hodgkin's lymphomas, 173 of the latter were in adult group (aged > or = 15 years). The ethnic composition were 41 Malays, 107 Chinese, 21 Indians and four none of the above. A male : female ratio of 2.4 : 1 was observed. Complete immunohistochemical studies in 158 cases revealed 36 (23%) T-cell, 121 (76%) B-cell and one (1%) null-cell phenotype. Seventy-five percent of the T-cell lymphomas were peripheral T/NK-cell types. Among the classifiable lesions, low-grade/indolent lymphomas constituted 17%: 2% were the lymphocytic subtype and 10% were follicular lymphomas. Approximately one-third of the follicular lymphomas occurred in Indian patients. The largest group of high-grade lymphoma was diffuse large B-cell type (46%), followed by peripheral T/NK-cell (18%). A predominance of NK/T-cell lymphomas occurred in Chinese (5/7), and all were EBV associated. Burkitt's lymphoma accounted for 5% (eight cases), all were Chinese males, with a 38% EBV-association rate. The frequency of EBV-associated B-cell lymphoma is three times more common in Chinese than Malays. The EBV positivity rate among lymphomas in ethnic Malay, Chinese and Indian patients was 5%, 15% and 22%, respectively, and in T- and B-cell lymphomas was 36% and 7%, respectively.

CONCLUSIONS

This Malaysian series reveals differences in the subtype frequencies of non-Hodgkin's lymphomas and EBV association rate amongst patients of various ethnic groups residing in the same environment.

Characterization of novel natural killer (NK)-cell and gammadelta T-cell lines established from primary lesions of nasal T/NK-cell lymphomas associated with the Epstein-Barr virus

Studies on nasal T/natural killer (NK)-cell lymphoma have been hampered by its tendency to cause necrosis. Thus, the establishment of cell lines of this neoplasm would seem to be valuable. This study attempted to establish cell lines from primary lesions of this tumor, and successfully obtained 2 novel Epstein-Barr virus (EBV)-positive cell lines, SNK-6 and SNT-8, by means of high-dose recombinant interleukin 2. Flow cytometry showed that SNK-6 had an NK-cell phenotype, CD3- CD4- CD8- CD19- CD56+ T-cell receptor (TCR) alpha/beta- TCR gamma/delta-, whereas SNT-8 was CD3+ CD4- CD8- CD19- CD56+ TCR alpha/beta- TCR gamma/delta+. These were consistent with immunophenotypes of their original tumors, and the cell lines had monoclonal EBV clones identical to ones in their original tumors. Thus, the cell lines developed from cells forming the primary lesions. Genotypic analysis showed that SNK-6 had unrearranged TCR and immunoglobulin heavy-chain genes, supporting the conclusion that SNK-6 was of NK-cell lineage. On the other hand, SNT-8 had rearranged TCR beta-, gamma-, and delta-chain genes, and together with its phenotype, SNT-8 proved to be a gammadelta T-cell line. This is the first report of the establishment of cell lines from primary lesions of nasal T/NK cell lymphomas, and the results demonstrated that there are at least 2 lineages, NK- and gammadelta T-cell, in this neoplasm. Moreover, it has been suggested that nasal T/NK cell lymphomas of these lineages may belong to the same clinicopathologic entity because both types of cases shared common clinical and histopathologic features.

Clinicopathological features of Epstein-Barr virus-associated nasal T/NK cell lymphomas in southern Japan

OBJECTIVE

Nasal T/natural killer cell lymphomas (NTCL) are highly prevalent among Oriental populations. However the characteristic immunophenotype of NTCL is still controversial and it can be difficult to make a firm histologic diagnosis of malignancy. Therefore, 14 cases of NTCL in patients from southern Japan were evaluated for clinicopathological features and immunophenotypic status. Furthermore, the genetic variations in the latent membrane protein 1 (LMP-1) gene of Epstein-Barr virus (EBV)-related NTCL were evaluated.

METHODS

Biopsy specimens were fixed in formalin and embedded in paraffin before examination using in situ hybridization for EBV-encoded RNA-1 (EBER-1) as well as immunohistochemical staining for CD3, CD3epsilon, CD4, CD8, CD43, CD45RA, and CD45RO. To detect genetic variations, single-strand conformation polymorphism (SSCP) analysis and DNA sequencing were applied.

RESULTS

Clinically, 14 cases were divided into two groups. The first group consisting of eight patients showed good prognosis. The other group consisting of six patients showed poor prognosis. The vast majority of neoplastic cells in NTCL were EBER-1 positive. These cells did not express CD4, CD8, or CD45RA, but often expressed CD43 and CD45RO. In addition, they were negative for CD3 when stained with a mouse monoclonal antibody but stained for CD3epsilon when a rabbit polyclonal was used. The 3'-terminal of LMP-1 gene of seven cases were amplified and all of them have 30 base pair (bp) deletion.

CONCLUSION

NTCL are a heterogeneous mix of cell types although EBV-associated NTCL in patients from southern Japan appear to originate from natural killer cells rather than T cells, and also prognosis is variable and not always poor. The ability to make a firm diagnosis can be enhanced through the combined use of in situ hybridization and immunohistochemistry. High prevalence of the 30-bp deletions of the LMP-1 gene in EBV-related NTCL may also reflect the prevalence of the deletion variant in the normal population in Japan.

Sequences of cytotoxic T-lymphocyte epitopes in the Epstein-Barr virus (EBV) nuclear antigen-3B gene in a Japanese population with or without EBV-positive lymphoid malignancies

Latent infection antigens of EBV, including EBV nuclear antigens (EBNAs) and latent membrane proteins, are expressed in latently infected and immortalized B cells but work as target antigens for host cytotoxic T-lymphocyte (CTL) responses in an HLA class I-restricted manner. Among these latent antigens, the immunodominant CTL epitopes in EBNA3B (EBNA3B 399-408 and EBNA3B 416-424) are well characterized. Mutations and strain differences in these sequences, compared to the prototype A sequence, reduce CTL responses to latently infected B cells. These EBNA3B CTL epitopes in the normal Japanese population and in 2 lymphoid neoplasias, pyothorax-associated lymphoma (PAL) and nasal natural killer-cell lymphoma, were directly sequenced by PCR. Most EBV in peripheral blood leukocytes (PBLs) from healthy Japanese donors exhibited the prototype A sequence, with mutations in approximately 20% (3/16). The sequence of EBNA3B CTL epitopes in lymphoma tissue was obtained in 6 PAL cases, and 5 exhibited mutations or strain differences compared to the prototype A sequence. Furthermore, the EBNA3B sequence in PAL tissue was different from that in PBLs of the same patient or 1 of the sequences found in PBLs. However, the EBNA3B gene in nasal lymphoma tissues exhibited predominantly the prototype A sequence. Because PAL cells expressed EBNA3B mRNA, detected by RT-PCR, but nasal lymphoma cells did not, mutations and strain differences of the sequences of EBNA3B CTL epitopes were specific findings in EBNA3B-positive lymphomas.

Mutations of the p53 gene in nasal NK/T-cell lymphoma

Mutations of the p53 tumor suppressor gene are reported in various kinds of malignancies including lymphomas. However, p53 gene mutations in nasal NK/T-cell lymphoma have not been reported because most parts of tumors are necrotic and a small amount of living tumor tissues is available for the molecular study. Expression and mutations of the p53 gene were examined in the paraffin-embedded specimens of the nasal lesions from 42 Chinese (Beijing and Chengdu) and Japanese (Okinawa and Osaka) patients with nasal NK/T-cell lymphoma by the immunohistochemistry and single strand conformation polymorphism (SSCP) analysis of polymerase chain reaction (PCR) amplified products followed by direct sequencing. Thirty single-nucleotide substitution mutations were observed in 20 of 42 cases (47.6%). Among the 30 mutations, 18 were missense (mainly G:C to A:T transitions), 9 were silent, and 1 was a nonsense mutation. The remaining 2 mutations involved intron 5 and exon 5 terminal points. Abnormal expression of the p53 protein was also observed in 19 of 42 (45.2%) cases. The incidence was significantly (4-fold) higher in the cases of Osaka than those in other areas, although the incidence of p53 mutations in the cases of Osaka was one-half to one-third of those in the other three areas. The results may suggest some racial, environmental, or lifestyle differences in the cause of nasal tumorigenesis.

Radiotherapy for primary localized (stage I and II) non-Hodgkin's lymphoma of the oral cavity

PURPOSE

To assess the role of radiation therapy in the treatment of primary localized (Stage I: 24 cases and Stage II: 13 cases) non-Hodgkin's Lymphoma (NHL) of the oral cavity.

METHODS AND MATERIALS

In total, 37 patients (27 male, 10 female) with primary localized NHL of the oral cavity have been treated with radiotherapy alone (23 cases) or radiation with chemotherapy (14 cases). The age range was 29 to 86 years (median: 65). Clinical and treatment variables with potential prognostic significance for survival were evaluated by univariate and multivariate analysis. Of the 37 patients, 31 (84%) had intermediate-grade lymphomas and six (14%) had high-grade lymphomas. Four patients showed necrotic ulcer in the central portion of the hard palate.

RESULTS

The 5-year actuarial survival rate for all cases was 73%. The 5-year survival rates for intermediate-grade and high-grade lymphoma were 85% and 14%, respectively. Significant prognostic factors identified by the multivariate analysis were histologic grade of malignancy (p = 0.02) and central necrotic ulcer in the tumor (p = 0.02). Chemotherapy did not improve survival (p = 0.41).

CONCLUSIONS

Our analysis suggests that radiotherapy alone may be approved as the treatment for localized oral NHL with no ulceration and intermediate histology. However, patients with high-grade lymphoma and/or necrotic ulcer are difficult to cure with radiation alone and aggressive treatment should be advocated to improve survival.

Nasal lymphomas in Japan: a high prevalence of Epstein-Barr virus type A and deletion within the latent membrane protein gene

The majority of nasal lymphomas are of the natural killer (NK)/T cell lineage. We analyzed 33 specimens of nasal lymphoma from Japanese patients for Epstein-Barr virus (EBV). Phenotypic and genetic analyses showed 28 cases with NK/T cell type and 5 cases with B cell type. All NK/T lymphomas were of pleomorphic cell type except 2 large cell (centroblastoid) and one lymphoblastic lymphoma. All cases with nasal B cell lymphoma were of large (centroblastoid) cell type. EBV was detected in all cases of NK/T cell type with the exception of one lymphoblastic case, and was monoclonally integrated in all cases examined (14/14 cases). All but one case had subtype A of EBV infection with 30-base paired deleted LMP-1 gene. One case of B cell lymphoma showed the presence of EBV infection with subtype A and deletion of LMP-1. Our results indicate that the majority of nasal lymphomas in Japanese patients are of the nasal NK/T cell type, have pleomorphic morphology, a high prevalence of EBV with a monoclonal integration, subtype A and deleted LMP-1 gene. In contrast, nasal B cell lymphoma showed monomorphic appearance and rare EBV infection.

Histological and immunophenotypic profile of nasal NK/T cell lymphomas from Peru: high prevalence of p53 overexpression

Nasal NK/T-cell lymphoma is a unique form of lymphoma highly associated with Epstein-Barr virus (EBV). These lymphomas are rare in Western populations and much more prevalent in some Asian and Latin American countries. Although there are several sizable studies from Asian countries, the same is not true from South America. The aim of this study was to analyze a series of 32 cases of nasal T-cell lymphoma from Peru and to further extend the characterization of this disease. Immunohistochemistry was performed on paraffin sections using the following antibodies: CD20 (L26), CD45RO, CD3, Ki67, CD57, CD56, TIA-1, bcl-2, and p53. The presence of EBV was investigated with immunohistochemical analysis for latent membrane protein (LMP)-1 and in situ hybridization using an antisense riboprobe to EBER 1. The 32 patients included 18 men and 14 women (M:F ratio, 1.2:1), with a median age of 43 years (11 to 72). Three categories were identified: (1) Nasal NK/T cell lymphomas (28 cases): The morphology ranged from small or medium-sized cells to large transformed cells. Necrosis was present in 86% of the cases, and angioinvasion was seen in 36% of the cases. All cases were positive for CD45RO, CD3, and for TIA-1. CD56 was positive in 21 of 27 cases (78%), and CD57 was negative in all cases. EBER 1 positivity was identified in most of the tumor cells in 27 of 28 cases (96%), including the six cases in which CD56 was negative. Overexpression of p53 was detected in 24 cases (86%). (2) Blastic NK cell lymphoma (1 case): The neoplastic cells resembled those of lymphoblastic lymphoma. CD56 and CD45RO were positive; TIA-1, TdT, and EBER-1 were negative. (3) Peripheral T-cell lymphoma (PTCL) unspecified (3 cases): CD56, TIA-1, and EBER-1 were negative. Nasal lymphomas from Peru with a T cell phenotype are predominantly EBV-associated NK/T cell lymphomas, similar to those described in Asian countries. The expression of CD56, TIA-1, and EBER-1, in combination, are very useful markers for the diagnosis of nasal NK/T cell lymphoma in paraffin-embedded tissue. The differential diagnosis of T-cell lymphomas in the nasal region should include rare cases of PTCL unspecified and the blastic variant of NK cell lymphoma. P53 is overexpressed in 86% of the cases. The significance of this finding with regard to clinical behavior and prognosis remains to be determined.