Epidemiology of lymphomas

Lymphomas in patients with neurofibromatosis type 1 (NF1): another malignancy in the NF1 syndrome?

Neurofibromatosis type 1 (NF1) is an autosomal dominant multisystem syndrome caused by mutations in the neurofibromin 1 (NF1) gene that encodes for the protein neurofibromin acting as a tumour suppressor. Neurofibromin functions primarily as a GTPase-activating protein for the Ras family of oncogenes, which activates many signalling pathways for cell proliferation and differentiation; without neurofibromin, Ras is constitutively activated, thereby turning on many downstream signalling pathways related to oncogenesis. Patients with NF1 have a well known predisposition for certain types of malignancies including malignant peripheral nerve sheath tumours, gliomas, and breast cancers, as well as a potential association of NF1 with lymphoproliferative disorders such as lymphomas. In this article, we review the pathophysiology and tumourigenesis of NF1, previously reported cases of cutaneous lymphomas in NF1 patients along with our case demonstration of a NF1-associated scalp B-cell lymphoma, and NF1-associated extra cutaneous lymphomas. The diagnosis of lymphomas particularly cutaneous lymphomas may be difficult in NF1 patients as they often have skin lesions and/or cutaneous/subcutaneous nodules or tumours like neurofibromas, which raises the possibility of underdiagnosed cutaneous lymphomas in NF1 patients. We also comprehensively discuss the association between NF1 and lymphomas. In summary, most studies support a potential association between NF1 and lymphomas. Further investigation is needed to clarify the association between NF1 and lymphomas in order to bring clinical awareness of possibly underdiagnosed NF1-associated lymphomas and individualised management of NF1 patients to practice.

Long noncoding RNAs (lncRNAs) in human lymphomas

Lymphomas are a diverse group of haematologic malignancies, which occur in infection-fighting cells of the lymphatic system. Long non-coding RNAs (lncRNAs) are non-coding RNAs, which have recently received significant attention as the main mediators of gene expression. In this review, we summarize the current knowledge on lncRNAs involved in lymphomas, their molecular functions, as well as their potential clinical value. Relevant literature was identified by a PubMed search of English language papers using the following terms: Lymphoma, LncRNA, leukemia, proliferation, apoptosis, and prognosis. LncRNAs are imperative for lymphoma carcinogenesis through affecting apoptosis, cell proliferation, invasion, and response to chemotherapy. The expression level of lncRNAs can affect chemotherapy-induced apoptosis. Taken together, lncRNA dysregulation in lymphoma cells is not only an epiphenomenon but also lncRNA transcription is critically related to the initiation and progression of lymphomas. Aberrant expression of lncRNAs can lead to the transformation of normal lymphocytes into lymphoma cells.

Dysregulation of miRNAs in DLBCL: Causative Factor for Pathogenesis, Diagnosis and Prognosis

MicroRNA is a small non-coding RNA (sncRNA) involved in gene silencing and regulating post-transcriptional gene expression. miRNAs play an essential role in the pathogenesis of numerous diseases, including diabetes, cardiovascular diseases, viral diseases and cancer. Diffuse large B-cell lymphoma (DLBCL) is an aggressive non-Hodgkin’s lymphoma (NHL), arising from different stages of B-cell differentiation whose pathogenesis involves miRNAs. Various viral and non-viral vectors are used as a delivery vehicle for introducing specific miRNA inside the cell. Adenoviruses are linear, double-stranded DNA viruses with 35 kb genome size and are extensively used in gene therapy. Meanwhile, Adeno-associated viruses accommodate up to 4.8 kb foreign genetic material and are favorable for transferring miRNA due to small size of miRNA. The genetic material is integrated into the DNA of the host cell by retroviruses so that only dividing cells are infected and stable expression of miRNA is achieved. Over the years, remarkable progress was made to understand DLBCL biology using advanced genomics and epigenomics technologies enabling oncologists to uncover multiple genetic mutations in DLBCL patients. These genetic mutations are involved in epigenetic modification, ability to escape immunosurveillance, impaired BCL6 and NF-κβ signaling pathways and blocking terminal differentiation. These pathways have since been identified and used as therapeutic targets for the treatment of DLBCL. Recently miRNAs were also identified to act either as oncogenes or tumor suppressors in DLBCL pathology by altering the expression levels of some of the known DLBCL related oncogenes. i.e., miR-155, miR-17-92 and miR-21 act as oncogenes by altering the expression levels of MYC, SHIP and FOXO1, respectively, conversely; miR-34a, mir-144 and miR-181a act as tumor suppressors by altering the expression levels of SIRT1, BCL6 and CARD11, respectively. Hundreds of miRNAs have already been identified as biomarkers in the prognosis and diagnosis of DLBCL because of their significant roles in DLBCL pathogenesis. In conclusion, miRNAs in addition to their role as biomarkers of prognosis and diagnosis could also serve as potential therapeutic targets for treating DLBCL.

Rare Complications of Acute Appendicitis: A Case Report

Introduction

Appendicitis is a common disease, and as we have improved in early diagnosis and management of this disease process, late stage complications have become extremely rare, but can have indolent presentations.

Case Report

A 37-year-old male with no past medical history presented to the emergency department (ED) with vague abdominal pain as well as 12 days of cyclical fever. He had no significant findings on laboratory workup with the exception of a mild aspartate transaminase and alanine transaminase and relative neutrophilia between outpatient, urgent care, and ultimate ED visit. His ED workup included cross-sectional imaging of his abdomen revealing multiple liver abscesses and septic thrombophlebitis secondary to ruptured appendicitis.

Conclusion

Liver abscesses and septic thrombophlebitis are an extremely rare complication of appendicitis that has only been documented twice previously.

Validación de la escala FACT-Lym para la evaluación de la calidad de vida en pacientes colombianos con linfoma

Introducción. Los instrumentos para medir la calidad de vida se deben validar antes de ser utilizados en diferentes contextos culturales. En la actualidad existe una escala específica (FACT-Lym) para medir la calidad de vida en pacientes con linfoma, sin embargo esta no ha sido validada en Colombia.Objetivo. Establecer las propiedades clinimétricas de la escala FACT-Lym en pacientes colombianos con linfoma. Materiales y métodos. Se realizó un estudio de validación de escalas según la teoría clásica de test. Se aplicó la escala FACT-Lym a 301 pacientes del Instituto Nacional de Cancerología diagnosticados con diferentes tipos de linfoma y se registraron sus datos sociodemográficos y clínicos. El análisis estadístico incluyó análisis factorial exploratorio, análisis factorial confirmatorio, validez de constructo, consistencia interna, confiabilidad test re-test y sensibilidad al cambio.Resultados. El análisis factorial exploratorio confirmó una estructura de dos factores de la escala, mientras que el análisis confirmatorio mostró un adecuado ajuste del modelo estructural. La consistencia interna se midió con el coeficiente alfa de Cronbach (>0.8 en la escala global y en cada uno de los factores). Se encontraron valores de correlación significativamente diferentes a cero entre la FACT-Lym y los dominios de la escala FACT-G. No se observaron cambios significativos en ninguno de los dominios de la FACT-Lym luego de completar o suspender el tratamiento.Conclusiones. La validación de la escala FACT-Lym en Colombia mostró que esta tiene una estructura factorial consistente y una adecuada confiabilidad. Sin embargo, su sensibilidad al cambio debe verificarse evaluando su desempeño en otras poblaciones.

C-MYC, BCL2 and BCL6 Translocation in B-cell Non-Hodgkin Lymphoma Cases

C-MYC, BCL2 and BCL6 genes are the most commonly oncogenes involved in B-Cell lymphomas. Translocations of these oncogenes are associated with an aggressive clinical course. This study aims to elucidate the patterns of BCL6, BCL2 and C-MYC gene aberrations among Malaysian B-cell Non-Hodgkin Lymphoma (NHL) using fluorescence in situ hybridization (FISH). Eighty-one B-cell NHL tissue blocks were retrieved between the year 2011 to 2015 and investigated using immunohistochemistry and interphase FISH dual colour break-apart probes of BCL2, BCL6, C-MYC and IgH. A significant difference was detected between the nodal and extranodal sites in all the BCL2 (p=0.01), C-MYC (p=0.03) and IgH (p=0.006) cases except for BCL6 (p=0.2). Our study showed that BCL6 had the highest gene translocation while BCL2/BCL6 had the most mixed aberrations of gain copies and translocation, however no mixed aberrations of gain copies and translocation was found in C-MYC. None of the mixed gain copies and translocation was found in any of the germinal centre B-cell (GCB) subtype of Diffuse Large B-cell Lymphoma, however, five were found in BCL6 and IgH gene in the non-GCB subtype; while mixed gain copies and translocation cases of BCL2 gene was found in the Follicular Lymphoma cases only. The study found interesting findings of BCL2, C-MYC and IgH gene aberrations between nodal and extranodal sites. This information might benefit future study in predicting prognosis and determine effective therapeutic strategies in the multi-ethnic populations of Malaysia as well as the Asian population.

The Relation of Obesity-Related Hormonal and Cytokine Levels With Multiple Myeloma and Non-Hodgkin Lymphoma

This article presents the first detailed overview of the mechanisms that may underlie the relation of obesity with B-cell non-Hodgkin lymphomas (NHLs) and multiple myeloma (MM). Epidemiologic studies, including meta-analyses of prospective cohorts, have reported that the risks of NHL and MM are significantly increased in obese, relative to normal weight, women and men. Accumulating experimental and clinical evidence suggests that inflammatory cytokines, hyperinsulinemia, and sex hormones could play a role in the association of obesity with B-cell NHL and MM carcinogenesis. There is, however, a paucity of data published from appropriate large prospective cohort studies, and studies concurrently measuring these correlated factors, to formally determine the likely biologic factors driving the relationship of obesity with NHL and MM. Additional strengths and weaknesses of the current literature, as well as study design issues that need to be considered in conducting these studies, such as the exclusion of type 2 diabetics or postmenopausal women using hormone therapy, are discussed.

Health Disparities and the Global Landscape of Lymphoma Care Today

Lymphoma encompass a wide variety of distinct disease entities, including, but not limited to, subtypes of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL). In the last 3 decades, therapeutic advancements have resulted in substantial improvements in lymphoma outcome. In most high-income regions, HL is a largely curable disease and for patients with two frequent subtypes of NHL, diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL), survival has dramatically improved with the incorporation of rituximab as a standard treatment approach. Despite these advances, outcomes vary between and across populations. This review will provide updated information about health disparities in lymphoma in the United States and across the globe.

Farming and mortality rates attributed to non-Hodgkin's lymphoma in Taiwan

Previous studies suggested an elevated risk of non-Hodgkin's lymphoma (NHL) among farmers. To date, no apparent study examined the association between farming and NHL in Asian countries. The aim of this study was to investigate whether farmers in Taiwan exhibited an increased risk of mortality attributed to NHL. To this end, a mortality odds ratio (MOR) study was conducted to estimate the relative risk of mortality attributed to NHL for farmers in Taiwan. Data on the decedents enrolled in this investigation were derived from the death certificate database for the period 1997-2009. The study group comprised individuals who died from NHL and who were 50 years or older. The control group consisted of subjects who died from all other causes, excluding cancers, in the corresponding age group. Multiple logistic regression analysis was performed to compute the MOR, with adjustments for gender, age at death, year of death, marital status, and urbanizational levels. Among 32,456 deceased farmers, 205 died due to NHL. Farmers were found to have a nonsignificantly higher MOR than nonfarmers. This risk estimate is similar to estimates in previous meta-analyses. The MOR for NHL was higher among farmers who died 65 years or older than among those who died at younger ages. The findings indicate that farming in Taiwan may increase the risk of death attributed to NHL. Exposure to pesticides might be an influential factor contributing to high risk of mortality attributed to NHL among farmers and therefore needs to be further investigated.

Childhood cancer in small geographical areas and proximity to air-polluting industries

AIM

Pediatric cancer has been associated with exposure to certain environmental carcinogens. The purpose of this work is to analyse the relationship between environmental pollution and pediatric cancer risk.

METHOD

We analysed all incidences of pediatric cancer (<15) diagnosed in a Spanish region during the period 1998-2015. The place of residence of each patient and the exact geographical coordinates of main industrial facilities was codified in order to analyse the spatial distribution of cases of cancer in relation to industrial areas. Focal tests and focused Scan methodology were used for the identification of high-incidence-rate spatial clusters around the main industrial pollution foci.

RESULTS

The crude rate for the period was 148.0 cases per 1,000,0000 children. The incidence of pediatric cancer increased significantly along the period of study. With respect to spatial distribution, results showed significant high incidence around some industrial pollution foci group and the Scan methodology identify spatial clustering. We observe a global major incidence of non Hodgkin lymphomas (NHL) considering all foci, and high incidence of Sympathetic Nervous System Tumour (SNST) around Energy and Electric and organic and inorganic chemical industries foci group. In the analysis foci to foci, the focused Scan test identifies several significant spatial clusters. Particularly, three significant clusters were identified: the first of SNST was around energy-generating chemical industries (2 cases versus the expected 0.26), another of NHL was around residue-valorisation plants (5 cases versus the expected 0.91) and finally one cluster of Hodgkin lymphoma around building materials (3 cases versus the expected 2.2) CONCLUSION: Results suggest a possible association between proximity to certain industries and pediatric cancer risk. More evidences are necessary before establishing the relationship between industrial pollution and pediatric cancer incidence.

Head and neck lymphomas - a retrospective ten-year observation

AIM OF THE STUDY

Lymphomas are a heterogeneous group of tumours of lymphoid tissue in which there is an abnormal proliferation of cells of the lymphatic system. The literature notes a gradual increase in the incidence of this type of cancer in the whole population. The aim of the study was to evaluate whether the above tendency occurs in the head and neck area.

MATERIAL AND METHODS

In the years 2005-2014, at the Otolaryngology and Laryngological Oncology Department of the Upper Silesian Medical Centre in Katowice, 77 cases of lymphoma were recorded, 58 of which were analysed in terms of location, histological type, age and sex of the patient, and the presence of risk factors.

RESULTS

The vast majority of them were non-Hodgkin's lymphomas (NHL) - 67.53%. Hodgkin's lymphomas (HL) accounted for only a small fraction of diagnoses (7.79%). In terms of histopathological types, in most cases of NHL, there occurred diffuse large B-cell lymphomas (DLBCL) - 51.92%. The most common location was the lymph nodes, representing the location of the primary lesion in more than half of the cases. As regards the extranodal location, the Waldeyer ring dominated (54.54%) along with the palatal tonsil (40.90%). There has been a significant upward trend, especially in the incidence of NHL.

Clinical findings of extranodal SNT lymphoid malignancies in a four-decade single-centre series

Sinonasally located lymphoid malignancies are rare lesions with first symptoms similar to other obstructive conditions. Additionally, they often coexist with nasal inflammation and mucosal necrosis. Therefore, time from the first symptoms to diagnosis tends to be long. Awareness and early diagnosis of this disease entity could improve treatment outcome. Altogether, 142 patients with sinonasal or nasopharyngeal (i.e. sinonasal tract, SNT) lymphoid malignancies, diagnosed and treated at the Helsinki University Hospital, during a 39-year period from 1975 to 2013, were retrospectively reviewed. There were 90 males (63 %) and 52 females (37 %) with a median age of 64 years (range 26-92). Eighty-four percent of the patients had primary diseases and 16 % had relapses of lymphoid malignancies primarily diagnosed at other locations. The mean duration of symptoms prior to diagnosis was 4.8 months (range 0.5-24). The most common histological entity was diffuse large B-cell lymphoma (43 %), followed by plasmacytoma (18 %). The most common location was nasopharynx (58 %) followed by nasal cavity (44 %) and paranasal sinuses (35 %). Sixty-nine percent of the lesions were at a single anatomic location of the sinonasal tract. Fifty-two percent of the cases were of Ann Arbor Stage I. Lymphoid malignancies form an important and diverse group in the differential diagnosis of SNT tumours. They most often present with general obstructive nasal symptoms due to tumour location. Most of them are primary lesions, highlighting the importance of an accurate diagnosis as early as possible.

Gender and ethnic differences in incidence and survival of lymphoid neoplasm subtypes in an Asian population: Secular trends of a population-based cancer registry from 1998 to 2012

Descriptive epidemiology on incidence and survival by lymphoid neoplasm (LN) subtypes using the 2008 World Health Organisation (WHO) classification remained limited in Asia. The aim of this study was to evaluate whether gender and ethnic differences in incidence and survival of LN subtypes existed using the Singapore Cancer Registry (SCR) from 1998 to 2012. We derived age standardised incidence rates (ASIRs) by the direct standardisation method and 5-year relative survival (RSR) by the Ederer II method and period approach. Five-year observed survival (OS) was obtained for each ethnicity. Malays had the highest ASIR of total LNs among the three ethnicities for each time period. The largest increase in 5-year RSR subtypes was follicular lymphoma from 43.8% in 1998-2002 to 82.3% in 2008-2012; followed by chronic lymphocytic leukaemia (CLL)/small lymphocytic lymphoma (SLL) from 48.1% in 1998-2002 to 77.9% in 2008-2012. Although males had higher incidence than females in each time period, females had greater 5-year RSR for follicular lymphoma (89.8% in 2008-2012 for females vs. 76.6% in 2008-2012 for males) and CLL/SLL (78.7% in 2008-2012 for females vs. 76.7% in 2008-2012 for males). All three ethnicities experienced an overall increase in 5-year OS for mature B-cell lymphoma, with Indians experiencing the greatest increase (37.1% in 1998-2002 to 61.1% in 2008-2012), followed by Malays (30.8% in 1998-2002 to 48.7% in 2008-2012) and then Chinese (36.4% in 1998-2002 to 51.3% in 2008-2012). Our study demonstrated that improved mature B-cell lymphoma survival was not only observed in the West, but also in Singapore.

Lymphomas in Ile-Ife, Nigeria: Immunohistochemical Characterization and Detection of Epstein-Barr virus Encoded RNA

BACKGROUND

The proper histopathological characterization of malignant lymphomas requires the use of immunohistochemistry along with other molecular pathology techniques.

MATERIALS AND METHODS

Malignant lymphomas histologically diagnosed in our hospital were reclassified according to the WHO scheme using immunohistochemistry while in-situ hybridization was performed for the detection of Epstein-Barr virus encoded RNA.

RESULTS

There were 83 cases of lymphoma. The male to female ratio was 1.9:1 while the overall mean age was 41.7 years. Non-Hodgkin lymphomas (NHL) constituted about 79.5% of cases. The majority of cases (98.8%) were B-cell lymphomas. Nine subtypes of lymphomas were identified with diffuse large B-cell lymphomas (56.4% of which were of the germinal centre type) constituting the largest group (47.0%). Intermediate and high grade subtypes were more common. The majority of cases (72.3%) were nodal lymphomas with cervical lymph node being the commonest site (48.2%). Only classical Hodgkin lymphoma (HL) (20.5%) was seen of which the mixed cellularity subtype was the most common. Epstein Barr virus (EBV) encoded ribonucleic acid was detected in 7 cases (8.4%) including 4 cases of HL, 2 cases of Burkitt lymphoma and the only case of plasmablastic lymphoma. About five cases were reclassified as non-lymphoid malignant lesions.

CONCLUSION

Immunohistochemistry is vital to the proper classification of lymphomas even in a resource poor environment. Although nine subtypes of lymphomas were identified, diffuse large B-cell lymphomas formed the largest single group. Epstein-Barr virus probably plays an important role in lymphomatogenesis in this environment. A larger multicentre study is required to prove this.

Clinical characteristics, pathological distribution, and prognostic factors in non-Hodgkin lymphoma of Waldeyer's ring: nationwide Korean study

BACKGROUND/AIMS

In Asia, the incidence of non-Hodgkin lymphoma (NHL) has increased in recent decades. Waldeyer's ring (WR) is the most common site of NHL involving the head and neck. In this study, the pathological distribution of WR-NHL and its clinical features were analyzed retrospectively.

METHODS

From January 2000 through December 2010, we analyzed the medical records of 328 patients from nine Korean institutions who were diagnosed with WR-NHL.

RESULTS

The study group comprised 197 male and 131 female patients with a median age of 58 years (range, 14 to 89). The rate of localized disease (stage I/II) was 64.9%, and that of low-risk disease (low/low-intermediate, as defined by the International Prognostic Index) was 76.8%. Diffuse large B-cell lymphoma (DLBCL; 240 patients, 73.2%) was the most common pathologic subtype, followed by peripheral T-cell lymphoma (14 patients, 4.3%) and nasal NK/T-cell lymphoma (14 patients, 4.3%). WR-NHL occurred most frequently in the tonsils (199 patients, 60.6%). Extranodal involvement was greater with the T-cell subtype (20 patients, 42.5%) compared with the B-cell subtype (69 patients, 24.5%). Multivariate analyses showed that age ≥ 62 years, T-cell subtype, and failure to achieve complete remission were significant risk factors for overall survival.

CONCLUSIONS

DLBCL was found to have a higher incidence in Korea than those incidences reported by other WR-NHL studies. T-cell lymphoma occurred more frequently than did follicular lymphoma. T-cell subtype, age ≥ 62 years, and complete remission failure after first-line treatment were significant poor prognostic factors for overall survival according to the multivariate analysis.

Organic food consumption and the incidence of cancer in a large prospective study of women in the United Kingdom

BACKGROUND

Organically produced foods are less likely than conventionally produced foods to contain pesticide residues.

METHODS

We examined the hypothesis that eating organic food may reduce the risk of soft tissue sarcoma, breast cancer, non-Hodgkin lymphoma and other common cancers in a large prospective study of 623 080 middle-aged UK women. Women reported their consumption of organic food and were followed for cancer incidence over the next 9.3 years. Cox regression models were used to estimate adjusted relative risks for cancer incidence by the reported frequency of consumption of organic foods.

RESULTS

At baseline, 30%, 63% and 7% of women reported never, sometimes, or usually/always eating organic food, respectively. Consumption of organic food was not associated with a reduction in the incidence of all cancer (n=53 769 cases in total) (RR for usually/always vs never=1.03, 95% confidence interval (CI): 0.99-1.07), soft tissue sarcoma (RR=1.37, 95% CI: 0.82-2.27), or breast cancer (RR=1.09, 95% CI: 1.02-1.15), but was associated for non-Hodgkin lymphoma (RR=0.79, 95% CI: 0.65-0.96).

CONCLUSIONS

In this large prospective study there was little or no decrease in the incidence of cancer associated with consumption of organic food, except possibly for non-Hodgkin lymphoma.

Changing trend of Epstein-Barr virus association in Hodgkin lymphoma in the Republic of Korea

Hodgkin lymphoma (HL) in resource-poor population shows an early childhood peak with predominance of mixed cellularity (MCHL) and high Epstein-Barr virus (EBV) association, whereas HL in resource-rich population has a peak in ages 15-29 years with the predominance of nodular sclerosis (NSHL) and low EBV association. We examined the changing trend of HL in association with EBV in Korea in 385 cases of HL (1980-2011). Data from 1980-1995 and 1996-2011 were compared. Age distribution showed a marked decrease in children (age < 15 years) (21.0 % to 8.6 %, p = 0.004) and sharp increase in young adults (ages 15-29 years) and ages 30-59 years. Male predominance decreased from 3.04 to 1.57. Predominant subtype changed from MCHL to NSHL; MCHL fell from 53.3 % to 26.4 % (p < 0.001), and NSHL rose from 24.8 % to 58.2 % (p < 0.001). EBV-positive HL decreased from 66.7 % to 38.2 %. However, in young adult females, EBV positive cases increased, contributing to the peak in this age group. Epidemiology of HL in Korea is rapidly changing into a Western pattern concurrent with the socioeconomic changes. Analysis of the cases stratified by EBV status and sex identified a smaller hidden peak in the young adult age, which confirms the four disease hypothesis proposed by Jarrett. We propose EBV testing as an essential component in epidemiologic study of Hodgkin lymphoma.

A collaborative nationwide lymphoma study in Lebanon: incidence of various subtypes and analysis of associations with viruses

Incidence of various Hodgkin (HL) and non-Hodgkin lymphoma (NHL) subtypes and association with viruses in Lebanon are not known. We undertook a nationwide study of 272 patients diagnosed with lymphoma in 2007. HL comprised 32.7 % (n = 89) of cases while NHL represented 67.3 % (n = 183). Consistent with the literature, nodular sclerosis was the most predominant HL subtype (n = 57/89). Among NHL, B-cell NHL represented 88 % (n = 161/183), T-cell NHL 9 % (n = 17/183), whereas in 2.7 % it was not classifiable. The B-cell NHL comprised predominantly diffuse large B-cell lymphoma (46 %) and follicular lymphoma (23 %). 81 cases were reviewed by a panel of pathologists with 87.6 % concordance rate. Serology was negative for hepatitis C in 122 tested cases. HIV was positive in 2 cases. Two adult T-cell leukemia/lymphoma were HTLV-I positive. EBV IgG were positive in 88.5 % of cases. 38 EBV seropositive cases [27 NHL (24 B-cell, 3 T-cell) and 11 HL] were studied for EBV genome expression using EBV-encoded RNA (EBER)-in situ hybridization. EBER expression was positive in 8 (21 %) cases (6 HL, 2 T-cell NHL). The distribution of lymphoma subtypes in Lebanon appears similar to that of Western countries. The high rate of EBV positivity in HL and T-cell lymphoma by EBER deserves further investigation.

Growth inhibition and apoptosis of human B-cell lymphoma in vitro and in vivo by Bcl-2 short hairpin RNA

Bcl-2 is overexpressed in various types of human tumors, including Burkitt's lymphoma, and it is involved in tumorigenesis and chemoresistance, therefore, it is regarded as a potential target of gene therapy. In this study, RNA interference using short hairpin RNA (shRNA)-mediated RNA interference was introduced into Burkitt's lymphoma Raji cells to validate its effects on Bcl-2 expression and cell proliferation in vitro and in vivo. We constructed two types of Bcl-2 shRNA plasmid (pGenesil-1-Bcl-2-1 and pGenesil-1-Bcl-2-2) and negative control shRNA plasmid (pGenesil-1-NC) and stably transfected them into Raji cells. The expression levels of Bcl-2 mRNA and protein were assayed by RT-PCR, flow cytometry and western blotting. Cell proliferation was determined by cell count assay. The antitumor activities and apoptosis of the two types of Bcl-2 shRNA plasmid were evaluated in BALB/c nude mice bearing Burkitt's lymphoma inoculated with Raji cells. The results showed that the expression levels of Bcl-2 mRNA and protein decreased, compared with either the pGenecil-1-NC or the untransfected cell group (P<0.05). The cell proliferation assay showed that Bcl-2 shRNA significantly inhibited the growth of Raji cells (P<0.01). Furthermore, the tumor growth of the Bcl-2 shRNA cell group was dramatically lower and smaller than that of the negative control or untransfected cell group (P<0.01). Bcl-2 protein expression in the untransfected and the pGenesil-1-NC group were markedly higher than that of the pGenesil-1-Bcl-2-1 and the pGenesil-1-Bcl-2 group by immunohistochemistry (both P<0.01) and the results using transmission electron microscopy showed that Bcl-2 shRNA significantly induced Raji cell apoptosis. Additionally, the inhibition effect of pGenesil-1-Bcl-2-1 was better than that of pGenesil-1-Bcl-2-2. It has been suggested that vector-based Bcl-2 shRNA could effectively reduce the expression of Bcl-2 and induce apoptosis and growth inhibition of Burkitt's lymphoma Raji cells. Vector-based Bcl-2 shRNA could be a potential gene therapeutic strategy against human Burkitt's lymphoma.

Frequency and distribution of lymphoma types in a tertiary care hospital in South India: analysis of 5115 cases using the World Health Organization 2008 classification and comparison with world literature

This study aimed to analyze the distribution of lymphoid neoplasms in a single tertiary care center in India using the World Health Organization (WHO) 2008 classification. Histological material of 5115 patients with histopathological diagnosis of lymphoma, diagnosed over a period of 10 years (2001-2010), was analyzed retrospectively. Hodgkin lymphoma (HL) constituted 21.3% (n = 1089) and non-Hodgkin lymphomas (NHLs) constituted 78.7% (n = 4026). Of these, B-cell neoplasms accounted for 78.6% (n = 3166) and T-cell/natural killer (NK)-cell neoplasms 20.2% (n = 815) of the NHLs. The commonest subtype of NHL was diffuse large B-cell lymphoma (n = 1886, 46.9%). The frequency of peripheral T-cell/NK-cell lymphomas in this study was higher than in the Western literature but less than the frequency documented in some Asian countries. Similar to the Western literature but in contrast to previous Indian studies, peripheral T-cell lymphoma, not otherwise specified (PTCL NOS) (n = 238) was the commonest histological subtype of T-cell/NK-cell NHL in this study and constituted 5.9% of the total NHLs. Mixed cellularity (MC-CHL) (n = 488, 45%) was the major subtype of HL. Primary extranodal lymphoma (ENL) accounted for 32.8% (n = 1321) of all NHLs and most frequently involved the gastrointestinal tract. This study also documents the frequency of many rare types of lymphoma in South India.

Diabetes, insulin use, and non-Hodgkin lymphoma mortality in Taiwan

The objective was to evaluate non-Hodgkin lymphoma (NHL) mortality trends and mortality rate ratios between diabetes patients and the general population, and to study NHL risk factors among diabetes patients in Taiwan. A cohort of 80 397 patients with type 2 diabetes mellitus older than 45 years was recruited in 1995-1998 and followed up until 2006. Age-standardized NHL mortality in 1995-2006 was calculated. Non-Hodgkin lymphoma risk factors in diabetes patients were evaluated using Cox regression. Age-standardized NHL mortality trend was steady. Eighty-two male and 69 female diabetes patients died of NHL (crude mortality rates, 35.1 and 23.0 per 100 000 person-years, respectively; corresponding overall mortality rate ratios comparing diabetes patients to the general population, 2.06 and 2.14). The mortality rate ratios were 1.47, 2.33, and 2.78 for men aged at least 65, 55 to 64, and 45 to 54 years, respectively; the corresponding ratios for women were 1.48, 2.22, and 2.79. Age and male sex were significant risk factors, whereas insulin use, diabetes duration, smoking, body mass index, and area of residence were not. Diabetes duration became a significant factor after excluding patients who died of NHL within 5 years of diabetes diagnosis. Patients with diabetes have a higher risk of mortality from NHL, but insulin use is not associated with NHL mortality. Future studies are needed to fully elucidate any association between increased mortality rate ratio and younger age as well as the lack of association between NHL and insulin use demonstrated herein.

Epidemiologic overview of malignant lymphoma

Malignant lymphoma encompasses a wide variety of distinct disease entities. It is generally more common in developed countries and less common in developing countries. The East Asia region has one of the lowest incidence rates of malignant lymphoma. The incidence of malignant lymphoma around the world has been increasing at a rate of 3-4% over the last 4 decades, while some stabilization has been observed in developed countries in recent years. The reasons behind this lymphoma epidemic are poorly understood, although improving diagnostic accuracy, the recent AIDS epidemic, an aging world population and the increasing adoption of cancer-causing behaviors are suggested as contributing factors. Etiologies of malignant lymphoma include infectious agents, immunodeficiency, autoimmune disease, exposure to certain organic chemicals, and pharmaceuticals. The distribution of many subtypes exhibit marked geographic variations. Compared to the West, T/natural killer (NK) cell lymphomas (T/NK-cell lymphoma) and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) are relatively more common, whereas other B-cell lymphomas, particularly follicular lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma, are less common in Asia. Some subtypes of T/NK-cell lymphomas defined by Epstein-Barr virus association are predominantly Asian diseases, if not exclusively so. Both ethnic and environmental factors play roles in such diversity. In this review, we discuss the geographic distribution and etiology of malignant lymphoma, as well as the trend.

Intake of vitamins D and A and calcium and risk of non-Hodgkin lymphoma: San Francisco Bay Area population-based case-control study

Several nutrients identified as potentially cancer protective have been inconsistently associated with non-Hodgkin lymphoma (NHL) risk. Dietary history data, including use of vitamin supplements, were collected using a semiquantitative food frequency questionnaire administered during in-person interviews with 4,133 participants (2,052 cases, 2,081 controls) in a San Francisco Bay Area population-based case-control study. Data were used to determine the association of intake levels of vitamins D and A and calcium with risk of NHL and NHL subtypes. Odds ratios (OR) and 95% confidence intervals (CI) were computed as estimates of relative risk using adjusted unconditional logistic regression. Increasing vitamin D intake from food and supplements was positively associated with NHL risk in men (5th quintile: OR = 1.6, 95% CI = 1.0-2.4, P(trend) = 0.07) and with diffuse large B-cell lymphoma (DLBCL) in women and men (5th quintile: OR = 1.6, 95% CI = 1.0-2.5, P(trend) = 0.02); that was largely due to the effect in men (P(trend) = 0.03). These results do not support a strong role for vitamin D intake with NHL risk, with the exception of a potential association for DLBCL risk in men. Our results should be interpreted conservatively until further investigation in larger pooled studies can be conducted to better assess the role of vitamin D intake in lymphomagenesis.

The Relationship between Exposure to Pesticides and the Occurrence of Lymphoid Neoplasm

BACKGROUND

The etiology of malignant lymphoma is still largely unknown. This study determines the relationship between exposure to pesticides and the occurrence of lymphoid neoplasms in Shiraz, Southern Iran.

METHODS

Between 2007 and 2008, in a case control study conducted in Nemazee Hospital in Shiraz, Southern Iran, 200 subjects diagnosed with lymphoma according to the World Health Organization (WHO) classification were enrolled. Controls (n=200) were frequency matched to the cases by sex, age, and center. Subjects who were a farmer were compared with all other occupations.

RESULTS

Out of the 200 cases that were diagnosed as lymphoid neoplasms, 100 were non-Hodgkin's lymphoma, 54 Hodgkin's lymphoma and 46 multiple myeloma. Seventy two percent of the NHL's were of the B-cell type, 15% of the T-cell type and the rest were not classified. Furthermore, subjects exposed to pesticides were at an increased risk of non-Hodgkin lymphoma and MM, but not Hodgkin lymphoma.

CONCLUSION

Risk of non-Hodgkin lymphoma and MM was highest for exposure to pesticides, among them, insecticide's risk was confirmed.

Pesticide use, immunologic conditions, and risk of non-Hodgkin lymphoma in Canadian men in six provinces

Pesticide exposures and immune suppression have been independently associated with the risk of non-Hodgkin lymphoma (NHL), but their joint effect has not been well explored. Data from a case-control study of men from six Canadian provinces were used to evaluate the potential effect modification of asthma, allergies, or asthma and allergies and hay fever combined on NHL risk from use of: (i) any pesticide; (ii) any organochlorine insecticide; (iii) any organophosphate insecticide; (iv) any phenoxy herbicide; (v) selected individual pesticides [1,1'-(2,2,2-trichloroethylidene)bis[4-chlorobenzene]; 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT), malathion, (4-chloro-2-methylphenoxy)acetic acid (MCPA), mecoprop, and (2,4-dichlorophenoxy)acetic acid (2,4-D); and (vi) from the number of potentially carcinogenic pesticides. Incident NHL cases (n = 513) diagnosed between 1991 and 1994 were recruited from provincial cancer registries and hospitalization records and compared to 1,506 controls. A stratified analysis was conducted to calculate odds ratios (ORs) adjusted for age, province, proxy respondent, and diesel oil exposure. Subjects with asthma, allergies, or hay fever had non-significantly elevated risks of NHL associated with use of MCPA (OR = 2.67, 95% confidence interval [CI]: 0.90-7.93) compared to subjects without any of these conditions (OR = 0.81, 95% CI: 0.39-1.70). Conversely, those with asthma, allergies, or hay fever who reported use of malathion had lower risks of NHL (OR = 1.25, 95% CI: 0.69-2.26) versus subjects with none of these conditions (OR = 2.44, 95% CI: 1.65-3.61). Similar effects were observed for asthma and allergies evaluated individually. Although there were some leads regarding effect modification by these immunologic conditions on the association between pesticide use and NHL, small numbers, measurement error and possible recall bias limit interpretation of these results.

Diabetes and non-Hodgkin's lymphoma: analyses of prevalence and annual incidence in 2005 using the National Health Insurance database in Taiwan

BACKGROUND

The association between diabetes and non-Hodgkin's lymphoma (NHL) is rarely studied and the risk associated with insulin use is not known.

MATERIALS AND METHODS

The crude and age-standardized trends of NHL incidence in the general population from 1979 to 2007 were first calculated. NHL prevalence and annual incidence in 2005 were calculated in 329,198 insurants aged≥45 years from a random sample of 1,000,000 insurants of the National Health Insurance. The risk factors were evaluated using logistic regression.

RESULTS

NHL incidence trends increased significantly in either sex. A total of 1079 and 148 NHL cases were identified for prevalence and incidence analyses, respectively. The respective prevalence (per 100,000) for diabetic and nondiabetic subjects was 480.2 and 269.9 (P<0.01), and the respective incidence (per 100,000) was 70.9 and 35.3 (P<0.01). Odds ratio for diabetic versus nondiabetic subjects after adjustment for age, sex, occupation, and living region was 1.51 (95% confidence interval 1.33-1.71) for prevalence and 1.48 (1.06-2.06) for incidence. In diabetic patients, the adjusted odds ratio for insulin users versus nonusers was 1.63 (1.23-2.15) for prevalence and 2.52 (1.37-4.64) for incidence.

CONCLUSIONS

NHL incidence is increasing in Taiwan. Diabetes and insulin use are associated with a higher risk.

The effect of lentivirus-mediated expression of tumor necrosis factor related apoptosis-inducing ligand and shRNA against Bcl-2 on the growth of lymphoma cells

It has been well established that tumor necrosis factor related apoptosis-inducing ligand (TRAIL) effectively induces apoptosis in tumor cells. However, tumor resistance to TRAIL, especially of hematological tumor cells, has become a major problem in the potential use of TRAIL in clinical practice. Among many factors that contribute to TRAIL resistance, overexpression of Bcl-2 is commonly seen in many kinds of tumors, particularly in lymphoma. In this study, we developed a lentivirus system that encodes recombinant human TRAIL cDNA for overexpression and Bcl-2 shRNA for down-regulation of Bcl-2 (lenti-TRAIL-shBcl-2) simultaneously. The efficiency of recombinant lentiviruses infecting different lymphoma cell lines was assessed by flow cytometric analysis and fluorescence microscopy. Reverse transcription polymerase chain reaction and Western blot assay were carried out to evaluate the expression of TRAIL and Bcl-2 in lymphoma cells after infection. We also examined the growth inhibition effect of recombinant lentivirus on lymphoma cell proliferation by CCK-8 (Cell Counting Kit-8) assay and its effect on bystander cells by flow cytometric analysis. The results showed that lymphoma cells were effectively infected by recombinant lentivirus and that TRAIL was exogenously expressed and Bcl-2 expression was down-regulated in lymphoma cells simultaneously. Results of this study demonstrated that lenti-TRAIL-shBcl-2 induced apoptosis in bystander cells as well as infected lymphoma cells and inhibited the growth of lymphoma cells.

Age-period-cohort modelling of non-Hodgkin's lymphoma incidence in a French region: a period effect compatible with an environmental exposure

BACKGROUND

The incidence of non-Hodgkin's lymphoma (NHL) has risen steadily during the last few decades in all geographic regions covered by cancer registration for reasons that remain unknown. The aims of this study were to assess the relative contributions of age, period and cohort effects to NHL incidence patterns and therefore to provide clues to explain the increasing incidence.

METHODS

Population and NHL incidence data were provided for the Doubs region (France) during the 1980-2005 period. NHL counts and person-years were tabulated into one-year classes by age (from 20 to 89) and calendar time period. Age-period-cohort models with parametric smooth functions (natural splines) were fitted to the data by assuming a Poisson distribution for the observed number of NHL cases.

RESULTS

The age-standardised incidence rate increased from 4.7 in 1980 to 11.9 per 100,000 person-years at risk in 1992 (corresponding to a 2.5-fold increase) and stabilised afterwards (11.1 per 100,000 in 2005). Age effects showed a steadily increasing slope up to the age of 80 and levelled off for older ages. Large period curvature effects, both adjusted for cohort effects and non-adjusted (p < 10-4 and p < 10-5, respectively), showed departure from linear periodic trends; period effects jumped markedly in 1983 and stabilised in 1992 after a 2.4-fold increase (compared to the 1980 period). In both the age-period-cohort model and the age-cohort model, cohort curvature effects were not statistically significant (p = 0.46 and p = 0.08, respectively).

CONCLUSIONS

The increased NHL incidence in the Doubs region is mostly dependent on factors associated with age and calendar periods instead of cohorts. We found evidence for a levelling off in both incidence rates and period effects beginning in 1992. It is unlikely that the changes in classification (which occurred after 1995) and the improvements of diagnostic accuracy could largely account for the 1983-1992 period-effect increase, giving way to an increased exposure to widely distributed risk factors including persistent organic pollutants and pesticides. Continued NHL incidence and careful analysis of period effects are of utmost importance to elucidate the enigmatic epidemiology of NHL.

Tanzanian malignant lymphomas: WHO classification, presentation, ploidy, proliferation and HIV/EBV association

BACKGROUND

In Tanzania, the International Working Formulation [WF] rather than the WHO Classification is still being used in diagnosing malignant lymphomas (ML) and the biological characterization including the HIV/EBV association is sketchy, thus restraining comparison, prognostication and application of established therapeutic protocols.

METHODS

Archival, diagnostic ML biopsies (N = 336), available sera (N = 35) screened by ELISA for HIV antibodies and corresponding clinical/histological reports at Muhimbili National Hospital (MNH) in Tanzania between 1996 and 2006 were retrieved and evaluated. A fraction (N = 174) were analyzed by histopathology and immunohistochemistry (IHC). Selected biopsies were characterized by flow-cytometry (FC) for DNA ploidy (N = 60) and some by in-situ hybridization (ISH) for EBV-encoded RNA (EBER, N = 37).

RESULTS

A third (38.8%, 109/281) of the ML patients with available clinical information had extranodal disease presentation. A total of 158 out of 174 biopsies selected for immunophenotyping were confirmed to be ML which were mostly (84. 8%, 134/158) non-Hodgkin lymphoma (NHL). Most (83.6%, 112/134) of NHL were B-cell lymphomas (BCL) (CD20+), of which 50.9%, (57/112) were diffuse large B-cell (DLBCL). Out of the 158 confirmed MLs, 22 (13.9%) were T-cell [CD3+] lymphomas (TCL) and 24 (15.2%) were Hodgkin lymphomas (HL) [CD30+]. Furthermore, out of the 60 FC analyzed ML cases, 27 (M:F ratio 2:1) were DLBCL, a slight majority (55.6%, 15/27) with activated B-cell like (ABC) and 45% (12/27) with germinal center B-cell like (GCB) immunophenotype. Overall, 40% (24/60) ML were aneuploid mostly (63.0%, 17/27) the DLBCL and TCL (54.5%, 6/11). DNA index (DI) of FC-analyzed ML ranged from 1.103-2.407 (median = 1.51) and most (75.0%) aneuploid cases showed high (>40%) cell proliferation by Ki-67 reactivity. The majority (51.4%, 19/37) of EBER ISH analyzed lymphoma biopsies were positive. Of the serologically tested MLs, 40.0% (14/35) were HIV positive, mostly with high (> or =40.0%) Ki-67 reactivity.

CONCLUSIONS

According to the 2001 WHO Classification, most subtypes are represented in Tanzanian ML. Extranodal presentation was common among MNH lymphoma patients who also showed high aneuploidy, tumor proliferation (KI-67) and EBER positivity. DLBCL was frequent and phenotype heterogeneity appeared similar to observations in Western countries suggesting applicability of established intervention approaches. HIV was apparently associated with high ML cell proliferation but extended studies are needed to clarify this.

Solvent exposure and non-Hodgkin lymphoma: no risk in a population-based study in the San Francisco Bay Area

The literature on environmental exposures and risk of non-Hodgkin lymphoma (NHL) is inconsistent and no occupational exposures have been conclusively identified as causal factors. We used job exposure matrices to assess the association between occupational exposure to solvents in a population-based case-control study of NHL (n = 1,591 cases; n = 2,515 controls) in the San Francisco Bay Area between 1988 and 1995. Occupational histories were collected during in-person interviews and were coded according to the 1980 U.S. Department of Commerce Alphabetic Index of Industries and Occupations. Odds ratios and 95% confidence intervals were adjusted for potential confounders. Our results have provided no support for an association between NHL and occupational exposure to solvents.

Vitamin D and non-Hodgkin lymphoma risk in adults: a review

Animal and human studies support a protective effect of vitamin D sufficiency related to malignancy by uncovering paracrine and autocrine effects of extra-renal 25-hydroxyvitamin D (25(OH)D) activation including regulation of cell cycle proliferation, apoptosis induction, and increased cell differentiation signaling. Recent epidemiologic studies demonstrate a reduction in non-Hodgkin lymphoma (NHL) risk with increased sunlight exposure. As sunlight is a major vitamin D source, it has been suggested that vitamin D status may mediate this observed association. This review provides a comprehensive discussion of the current epidemiologic evidence with regard to the investigation of an association between vitamin D status and NHL risk.

Is there truly a risk of lymphoma from biologic therapies?

The treatment of psoriasis has undergone a revolution with the advent of biologic therapies, including infliximab, etanercept, adalimumab, efalizumab, and alefacept. Biologics are generally safe and well tolerated. However, there has been concern over the risk of lymphoma with use of these agents because of their immunosuppressive properties. This review summarizes the current evidence in regards to lymphoma risk with biologic therapy obtained from case reports and case series, observational studies, clinical trials, and meta-analyses. The majority of data for T-cell inhibitors comes from case reports and relatively small, short-term clinical trials. In addition to published case reports and case series, TNF-alpha inhibitors have also been studied extensively in large cohort studies and meta-analyses of clinical trials derived primarily from the rheumatoid arthritis population. Current data are neither sufficient to completely rule out an increased risk of lymphoma associated with biologics, nor to firmly establish a causal relationship between biologics and lymphoma. Short- to intermediate-term treatment with biologics (e.g., up to 4 years) appears to be very safe with respect to lymphoma risk, especially with TNF-alpha inhibitors in which their potential risks appear to be well defined. Continued vigilance is warranted; however, in the appropriate patient, the risk-to-benefit profile of psoriasis treatment with respect to lymphoma risk appears highly favorable.

Type 2 diabetes mellitus and risk of non-Hodgkin lymphoma: a systematic review and meta-analysis

Type 2 diabetes mellitus is associated with altered immune function and chronic inflammation. Both of these immune conditions are implicated in the pathogenesis of non-Hodgkin lymphoma. The authors performed a systematic review to summarize findings from the current literature on the association between history of type 2 diabetes mellitus and risk of non-Hodgkin lymphoma. Ten case-control studies and three prospective cohort studies were included in this review. Meta-analysis found that a history of type 2 diabetes mellitus was positively associated with overall non-Hodgkin lymphoma risk. However, there was significant heterogeneity between studies. Study design was an important source of heterogeneity. The rate ratio between type 2 diabetes mellitus and non-Hodgkin lymphoma was found to be 1.18 (95% confidence interval: 0.99, 1.42) among case-control studies and 1.79 (95% confidence interval: 1.30, 2.47) among the prospective cohort studies. Weaknesses were identified in some of the included studies in the areas of case and control selection, measurement of covariates and non-Hodgkin lymphoma, and confounding control. Although a positive association between type 2 diabetes mellitus and risk of non-Hodgkin lymphoma was suggested, the evidence is inconclusive because of methodological limitations of the included case-control studies. More prospective studies with improved control of confounding are needed to confirm these findings.

Malignant lymphomas (ML) and HIV infection in Tanzania

Background

HIV infection is reported to be associated with some malignant lymphomas (ML) so called AIDS-related lymphomas (ARL), with an aggressive behavior and poor prognosis. The ML frequency, pathogenicity, clinical patterns and possible association with AIDS in Tanzania, are not well documented impeding the development of preventive and therapeutic strategies.

Methods

Sections of 176 archival formalin-fixed paraffin-embedded biopsies of ML patients at Muhimbili National Hospital (MNH)/Muhimbili University of Health and Allied Sciences (MUHAS), Tanzania from 1996–2001 were stained for hematoxylin and eosin and selected (70) cases for expression of pan-leucocytic (CD45), B-cell (CD20), T-cell (CD3), Hodgkin/RS cell (CD30), histiocyte (CD68) and proliferation (Ki-67) antigen markers. Corresponding clinical records were also evaluated. Available sera from 38 ML patients were screened (ELISA) for HIV antibodies.

Results

The proportion of ML out of all diagnosed tumors at MNH during the 6 year period was 4.2% (176/4200) comprising 77.84% non-Hodgkin (NHL) including 19.32% Burkitt's (BL) and 22.16% Hodgkin's disease (HD). The ML tumors frequency increased from 0.42% (1997) to 0.70% (2001) and 23.7% of tested sera from these patients were HIV positive. The mean age for all ML was 30, age-range 3–91 and peak age was 1–20 years. The male:female ratio was 1.8:1. Supra-diaphragmatic presentation was commonest and histological sub-types were mostly aggressive B-cell lymphomas however, no clear cases of primary effusion lymphoma (PEL) and primary central nervous system lymphoma (PCNSL) were diagnosed.

Conclusion

Malignant lymphomas apparently, increased significantly among diagnosed tumors at MNH between 1996 and 2001, predominantly among the young, HIV infected and AIDS patients. The frequent aggressive clinical and histological presentation as well as the dominant B-immunophenotype and the HIV serology indicate a pathogenic association with AIDS. Therefore, routine HIV screening of all malignant lymphoma patients at MNH is necessary to enable comprehensive ARL diagnosis and formulation of preventive and therapeutic protocols.

Comprehensive identification of proteins in Hodgkin lymphoma-derived Reed-Sternberg cells by LC-MS/MS

Mass spectrometry-based proteomics in conjunction with liquid chromatography and bioinformatics analysis provides a highly sensitive and high-throughput approach for the identification of proteins. Hodgkin lymphoma is a form of malignant lymphoma characterized by the proliferation of Reed-Sternberg cells and background reactive lymphocytes. Comprehensive analysis of proteins expressed and released by Reed-Sternberg cells would assist in the discovery of potential biomarkers and improve our understanding of its pathogenesis. The subcellular proteome of the three cellular compartments from L428 and KMH2 Hodgkin lymphoma-derived cell lines were fractionated, and analyzed by reverse-phase liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Additionally, proteins released by Hodgkin lymphoma-derived L428 cells were extracted from serum-free culture media and analyzed. Peptide spectra were analyzed using TurboSEQUEST against the UniProt protein database (5.26.05; 188 712 entries). A subset of the identified proteins was validated by Western blot analysis, immunofluorescence microscopy and immunohistochemistry. A total of 1945 proteins were identified with 785 from the cytosolic fraction, 305 from the membrane fraction, 441 from the nuclear fraction and 414 released proteins using a minimum of two peptide identifications per protein and an error rate of <5.0%. Identification of proteins from diverse functional groups reflected the functional complexity of the Reed-Sternberg proteome. Proteins with previously reported oncogenic function in other cancers and from signaling pathways implicated in Hodgkin lymphoma were identified. Selected proteins without previously demonstrated expression in Hodgkin lymphoma were validated by Western blot analysis (B-RAF, Erb-B3), immunofluorescence microscopy (Axin1, Tenascin-X, Mucin-2) and immunohistochemistry using a tissue microarray (BRAF, PIM1). This study represents the first comprehensive inventory of proteins expressed by Reed-Sternberg cells of Hodgkin lymphoma and demonstrates the utility of combining cellular subfractionation, protein precipitation, tandem mass spectrometry and bioinformatics analysis for comprehensive identification of proteins that may represent potential biomarkers of the disease.

The role of dietary factors in the epidemiology of non-Hodgkin's lymphoma

The incidence of non-Hodgkin's lymphoma (NHL) has risen dramatically over recent decades and, despite some known risk factors, such as compromised immunity, the etiology of NHL and the reasons for most of this increase are unknown. Dietary components may be a common and critical source of immunologic antigens and promoters, which needs to be incorporated more in the etiologic research of NHL. To date, epidemiologic evidence suggests that obesity and fat intake, in particular saturated or animal fat, may increase the risk of NHL; whereas whole-grains, vegetables and moderate consumption of alcohol may be inversely associated with NHL risk. Much of the current evidence is obtained from case-control studies, which are subject to dietary recall bias; therefore, this area of research requires further study within prospective cohorts with detailed dietary information and with a large number of cases to examine disease sub-type heterogeneity.

Malignant lymphomas in the elderly: A single institute experience highlights future directions

In this study, our experience with the diagnostics and treatment of malignant lymphoma patients were analyzed, with a special consideration of the elderly. Between 1980 and 2005, there were 181 cases found (35%) among 517 non-Hodgkin's lymphoma (NHL) patients and 46 cases (8.1%) among 565 Hodgkin's lymphoma (HL) patients, who were at least 65 years old at the time of diagnosis. Comparing elderly patients to young ones, the time from first symptoms to diagnosis was significantly longer (NHL: 7.6 months versus 4.1 months, HL: 11.4 months versus 5.6 months). B-cell and indolent NHL-s were more common (92.8% versus 79.2% and 56.4% versus 35.1%) such as classical lymphocyte predominant (cLP) HL-s (30.4% versus 15.0%); however nodular sclerosis (NS) HL-s occurred less frequently (10.9% versus 32.2%). Stages were more advanced and comorbidity was more common. Primary therapies were more often inappropriate (NHL: 20.4% versus 5.1%, HL: 26.0% versus 6.0%); there were more complications, but less cases with complete remission (NHL: 17.1% versus 61.1%, HL: 63.0% versus 79.2%) and dose reductions were more commonly applied (NHL: 46.7% versus 17.2%, HL: 52.9% versus 11.3%). Remission rates were significantly worsened by dose reductions (NHL: 68.5% versus 34.5%, HL: 61.8% versus 44.4%). Appropriate therapies resulted in significantly better overall survival (OS) rates (log-rank<0.05). It can be concluded that more favourable results can be achieved in the remission and survival rates of elderly malignant lymphoma patients if the appropriate curative or palliative therapies, considering new and less toxic protocols such as supportive care, are chosen.

Cancer incidence patterns by region and socioeconomic deprivation in teenagers and young adults in England

Data on 35 291 individuals with cancer, aged 13–24 years, in England from 1979 to 2001 were analysed by region and socio-economic deprivation of census ward of residence, as measured by the Townsend deprivation index. The incidence of leukaemia, lymphoma, central nervous system tumours, soft tissue sarcomas, gonadal germ cell tumours, melanoma and carcinomas varied by region (P<0.01, all groups) but bone tumour incidence did not. Lymphomas, central nervous system tumours and gonadal germ cell tumours all had higher incidence in less deprived census wards (P<0.01), while chronic myeloid leukaemia and carcinoma of the cervix had higher incidence in more deprived wards (P<0.01). In the least deprived wards, melanoma incidence was nearly twice that in the most deprived, but this trend varied between regions (P<0.001). These cancer incidence patterns differ from those seen in both children and older adults and have implications for aetiology and prevention.

Solvent exposure and malignant lymphoma: a population-based case-control study in Germany

Aims

To analyze the relationship between exposure to chlorinated and aromatic organic solvents and malignant lymphoma in a multi-centre, population-based case-control study.

Methods

Male and female patients with malignant lymphoma (n = 710) between 18 and 80 years of age were prospectively recruited in six study regions in Germany (Ludwigshafen/Upper Palatinate, Heidelberg/Rhine-Neckar-County, Würzburg/Lower Frankonia, Hamburg, Bielefeld/Gütersloh, and Munich). For each newly recruited lymphoma case, a gender, region and age-matched (± 1 year of birth) population control was drawn from the population registers. In a structured personal interview, we elicited a complete occupational history, including every occupational period that lasted at least one year. On the basis of job task-specific supplementary questionnaires, a trained occupational physician assessed the exposure to chlorinated hydrocarbons (trichloroethylene, tetrachloroethylene, dichloromethane, carbon tetrachloride) and aromatic hydrocarbons (benzene, toluene, xylene, styrene). Odds ratios (OR) and 95% confidence intervals (CI) were calculated using conditional logistic regression analysis, adjusted for smoking (in pack years) and alcohol consumption. To increase the statistical power, patients with specific lymphoma subentities were additionally compared with the entire control group using unconditional logistic regression analysis.

Results

We observed a statistically significant association between high exposure to chlorinated hydrocarbons and malignant lymphoma (Odds ratio = 2.1; 95% confidence interval 1.1–4.3). In the analysis of lymphoma subentities, a pronounced risk elevation was found for follicular lymphoma and marginal zone lymphoma. When specific substances were considered, the association between trichloroethylene and malignant lymphoma was of borderline statistical significance. Aromatic hydrocarbons were not significantly associated with the lymphoma diagnosis.

Conclusion

In accordance with the literature, this data point to a potential etiologic role of chlorinated hydrocarbons (particularly trichloroethylene) and malignant lymphoma. Chlorinated hydrocarbons might affect specific lymphoma subentities differentially. Our study does not support a strong association between aromatic hydrocarbons (benzene, toluene, xylene, or styrene) and the diagnosis of a malignant lymphoma.

Sun exposure and malignant lymphoma: A population-based case–control study in Germany

Although some causes for malignant lymphoma are known their etiology is not well understood so far. We analyze the relationship between sun exposure and malignant lymphoma in a multicenter, population-based case-control study. Patients with malignant lymphoma (n = 710, 18-80 years) were prospectively recruited in 6 study regions in Germany. For each case, a gender, region and age-matched control was drawn from population-registers. In personal interviews, lifetime holidays spent in sunny climate, outdoor leisure activities and sunbed or sunlamp use were recorded. On basis of job task-specific supplementary questionnaires, an occupational physician assessed the cumulative working time outside. Odds ratios (OR) and 95%-confidence-intervals (CI) were calculated using conditional logistic regression analysis, adjusted for smoking and alcohol consumption. To increase statistical power, patients with specific lymphoma subentities were additionally compared with the entire control group using unconditional logistic regression. We observed a reduced overall lymphoma risk among subjects having spent vacations at sunny climates or frequently used sunbeds or sunlamps. The analysis of lymphoma subentities revealed similar results with the exception of T-NHL and follicular lymphoma which were positively associated with outdoor leisure activities. While cumulative working time outside appeared unrelated to NHL overall and most subentities, it was negatively associated with follicular lymphoma and weakly positively to HL. This data suggest that exposure to natural and artificial ultraviolet radiation may reduce the OR for lymphoma in this study population.

Epidemiology and etiology of non-Hodgkin lymphoma--a review

The etiology of non-Hodgkin lymphoma, as well as its global dramatic rise in incidence during the past decades, remains largely unexplained. However, there is increasing awareness that this group of malignancies may entail not only clinical, morphological and molecular heterogeneity, but also considerable variations in terms of etiologic factors. In this review, epidemiologic patterns are summarized as well as current evidence of associations between various known or suspected risk factors for non-Hodgkin lymphoma overall or for any of its subtypes. Central pathogenetic mechanisms include immunosuppression, especially in relation to T-cell function and loss of control of latent EBV infection, and chronic antigen stimulation. Some degree of familiar aggregation also implies a role for genetic susceptibility. A number of recent investigations of non-Hodgkin lymphoma etiology will hopefully lead to a better understanding of the causes of these malignancies.

Gene polymorphisms in Toll-like receptors, interleukin-10, and interleukin-10 receptor alpha and lymphoma risk

Interactions between environment and immune system play an essential role in the aetiology of immunopathologies, including lymphomas. Toll-like receptors (TLR) belong to a group of pattern recognition receptors, with importance for innate immune response and inflammatory processes. Interleukin-10 (IL-10) is a key regulatory cytokine and has been implicated in lymphomagenesis. Functional polymorphisms in these inflammation-associated genes may affect the susceptibility towards lymphoma. To test this hypothesis, we have genotyped DNA of 710 lymphoma cases and 710 controls within the context of a population-based epidemiological study for 11 functionally important single-nucleotide polymorphisms in TLR1, -2, -4, -5, -9, IL10 and IL10 receptor (IL10RA). The IL10RA Ser138Gly variant was underrepresented among lymphoma cases (odds ratio (OR)=0.81, 95 per cent confidence interval (95% CI)=0.65-1.02), mainly owing to an inverse association with Hodgkin's lymphoma (HL). The TLR2 -16933T>A variant was associated with a 2.8-fold increased risk of follicular lymphoma (95% CI=1.43-5.59) and a decreased risk of chronic lymphocytic leukaemia (OR=0.61, 95% CI=0.38-0.95). Furthermore, the TLR4 Asp299Gly variant was positively associated with the risk of mucosa-associated lymphoid tissue lymphoma (OR=2.76, 95% CI=1.12-6.81) and HL (OR=1.80, 95% CI=0.99-3.26). In conclusion, this study suggests an effect of polymorphisms in factors of the innate immune response in the aetiology of some lymphoma subtypes.