Chlamydia psittaci is variably associated with ocular adnexal MALT lymphoma in different geographical regions

Chlamydophila psittaci eradication with doxycycline as first-line targeted therapy for ocular adnexae lymphoma: final results of an international phase II trial

PURPOSE

The pathogenic association between Chlamydophila psittaci (Cp) and ocular adnexal marginal zone lymphoma (OAMZL) and the efficacy of doxycycline monotherapy have been investigated in retrospective series with variations in stage, management, and follow-up duration. To our knowledge, this is the first international phase II trial aimed at clarifying Cp prevalence and activity of first-line doxycycline in a homogeneous series of consecutive patients with newly diagnosed stage I OAMZL.

PATIENTS AND METHODS

Forty-seven patients were registered. Tumor tissue, conjunctival swabs, and peripheral blood from 44 patients were assessed for seven Chlamydiaceae infections by three polymerase chain reaction protocols. Thirty-four patients with measurable or parametrable disease were treated with doxycycline and assessed for chlamydial eradication and lymphoma response (primary end point).

RESULTS

Cp DNA was detected in biopsies of 39 patients (89%); no other Chlamydiaceae were detected. Twenty-nine patients had Cp DNA in baseline swabs and/or blood samples and were evaluable for chlamydial eradication, which was achieved in 14 patients (48%). Lymphoma regression was complete in six patients and partial in 16 (overall response rate, 65%; 95% CI, 49% to 81%); 11 had stable disease, and one had progressive disease. At a median follow-up of 37 months (range, 15 to 62 months), 20 patients remained relapse free (5-year progression-free survival [PFS] ± standard deviation, 55% ± 9%). Cp eradication was associated with improved response rate (86% v 47%; P = .02) and 5-year PFS (68% v 47%; P = .11).

CONCLUSION

Upfront doxycycline is a rational and active treatment for patients with stage I Cp-positive OAMZL. Lymphoma regression is consequent to Cp eradication, which can easily be monitored on conjunctival and blood samples. Prospective trials aimed at identifying more effective administration schedules for doxycycline are warranted.

Lack of association of conjunctival MALT lymphoma with Chlamydiae or Helicobacter pylori in a cohort of Chinese patients

BACKGROUND

This study was conducted to detect microbial pathogens in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma specimens in an attempt to determine possible associations between conjunctival MALT lymphoma and microbial infections.

MATERIAL/METHODS

Using PCR technique, freshly obtained tumor specimens from 16 cases of conjunctival MALT lymphoma, as confirmed by postoperative pathology, were analyzed for DNA of Chlamydia psittaci (C. psittaci), Chlamydia trachomatis (C. trachomatis), Chlamydia pneumoniae (C. pneumoniae) and Helicobacter pylori (H. pylori). Synthetic C. psittaci, C. trachomatis, C. pneumoniae and H. pylori DNA were used as positive control, and blank plasmid DNA as negative control.

RESULTS

Electrophoresis showed that no bands corresponding to the positive control were observed in the specimens, indicating that no DNA of the 4 microorganisms was detected in the specimens of the 16 cases of conjunctival MALT lymphoma.

CONCLUSIONS

The PCR technique was able to detect the positive control quickly and accurately, but the results of PCR in analyzing the 16 specimens were negative, indicating that there is no association between conjunctival MALT lymphoma and the 4 microorganisms in Chinese patients.

IgG4-related systemic sclerosing disease of the ocular adnexa: a potential mimic of ocular lymphoma

IgG4-related sclerosing disease has been described in the orbit and ocular adnexa. Of 164 biopsies of the ocular region for suspected lymphoma, we identified 6 cases of IgG4 disease, 4 of which were previously unrecognized. All 6 cases demonstrated increased plasma cells in a background of sclerosis and increased absolute numbers of IgG4-expressing cells. Our results confirm the difficulty in diagnosing IgG4-related sclerosing disease in the ocular region. Based on the findings, we suggest that specimens from biopsies of the eye and ocular adnexa for which a definitive diagnosis of lymphoma is not established undergo further workup for IgG and IgG4, particularly if increased plasma cells and sclerosis are present. When IgG4-expressing plasma cells account for greater than 50% of IgG-expressing plasma cells, a diagnosis of IgG4 disease should be considered. Timely recognition would benefit patients by allowing appropriate management with corticosteroid therapy and avoiding more aggressive or unnecessary therapeutic options.

Chlamydia psittaci in ocular adnexa MALT lymphoma: a possible role in lymphomagenesis and a different geographical distribution

Ocular adnexa MALT-lymphomas represent approximatively 5-15% of all extranodal lymphomas. Almost 75% of OAMLs are localized in orbital fat, while 25% of cases involves conjunctive. MALT-lymphomas often recognize specific environmental factors responsible of lymphoma development and progression. In particular as Helicobacter pylori in gastric MALT lymphomas, other bacterial infections have been recognized related to MALT lymphomas in specific site. Recently Chlamydia psittaci has been identified in Ocular Adnexa MALT lymphomas, with variable frequence dependently from geographic areas. Thus bacterial infection is responsible of clonal selection on induced MALT with subsequent lymphoma development. Moreover Chlamydia psittaci could promote chromosomal aberration either through genetic instability as a consequence of induced proliferation and probably through DNA oxidative damage. The most common translocation described in MALT lymphomas affects NF-kB pathway with a substantial antiapoptotic effect. Several therapeutic approaches are now available, but the use of antibiotic-therapy in specific cases, although with conflicting results, could improve the treatment of ocular adnexa MALT lymphomas. In this review we analyse the most relevant features of Ocular adnexa MALT lymphomas, underlining specific biological characteristics mainly related to the potential role of Chlamydia psittaci in lymphomagenesis.

Intralesional interferon-α for conjunctival mucosa-associated lymphoid tissue lymphoma: long-term results

OBJECTIVE

To report the long-term therapeutic results for patients with conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma who were treated with intralesional injections of interferon-α (IFN-α).

DESIGN

Prospective, nonrandomized, interventional case series.

PARTICIPANTS

Twenty eyes of 16 patients with histologically proven conjunctival MALT lymphoma in the absence of systemic disease.

METHODS

Patients were given 1,500,000 international units (IU) of IFN-α (Roferon-A; Roche s.p.a., Milano, Italy) subconjunctivally inside the lesion 3 times weekly for 4 weeks. If there was even a minimal response, a further cycle of 1,000,000 IU 3 times weekly for 4 weeks was administered.

MAIN OUTCOME MEASURES

Patients were followed up clinically using slit-lamp examination to determine evidence of tumor disappearance or recurrence. In 10 eyes, an incisional biopsy was performed 6 months after therapy to verify the histologic absence of the lesion.

RESULTS

A complete response was obtained in 15 eyes (75%) at the end of first cycle treatment, and in 5 eyes (25%) after further cycles. Seventeen eyes (85%) showed no local recurrence after a median follow-up of 65 months (range, 15-136 months). Three eyes (15%) demonstrated recurrence at variable points after treatment. One patient with stage IIA lymphoma exhibited systemic lymphoma progression.

CONCLUSIONS

Local immunotherapy with IFN-α seems to be an effective and lasting treatment method and provides an alternative to radiotherapy for conjunctival MALT lymphomas. Very few transient side effects were detected.

Biased use of the IGHV4 family and evidence for antigen selection in Chlamydophila psittaci-negative ocular adnexal extranodal marginal zone lymphomas

Extranodal marginal zone lymphomas (EMZL) are the most common lymphomas in the ocular adnexa. The etiology and potential role for antigenic stimulation in these lymphomas are still controversial. We have examined IGHV gene usage and mutations in 67 Chlamydophila psittaci-negative ocular adnexal EMZL. Clonal IGHV gene sequences were identified in 43 tumors originating from the orbit (19), conjunctivae (18) and lacrimal gland (6). Forty four potentially functional clonal IGHV gene sequences were detected with overrepresentation of the IGHV4 family and IGHV4-34 gene. All but 3 sequences were mutated with the average percent homology to the germ line of 93.5±6.1. Multinomial model and Focused binomial test demonstrated evidence for positive and/or negative antigen selection in 59% of the potentially functional IGHV genes. Intraclonal variation was detected in 8 of 11 tumor specimens. Overall our findings demonstrate that C. psittaci-negative ocular adnexal EMZL exhibit biased usage of IGHV families and genes with evidence for intraclonal heterogeneity and antigen selection in multiple tumors, implicating B-cell receptor-mediated antigen stimulation in the pathogenesis of these lymphomas.

A Role for RNA Viruses in the Pathogenesis of Burkitt's Lymphoma: The Need for Reappraisal

Certain infectious agents are associated with lymphomas, but the strength of the association varies geographically, suggesting that local environmental factors make important contributions to lymphomagenesis. Endemic Burkitt's Lymphoma has well-defined environmental requirements making it particularly suitable for research into local environmental factors. The Epstein-Barr virus and holoendemic Malaria are recognized as important cofactors in endemic Burkitt's Lymphoma and their contributions are discussed. Additionally, infection with Chikungunya Fever, a potentially oncogenic arbovirus, was associated with the onset of endemic Burkitt's Lymphoma in one study and also with space-time case clusters of the lymphoma. Chikungunya Virus has several characteristics typical of oncogenic viruses. The Flavivirus, Hepatitis C, a Class 1 Human Carcinogen, closely related to the arboviruses, Yellow Fever, and Dengue, is also more distantly related to Chikungunya Virus. The mechanisms of oncogenesis believed to operate in Hepatitis C lymphomagenesis are discussed, as is their potential applicability to Chikungunya Virus.

Infectious agents and lymphoma

In the past 25 years revelations on the genesis of human cancer have come at an increasing pace. Research on oncogenic infectious agents, especially viruses, has helped us to understand the process of malignant transformation of cells because the cellular events in viral-driven transformation mirror, often brilliantly, basic cellular processes that culminate in cancer, even those not associated with viruses. Infectious agents, especially viruses, account for several of the most common malignancies-up to 20% of all cancers. Some of these cancers are endemic, with a high incidence in certain geographic locations, but sporadic/lower incidence in other parts of the world. Lymphomas arise frequently in association with infectious agents such as Epstein-Barr virus, human immunodeficiency virus, human herpes virus 8, Helicobacter pylori, and hepatitis C virus. In this review, we will focus on the association between infectious agents and lymphomas, with a look at the molecular mechanisms they use to disturb cell regulation and eventually result in cancer.

Clinical significance of tumor-infiltrating FOXP3+ T cells in patients with ocular adnexal mucosa-associated lymphoid tissue lymphoma

We evaluated the association between tumor-infiltrating FOXP3+ T cells and clinical outcomes in patients with ocular adnexal lymphoma of mucosa-associated lymphoid tissue type (OAML). Pretreatment formalin-fixed paraffin-embedded tissues from 42 patients with OAML were stained with 236A/E7 anti-FOXP3 murine monoclonal antibody as well as CD3, CD4 and CD8 antibodies. The amount of FOXP3+ T cells was numerically quantified using an image analysis program. Front-line treatments were as follows: combination chemotherapy (n = 25); radiotherapy (n = 9); doxycycline (n = 6); and wait and see (n = 2). Complete response (CR) was observed in 20 (50%) of 40 evaluable patients. Median progression-free survival (PFS) was 50 months. A high number of FOXP3+ T cells (n = 21, ≥ 180/0.58 mm(2)) showed a higher CR rate (33%vs 71%, P = 0.013) and tendency towards prolonged PFS (48 vs 67 months, P = 0.110). In the combination chemotherapy group, a high number of FOXP3+ T cells was significantly associated with a higher CR rate (29%vs 82%, P = 0.008) and prolonged PFS (17 vs 79 months, P = 0.003). A high number of tumor-infiltrating FOXP3+ T cells correlates with a favorable clinical outcome in OAML patients.

Chlamydia psittaci Infection in nongastrointestinal extranodal MALT lymphomas and their precursor lesions

Extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT) are associated with various infectious pathogens. We analyzed the presence of Chlamydia psittaci, Chlamydia pneumoniae, and Chlamydia trachomatis DNA in 47 nongastrointestinal and 14 gastrointestinal MALT lymphomas, 37 nonmalignant control samples, and 27 autoimmune precursor lesions by polymerase chain reaction amplification and direct sequencing. In 47 nongastrointestinal MALT lymphomas, 13 (28%) were positive for C psittaci DNA compared with 4 (11%) of 37 nonmalignant control samples (P = .09). C psittaci was detected at variable frequencies in MALT lymphomas of different sites: lung, 100% (5/5; P < .01); thyroid gland, 30% (3/10; P > .05); salivary gland, 13% (2/15; P > .05); ocular adnexa, 15% (2/13); and skin, 25% (1/4). Of 27 autoimmune precursor lesions (11 Hashimoto thyroiditis and 16 Sjögren syndrome), 11 (41%) contained C psittaci DNA. Only 1 (7%) of 14 gastrointestinal MALT lymphomas was positive for C psittaci. All specimens were negative for C trachomatis and C pneumoniae. Besides ocular adnexal lymphomas, C psittaci infection is associated with nongastrointestinal MALT lymphomas and autoimmune precursor lesions, suggesting possible involvement of C psittaci-induced antigenic-driven MALT lymphomagenesis.

Role of bacteria in oncogenesis

Although scientific knowledge in viral oncology has exploded in the 20th century, the role of bacteria as mediators of oncogenesis has been less well elucidated. Understanding bacterial carcinogenesis has become increasingly important as a possible means of cancer prevention. This review summarizes clinical, epidemiological, and experimental evidence as well as possible mechanisms of bacterial induction of or protection from malignancy.

Ocular adnexal mucosa-associated lymphoid tissue lymphoma in Northern China: high frequency of numerical chromosomal changes and no evidence of an association with Chlamydia psittaci

Studies from different countries showed variations of genetic changes and association with Chlamydia psittaci in ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma. A total of 38 ocular adnexal MALT lymphoma cases from Northern China were studied. Genetic abnormalities were investigated in 28 cases by interphase FISH. C. psittaci and other infectious agents that are commonly-associated with chronic eye disease were screened in 38 cases by PCR. Genetic abnormalities were detected in 60.7% of cases. Among them, only one showed a break-apart of the IgH gene and all others showed numerical abnormalities, including trisomy 18 in 7 cases (25%), 3 copies of BCL6 gene in 12 cases (43%), and 3 copies of C-MYC gene in 2 cases (7%). C. pneumoniae was positive in two cases (5.3%), and C. psittaci, C. trachomatis, HSV1, HSV2, ADV8, and ADV19 were not detected in any cases. In conclusion, numerical abnormalities are frequent and the chromosomal translocations commonly associated with MALT lymphomas are rare in ocular adnexal MALT lymphoma of Northern China. C. psittaci and other infectious agents are not associated with ocular adnexal MALT lymphoma in these patients.

Ocular adnexal lymphomas: a review

Ocular adnexal lymphomas comprise 1% to 2% of all non-Hodgkin lymphomas and about 8% of extranodal lymphomas. They are a heterogeneous group of malignancies, the majority of which are primary extranodal lymphoma with most (up to 80%) of the marginal zone of mucosa associated lymphoid tissue type (MALT lymphoma). This review will encompass the incidence, histology, immunophenotyping, recent advances in molecular and cytogenetics, clinical features including outcome, and prognostic factors. The association with Chlamydia psittaci and the very recently recognized occurrence in the context of IgG4-related sclerosing disease will be discussed. Finally, traditional (surgery, radiotherapy, chemotherapy) and newer forms of therapy (immunotherapy and radioimmunotherapy) will be reviewed.

First-line therapy with doxycycline in ocular adnexal mucosa-associated lymphoid tissue lymphoma: a retrospective analysis of clinical predictors

This retrospective study was launched to evaluate the efficacy of doxycycline and to find independent predictors of a clinical response in patients with ocular adnexal lymphoma of mucosa-associated lymphoid tissue (OAML). Thirty-eight patients with newly diagnosed, localized OAML received doxycycline for 3 weeks (12 patients) or 6 weeks (26 patients). Clinical factors including absolute lymphocyte count (ALC) and neutrophil count (ANC) were compared between responders and non-responders. After a median follow-up of 26.4 months, doxycycline resulted in an overall response rate of 47% and a 3-year time-to-treatment failure (TTF) rate of 84%. Patients treated with doxycycline for 6 weeks versus 3 weeks tended to have a higher response rate (54%vs 33%). Absolute lymphocytosis (ALC > 3.01 x 10(9)/L) and absolute neutrophilia (ANC > 1.92 x 10(9)/L) were defined based on the median value of each count. Patients with (19 patients) versus without absolute lymphocytosis had significantly shorter 2-year TTF (70%vs 100%, P = 0.021) and a lower response rate (32%vs 63%, P = 0.051). Absolute lymphocytosis (odds ratio [OR] = 4.7; 95% confidence interval [CI], 1.1-20.8; P = 0.043) and non-conjunctival tumor (OR = 11.8; 95% CI, 1.1-122.5; P = 0.038) were negative predictors for response by multivariate analysis. Front-line doxycycline is effective particularly in localized OAML patients without absolute lymphocytosis but with conjunctival involvement.

Geographic variation and environmental conditions as cofactors in Chlamydia psittaci association with ocular adnexal lymphomas: a comparison between Italian and African samples

A particular extra-nodal lymphoma type arises from B cells of the marginal zone (MZ) of mucosa-associated lymphoid tissue (MALT). The aetiology of MZ lymphomas suggests that they are associated with chronic antigenic stimulation by microbial pathogens, among which Helicobacter pylori-associated gastric MALT lymphoma is the best studied. Recently, MALT lymphomas have been described in the context of chronic conjunctivitis, which can be associated with Chlamydia spp. infection. Studies from Italy showed the presence of Chlamydia psittaci in 87% of ocular adnexal lymphomas (OAL), and C. psittaci has been described in a large part of samples from Austria and Korea as well. However, this finding was not always confirmed by other studies, suggesting that the association with C. psittaci may depend on geographic heterogeneity. Interestingly, none of the studies up to now has been carried out in the African population, where a strong association between infectious agents and the occurrence of human neoplasms has been reported. This study was designed to investigate the possible association of Chlamydia psittaci in cases retrieved from Kenya, compared to cases from Italy. Our results showed that there was a marked variation between the two geographical areas in terms of association with C. psittaci, as 17% (5/30) of the samples from Italy were positive for C. psittaci, whereas no association with this pathogen was observed in any of the African samples (0/9), suggesting that other cofactors may determine the OAL occurrence in those areas. OAL cases are often characterized by down-regulation of p16/INK4a expression and promoter hypermethylation of the p16/INK4a gene. Our results showed a partial methylation of p16/INK4a promoter in C. psittaci-negative cases, whereas no hypermethylation of this gene was found in C. psittaci-positive cases, suggesting that mechanisms other than promoter hypermethylation lead to p16/INK4a silencing in C. psittaci-positive cases. We may conclude that the role of epidemiologic, environmental and genetic factors, must be considered in the aetiology of this disease.

Treatment options for ocular adnexal lymphoma (OAL)

Most lymphomas that involve the ocular adnexal structure are low grade, B cell, non-Hodgkin’s lymphomas. The treatment depends upon the grade and stage of the disease. High grade lymhoma requires treatment with systemic chemotherapy whereas the localized low grade (extranodal marginal zone lymphoma) can be successfully managed with local radiotherapy. Chlamydia psittaci infection is associated with low grade ocular lymphoma; however there is wide geographic variation in the strength of this association. Blanket antibiotic therapy is not advised unless there is proof of an infective agent. The monoclonal antibody, rituximab, may be successful for CD20 positive lymphoma, although it is likely that rituximab will have better long-term results when used in combination with systemic chemotherapy.

Chlamydial infection: the link with ocular adnexal lymphomas

Chlamydiae are obligate intracellular bacteria that grow in eukaryotic cells and cause a wide spectrum of diseases. They can establish persistent infections, are mitogenic in vitro, promote polyclonal cell proliferation in vivo and induce resistance to apoptosis in infected cells-properties that might contribute to tumorigenesis. In fact, Chlamydophila psittaci (Cp) has been linked to the development and maintenance of ocular adnexal marginal zone B-cell lymphoma (OAMZL). In this indolent malignancy, Cp is transported by monocytes and macrophages and causes both local and systemic infection. Cp elementary bodies are viable and infectious in the conjunctiva and peripheral blood of patients with OAMZL. Bacterial eradication with antibiotic therapy is often followed by lymphoma regression. Despite recent advances in the understanding of this bacterium-lymphoma association, several questions remain unanswered. For instance, prevalence variations among different geographical areas and related diagnostic and therapeutic implications remain a major investigational issue. We will focus on clinical and therapeutic implications of chlamydial infections in patients with lymphomas and summarize the current knowledge on the association between Cp infection and OAMZL. Available data on the epidemiology, biology and pathogenesis of this association are analyzed and new investigative and clinical approaches are discussed.

Zoonotic Chlamydophila psittaci infections from a clinical perspective

Human psittacosis is a zoonotic infectious disease which is caused by the obligate intracellular bacterium Chlamydophila psittaci. Transmission of the disease usually originates from close contact with infected birds, most frequently in the context of the poultry industry, and from contact with Psittaciformes (cockatoos, parrots, parakeets and lories). Due to a low awareness of the disease and a variable clinical presentation psittacosis is often not recognised as such by general practitioners. This review therefore gives an overview of the epidemiology, symptoms, diagnosis and possible treatments for psittacosis in humans. The current case definition for epidemiological surveillance, as issued by the CDC, is discussed, as well as the possible emergence of Cp. psittaci antibiotic-resistant strains. There is an urgent need for information and for awareness campaigns directed at professional health care workers and the general public. In addition, a broader use of new diagnostic methods in medical laboratories and the development of prophylactics are called for.

Chronic inflammatory disease, lymphoid tissue neogenesis and extranodal marginal zone B-cell lymphomas

Chronic autoimmune or pathogen-induced immune reactions resulting in lymphoid neogenesis are associated with development of malignant lymphomas, mostly extranodal marginal zone B-cell lymphomas (MZBCLs). In this review we address (i) chemokines and adhesion molecules involved in lymphoid neogenesis; (ii) the autoimmune diseases and pathogens which are associated with development of B-cell lymphomas; (iii) the molecular mechanisms involved in the initiation and progression of MZBCL; and (iv) 'potential' mouse models for MZBCL.

Low prevalence ofChlamydia psittaciin ocular adnexal lymphomas from Cuban patients

Most ocular adnexal lymphomas (OAL) are extranodal marginal zone B-cell lymphomas (EMZL) of mucosa-associated lymphoid tissue (MALT)-type. Chronic antigen stimulation has been suggested to have a pathogenetic role in EMZL and Chlamydia psittaci chronic infection has been recently associated with the development of OAL in a series of patients from Italy. To assess this association, an evaluation of the presence of C. psittaci was made in a different OAL population. DNA samples were obtained from formalin-fixed, paraffin-embedded sections samples of 26 patients with OAL, 20 non-OAL and 20 benign ocular lesions, diagnosed and treated between 1998 and 2003 at National Institute of Oncology in Havana, Cuba. All samples were histologically reviewed by an expert pathologist. Fluorescence in situ hybrization (FISH) analysis of translocations involving MALT1 was performed. The presence of bacterial DNA was assessed with a multiplex touchdown enzyme time release polymerase chain reaction. DNA sequencing was performed to confirm suspicious bands. Seventy-three percent of the OAL cases were EMZL and 81% were in stage IE. FISH analysis was performed in 13 OAL cases and none of them evidenced MALT1 translocations. DNA of C. psittaci was detected in 11% of the 46 lymphomas: two orbital EMZL and three non-OAL. All 20 benign ocular lesions were negative for C. psittaci. The low prevalence of C. psittaci in OAL suggests geographical differences in the etiology of this entity. International studies are needed to clarify the role of C. psittaci in OALs.

Lack of an association betweenChlamydia psittaciand ocular adnexal lymphoma

The objective of this study was to assess whether there is PCR evidence for C. psittaci DNA in ocular adnexal lymphoma specimens collected in an academic institution in the U.S. This was a retrospective, single-center study of patients from 1994 - 2004. We used 28 ocular adnexal lymphoma biopsy specimens from adult patients, 16 control lymphoma specimens from patients with systemic lymphomas not involving the ocular adnexa, and five control benign adnexal tissue samples. The presence of C. psittaci DNA was investigated by polymerase chain reaction (PCR) in each group. Two different assays were utilized: (1) conventional PCR/gel based assay targeting a 111-bp fragment of the 16S gene and (2) a real-time PCR assay amplifying a 148-bp portion of the 16S gene with detection via a specific fluorescent probe. Amplification was carried out to 60 cycles. Positive controls consisted of isolated DNA from C. psittaci strains VS1, CP3, and FP. A human DNA internal control was used to assess sample DNA quality and amplification success. Mean outcome measure was the presence of C. psittaci DNA. Using both assays, all patient samples in all categories yielded negative results. Both assays detected C. psittaci DNA from isolated strains. Internationally, Chlamydia psittaci has been associated with ocular adnexal lymphomas with great variability. Similar to several other recent studies in the USA, our study could not confirm the presence of C. psittaci in ocular adnexal lymphomas. Differences in the prevalence of C. psittaci infection in various geographic regions or technical differences in the application of the assays may underlie the variability in the association between C. psittaci and ocular adnexal lymphoma.

[The spectrum of microbiological agents causing pulmonary MALT-type lymphomas. A 16S rRNA-based analysis of microbial diversity]

For several anatomical localisations of extranodal marginal zone B-cell lymphoma of MALT type (eMZBCL), an association with chronic inflammation caused by microbiological agents (e.g. Helicobacter pylori in the stomach) has been described. In the lung, a link between lymphomagenesis and a defined causative organism is still missing. A comprehensive diversity survey using 16S-rDNA library construction followed by restriction fragment length polymorphism (RFLP) analysis, sequencing, and phylogenetic tree construction was employed for nine cases each of BALT lymphoma and control lung tissues (normal foetal lung, pneumonitis, carcinoid). This highly sensitive method, hereafter termed SHARP screening allowed for identification of the entire bacterial population in the tissue in a cultivation-independent manner. It was noteworthy that in eight of the nine cases of BALT lymphoma, bacteria of the Alcaligenaceae family (Alcaligenes, Achromobacter, AKIW733), were detected, whereas none of the control cases showed the presence of these clades. 16S-rDNA library construction in combination with RFLP screening and phylogenetic analyses, hereafter described as SHARP screening, is a cultivation-independent tool for analysing the microbial environment in chronic inflammation processes giving rise to extranodal marginal zone B-cell lymphomas of MALT-type. Betaproteobacteria of the Alcaligenaceae family may be affiliated with and possibly involved in the lymphomagenesis of BALT lymphomas.

Extranodal marginal zone lymphoma of the ocular adnexa

Lymphomas of the ocular adnexa are a heterogeneous group of malignancies, composing approximately 1% to 2% of non-Hodgkin lymphomas (NHLs) and 8% of extranodal lymphomas. The most common subtype, accounting for up to 80% of cases of primary ocular adnexal lymphoma, is marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) type. In the recent past, there have been significant advances in our understanding of the clinical characteristics, morphology and phenotype, etiology, pathogenesis, diagnosis, natural history, treatment approaches, outcome, and prognostic factors of this disease entity. Novel immunologic and molecular techniques have aided in the distinction between MALT lymphoma and other lymphoproliferative disorders and led to the identification of tissue markers of prognostic significance. Modern imaging modalities provide invaluable tools for accurate staging and treatment planning. Besides radiotherapy and chemotherapy, a variety of new treatment options have emerged in the management of patients with ocular adnexal MALT lymphoma, especially monoclonal antibody therapy and antibiotic therapy against Chlamydia psittaci, which has been associated with the pathogenesis of ocular adnexal lymphomas in some parts of the world. In this review, we present a state-of-the-art summary of ocular adnexal MALT lymphomas.

Infectious agents and lymphoma development: molecular and clinical aspects

This review is focused on the role of infectious agents in the development of some lymphoma entities. Associations involving bacterial infections mostly regard marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT)-type. Some paradigmatic examples of these associations include the Helicobacter pylori-related gastric MALT lymphoma and the more recently reported links between Chlamydophila psittaci and ocular adnexal MALT lymphomas and Borrelia burgdorferi and cutaneous MALT lymphomas. The well-documented association between Epstein-Barr virus infection and related lymphoproliferative disorders are analysed as an example of lymphotropic virus with tumourigenic activity. Molecular, biological and clinical features as well as therapeutic implications of these associations are analysed and future perspectives in this field are discussed.

A20 deletion is associated with copy number gain at the TNFA/B/C locus and occurs preferentially in translocation-negative MALT lymphoma of the ocular adnexa and salivary glands

The genetic basis of MALT lymphoma is largely unknown. Characteristic chromosomal translocations are frequently associated with gastric and pulmonary cases, but are rare at other sites. We compared the genetic profiles of 33 ocular adnexal and 25 pulmonary MALT lymphomas by 1 Mb array-comparative genomic hybridization (CGH) and revealed recurrent 6q23 losses and 6p21.2-6p22.1 gains exclusive to ocular cases. High-resolution chromosome 6 tile-path array-CGH identified NF-kappaB inhibitor A20 as the target of 6q23.3 deletion and TNFA/B/C locus as a putative target of 6p21.2-22.1 gain. Interphase fluorescence in situ hybridization showed that A20 deletion occurred in MALT lymphoma of the ocular adnexa (8/42=19%), salivary gland (2/24=8%), thyroid (1/9=11%) and liver (1/2), but not in the lung (26), stomach (45) and skin (13). Homozygous deletion was observed in three cases. A20 deletion and TNFA/B/C gain were significantly associated (p<0.001) and exclusively found in cases without characteristic translocation. In ocular cases, A20 deletion was associated with concurrent involvement of different adnexal tissues or extraocular sites at diagnosis (p=0.007), a higher proportion of relapse (67% versus 37%) and a shorter relapse-free survival (p=0.033). A20 deletion and gain at TNFA/B/C locus may thus play an important role in the development of translocation-negative MALT lymphoma.

Ocular surface tumors

Tumors of the conjunctiva and cornea comprise a large and varied spectrum of conditions. These tumors are grouped into two major categories of congenital and acquired lesions. The acquired lesions are further subdivided based on origin of the mass into surface epithelial, mucoepidermoid, melanocytic, vascular, fibrous, neural, histiocytic, myxoid, myogenic, lipomatous, lymphoid, leukemic, metastatic and secondary tumors. Ocular surface tumors include a variety of neoplasms originating from squamous epithelium, melanocytic tumors and lymphocytic resident cells of the conjunctival stroma. In this review, we highlight clinical features of these lesions, important diagnostic and investigative tools and standard care of management.

Inflammatory cells and immune microenvironment in malignant lymphoma

It has become clear that the biological and clinical behaviour of malignant lymphoma is not only determined by the properties of the tumour cells themselves but are also largely by the interaction of the tumour cells with their nonmalignant microenvironment. The composition and functional status of the tumour microenvironment is highly variable between different classes of malignant lymphoma and may provide both growth-supportive and growth suppressive signals via components of the adaptive and innate immune response. In this review, the functional interactions and clinical consequences of these insights are discussed in indolent and aggressive B-cell lymphomas and in classical Hodgkin's lymphoma.

Assessment of the role of hepatitis C, Helicobacter pylori and autoimmunity in MALT lymphoma of the ocular adnexa in 45 Austrian patients

INTRODUCTION

A recent series from Italy has suggested a pathogenic link between hepatitis C virus and MALT lymphoma of the ocular adnexa. The hypothesis of our study was to prove this concept in Austrian patients with MALT lymphoma of the ocular adnexa.

MATERIALS AND METHODS

A total of 45 patients presenting with MALT lymphoma of the ocular adnexa were assessed for the presence of infection with hepatitis A, B and C. Furthermore, extensive staging to evaluate the extent of disease along with analysis of Helicobacter pylori-infection, the presence or absence of autoimmune diseases (AD) and assessment of MALT-lymphoma specific genetic changes was performed.

RESULTS

Only 2/45 (4%) patients were tested positive for hepatitis C, while 10/45 (22%) had an underlying AD and 15/39 (38%) had HP infection. Chromosomal aberrations were detected in 19 (54%) of 35 patients analyzed. Disseminated disease was a significant risk factor for relapse (p=0.014).

DISCUSSION

Our series suggests that infection with hepatitis C is not a significant contributor to the pathogenesis of ocular adnexal MALT lymphoma in the Austrian population, while a substantial proportion of these patients suffer from autoimmune conditions.

Chlamydophila psittaci infections in birds: a review with emphasis on zoonotic consequences

The first part of the present review gives an overview on the history of infectious agents of the order Chlamydiales and the general infection biology of Chlamydophila (C.) psittaci, the causative agent of psittacosis. In the second part, the classification of C. psittaci strains, as well as issues of epidemiology of avian chlamydiosis., disease transmission routes, clinical disease, public health significance, present legislation and recommendations for prevention and control are reviewed.

The role of infectious agents in the etiology of ocular adnexal neoplasia

Given the fact that infectious agents contribute to around 18% of human cancers worldwide, it would seem prudent to explore their role in neoplasms of the ocular adnexa: primary malignancies of the conjunctiva, lacrimal glands, eyelids, and orbit. By elucidating the mechanisms by which infectious agents contribute to oncogenesis, the management, treatment, and prevention of these neoplasms may one day parallel what is already in place for cancers such as cervical cancer, hepatocellular carcinoma, gastric mucosa-associated lymphoid tissue lymphoma and gastric adenocarcinoma. Antibiotic treatment and vaccines against infectious agents may herald a future with a curtailed role for traditional therapies of surgery, radiation, and chemotherapy. Unlike other malignancies for which large epidemiological studies are available, analyzing ocular adnexal neoplasms is challenging as they are relatively rare. Additionally, putative infectious agents seemingly display an immense geographic variation that has led to much debate regarding the relative importance of one organism versus another. This review discusses the pathogenetic role of several microorganisms in different ocular adnexal malignancies, including human papilloma virus in conjunctival papilloma and squamous cell carcinoma, human immunodeficiency virus in conjunctival squamous carcinoma, Kaposi sarcoma-associated herpes virus or human herpes simplex virus-8 (KSHV/HHV-8) in conjunctival Kaposi sarcoma, Helicobacter pylori (H. pylori,), Chlamydia, and hepatitis C virus in ocular adnexal mucosa-associated lymphoid tissue lymphomas. Unlike cervical cancer where a single infectious agent, human papilloma virus, is found in greater than 99% of lesions, multiple organisms may play a role in the etiology of certain ocular adnexal neoplasms by acting through similar mechanisms of oncogenesis, including chronic antigenic stimulation and the action of infectious oncogenes. However, similar to other human malignancies, ultimately the role of infectious agents in ocular adnexal neoplasms is most likely as a cofactor to genetic and environmental risk factors.

Extranodal lymphoma

Lymphomas arising in extranodal sites are intriguing. The types of lymphomas encountered vary widely from one extranodal site to another. For many types of extranodal lymphomas, there are distinctive clinicopathologic features, sometimes including association with an underlying immunodeficiency syndrome, autoimmune disease, infection, or other immunologic disorder, or a predilection to affect patients of certain ethnic origins. Presented below is a review of lymphomas that are encountered most often in extranodal sites.

Clinicopathological features of primary cutaneous B-cell lymphomas from an academic regional hospital in central Italy: no evidence of Borrelia burgdorferi association

We reviewed the clinico-pathological features of 73 primary cutaneous B-cell lymphomas (PCBCLs), diagnosed in 10 years in Marche region in central Italy, which included 16 marginal zone lymphomas (MZL), 33 follicle centre lymphomas (FCL) and 24 diffuse large B cell lymphomas (DLBCL). We also investigated the presence of Borrelia burgdorferi in tissues by polymerase chain reaction. Differences in age, sex, location site, response to therapy, disease recurrence and 5-year disease-specific survival were observed among the 3 histological groups. Specific DNA sequences of Borrelia burgdorferi were not detected in any of the 73 cases of PCBCL. We conclude that PCBCLs in Marche region behave according to the literature data and do not seem to be associated with Borrelia burgdorferi. Additional investigations should be performed on other possible etiologies, at least in our geographical area.