Low prevalence ofChlamydia psittaciin ocular adnexal lymphomas from Cuban patients

The Biology of Ocular Adnexal Marginal Zone Lymphomas

This review focuses on the biology of ocular adnexal marginal zone B-cell lymphomas of the mucosa-associated lymphatic tissue (MALT) (OAMZL) subtype. The ocular adnexa includes all structures and tissues within the orbit except for the eye bulb. In the region of the ocular adnexa, MALT lymphomas represent the most common subtype of lymphoma, accounting for around 8% of all non-Hodgkin lymphomas. These lymphomas are often preceded by inflammatory precursor lesions. Either autoantigens or infectious antigens may lead to disease development by functioning as continuous antigenic triggers. This triggering leads to a constitutive activation of the NF-κB signaling pathway. The role of antigenic stimulation in the pathogenesis of OAMZL is supported by the detection of somatic mutations (partially with further intraclonal diversity) in their rearranged immunoglobulin V genes; hence, their derivation from germinal-center-experienced B cells, by a restricted IGHV gene usage, and the validation of autoreactivity of the antibodies in selected cases. In the established lymphomas, NF-κB activity is further enforced by mutations in various genes regulating NF-κB activity (e.g., TNFAIP3, MYD88), as well as recurrent chromosomal translocations affecting NF-κB pathway components in a subset of cases. Further pathogenetic mechanisms include mutations in genes of the NOTCH pathway, and of epigenetic regulators. While gene expression and sequencing studies are available, the role of differential methylation of lymphoma cells, the role of micro-RNAs, and the contribution of the microenvironment remain largely unexplored.

Ocular adnexal lymphoma: an updated review of pathogenesis, diagnosis, and treatment

Lymphoma is the most common primary tumor of the orbit, accounting for 55% of all orbital malignancies. When divided into histopathological subtypes, extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) comprises the largest proportion. Clinical manifestations are unspecific, but in patients with slow-growing painless orbital mass, or red conjunctival lesion suggestive of ‘salmon patch’, ocular adnexa lymphoma (OAL) should be suspected. Although the pathogenetic mechanism of ocular adnexal MALT lymphoma (OAML) is not yet fully understood, the relationship between OAML and Chlamydia psittaci has been hypothesized recently, similar to that between gastric MALT lymphoma and Helicobacter pylori. This suggests a new treatment option for OAML; bacterial eradication therapy with systemic antibiotics. Several other treatment methods for OAML have been introduced, but no treatment guidelines have been established yet. In this article, we summarize the current knowledge on the clinical features, pathogenesis, diagnostic methods, therapeutic strategies, and prognosis of OAML.

Prevalence of Chlamydia psittaci, Chlamydia pneumoniae, and Chlamydia trachomatis Determined by Molecular Testing in Ocular Adnexa Lymphoma Specimens

OBJECTIVES

To assess the prevalence of Chlamydia psittaci, Chlamydia pneumoniae, and Chlamydia trachomatis in ocular adnexa lymphoma (OAL) determined by molecular testing in different countries and the potential association of Chlamydia infection with mucosa-associated lymphoid tissue (MALT) histotype by performing a systematic review and meta-analysis.

METHODS

Electronic databases were searched for studies assessing the presence of Chlamydia in OAL. Pooled prevalence of the three Chlamydia species was calculated in each country. An odds ratio was calculated for the association between Chlamydia and MALT histotype, with a significant P < .05.

RESULTS

Thirty-seven studies with 1,188 OALs were included. Pooled prevalence of C psittaci, C pneumoniae, and C trachomatis by country was done. Chlamydia infection was significantly associated with MALT histotype (odds ratio, 2.183; P = .027).

CONCLUSIONS

The involvement of C psittaci in OAL is highly variable, with the highest prevalence in Italy and Korea. Chlamydia is associated with MALT histotype.

Bilateral benign reactive lymphoid hyperplasia of the conjunctiva: a case treated with oral doxycycline and review of the literature

Background

To report a case of bilateral benign reactive lymphoid hyperplasia (BRLH) of the conjunctiva treated with oral doxycycline and perform review of the literature evaluating the presentation, treatment and risk of transformation to lymphoma.

Case presentation

A case report is described and review of the literature from January 1975 to January 2019 was performed. A 30-year-old man presented with bilateral enlarging fleshy pink medial canthal conjunctival lesions. Incisional biopsy revealed BRLH. Oral doxycycline was initiated (100 mg two times a day) for a total of 2 months. Both lesions decreased in size significantly at the patient’s two-month follow up visit. The residual lesion in the right eye was excised along with an adjacent pterygium and the patient has been free of recurrence for the past 1.5 years. The lesion in the left eye has remained stable in size after cessation of the oral doxycycline. A total of 235 cases of conjunctival BRLH were identified in our literature search. The mean age at diagnosis was 35.2 years (range, 5 to 91 years). BRLH lesions were unilateral in 75% of patients and bilateral in 25% of them. Seven patients (2.9%) had a concurrent Epstein-Barr virus (EBV) infection at the time of lesion appearance. The most common treatments were surgical excision (155/235 or 65.9%) and corticosteroids (30/235 or 12.7%), while 14% (33/235) of the patients were observed and 4.6% (11/235) received external beam radiotherapy alone. Recurrence occurred in ten patients (10/235 or 4.2%), of whom five had undergone surgical excision alone, two excision followed by external beam radiotherapy, one excision and oral corticosteroids, one radiotherapy alone and one had been treated with topical corticosteroids. Overall, only 2 of the 235 reported cases (0.8%) developed malignancy, one localized to the conjunctiva and one systemic.

Conclusions

Benign reactive lymphoid hyperplasia is one of the lymphoproliferative disorders of the conjunctiva and ocular adnexa. Extensive literature review shows that most cases are treated with surgery, steroids or observation. Oral doxycycline may be considered an alternative non-invasive treatment of BRLH conjunctival lesions. BRLH lesions warrant careful follow up as they can rarely transform into conjunctival or systemic lymphoma.

Recent advances in understanding the biology of marginal zone lymphoma

There are three different marginal zone lymphomas (MZLs): the extranodal MZL of mucosa-associated lymphoid tissue (MALT) type (MALT lymphoma), the splenic MZL, and the nodal MZL. The three MZLs share common lesions and deregulated pathways but also present specific alterations that can be used for their differential diagnosis. Although trisomies of chromosomes 3 and 18, deletions at 6q23, deregulation of nuclear factor kappa B, and chromatin remodeling genes are frequent events in all of them, the three MZLs differ in the presence of recurrent translocations, mutations affecting the NOTCH pathway, and the transcription factor Kruppel like factor 2 ( KLF2) or the receptor-type protein tyrosine phosphatase delta ( PTPRD). Since a better understanding of the molecular events underlying each subtype may have practical relevance, this review summarizes the most recent and main advances in our understanding of the genetics and biology of MZLs.

Chlamydia and ocular adnexal lymphomas: An Indian experience

CHLAMYDIA AND OCULAR ADNEXAL LYMPHOMAS

AN INDIAN EXPERIENCE: Ocular adnexal lymphomas (OALs) are a heterogeneous group of malignancies, majority being extranodal mucosa-associated lymphoid tissue (MALT) type. Different geographical regions have reported association of Chlamydia with OALs (MALT type). In India, role of Chlamydia in OALs remains unexplored. The aim of this study was to detect Chlamydia and to correlate with clinicopathological features of OALs in India. The clinicopathological features of 41 OAL cases were studied prospectively. Chlamydia DNA was detected by genus specific PCR amplifying major outer membrane protein (MOMP) gene followed by DNA sequencing. Chlamydia immunoexpression was evaluated by immunofluorescence and immunohistochemistry. The results were correlated with clinicopathological features including follow-up and survival. Chlamydia genome was detected in 3/41 (7.3%) OAL cases by PCR. Direct sequencing revealed C. trachomatis in 3 positive cases. Immunofluorescence and immunohistochemistry showed Chlamydia antigen in 5/41 and 1/41 cases respectively. Immunofluorescence demonstrated higher sensitivity than immunohistochemistry. A significant association was observed between Chlamydia positivity and orbital location (P=0.05). Follow-up revealed relapse in 2 Chlamydia positive cases (P=0.056). Our results demonstrate for the first time presence of C. trachomatis genome in 7.3% OAL cases in India. As no other reports are documented, more detailed studies from different regions within India are needed to explore status of Chlamydia in OALs.

An update on ocular adnexal lymphoma

Ocular adnexal lymphoma (OAL) is a relatively common lesion in the practice of ophthalmic oncology. Although OALs are usually primary tumors, secondary involvement of the ocular adnexae by systemic lymphoma is also possible. The clinical and radiological features of OAL are non-specific. Thorough morphological evaluation, aided by immunostaining, cytogenetic studies and molecular testing, are necessary for accurate diagnosis.

Descriptive epidemiology of ophthalmic and ocular adnexal non-Hodgkin's lymphoma

In this article, we provide an update on incidence rates of ophthalmic non-Hodgkin's lymphoma (NHL), in the context of other NHL, in the USA. We also provide population-based estimates of incidence and survival for ocular adnexal NHL, the most common form of ophthalmic NHL, for which descriptive patterns have not been previously reported. Ophthalmic and ocular adnexal NHL have unique incidence patterns, including equal rates among both genders, predominance among Asians/Pacific Islanders, and steady and rapid increases in the past few decades. Studies of international variations in the incidence of ocular adnexal NHL may provide clues as to the underlying mechanisms influencing its unique epidemiology.

Ocular adnexal non-Hodgkin's lymphoma: a review of epidemiology and risk factors

Ocular adnexal non-Hodgkin's lymphoma (NHL), the most common form of ophthalmic NHL, has a unique incidence pattern showing a steady and rapid increase in the past few decades, nearly equal rates among both genders, and predominance among Asians/Pacific Islanders. No major cause for ocular adnexal NHL has been identified, although infectious agents, immune disorders and genetic/epigenetic factors have all been implicated in its etiology. Identifying putative risk factors and biologic mechanisms leading to carcinogenesis in ocular adnexal NHL may enable implementation of effective preventive and/or therapeutic approaches for this malignancy. This article summarizes current knowledge on epidemiology of ocular adnexal NHL and the role of various potential risk factors in its etiology.

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.

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.

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.

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.

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.

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.

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.

Ocular adnexal MALT lymphoma: an intriguing model for antigen-driven lymphomagenesis and microbial-targeted therapy

Non-Hodgkin's lymphomas constitute one half of malignancies arising in the orbit and the ocular adnexae. Mucosa-associated lymphoid tissue (MALT)-type lymphoma is the most common histological category in this anatomic region. The incidence of ocular adnexal lymphoma of mucosa-associated lymphoid tissue-type (OAML) is increasing and recent studies offered new relevant insights in molecular, pathogenetic and therapeutic issues on these neoplasms. A pathogenetic model of antigen-driven lymphoproliferation similar to that reported for Helicobacter pylori-related gastric MALT lymphomas has been hypothesized for OAML. This notion is supported by the association between OAML and Chlamydophila psittaci infection, an association that is of likely pathogenetic relevance and may influence both the biological behavior and the therapeutic management of these neoplasms. However, this association displays evident geographical variability indicating that other etiopathogenic agents could be involved. These recent acquisitions coupled with the occurrence of chromosomal translocations and other genetic alterations, as well as additional risk factors like autoimmune disorders have contributed to render OAML an exciting challenge for a broad group of physicians and scientists. OAML is an indolent and rarely lethal malignancy that, in selected patients, can be managed with observation alone. Lymphomatous lesions are frequently responsible for symptoms affecting patient's quality of life, requiring, therefore, immediate treatment. Several therapeutic strategies are available, often associated with relevant side-effects. However, the therapeutic choice in OAML is not supported by consolidated evidence due to the lack of prospective trials. In this review, we analyze the most relevant biological, molecular, pathological and clinical features of OAML and propose some therapeutic guidelines for patients affected by this malignancy.

Meta-analyses of the association between Chlamydia psittaci and ocular adnexal lymphoma and the response of ocular adnexal lymphoma to antibiotics

BACKGROUND

There are conflicting reports regarding the association between Chlamydia psittaci (Cps) and ocular adnexal lymphoma (OAL) and the efficacy of antibiotics for OAL. In the current study, the authors attempted to clarify the association between Cps and OAL and the efficacy of antibiotics for OAL.

METHODS

Two meta-analyses were conducted. One focused on the association between Cps and OAL across geographic regions and among different studies. The other was a meta-analysis of the response of OAL to antibiotic treatment.

RESULTS

The authors identified 11 studies of Cps prevalence that included 458 cases of OAL from 10 different countries. Four studies regarding the efficacy of oral antibiotics to treat OAL were found. One hundred four of the 458 OAL specimens (23%) and 87 of the 346 mucosa-associated lymphoid tissue (MALT) lymphoma specimens (25%) were found to be positive for Cps. Ninety-four of the 104 Cps-positive OAL specimens (90%) came from 3 of the 11 studies. There was wide variation noted between geographic regions and even between studies from the same geographic region with regard to the rate of Cps positivity. The 4 studies concerning the efficacy of antibiotics for OAL were from Italy, Austria, Taiwan, and the U.S. and included 42 patients. Twenty patients (48%) achieved some response (complete response in 8 patients, partial response in 8 patients, and minimal response in 4 patients). Twenty patients also had stable disease, and 2 patients progressed during antibiotic therapy. Objective documentation of response (radiographs or clinical slit-lamp photographs) was available for only 3 of the 42 patients. Seven additional patients developed disease recurrence after their initial response or stable disease after antibiotic therapy; 6 of these cases of disease recurrence occurred during the first 12 months of follow-up.

CONCLUSIONS

The findings of the current study suggest a striking variability in the association between Cps and OAL across geographic regions and even between studies from the same geographic regions. The overall rate of Cps positivity in our meta-analysis (23%) was much lower than that reported in the original report. The current study findings also suggest that antibiotics have variable efficacy against OAL. Future prospective trials with standard objective response criteria and a longer follow-up period would be necessary to evaluate the role of antibiotics in the treatment of OAL further.