Extranodal Marginal Zone B-cell Lymphomas of the Ocular Adnexa

Enhancing prognostication and personalizing treatment of extranodal marginal zone lymphoma

INTRODUCTION

Extranodal marginal zone lymphoma (EMZL) of mucosa-associated lymphoid tissue is an indolent lymphoma originating from marginal zone B-cells and associated with chronic inflammation. EMZL demonstrates distinct genomic alterations according to the primary extranodal site of disease but commonly affects signaling pathways including NF-ĸB, B-cell receptor, and NOTCH. Treatment with radiation therapy is commonly implemented in localized diseases, and multiple agents are available for patients with advanced-stage diseases in need of therapy. Bendamustine with rituximab is a frontline platform associated with high efficacy.

AREAS COVERED

Clinical features, diagnosis, genomics, models enabling risk stratification, treatment options, and future directions.

EXPERT OPINION

The lack of consistent genotyping profile in EMZL precludes the development of tissue and circulatory biomarkers for the diagnosis, risk stratification, and monitoring of minimal residual disease. Furthermore, the biological heterogeneity observed in extranodal sites associated with overall limited genomic data prevents the testing of druggable pathways aiming for a personalized treatment approach. Future clinical trials should focus on EMZL considering the unique clinical characteristics in the eligibility criteria and response assessment to better inform efficacy of novel agents and delineate sequences of therapies.

[Lymphoma of the eye and its adnexa : Modern pathological diagnostics and systemic treatment]

BACKGROUND

Malignant lymphomas of the eye and its adnexal structures account for approximately 5-15% of extranodal lymphomas. According to anatomic and biological criteria, two large groups of lymphomas in and around the eye need to be distinguished: (1) primary lymphomas of intraocular structures and (2) primary lymphomas of ocular adnexa. Furthermore, there is a large spectrum of secondary manifestations of malignant lymphomas in ocular and periocular structures.

OBJECTIVE

This article gives a summary of the classification and molecular pathology of various intraocular and periocular lymphomas as well as oncological systemic treatment with a focus on primary vitreoretinal lymphomas.

METHODS

A selective literature search was carried out in PubMed on the topic of intraocular and periocular lymphomas and own experiences are presented.

RESULTS

The treatment of primary vitreoretinal lymphomas (PVRL) is an interdisciplinary challenge and despite the apparently localized disease, systemic treatment concepts are necessary to reduce the high risk of secondary involvement of the central nervous system (CNS). Therefore, it is crucial that the substances used can penetrate the CNS, and protocols should be chosen in accordance with the treatment concepts for primary CNS lymphomas. The knowledge on the genetics and biology of ocular lymphomas generated by modern high throughput methods enable not only improved diagnostics using molecular methods but also provide rationales for targeted therapeutic approaches.

CONCLUSION

A deep understanding of the biological and molecular principles of intraocular and periocular lymphomas forms a basic prerequisite for precise diagnostics and the use of targeted systemic treatment.

Uveal lymphoid hyperplasia: treatment with combination antibiotics and steroids

BACKGROUND/AIMS

Uveal lymphoid hyperplasia (formerly benign reactive hyperplasia of the choroid) spans histopatholological characteristics ranging from reactive hyperplasia to low-grade lymphoid neoplasm. There is strong evidence that other low-grade lymphoid neoplasms, particularly of gastric derivations, respond to oral antibiotics. Here, we explore that response of uveal lymphoid hyperplasia to treatment with only oral antibiotics and steroids.

METHODS

Four eyes of three patients with clinically diagnosed uveal lymphoid hyperplasia were treated with a course of oral antibiotics and steroids. The main outcome was clinical response of choroidal infiltrate by optical coherence tomography (OCT) measurements of choroidal thickness and visual acuity. Secondary outcome measure included local and systemic recurrence. Clinical response was evaluated by clinical exam, fundus photography, ultrasound and OCT.

RESULTS

All 4 eyes displayed a clinical response at a median 2 weeks after starting oral antibiotics and steroid course. The choroidal infiltration regressed as evidenced by: decrease of choroidal thickness by a median of 421 nm, myopic shift in refractive error by a median of 0.50 Diopters, and improved vision by a median of 1.5 Snellen lines. At a median of 51-month follow-up, all four eyes had a sustained complete response and no patient has developed systemic disease to date.

CONCLUSIONS

In this small cohort of patients with uveal lymphoid hyperplasia, measurable and sustained clinical responses were observed with antibiotics/steroids, without systemic recurrence. This suggests combination antibiotic/steroid therapy is a reasonable treatment for select cases of uveal lymphoid hyperplasia, and may avoid the need for systemic chemotherapy/monoclonal antibody and/or external beam irradiation.

Ocular adnexal mucosa-associated lymphoid tissue lymphoma: a narrative review

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.

MALT lymphoma of the tongue: An unusual site that may present a diagnostic challenge

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is a low-grade B cell lymphoma that can affect any organ, usually preceded by acquisition of MALT in response to antigenic stimulus provided by infections or autoimmune diseases. Most often, MALT lymphoma involves the stomach (about 35% of cases), followed by the ocular adnexal region, skin, lungs, and salivary glands, but virtually any extranodal site can be involved. MALT lymphomas are less common at sites of normal MALT tissue, such as Waldeyer ring and the ileocecal region of the gastrointestinal tract. Lymphomas involving the tongue are extremely rare and represent approximately 3% of all lymphomas involving the head and neck region. In this study, we discuss potentially challenging diagnostic aspects of MALT lymphoma involving the tongue and review and summarize the available literature about this topic.

Kappa and lambda immunohistochemistry and in situ hybridization in the evaluation of atypical cutaneous lymphoid infiltrates

BACKGROUND

Atypical cutaneous lymphoid infiltrates are challenging lesions in dermatopathology. We present a summary of the literature regarding kappa and lambda immunohistochemistry (IHC) and in situ hybridization (ISH) in the evaluation of atypical cutaneous or mucosal lymphoid infiltrates.

METHODS

Relevant articles from 1967 to 2018 in the English language were identified and summarized. In the absence of larger studies, case series of n ≥ 3 were included.

RESULTS

Sixty-three articles assessing kappa and lambda IHC and/or ISH were identified. Most focused on marginal zone lymphomas. Other lymphomas included follicle center lymphoma, diffuse large B-cell lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma, mantle cell lymphoma, lymphoplasmacytic lymphoma, plasmablastic lymphoma, multiple myeloma, monoclonal gammopathy of undetermined significance, and polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes (POEMS). Non-neoplastic lesions included reactive lymphoid hyperplasia, cutaneous plasmacytosis, connective tissue disease, IgG4-related disease, acrodermatitis chronic atrophicans, Zoon balanitis, dermatitides, and infiltrates around epithelial dysplasias/neoplasias.

CONCLUSION

Kappa and lambda IHC and ISH are useful tools in the evaluation of cutaneous B-cell lymphomas and plasma cell neoplasms. The literature supports that the detection of light-chain restriction by IHC and ISH is one of the most useful findings in the differential diagnosis of reactive lymphoid hyperplasia vs B-cell lymphoma with plasmacytic differentiation.

TBL1XR1 Mutations in Primary Marginal Zone Lymphomas of Ocular Adnexa are Associated with Unique Morphometric Phenotypes

PURPOSE

Extranodal marginal zone B-cell lymphoma (EMZL) of mucosa-associated lymphoid tissue (MALT) that affects the ocular adnexa, also known as ocular adnexal MALT lymphomas (OAML), are low-grade lymphomas that mostly affect elderly individuals. This study was conducted to explore the genetic and microbial drivers of OMAL, and unique morphometric phenotypes associated with these mutations and infections.

MATERIALS AND METHODS

In this study, we performed targeted deep sequencing of 8 OAML cases to identify its potential genetic and microbial drivers. We additionally performed computational digital image analysis of cases to determine if morphologic features corresponded to genetic mutations and disease biology.

RESULTS

We identified TBL1XR1 as recurrently mutated in OAML (4/8), and mutations in several other oncogenes, tumor suppressors, transcription regulators, and chromatin remodeling genes. Morphologically, OAML cases with mutations in TBL1XR1 showed lymphoma cells with significantly lower circularity and solidity by computational digital image analysis (p-value <0.0001). Additionally, cases of OAML with mutations in TBL1XR1 showed equivalent or increased vascular density compared to cases without mutations in TBL1XR1. Finally, we did not find any infectious microbial organisms associated with OAML.

CONCLUSIONS

Our study showed recurrent mutations in TBL1XR1 are associated with unique morphometric phenotypes in OMAL cases. Additionally, mutations in genes associated with the methylation status of histone 3, nuclear factor (NF)-κB pathway, and NOTCH pathway were enriched in OMAL cases. Our findings have biologic and clinical implications as mutations in TBL1XR1 and other genes have the potential to be used as markers for the diagnosis of OAML, and also demonstrate a specific biologic phenotypic manifestation of TBL1XR1 mutations.

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.

Marginal zone B-cell lymphoma: lessons from Western and Eastern diagnostic approaches

Marginal zone B-cell lymphomas (MZLs) are a group of clinically indolent B-cell lymphomas postulated to derive from memory B lymphocytes in the 'marginal zone' of secondary lymphoid tissue. Today, MZL is recognised as a nosological umbrella term encompassing distinct entities with some shared phenotypic and genotypic features, including extranodal marginal zone B-cell lymphoma (EMZL) or mucosa-associated lymphoid tissue (MALT) lymphoma, splenic MZL, and nodal MZL, accounting for approximately 70%, 20%, and 10% of MZLs, respectively. These lymphomas share some phenotypic and genotypic features and have some variants and related provisional diseases, but are different in regards to their clinical and molecular characteristics. In addition, they are frequently associated with chronic antigenic stimulation represented either by infectious agents, particularly bacteria and viruses, or autoimmune diseases as exemplified by Sjögren syndrome, Hashimoto thyroiditis, and newly recognised IgG4-related disease. Furthermore, several chromosomal translocations have been identified in EMZL. In this review, we will focus on the updated histopathological criteria and the main problems with differential diagnoses in order to aid the diagnostic approach in our routine practice.

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.

International multicentre retrospective cohort study of ocular adnexal marginal zone B-cell lymphoma

Backgrounds/aims

To date, this is the largest cohort study on extranodal marginal zone B-cell lymphoma (EMZL) of the ocular adnexa (OA). The aim of the study was to characterise the clinical features of OA-EMZL.

Methods

A retrospective multicentre study involving seven international eye cancer centres. Data were collected from 1 January 1980 through 31 December 2017. A total of 689 patients with OA-EMZL were included.

Results

The median follow-up time was 42 months. The median age was 62 years (range, 8–100 years), and 55 % (378/689 patients) of patients were women. The majority of patients (82%, 558/680 patients) were diagnosed with primary OA-EMZL with Ann Arbor stage IE (90%, 485/541 patients) and American Joint Committee on Cancer stage T2 (61%, 340/557 patients) at the time of diagnosis. The orbit (66%, 452/689 patients) and the conjunctiva (37%, 255/689 patients) were the most frequently involved anatomical structures. The 5-year, 10-year and 20-year disease-specific survival (DSS) were 96%, 91% and 90%, respectively. Stage IE patients treated with external beam radiation therapy (EBRT) as monotherapy (10-year DSS, 95%) were found to have a better DSS than stage IE patients treated with chemotherapy (10-year DSS, 86%). Stage IIIE/IVE patients treated with chemotherapy and rituximab had a better DSS (10-year DSS, 96%) than stage IIIE/IVE patients treated with chemotherapy without rituximab (10-year DSS, 63%).

Conclusions and relevance

EMZL is a slow-growing tumour with an excellent long-term survival. Low-dose EBRT as monotherapy should be considered in localised OA-EMZL. Rituximab-based chemotherapy should be chosen in those patients with disseminated disease.

Orbital lymphoma

Orbital lymphomas constitute 50-60% of ocular adnexal lymphomas. A total of 2211 cases of orbital lymphoma with a known subtype have been reported in the last 24 years (1994-2017). The vast majority of orbital lymphomas are of B-cell origin (97%), of which extranodal marginal zone B-cell lymphoma (EMZL) (59%) is the most common subtype, followed by diffuse large B-cell lymphoma (23%), follicular lymphoma (9%), and mantle cell lymphoma (5%). Orbital lymphoma is primarily a disease of the elderly. Gender distribution varies according to lymphoma subtype. However, extranodal marginal zone B-cell lymphoma (53%) and follicular lymphoma (75%) show a female predominance, whereas diffuse large B-cell lymphoma shows an even gender distribution. Mantle cell lymphoma has a striking male predominance of 80%. The histopathological subtype and the clinical stage of the disease are the best indicators of prognosis and patient outcome. Low-grade lymphomas such as extranodal marginal zone B-cell lymphoma and FL have a good prognosis, whereas high-grade lymphomas (diffuse large B-cell lymphoma and mantle cell lymphoma) are associated with a poor prognosis. When managing solitary low-grade lymphomas, radiotherapy is the treatment of choice. Chemotherapy, with or without radiotherapy, should be chosen for disseminated and high-grade lymphomas.

High Frequency of MYD88 L265P Mutation in Primary Ocular Adnexal Marginal Zone Lymphoma and Its Clinicopathologic Correlation: A Study From a Single Institution

CONTEXT.—

The pathogenesis of primary ocular adnexal marginal zone lymphoma (POAMZL) remains unclear. The reported associations with Chlamydia psittaci infection and MYD88 mutations are highly variable.

OBJECTIVE.—

To examine MYD88 L265P mutation in ocular marginal zone lymphomas and correlate with clinicopathologic features and Chlamydia infection.

DESIGN.—

Presence of MYD88 L265P mutation and Chlamydia infection in lymphoma was analyzed by using sensitive polymerase chain reaction (PCR) methods.

RESULTS.—

The MYD88 L265P mutation was identified in 8 of 22 POAMZLs (36%), including 2 of 3 cases in which PCR failed to detect clonal IGH gene rearrangement; none of the 4 secondary marginal zone lymphomas were positive. Test results for Chlamydia were negative in all cases. Patients with and without the MYD88 mutation had similar clinicopathologic features.

CONCLUSIONS.—

The MYD88 mutational analysis provides important information in diagnostic workup of POAMZL. The frequent MYD88 mutation suggests a critical role of this aberration in the pathogenesis of POAMZL and may serve as a therapeutic target for patients with progressive disease.

Recurrent mutations in NF-κB pathway components, KMT2D, and NOTCH1/2 in ocular adnexal MALT-type marginal zone lymphomas

The pathogenesis of ocular adnexal marginal zone lymphomas of mucosa-associated lymphatic tissue-type (OAML) is still poorly understood. We analyzed 63 cases of such lymphomas for non-synonymous mutations in 24 candidate genes by amplicon sequencing. We validated frequent mutations in the NF-κB regulators MYD88, TNFAIP3 and TNIP1 in OAML, but also identified recurrent mutations in several additional components of the NF-κB pathway, including BCL10 and NFKBIA. Overall, 60% of cases had mutations in at least one component of NF-κB signaling, pointing to a central role of its genetic deregulation in OAML pathogenesis. Mutations in NOTCH1 and NOTCH2 were each found in 8% of cases, indicating a pathogenetic function of these factors in OAML. KMT2D was identified as the first epigenetic regulator with mutations in OAML, being mutated in 22% of cases. Mutations in MYD88 were associated with an inferior disease-free survival. Overall, we identified here highly recurrent genetic lesions in components of the NF-κB pathway, of NOTCH1 and NOTCH2 as well as KMT2D in OAML and thereby provide major novel insights into the pathogenesis of this B cell malignancy.

Extranodal Marginal Zone B-cell Lymphoma of the Ocular Adnexa

BACKGROUND

Low-grade B-cell lymphomas located around the eye present unique challenges in diagnosis and treatment. Extranodal marginal zone B-cell lymphoma is the most common lymphoma of the ocular adnexa (conjunctiva, orbit, lacrimal gland, and eyelid).

METHODS

A systematic search of the relevant literature was performed. Material pertinent to the diagnosis, prognosis, pathogenesis, and treatment of extranodal marginal zone B-cell lymphoma of the ocular adnexa was identified, reviewed, and analyzed, focusing on management strategies for primary localized disease.

RESULTS

The primary cause of extranodal marginal zone B-cell lymphoma of the ocular adnexa remains elusive, although an infectious agent is suspected. Radiotherapy is the most common initial treatment for localized disease. Initial treatment with chemotherapy, immunotherapy, and antibiotics has shown promising results, but the number of series is limited and controlled trials do not exist.

CONCLUSIONS

Although the long-term outcome of localized extranodal marginal zone B-cell lymphoma of the ocular adnexa is good, optimal treatment remains a goal. The variation in rates of local and systemic relapse among treated stage 1E tumors suggests that critical factors affecting outcomes are not fully understood. Radiotherapy is the standard of care; at this time, the evidence is insufficient to recommend chemotherapy, immunotherapy, or antibiotics for initial treatment of extranodal marginal zone B-cell lymphoma localized to the ocular adnexa. Well-controlled comparative studies are needed.

Comprehensive genomic profiling of orbital and ocular adnexal lymphomas identifies frequent alterations in MYD88 and chromatin modifiers: new routes to targeted therapies

Non-Hodgkin lymphoma of the orbit and ocular adnexa is the most common primary orbital malignancy. Treatments for low- (extra-nodal marginal zone and follicular lymphomas) and high-grade (diffuse large B-cell lymphoma) are associated with local and vision-threatening toxicities. High-grade lymphomas relapse frequently and exhibit poor survival rates. Despite advances in genomic profiling and precision medicine, orbital and ocular adnexal lymphomas remain poorly characterized molecularly. We performed targeted next-generation sequencing (NGS) profiling of 38 formalin-fixed, paraffin-embedded orbital and ocular adnexal lymphomas obtained from a single-center using a panel targeting near-term, clinically relevant genes. Potentially actionable mutations and copy number alterations were prioritized based on gain- and loss-of-function analyses, and catalogued, approved, and investigational therapies. Of 36 informative samples, including marginal zone lymphomas (n=20), follicular lymphomas (n=9), and diffuse large B-cell lymphomas (n=7), 53% harbored a prioritized alteration (median=1, range 0-5/sample). MYD88 was the most frequently altered gene in our cohort, with potentially clinically relevant hotspot gain-of-function mutations identified in 71% of diffuse large B-cell lymphomas and 25% of marginal zone lymphomas. Prioritized alterations in epigenetic modulators were common and included gain-of-function EZH2 and loss-of-function ARID1A mutations (14% of diffuse large B-cell lymphomas and 22% of follicular lymphomas contained alterations in each of these two genes). Single prioritized alterations were also identified in the histone methyltransferases KMT2B (follicular lymphoma) and KMT3B (diffuse large B-cell lymphoma). Loss-of-function mutations and copy number alterations in the tumor suppressors TP53 (diffuse large B-cell and follicular lymphoma), CDKN2A (diffuse large B-cell and marginal zone lymphoma), PTEN (diffuse large B-cell lymphoma), ATM (diffuse large B-cell lymphoma), and NF1 (diffuse large B-cell lymphoma), and gain-of-function mutations in the oncogenes HRAS (follicular lymphoma) and NRAS (diffuse large B-cell lymphoma) were also observed. Together, our study demonstrates that NGS can be used to profile routine formalin-fixed, paraffin-embedded orbital and ocular adnexal lymphomas for identification of somatic-driving alterations and nomination of potential therapeutic strategies.

Clinicopathologic characteristics and treatment of marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma)

Extranodal marginal zone lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma) accounts for 7% to 8% of newly diagnosed lymphomas. Because of its association with infectious causes, such as Helicobacter pylori (HP) or Chlamydophila psittaci (CP), and autoimmune diseases, it has become the paradigm of an antigen-driven malignancy. MALT lymphoma usually displays an indolent course, and watch-and-wait strategies are justified initially in a certain percentage of patients. In patients with gastric MALT lymphoma or ocular adnexal MALT lymphoma, antibiotic therapy against HP or CP, respectively, is the first-line management of choice, resulting in lymphoma response rates from 75% to 80% after HP eradication and from 33% to 65% after antibiotic therapy for CP. In patients who have localized disease that is refractory to antibiotics, radiation is widely applied in various centers with excellent local control, whereas systemic therapies are increasingly being applied, at least in Europe, because of the potentially systemic nature of the disease. Therefore, the objective of this review is to briefly summarize the clinicopathologic characteristics of this distinct type of lymphoma along with current data on management strategies.

The role of infectious agents, antibiotics, and antiviral therapy in the treatment of extranodal marginal zone lymphoma and other low-grade lymphomas

OPINION STATEMENT

There is strong evidence to corroborate the association with Helicobacter pylori (Hp) to gastric extranodal marginal zone lymphoma (ENMZL) and hepatitis C virus (HCV) to splenic/nodal marginal zone lymphoma. Koch's postulates generally hold for these two associations and eradication of the infectious agent is well supported. Hp eradication (HPE) is recommended as front-line therapy for early stage gastric ENMZL regardless of Hp status. Complete response (CR) rate for Hp-negative patients is not as high as for Hp-positive patients; however, the benign nature of HPE and high rates of salvage allow this strategy to be safe while sparing some Hp-negative patients from systemic therapy or radiation. Similarly for HCV-seropositive patients, treatment with antivirals should be strongly considered as first-line for those who do not require immediate cytoreductive therapy or at some point even after completing chemoimmunotherapy. The controversy regarding the role for antibiotics is greatest for primary ocular adnexal lymphoma (POAL). Considering the low incidence of Chlamydia psittaci (Cp) infection with OAL and the challenges to reliably identifying Cp, we typically do not consider doxycycline in POAL treatment. Involved-field radiotherapy (IFRT) remains the treatment of choice for most with unilateral POAL. However, if reliable detection of Cp is available and Cp is identified, patients with unilateral low tumor stage POAL who do not require immediate radiotherapy could be considered for doxycycline as front-line treatment. Other infectious associations to indolent lymphomas have been made, including Borrelia borgdorferi (Bb) in cutaneous lymphoma and Campylobacter in immunoproliferative small intestinal disease (IPSID), but these associations are not as strong and primary treatment targeting the infectious agents is not recommended.

The many faces of small B cell lymphomas with plasmacytic differentiation and the contribution of MYD88 testing

Plasmacytic differentiation may occur in almost all small B cell lymphomas (SBLs), although it varies from being uniformly present (as in lymphoplasmacytic lymphoma (LPL)) to very uncommon (as in mantle cell lymphomas (MCLs)). The discovery of MYD88 L265P mutations in the vast majority of LPLs has had a major impact on the study of these lymphomas. Review of the cases contributed to the 2014 European Association for Haematopathology/Society for Hematopathology slide workshop illustrated how mutational testing has helped refine the diagnostic criteria for LPL, emphasizing the importance of identifying a clonal monotonous lymphoplasmacytic population and highlighting how LPL can still be diagnosed with extensive nodal architectural effacement, very subtle plasmacytic differentiation, follicular colonization, or uncommon phenotypes such as CD5 or CD10 expression. MYD88 L265P mutations were found in 11/11 LPL cases versus only 2 of 28 other SBLs included in its differential diagnosis. Mutational testing also helped to exclude other cases that would have been considered LPL in the past. The workshop also highlighted how plasmacytic differentiation can occur in chronic lymphocytic leukemia/small lymphocytic lymphoma, follicular lymphoma, SOX11 negative MCL, and particularly in marginal zone lymphomas, all of which can cause diagnostic confusion with LPL. The cases also highlighted the difficulty in distinguishing lymphomas with marked plasmacytic differentiation from plasma cell neoplasms. Some SBLs with plasmacytic differentiation can be associated with amyloid, other immunoglobulin deposition, or crystal-storing histiocytosis, which may obscure the underlying neoplasm. Finally, although generally indolent, LPL may transform, with the workshop cases suggesting a role for TP53 abnormalities.

Clinicopathologic Study of Chromosomal Aberrations in Ocular Adnexal Lymphomas of Korean Patients

Purpose

The incidence and clinical correlation of MALT1 translocation and chromosomal numerical aberrations in Korean patients with ocular adnexal mucosa associated lymphoid tissue (MALT) lymphoma have not yet been reported. We investigated the incidence and clinicopathologic relationship of these chromosomal aberrations in ocular adnexal MALT lymphomas in a Korean population.

Methods

Thirty ocular adnexal MALT lymphomas were investigated for the t(11;18) API2-MALT1, t(14;18) IgH-MALT1 translocations and chromosomes 3 and 18 aneuploidies using fluorescence in situ hybridization. Patient medical records were reviewed retrospectively for information on demographics and clinical characteristics, including treatment response.

Results

The MALT1 gene rearrangement was found in one out of 30 cases. The t(14;18) IgH-MALT1 translocation was demonstrated in only one case (3.3%), and the t(11;18) API2-MALT1 translocation was not found in any of the cases. Trisomy 3 was observed in three ocular adnexal MALT lymphomas (10.0%), and five cases showed trisomy 18 (16.7%). Translocation positive cases also showed trisomy 18. One case of tumor relapse showed trisomy 18 only in the recurrent biopsies. There were no statistically significant correlations between chromosomal aberrations and clinical characteristics and treatment responses.

Conclusions

Translocations involving the MALT1 gene are not common in Korean ocular adnexal MALT lymphomas. The t(14;18) translocation was detected in only one out of 30 cases, and the t(11;18) translocation was not found at all. Furthermore, the chromosomal aberrations found in this study had no prognostic implications.

[Persisting lesion of the conjunctiva. A masquerade syndrome?]

A 26-year-old female patient was referred because of a persisting swelling and redness of the conjunctiva for 4 months accompanied by pruritus. An ultrasound biomicroscopy showed hypoechogenic structures separated by multiple hyperechogenic septa. A biopsy was performed which revealed a marginal B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) type. A generalized lymphatic disease could be excluded by positron emission tomography-computed tomography (PET-CT). In agreement with the patient an extensive excision was performed followed by a wait and see strategy including close monitoring by ophthalmological and general internist control examinations.

Extranodal hematopoietic neoplasms and mimics in the head and neck: an update

The head and neck region is a common site for extranodal lymphomas, second only to the gastrointestinal tract; and 12% to 15% of all head and neck tumors are lymphomas. Non-Hodgkin lymphomas are most common, and Hodgkin lymphoma occurs rarely at extranodal sites in the head and neck. Most non-Hodgkin lymphomas of the head and neck region are of B-cell lineage, and the Waldeyer ring is the most common site. Head and neck lymphomas have distinctive epidemiological and clinicopathologic features, including an association with immunosuppression, infectious organisms, or autoimmune disorders; site-specific differences (eg, thyroid gland versus ocular adnexa) for common lymphomas, such as extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue; and genetic differences that provide insights into etiology. Furthermore, the diagnosis of non-Hodgkin lymphomas at extranodal sites implies differences in prognosis and therapeutic implications with lymphomas at nodal sites. In this review, we discuss various types of non-Hodgkin lymphomas and Hodgkin lymphoma, focusing on unique aspects related to the head and neck region. We also discuss a number of newer entities that are clinically indolent as well as mimics of lymphoma that can occur in the head and neck region, including infectious mononucleosis, Kikuchi-Fujimoto disease, Kimura disease, Castleman disease, and immunoglobulin G4-related disease.

Malignant lymphoma of the conjunctiva

Conjunctival lymphomas constitute 25% of all ocular adnexal lymphomas. The majority are B-cell non-Hodgkin lymphomas (NHLs) (98%), whereas conjunctival T-cell NHLs are rare (2%). The most frequent subtype of conjunctival B-cell lymphoma is extranodal marginal zone lymphoma (EMZL; 81%), followed by follicular lymphoma (8%), diffuse large B-cell lymphoma (3%), and mantle cell lymphoma (3%). Extranodal marginal zone lymphoma occurs slightly more often in women and, along with follicular lymphoma, presents late in the seventh decade of life, whereas diffuse large B-cell lymphoma and especially mantle cell lymphoma have a predilection for the male gender and typically present in the eighth decade. Extranodal marginal zone lymphoma and follicular lymphoma present most frequently in the forniceal and bulbar conjunctiva. Conjunctival diffuse large B-cell lymphoma, mantle cell lymphoma and T-cell NHLs are characterized by a short duration of symptoms before the first ophthalmologic consultation. External beam radiotherapy is the treatment of choice for extranodal marginal zone lymphoma and follicular lymphoma, whereas diffuse large B-cell lymphoma, mantle cell lymphoma, and T-cell NHLs are mainly treated with chemotherapy. Conjunctival T-cell NHLs are associated with a particularly poor prognosis, with 50% of patients having progression or recurrence during a 1-year follow-up period.

Primary fallopian tube carcinoma arising in the setting of chronic pelvic inflammatory disease

Primary fallopian tube cancer (PFTC) is a rare gynaecological malignancy, clinically often mistaken for pelvic inflammatory disease or ovarian cancer. Three primary fallopian tube carcinomas, arising in a background of chronic pelvic inflammatory disease (PID), are presented. The possible association between chronic PID and PFTC is discussed and a hypothesies linking these cancers with chronic inflammation is proposed.

Clinical characteristics of 95 patients with ocular adnexal and uveal lymphoma: treatment outcomes in extranodal marginal zone subtype

BACKGROUND

Lymphoma rarely presents in the ocular adnexa but is usually extranodal marginal zone (ENMZ) lymphoma when it does. Involved-field radiotherapy (IFRT) is the standard of care for unilateral disease, but the optimal management of more extensive disease is unclear.

PATIENTS AND METHODS

We retrospectively evaluated the clinical characteristics and outcomes of 95 patients with ocular adnexal lymphoma (OAL) or uveal lymphoma treated or diagnosed at our institution. All patients identified were included in the risk factor analysis for progression-free survival (PFS). The initial treatment-related outcomes were assessed for ENMZ OAL only (n = 62).

RESULTS

With a median follow-up of 32 months, significant risk factors for PFS after initial treatment were age (hazard ratio, 1.33; 95% confidence interval, 1.02-1.74), female gender (hazard ratio, 2.04; 95% confidence interval, 1.04-4.00), and a history of lymphoma (hazard ratio, 2.31; 95% confidence interval, 1.12-4.78). In ENMZ, IFRT was associated with improved PFS (median, 5.4 years; P < .001). Progression occurred in 7 of 39 (23%), with 6 of the 7 (86%) at systemic sites. Single-agent rituximab was typically used for bilateral ocular or systemic presentations of ENMZ OAL. Progression occurred in 7 of 11 (64%), with no progression at systemic sites. All progression events in those initially treated with rituximab occurred in the ocular adnexa.

CONCLUSION

The results of the present study have confirmed IFRT as the standard for unilateral ENMZ OAL. Single-agent rituximab was an effective agent for bilateral ocular or systemic ENMZ OAL, particularly for systemic control, but ocular progression should be closely monitored. Combined modality therapy should be studied further in bilateral and systemic ENMZ OAL.

Molecular and genomic aberrations in Chlamydophila psittaci negative ocular adnexal marginal zone lymphomas

The etiology and pathogenesis of ocular adnexal extranodal marginal zone lymphoma (OAEMZL) are still unknown and the association with Chlamydophila psittaci (C. psittaci) has been shown in only some geographic regions. Herein, we comprehensively examined the frequency of chromosomal translocations as well as CARD11, MYD88 (L265P), and A20 mutations/deletions in 45 C. psittaci negative OAEMZLs. t(14;18)(q32;q21) IGH-MALT1 and t(11;18)(q21;q21) API2-MALT1 were not detected in any of the analyzed tumors while three tumors harbored IGH translocations to an unidentified partner. CARD11 mutations were not found in all analyzed tumors, while the MYD88 L265P mutation was detected in three (6.7%) tumors. A20 mutations and deletions were each detected in seven (15.6%) and six (13.3%) tumors, respectively. Therefore, the observed genetic aberrations could account for the activation of the nuclear factor (NF)-kB signaling pathway in only a minority of the cases. Further studies are needed to identify the molecular mechanisms underlying the pathogenesis of OAEMZL.

Gamma heavy-chain disease: defining the spectrum of associated lymphoproliferative disorders through analysis of 13 cases

Gamma heavy-chain disease (gHCD) is defined as a lymphoplasmacytic neoplasm that produces an abnormally truncated immunoglobulin gamma heavy-chain protein that lacks associated light chains. There is scant information in the literature regarding the morphologic findings in this rare disorder, but cases have often been reported to resemble lymphoplasmacytic lymphoma (LPL). To clarify the spectrum of lymphoproliferative disorders that may be associated with gHCD, this study reports the clinical, morphologic, and phenotypic findings in 13 cases of gHCD involving lymph nodes (n=7), spleen (n=2), bone marrow (n=8), or other extranodal tissue biopsies (n=3). Clinically, patients showed a female predominance (85%) with frequent occurrence of autoimmune disease (69%). Histologically, 8 cases (61%) contained a morphologically similar neoplasm of small lymphocytes, plasmacytoid lymphocytes, and plasma cells that was difficult to classify with certainty, whereas the remaining 5 cases (39%) showed the typical features of one of several other well-defined entities in the 2008 WHO classification. This report demonstrates that gHCD is associated with a variety of underlying lymphoproliferative disorders but most often shows features that overlap with cases previously reported as "vaguely nodular, polymorphous" LPL. These findings also provide practical guidance for the routine evaluation of small B-cell neoplasms with plasmacytic differentiation that could represent a heavy-chain disease and give suggestions for an improved approach to the WHO classification of gHCD.

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.

Marginal zone lymphomas with plasmacytic differentiation and related disorders

Marginal zone lymphomas of all types (nodal, splenic, and extranodal mucosa-associated lymphoid tissue [MALT]) may show plasmacytic differentiation. Distinguishing marginal zone lymphomas from other small B-cell lymphomas with plasmacytic differentiation, especially lymphoplasmacytic lymphoma, or from plasma cell neoplasms may be challenging. Marginal zone lymphomas with plasmacytic differentiation were discussed in 2 sessions of the 2009 Society for Hematopathology/European Association for Haematopathology Workshop. Session 4 focused on nodal marginal zone lymphomas, including cases exhibiting classic features and cases displaying atypical phenotypes. The difficulties of classification of cases with increased numbers of large cells were also discussed. Session 5 examined nonnodal marginal zone lymphomas and related entities, including splenic marginal zone lymphoma, MALT lymphoma, γ heavy chain disease, and cryoglobulin-associated lymphoproliferative disorders. These cases illustrate the importance of clinical data and, in some cases, phenotypic and cytogenetic findings in appropriately applying the 2008 World Health Organization criteria.

Bilateral conjunctival extranodal marginal zone B-cell lymphoma

Extranodal marginal zone B-cell lymphomas (EMZLs), while relatively common in adults, are rare entities in the pediatric population. A subclass of the typically aggressive non-Hodgkin lymphomas, the few reported pediatric cases indicate that, as in adults, these tumors tend to be indolent. We present a case of EMZL arising in the conjunctivae in a 9-year-old male with bilateral disease. The patient was treated with surgical excision alone and has remained disease-free 6 years after the operation.

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.

Follicular lymphomas with plasmacytic differentiation include two subtypes

Follicular lymphomas with plasmacytic differentiation were described more than two decades ago. However, the possibility that some of these reported cases are marginal zone lymphomas or composite lymphomas must be considered. In addition, it is also uncertain whether follicular lymphomas with plasmacytic differentiation have any unique cytogenetic or other features. Therefore, fluorescence immunophenotypic and interphase cytogenetic analysis of 14 well-characterized follicular lymphomas with plasmacytic differentiation was performed using a CD138 antibody to identify the plasma cells and with BCL2, BCL6, IGH@ and MALT1 break-apart probes and a chromosome 12 centromeric probe. CD10 was expressed in 12/14 cases, BCL6 in 12/12 cases and BCL2 in 12/14 cases. At least one cytogenetic abnormality was identified in 12/14 cases. The same abnormality was present in both the plasmacytic (CD138+) and non-plasmacytic (CD138-) component in all 10 evaluable cases. BCL2 rearrangements were present in seven cases (5 IGH@ rearranged, 1 IGH@-not rearranged, 1 IGH@-not evaluable), BCL6 rearrangement in two (1 also with BCL2/IGH@ rearrangement), +12 in 1, +MALT1 without +18 in 1, IGH@ rearrangement without other abnormalities in 1 and IGH@ rearranged or partially deleted in 1 case. No cases showed +BCL6 (3q27) or a MALT1 rearrangement. All six cases with an isolated BCL2 rearrangement had predominantly interfollicular plasmacytic cells whereas, 6/7 cases without the translocation had concentrations of intrafollicular or perifollicular plasmacytic cells (P<0.005), as did the case with BCL2 and BCL6 translocations. These results support the existence of bona fide follicular lymphomas with plasmacytic differentiation and support the clonal relationship of the neoplastic lymphoid and plasma cells in at least most of these cases. The differential distribution of the plasma cells, specifically in relation to the presence or absence of an isolated BCL2 rearrangement suggests that the latter cases may be distinctive, sharing some features with marginal zone lymphomas.

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.

A TNM-Based Clinical Staging System of Ocular Adnexal Lymphomas

Context.—The ocular adnexal lymphomas (OAL) arise in the conjunctiva, orbit, lacrimal gland, and eyelids. To date, they have been clinically staged using the Ann Arbor staging system, first designed for Hodgkin and later for nodal, non–Hodgkin lymphoma. The Ann Arbor system has several shortcomings, particularly when staging extranodal non– Hodgkin lymphomas, such as OAL, which show different dissemination patterns from nodal lymphomas.

Objective.—To describe the first TNM-based clinical staging system for OAL.

Design.—Retrospective literature review.

Results.—We have developed, to our knowledge, the first American Joint Committee on Cancer–International Union Against Cancer TNM-based staging system for OAL to overcome the limitations of the Ann Arbor system. Our staging system defines disease extent more precisely within the various anatomic compartments of the ocular adnexa and allows for analysis of site-specific factors not addressed previously. It aims to facilitate future studies by identifying clinical and histomorphologic features of prognostic significance. This system is for primary OAL only and is not intended for intraocular lymphomas.

Conclusions.—Our TNM-based staging system for OAL is a user-friendly, anatomic documentation of disease extent, which creates a common language for multicenter and international collaboration. Data points will be collected with the aim of identifying biomarkers to be incorporated into the staging system.