The Genetic Profile of Large B-Cell Lymphomas Presenting in the Ocular Adnexa.

To provide insights into targetable oncogenic pathways, this retrospective cohort study investigated the genetic profile of 26 patients with diffuse large B-cell lymphoma, not otherwise specified (DLBCL-NOS), and two patients with high-grade B-cell lymphoma with MYC and BCL2 rearrangements (HGBCL) presenting in the ocular adnexa. Pathogenic variants and copy number variations in 128 B-cell lymphoma-relevant genes were analyzed by targeted next-generation sequencing. Genetic subtypes were determined with the LymphGen algorithm. Primary ocular adnexal DLBCL-NOS constituted 50% (n = 14) and was generally characterized by non-germinal center B-cell origin (non-GCB) (n = 8, 57%), and LymphGen MCD subtype (n = 5, 36%). Primary ocular adnexal DLBCL-NOS presented pathogenic variants in genes involved in NF-κB activation and genes which are recurrently mutated in other extranodal lymphomas of non-GCB origin, including MYD88 (n = 4, 29%), CD79B (n = 3, 21%), PIM1 (n = 3, 21%), and TBL1XR1 (n = 3, 21%). Relapsed DLBCL-NOS presenting in the ocular adnexa (n = 6) were all of non-GCB origin and frequently of MCD subtype (n = 3, 50%), presenting with a similar genetic profile as primary ocular adnexal DLBCL-NOS. These results provide valuable insights into genetic drivers in ocular adnexal DLBCL-NOS, offering potential applications in future precision medicine.

Prevalence and prognostic value of MYD88 and CD79B mutations in ocular adnexal large B-cell lymphoma: a reclassification of ocular adnexal large B-cell lymphoma.

AIMS: To (1) reclassify ocular adnexal large B-cell lymphomas (OA-LBCLs) per 2016 WHO lymphoma classification and (2) determine the prevalence of MYD88 and CD79B mutations and their association with clinical parameters among OA-LBCLs. METHODS: This study is a retrospective analysis of all OA-LBCLs diagnosed in Denmark between 1980 and 2018. Medical records and tissue samples were retrieved. Thirty-four OA-LBCLs were included. Fluorescence in situ hybridisation and Epstein-Barr-encoded RNA in situ hybridisation were used for the reclassification. Mutational status was established by allele-specific PCR and confirmed by Sanger sequencing. Primary endpoints were overall survival, disease-specific survival (DSS) and progression-free survival (PFS). RESULTS: Two LBCL subtypes were identified: diffuse large B-cell lymphoma (DLBCL) (27 of 32; 84%) and high-grade B-cell lymphoma (HGBL) with MYC and BCL2 and/or BCL6 rearrangements (5 of 32; 16%). cMYC/BCL2 double-expressor DLBCLs had a poorer DSS than non-double-expressor DLBCLs (5-year DSS, 25% vs 78%) (HR 0.23; 95% CI 0.06 to 0.85; p=0.014). MYD88 mutations were present in 10 (29%) of 34 lymphomas and carried a poorer PFS than wild-type cases (5-year PFS, 0% vs 43%) (HR 0.78; 95% CI 0.61 to 0.98; p=0.039). CD79B mutations were present in 3 (9%) of 34 cases. CONCLUSION: OA-LBCL consists mainly of two subtypes: DLBCL and HGBL with MYC and BCL2 and/or BCL6 rearrangements. MYD88 mutations are important drivers of OA-LBCL. MYD88 mutations, as well as cMYC/BCL2 double-expressor DLBCL, appear to be associated with a poor prognosis. Implementing MYD88 mutational analysis in routine diagnostics may improve OA-LBCL prognostication.

Specific location of ocular adnexal lymphoma and mortality: an international multicentre retrospective study.

AIMS: To examine whether the specific location of ocular adnexal lymphoma (OAL) and the American Joint Committee on Cancer (AJCC) TNM tumour stage are prognostic factors for mortality in the main OAL subtypes. METHODS: Clinical and survival data were retrospectively collected from seven international eye cancer centres. All patients from 1980 to 2017 with histologically verified primary or secondary OAL were included. Cox regression was used to compare the ocular adnexal tumour locations on all-cause mortality and disease-specific mortality. RESULTS: OAL was identified in 1168 patients. The most frequent lymphoma subtypes were extranodal marginal zone B-cell lymphoma (EMZL) (n=688, 59%); follicular lymphoma (FL) (n=150, 13%); diffuse large B-cell lymphoma (DLBCL) (n=131, 11%); and mantle cell lymphoma (MCL) (n=89, 8%). AJCC/TNM tumour-stage (T-stage) was significantly associated with disease-specific mortality in primary ocular adnexal EMZL and increased through T-categories from T1 to T3 disease. No associations between AJCC/TNM T-stage and mortality were found in primary ocular adnexal FL, DLBCL, or MCL. EMZL located in the eyelid had a significantly increased disease-specific mortality compared with orbital and conjunctival EMZL, in both primary EMZL and the full EMZL cohort. In DLBCL, eyelid location had a significantly higher disease-specific mortality compared with an orbital or lacrimal gland location. CONCLUSION: Disease-specific mortality is associated with AJCC/TNM T-stage in primary ocular adnexal EMZL patients. Lymphoma of the eyelid has the highest disease-specific mortality in primary EMZL, and in the full cohort of EMZL and DLBCL patients.

Ocular adnexal lymphoma: Subtype-specific clinical and genetic features.

Ocular adnexal lymphoma is a relatively rare disease but is one of the most common malignancies in the ocular adnexa, and its incidence is steadily increasing. Ocular adnexal lymphoma consists mainly of four histopathological subtypes of non-Hodgkin B-cell lymphoma: extranodal marginal zone lymphoma (EMZL), follicular lymphoma (FL), mantle cell lymphoma (MCL) and large B-cell lymphoma (LBCL). The clinical characteristics associated with each of the subtypes are not well known due to the sparsity of cases. Furthermore, a number of molecular and phenotypic features have been identified as recurrent and prognosticating in LBCL but are not yet well documented for the ocular adnexal region: concurrent MYC and BCL2 and/or BCL6 rearrangements, MYC/BCL2 double-expressor phenotype (in diffuse large B-cell lymphomas), and MYD88 and CD79B mutations. Therefore, the present PhD study aimed to investigate the clinical features of (1) conjunctival lymphoma by subtype and (2) ocular adnexal MCL in an international multicentre cohort of 307 patients and (3) the clinical and genetic features of ocular adnexal LBCL in 34 Danish patients. This was performed by collecting clinical data on the patients and tissue samples of the LBCLs. The tissue samples were analysed immunohistochemically for phenotype, by allele-specific PCR and Sanger sequencing for the presence of the mutations, and by fluorescence in situ hybridisation for the rearrangements. Statistical analyses were performed to detect correlations with clinical features and survival. The analyses revealed that conjunctival EMZL and FL typically presented in individuals in their 60s as localised unilateral tumour masses and had favourable prognoses (5-year disease-specific survival: 82%-97%). LBCL and MCL were found in all the ocular adnexal structures, with the orbit being the most common location (82% and 58%, respectively). These lymphomas typically presented in patients in their 70s, with MCL having a male predominance. MCLs commonly presented with bilateral lesions and systemic involvement, while LBCLs were unilateral localised tumours. Both subtypes had poor prognoses, with 49%-62% of patients having succumbed to the disease within 5 years. Ocular adnexal LBCLs had presence of concurrent MYC and BCL2 and/or BCL6 rearrangements in 16% of cases, MYC/BCL2 double-expressor phenotype in 44% of diffuse large B-cell lymphomas, and MYD88 ± CD79B mutations in 29% of cases. MYC/BCL2 double-expressor phenotype and MYD88 mutations were associated with adverse prognoses. All in all, the results indicate that the histopathological subtype of ocular adnexal lymphoma is a major outcome predictor. Furthermore, the results underline the importance of analysing the expression of MYC and BCL2 by immunohistochemistry in diffuse large B-cell lymphoma patients and advocate for incorporating the analysis of MYD88 mutations in the routine diagnostic workup of ocular adnexal LBCL. SUMMARY IN DANISH: Lymfomer i øjenregionen (orbita, conjunctiva, øjenlåg, tårekirtel og tåresaek) er relativt sjaeldne tumorer, men er blandt de hyppigste cancerformer i denne region og forekomsten er hastigt stigende. Lymfomer i øjenregionen består hovedsageligt af 4 undertyper af non-Hodgkin B-celle lymfom: ekstranodalt marginal zone lymfom, follikulaert lymfom, storcellet B-celle lymfom og mantle celle lymfom. Grundet sygdommens sjaeldenhed er kliniske karakteristika ved de forskellige lymfomundertyper kun sparsomt undersøgt. Endvidere er der blevet identificeret en raekke prognostisk vigtige molekylaere og faenotypiske kendetegn ved storcellede B-celle lymfomer, som endnu ikke er velundersøgt i øjenregionen. Det drejer sig om samtidig rearrangement i MYC og BCL2 og/eller BCL6, samtidig overekspression af MYC og BCL2 samt MYD88 og CD79B mutationer. Dette ph.d.-studie havde derfor til formål at undersøge de kliniske kendetegn ved (1) mantle celle lymfomer i øjenregionen og (2) de forskellige undertyper af conjunktivale lymfomer i en international kohorte med 307 patienter samt (4) de kliniske, molekylaere og faenotypiske kendetegn ved storcellet B-celle lymfom i 34 danske patienter. Vaevsmaterialet med storcellede B-celle lymfomer blev undersøgt ved hjaelp af immunhistokemi for faenotypen, ved hjaelp af allel-specifik PCR og Sanger sekventering for mutationerne og ved hjaelp af fluorescens in situ-hybridisering for rearrangementerne. Der blev udført statistiske analyser med henblik på at finde eventuelle sammenhaenge med kliniske karakteristika og overlevelse. Analyserne viste, at conjunctivalt ekstranodalt marginal zone lymfom og follikulaert lymfom typisk forekom blandt patienter i 60erne som ensidige tumorer uden spredning og var forbundet med en god prognose (5-års sygdomsspecifik overlevelse på 82-97%). Storcellet B-celle lymfom og mantle celle lymfom blev fundet i samtlige strukturer i øjenregionen med orbita som den hyppigste lokalisation (hhv. 82% og 58%). Disse lymfomundertyper forekom primaert hos patienter i 70erne med overvaegt af maend blandt mantle celle lymfomerne. Mantle celle lymfomerne praesenterede sig typisk som dobbeltsidige laesioner i øjenregionen med systemisk involvering, mens storcellede B-celle lymfomer var ensidige tumorer uden spredning. Begge undertyper havde en dårlig prognose, hvor cirka halvdelen af patienterne døde af sygdommen indenfor 5 år. Genetisk var storcellede B-celle lymfomer i øjenregionen karakteriseret ved betydelig praevalens af MYD88 mutationer (29%), som var forbundet med en dårlig prognose. Rearrangementer i MYC og BCL2 og/eller BCL6 forekom i 16% af tilfaeldene. Derudover havde 44% af diffuse storcellede B-celle lymfomer samtidig overekspression af MYC og BCL2, som var associeret med en dårlig prognose for patienterne. Alt i alt viser resultaterne, at den histologiske undertype er en vigtig prognostisk faktor for lymfomer i øjenregionen. Derudover fremhaever resultaterne vigtigheden af undersøgelsen af MYC/BCL2 faenotypen og implementeringen af MYD88 mutationsundersøgelsen i rutinediagnostikken af storcellede B-celle lymfomer i øjenregionen.