title: Primary intraocular lymphoma.
abstract: Primary intraocular lymphoma (PIOL) is an ocular malignancy that is a subset of primary central system lymphoma (PCNSL). Approximately one-third of PIOL patients will have concurrent PCNSL at presentation, and 42-92% will develop PCNSL within a mean of 8-29 months. Although rare, the incidence has been rising in both immunocompromised and immunocompetent populations. The majority of PIOL is diffuse large B-cell lymphoma, though rare T-cell variants are described. Recently, PIOL has been classified by main site of involvement in the eye, with vitreoretinal lymphoma as the most common type of ocular lymphoma related to PCNSL. Diagnosis remains challenging for ophthalmologists and pathologists. PIOL can masquerade as noninfectious or infectious uveitis, white dot syndromes, or occasionally as other neoplasms such as metastatic cancers. Laboratory diagnosis by cytology has been much aided by the use of immunocytochemistry, flow cytometry, biochemical finding of interleukin changes (IL10:IL6 ratio > 1), and cellular microdissection with polymerase chain reaction amplification for clonality. Use of several tests improves the diagnostic yield. Approaches to treatment have centered on systemic methotrexate-based chemotherapy, often with cytarabine (Ara-C) and radiotherapy. Use of intravitreal chemotherapy with methotrexate (0.4 mg/0.1 mL) is promising in controlling ocular disease, and intravitreal rituximab (anti-CD20 monoclonal antibody) has also been tried. Despite these advances, prognosis remains poor.
authors.affiliation: UCL Institute of Ophthalmology, London, UK; Moorfields Eye Hospital, London, UK; Department of Ophthalmology, St Bartholomew's Hospital, London, UK. Electronic address: mandeep.sagoo@moorfields.nhs.uk.
authors.forename: Mandeep S
authors.initials: MS
authors.lastname: Sagoo
authors.affiliation: Moorfields Eye Hospital, London, UK.
authors.forename: Hemal
authors.initials: H
authors.lastname: Mehta
authors.affiliation: Department of Ophthalmology, St Bartholomew's Hospital, London, UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Swampillai
authors.affiliation: Moorfields Eye Hospital, London, UK; Department of Ophthalmology, St Bartholomew's Hospital, London, UK.
authors.forename: Victoria M L
authors.initials: VM
authors.lastname: Cohen
authors.affiliation: UCL Institute of Ophthalmology, London, UK.
authors.forename: Sepideh Z
authors.initials: SZ
authors.lastname: Amin
authors.affiliation: Department of Oncology, St Bartholomew's Hospital, London, UK.
authors.forename: P Nicholas
authors.initials: PN
authors.lastname: Plowman
authors.affiliation: UCL Institute of Ophthalmology, London, UK; Moorfields Eye Hospital, London, UK.
authors.forename: Sue
authors.initials: S
authors.lastname: Lightman
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D003941:Diagnostic Techniques, Ophthalmological; D006801:Humans; D064090:Intraocular Lymphoma / Q000175:diagnosis / Q000188:drug therapy; D058449:Intravitreal Injections
chemical_list: D000970:Antineoplastic Agents
keywords: lymphoma; masquerade; ocular; vitreoretinal