The elusive nature of primary intraocular lymphoma

AN ELDERLY PATIENT WITH ACUTE TRANSIENT OUTER RETINAL DISRUPTION RESEMBLING BILATERAL MULTIPLE EVANESCENT WHITE DOT SYNDROME

PURPOSE

To report an unusual case of an elderly patient with transient outer retinal disruption resembling bilateral multiple evanescent white dot syndrome.

METHODS

Observational case report. Fundus photographs, fluorescein angiography, standard and ultra-widefield fundus autofluorescence, and cross-sectional and en face optical coherence tomography were used to characterize and describe the clinical findings.

RESULTS

A 67-year-old woman presented with decreased vision and floaters in her left eye. Best-corrected visual acuity was 20/20-3 in the right eye and 20/80-2 in the left eye. Funduscopic examination showed small deep white dots and foveal granularity of the left eye corresponding to hyperautofluorescent spots on fundus autofluorescence and ellipsoid zone disruption on spectral domain optical coherence tomography. The asymptomatic right eye had evidence of subretinal deposits on spectral domain optical coherence tomography but was otherwise unremarkable. At 4-week follow-up, the patient noted resolution of her symptoms in the left eye but had developed floaters and blurry vision in her right eye. The left eye showed resolving white spots and ellipsoid zone disruption. However, the right eye had new evidence of white spots corresponding to hyperautofluorescent spots on fundus autofluorescence. Spectral domain optical coherence tomography demonstrated subretinal deposits overlying areas of ellipsoid zone disruption. At 8-week follow-up, the patient was asymptomatic in both eyes with best-corrected visual acuity of 20/20 in both eyes. The hyperautofluorescent spots on ultra-widefield fundus autofluorescence had faded with restoration of ellipsoid zone disruption in both eyes and disappearance of subretinal deposits.

CONCLUSION

Our case demonstrates multimodal retinal imaging findings resembling multiple evanescent white dot syndrome in an elderly patient. The bilateral presentation, presence of subretinal deposits before symptom onset, and older age of the patient were atypical features for this entity.

Intraocular Biopsy and ImmunoMolecular Pathology for "Unmasking" Intraocular Inflammatory Diseases

Intraocular inflammation can hide a variety of eye pathologies. In 33% of cases, to obtain a correct diagnosis, investigation of the intraocular sample is necessary. The combined analyses of the intraocular biopsy, using immuno-pathology and molecular biology, point to resolve the diagnostic dilemmas in those cases where history, clinical tests, and ophthalmic and systemic examinations are inconclusive. In such situations, the teamwork between the ophthalmologist and the molecular pathologist is critically important to discriminate between autoimmune diseases, infections, and intraocular tumors, including lymphoma and metastases, especially in those clinical settings known as masquerade syndromes. This comprehensive review focuses on the diagnostic use of intraocular biopsy and highlights its potential to enhance research in the field. It describes the different surgical techniques of obtaining the biopsy, risks, and complication rates. The review is organized according to the anatomical site of the sample: I. anterior chamber containing aqueous humor, II. iris and ciliary body, III. vitreous, and IV. choroid and retina. We have excluded the literature concerning biopsy for choroidal melanoma and retinoblastoma, as this is a specialized area more relevant to ocular oncology.

Multi-modal imaging and anatomic classification of the white dot syndromes

The white dot syndromes (WDS) are a diverse group of posterior uveitidies that share similar clinical findings but are unique from one another. Multimodal imaging has allowed us to better understand the morphology, the activity and age of lesions, and whether there is CNV associated with these different ocular pathologies. The “white dot syndromes” and their uveitic masqueraders can now be anatomically categorized based on lesion localization. The categories include local uveitic syndromes with choroidal pathology, systemic uveitic syndromes with choroidal pathology, and multifocal choroiditis with outer retinal/choriocapillaris pathology with uveitis and without uveitis. Neoplastic and infectious etiologies are also discussed given their ability to masquerade as WDS.

Primary intraocular lymphoma

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.

Intraocular lymphoma diagnosed by fine-needle aspiration biopsy

PURPOSE

To describe clinical experience in the diagnosis of intraocular lymphoma by fine-needle aspiration biopsy (FNAB) in patients with one or more discrete intraocular infiltrative lesions and limited or absent intravitreal tumour cells.

METHODS

 Retrospective descriptive analysis of patients who underwent intraocular FNAB of a solid retinal, subretinal pigment epithelial or uveal tumour that proved to be a malignant lymphoma.

RESULTS

After exclusions, our study group consisted of seven patients, each of whom had one or more discrete intraocular infiltrative lesions and limited or absent intravitreal tumour cells and underwent a diagnostic intraocular FNAB that confirmed malignant intraocular lymphoma cytopathologically. These included three patients with one or more geographic yellow subretinal pigment epithelial infiltrates and one patient each with a prominent nodular white subretinal pigment epithelial tumour, a rapidly developing solid placoid choroidal mass, a haemorrhagic retinal infiltrative lesion and an infiltrative iris tumour, respectively. A prominent feature of virtually all aspirates was a large proportion of degenerated lymphoid cells in the background. Cytologically intact tumour cells ranged from relatively homogeneous small round cells with large nucleus to cytoplasm ratio to pleomorphic large cells with irregular knob-like nuclear protrusions. Immunocytochemical stains for lymphoid markers were helpful in confirming the pathological diagnosis of lymphoma in the five patients in whom this testing was performed.

CONCLUSION

FNAB was a useful diagnostic tool in the described subgroup of patients with suspected intraocular lymphoma. FNAB should be considered as a diagnostic option in selected patients with suspected intraocular lymphoma, especially if there are few or no vitreous cells.

Eradication of tumor colonization and invasion by a B cell-specific immunotoxin in a murine model for human primary intraocular lymphoma

Human primary intraocular lymphoma (PIOL) is predominantly a B cell-originated malignant disease with no appropriate animal models and effective therapies available. This study aimed to establish a mouse model to closely mimic human B-cell PIOL and to test the therapeutic potential of a recently developed immunotoxin targeting human B-cell lymphomas. Human B-cell lymphoma cells were intravitreally injected into severe combined immunodeficient mice. The resemblance of this tumor model to human PIOL was examined by fundoscopy, histopathology, immunohistochemistry, and evaluated for molecular markers. The therapeutic effectiveness of immunotoxin HA22 was tested by injecting the drug intravitreally. Results showed that the murine model resembles human PIOL closely. Pathologic examination revealed that the tumor cells initially colonized on the retinal surface, followed by infiltrating through the retinal layers, expanding preferentially in the subretinal space, and eventually penetrating through the retinal pigment epithelium into the choroid. Several putative molecular markers for human PIOL were expressed in vivo in this model. Tumor metastasis into the central nervous system was also observed. A single intravitreal injection of immunotoxin HA22 after the establishment of the PIOL resulted in complete regression of the tumor. This is the first report of a murine model that closely mimics human B-cell PIOL. This model may be a valuable tool in understanding the molecular pathogenesis of human PIOL and for the evaluation of new therapeutic approaches. The results of B cell-specific immunotoxin therapy may have clinical implications in treating human PIOL.