Vitreous diagnosis in neoplastic diseases

Indications and pathologic diagnoses of diagnostic chorioretinal biopsies in the province of Quebec, Canada

OBJECTIVE

To review the clinical usefulness of chorioretinal biopsies in diagnostically undefined cases of intraocular inflammation or chorioretinal lesions.

DESIGN

Retrospective case series.

PARTICIPANTS

Seven patients who underwent chorioretinal biopsies.

METHODS

This case series included all consecutive patients who underwent chorioretinal biopsies in 2 academic tertiary care centres in the province of Quebec between 2014 and 2020.

RESULTS

A total of 7 patients were included in the study. Five patients with intraocular inflammation underwent chorioretinal biopsies to rule out an infectious or neoplastic etiology, whereas 2 patients underwent biopsies for suspicion of neoplastic chorioretinal masses. Final diagnoses included primary chorioretinal lymphoma (n = 2), toxoplasmosis (n = 1), benign choroidal mass (n = 1), nonnecrotizing granuloma (n = 1), and peripheral exudative hemorrhagic chorioretinopathy (n = 1). No specific diagnosis was defined in 1 case of panuveitis with scleritis. No postoperative complications were reported.

CONCLUSIONS

Chorioretinal biopsies clarified the diagnosis in 6 of 7 patients, including a definitive diagnosis of lymphoma in 2 patients. This is a high rate of diagnosis that also represents clinically meaningful results that influence management. Future directions include identifying patients in whom adjuvant chorioretinal biopsy would yield a high rate of diagnosis.

Vitreoretinal Lymphoma: Optimizing Diagnostic Yield and Accuracy

PURPOSE

To determine whether the addition of adjunctive tests, including immunohistochemistry (IHC), cytokine analysis, flow cytometry, and IgH gene rearrangement testing, achieves improved diagnostic parameters compared with cytologic smears alone in the detection of vitreoretinal lymphoma (VRL). To determine which of these tests or combination of tests provide the greatest diagnostic utility.

DESIGN

Retrospective review to assess diagnostic value.

METHODS

This single university-affiliated tertiary care center study included data from 237 vitreous biopsies performed between 1999 and 2017 in patients with suspected VRL. From 1999 to 2008-2009, cytologic smears were the sole test performed (84 cases). The protocol initiated in 2008-2009 added the 4 additional diagnostic tests (153 cases). The sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy, and diagnostic yield were calculated. Parameters were calculated for tests individually, for all 5 combined, and all possible 2-, 3-, and 4-test combinations. For cytologic smears, diagnostic parameters were calculated both before and after the addition of adjunctive tests to our protocol and for the entire cohort.

RESULTS

Of the 237 vitreous biopsies, 50 samples (21%) were from patients with confirmed central nervous system lymphoma and/or actively treated central nervous system, systemic, or intraocular lymphoma. Diagnostic yields (95% CI) were 90% (85%-93%) for smears, 82% (72%-89%) for IHC, 91% (85%-96%) for cytokine analysis, 76% (67%-84%) for IgH gene rearrangement, and 50% (40%-60%) for flow cytometry. For smears, the sensitivity pre-protocol was 73% (39%-94%), compared with 87% (69%-96%) post-protocol. IgH gene rearrangement was the only test exhibiting low sensitivity (40%). The combination of smears, IHC, and cytokine analysis exhibited the highest diagnostic parameters, with sensitivity 92%, specificity 98%, and diagnostic yield 100%.

CONCLUSIONS

The combination of cytologic smears, IHC, and cytokine analysis seems to be a reasonable and sufficient protocol for the diagnosis of suspected VRL. IgH gene rearrangement and flow cytometry may be the most expendable tests from our protocol.

Integrative Biology of Diabetic Retinal Disease: Lessons from Diabetic Kidney Disease

Diabetic retinal disease (DRD) remains the most common cause of vision loss in adults of working age. Progress on the development of new therapies for DRD has been limited by the complexity of the human eye, which constrains the utility of traditional research techniques, including animal and tissue culture models-a problem shared by those in the field of kidney disease research. By contrast, significant progress in the study of diabetic kidney disease (DKD) has resulted from the successful employment of systems biology approaches. Systems biology is widely used to comprehensively understand complex human diseases through the unbiased integration of genetic, environmental, and phenotypic aspects of the disease with the functional and structural manifestations of the disease. The application of a systems biology approach to DRD may help to clarify the molecular basis of the disease and its progression. Acquiring this type of information might enable the development of personalized treatment approaches, with the goal of discovering new therapies targeted to an individual's specific DRD pathophysiology and phenotype. Furthermore, recent efforts have revealed shared and distinct pathways and molecular targets of DRD and DKD, highlighting the complex pathophysiology of these diseases and raising the possibility of therapeutics beneficial to both organs. The objective of this review is to survey the current understanding of DRD pathophysiology and to demonstrate the investigative approaches currently applied to DKD that could promote a more thorough understanding of the structure, function, and progression of DRD.

Upregulation of Lysyl Oxidase Expression in Vitreous of Diabetic Subjects: Implications for Diabetic Retinopathy

Animal studies have shown diabetes-induced lysyl oxidase (LOX) upregulation promotes blood-retinal-barrier breakdown and retinal vascular cell loss associated with diabetic retinopathy (DR). However, it is unclear whether changes in LOX expression contribute to the development and progression of DR. To determine if vitreous LOX levels are altered in patients with DR, 31 vitreous specimens from subjects with advanced proliferative DR (PDR), and 27 from non-diabetics were examined. The two groups were age- and gender-matched (57 ± 12 yrs vs. 53 ± 18 yrs; 19 males and 12 females vs. 17 males and 10 females). Vitreous samples obtained during vitrectomy were assessed for LOX levels using ELISA. LOX was detected in a larger number of PDR subjects (58%) than in non-diabetic subjects (15%). Additionally, ELISA measurements showed a significant increase in LOX levels in the diabetic subjects with PDR, compared to those of non-diabetic subjects (68.3 ± 112 ng/mL vs. 2.1 ± 8.2 ng/mL; p < 0.01). No gender difference in vitreous LOX levels was observed in either the diabetic or non-diabetic groups. Findings support previous reports of increased LOX levels in retinas of diabetic animals and in retinal vascular cells in high glucose condition, raising the prospect of targeting LOX overexpression as a potential target for PDR treatment.

[Diagnostics and treatment of primary vitreoretinal lymphoma]

BACKGROUND

Primary vitreoretinal lymphoma (PVRL) is a rare ocular lymphoid malignancy, mostly a diffuse large B-cell lymphoma. The PVRL, previously called primary intraocular lymphoma (PIOL), is a subset of primary central nervous system lymphoma (PCNSL).

DIAGNOSIS

The diagnosis of PVRL is often difficult as it often mimics chronic intermediate or posterior uveitis; therefore, PVRL requires various procedures for the diagnostics, e.g. immunohistochemistry, cytology, pathology, molecular pathology and cytokine analysis (interleukin 10) after surgically obtaining ocular specimens.

THERAPY

Treatment forms that are effective for systemic lymphomas have not been reliably successful for PVRL and PCNSL. Current management of PVRL consists of chemotherapy, such as methotrexate or rituximab, possibly combined with external beam radiation whereby both chemotherapeutic agents are administered systemically as well as intravitreally. Intravitreal treatment alone is recommended solely in the case of monocular PVRL, which is highly controversial. A PVRL usually responds well to initial treatment; however, relapse rates and CNS involvement are high, resulting in a poor prognosis and limited survival.

Patients with diffuse uveitis and inactive toxoplasmic retinitis lesions test PCR positive for Toxoplasma gondii in their vitreous and blood

BACKGROUND/AIMS

To determine if patients with inactive chorioretinitis lesions who experience chronic toxoplasmic uveitis test PCR positive for Toxoplasma in their ocular fluids.

METHODS

Two patients undergoing long-term anti-toxoplasmic treatment developed chronic uveitis and vitritis. They underwent therapeutic and diagnostic pars plana vitrectomy. Patient specimens were tested for toxoplasmosis by real-time PCR and nested PCR. Patient specimens were also tested for the presence of Toxoplasma antibodies that recognise allelic peptide motifs to determine parasite serotype.

RESULTS

Patients tested positive for Toxoplasma by real-time PCR at the B1 gene in the vitreous and aqueous humours of patient 1, but only the vitreous of patient 2. Patients were not parasitemic by real-time PCR in plasma and blood. During surgery, only old hyperpigmented toxoplasmic scars were observed; there was no sign of active retinitis. Multilocus PCR-DNA sequence genotyping at B1, NTS2 and SAG1 loci established that two different non-archetypal Toxoplasma strains had infected patients 1 and 2. A peptide-based serotyping ELISA confirmed the molecular findings.

CONCLUSIONS

No active lesions were observed, but both patients possessed sufficient parasite DNA in their vitreous to permit genotyping. Several hypotheses to explain the persistence of the vitritis and anterior uveitis in the absence of active retinitis are discussed.

Current concepts in diagnosing and managing primary vitreoretinal (intraocular) lymphoma

Primary vitreoretinal lymphoma (PVRL), previously called primary intraocular lymphoma (PIOL), is a rare and fatal ocular malignancy. PVRL is a subset of primary central nervous system lymphoma (PCNSL), mostly a diffuse large B-cell lymphoma. The diagnosis of PVRL is often challenging as it often masquerades as chronic uveitis. PVRL requires invasive procedures for tissue diagnosis. Cytology/pathology, molecular pathology (immuno-globulin or T-cell receptor gene rearrangement), immunohistochemistry, biophysical technology (flow cytometry), and cytokine analysis (interleukine-10) are often required. The therapies that have been successful in systemic lymphomas have not been reliably effective in PVRL and PCNSL. Current management of PVRL involves aggressive chemotherapy (methotrexate and rituximab) and radiation therapy. PVRL normally responds well to initial treatment; however, relapse rate and CNS involvement are high, resulting in poor prognosis and limited survival. A professional team of medical experts in ophthalmology, oncology (particularly neuro-oncology), and pathology is essential for optimizing patient management.