CHOROIDAL TUMOR BIOPSY: A Review of the Current State and a Glance Into Future Techniques

Diagnostic Confirmation of Choroidal Lymphoma by Anterior Chamber Paracentesis and Aqueous Fluid Flow Cytometry

PURPOSE

To report the clinical course of patients with diagnostic confirmation of choroidal lymphoma by anterior chamber paracentesis and aqueous fluid flow cytometry.

METHODS

Single-center case series.

RESULTS

Two patients with choroidal thickening were suspected to have choroidal lymphoma based on clinical findings and ultrasonographic evidence of extrascleral extension. In each case, anterior chamber paracentesis was performed due to the observation of the associated anterior chamber reaction. Flow cytometry detected the presence of a clonal B-cell population consistent with non-Hodgkin's lymphoma. In one case, external beam radiation therapy resulted in a complete therapeutic response. More invasive methods of ocular tissue biopsy were avoided.

CONCLUSIONS

Definitive diagnosis in suspected cases of choroidal lymphoma remains challenging. Ocular fluid sampling may be a low morbidity and convenient alternative for confirming a suspected diagnosis in cases associated with cellular infiltration of the intraocular fluids.

Using Deep Learning to Distinguish Highly Malignant Uveal Melanoma from Benign Choroidal Nevi

Background: This study aimed to evaluate the potential of human-machine interaction (HMI) in a deep learning software for discerning the malignancy of choroidal melanocytic lesions based on fundus photographs. Methods: The study enrolled individuals diagnosed with a choroidal melanocytic lesion at a tertiary clinic between 2011 and 2023, resulting in a cohort of 762 eligible cases. A deep learning-based assistant integrated into the software underwent training using a dataset comprising 762 color fundus photographs (CFPs) of choroidal lesions captured by various fundus cameras. The dataset was categorized into benign nevi, untreated choroidal melanomas, and irradiated choroidal melanomas. The reference standard for evaluation was established by retinal specialists using multimodal imaging. Trinary and binary models were trained, and their classification performance was evaluated on a test set consisting of 100 independent images. The discriminative performance of deep learning models was evaluated based on accuracy, recall, and specificity. Results: The final accuracy rates on the independent test set for multi-class and binary (benign vs. malignant) classification were 84.8% and 90.9%, respectively. Recall and specificity ranged from 0.85 to 0.90 and 0.91 to 0.92, respectively. The mean area under the curve (AUC) values were 0.96 and 0.99, respectively. Optimal discriminative performance was observed in binary classification with the incorporation of a single imaging modality, achieving an accuracy of 95.8%. Conclusions: The deep learning models demonstrated commendable performance in distinguishing the malignancy of choroidal lesions. The software exhibits promise for resource-efficient and cost-effective pre-stratification.

Cross-Platform Identification and Validation of Uveal Melanoma Vitreous Protein Biomarkers

Purpose

The purpose of this study was to profile protein expression liquid vitreous biopsies from patients with uveal melanoma (UM) using mass spectrometry to identify prognostic biomarkers, signaling pathways, and therapeutic targets.

Methods

Vitreous biopsies were collected from two cohorts in a pilot study: comparative control eyes with epiretinal membranes (ERM; n = 3) and test eyes with UM (n = 8). Samples were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Identified proteins were compared to data from a targeted multiplex ELISA proteomics platform.

Results

A total of 69 significantly elevated proteins were detected in the UM vitreous, including LYVE-1. LC-MS/MS identified 62 significantly upregulated proteins in UM vitreous that were not previously identified by ELISA. Analysis of differential protein expression by tumor molecular classification (gene expression profiling [GEP] and preferentially expressed antigen in melanoma [PRAME]) further identified proteins that correlated with these classifications. Patients with high-risk GEP tumors displayed elevated vitreous expression of HGFR (fold-change [FC] = 2.66E + 03, P value = 0.003) and PYGL (FC = 1.02E + 04, P = 1.72E-08). Patients with PRAME positive tumors displayed elevated vitreous expression of ENPP-2 (FC = 3.21, P = 0.04), NEO1 (FC = 2.65E + 03, P = 0.002), and LRP1 (FC = 5.59E + 02, P value = 0.01). IGF regulatory effectors were highly represented (P value = 1.74E-16). Cross-platform analysis validated seven proteins identified by ELISA and LC-MS/MS.

Conclusions

Proteomic analysis of liquid biopsies may provide prognostic information supporting gene expression of tumor biopsies. The use of multiple protein detection platforms in the same patient samples increases the sensitivity of candidate biomarker detection and allows for precise characterization of the vitreous proteome.

Displacement of submacular hemorrhage with intravitreal tissue plasminogen activator following 27 gauge transvitreal fine needle aspiration biopsy for choroidal melanoma

Purpose

To describe the management of submacular hemorrhage (SMH), a vision threatening complication following transvitreal choroidal biopsy, with intravitreal tissue plasminogen activator (tPA) and pure perfluoropropane (C₃F₈) gas bubble injection.

Observations

A 53 year old female with choroidal melanoma of the left eye underwent iodine-125 plaque brachytherapy placement and 27 gauge transvitreal fine needle aspiration choroidal biopsy for gene expression profiling. On postoperative day 2, large SMH was identified on dilated fundus examination. At the time of plaque brachytherapy removal, intravitreal tPA and pure C₃F₈ gas bubble injection with post operative positioning was also performed to attempt displacement of SMH. At postoperative month 1 following tPA and gas bubble displacement, the SMH was completely displaced inferotemporally outside of the macula and visual acuity improved from 20/70 at postoperative week 1 to 20/25 at postoperative month 1.

Conclusions and importance

Subretinal hemorrhage can be a complication of transvitreal choroidal tumor biopsy but early detection and prompt treatment can result in good visual outcomes.

Biopsy for molecular risk stratification in uveal melanoma: Yields and molecular characteristics in 119 patients

BACKGROUND

Prognostic cytological and molecular features of uveal melanoma have been well researched and are essential in management. Samples can be obtained in vivo through fine needle aspirate biopsy, vitrector cutter, forceps or post-enucleation for off-site testing. This study aims to examine cytological and chromosome microarray yields of these samples.

METHODS

A retrospective cohort analysis of 119 uveal melanoma biopsies submitted to our laboratory. Samples included those taken in vivo (n = 57) and post-enucleation (n = 62). Patient and tumour features were collected including age, sex, primary tumour location, basal diameter and tumour height. Prognostic outcomes measured include cell morphology, chromosomal status and immunohistochemistry.

RESULTS

Post-enucleation biopsies accounted for just over half of our samples (52%). Post-enucleation samples had a more successful genetic yield than in vivo biopsies (77% vs. 50%, p = 0.04) though there was no difference for cytological yields. There was no difference in cytological or microarray yields between instruments. The vitrector biopsy group had the smallest tumour thickness (5 mm vs. 10 mm [fine-needle aspirate biopsy], p = 0.003). There was a strong correlation between monosomy 3, BAP1 aberrancy and epithelioid cell type in post-enucleation samples (Tb  = 0.742, p = 0.005). However, epithelioid morphology was not associated with either monosomy 3 (p = 0.07) or BAP1 aberrancy (p = 0.24) for in vivo biopsies.

CONCLUSIONS

All three biopsy instruments provide similar cytological yields as post-enucleation sampling, although post-enucleation samples had a more successful chromosome microarray yield. Epithelioid cytomorphology alone is insufficient for prognostication in in vivo biopsies, immunohistochemistry would be a useful surrogate test.

Photoacoustic Imaging of Enucleated Eyes from Patients with Uveal Melanoma can Reveal Extrascleral Growth

Background:

Uveal melanoma is treated by either enucleation (removal of the eye) or local eye-sparing therapies, depending on tumor size and whether there are signs of extrascleral growth. Photoacoustic (PA) imaging is a novel imaging modality that provides high-resolution images of the molecular composition of tissues.

Objective:

In this study, the feasibility of PA imaging for uveal melanomas and detection of extrascleral growth was explored.

Methods:

Seven enucleated human eyes with uveal melanomas were examined using PA imaging. The spectral signatures of the melanomas and the layers of the normal eyewall were characterized using 59 excitation wavelengths from 680 to 970 nm.

Results:

Significant differences were seen between the spectra obtained from melanoma and the healthy eyewall. Using spectral unmixing, melanin, hemoglobin and collagen could be mapped out, showing the architecture of the tumor in relation to the eyewall. This allowed visualization of regions where the tumor extended into the extrascleral space.

Conclusion:

PA imaging appears to have the potential to aid in assessing uveal melanomas and as a diagnostic tool for the detection of extrascleral growth.

Vitrectomy-Assisted Biopsy: An in vitro Study on the Impact of Cut Rate and Probe Size

Purpose

The aim of this study was to optimize the technique of performing vitrectomy-assisted biopsy of intraocular tumors by comparing the cytohistological findings in specimens obtained with different vitrectomy probes and cut rates.

Methods

Vitrectomy-assisted biopsies were taken from a fresh porcine liver. For each sampling, the vacuum level was 300 mm Hg. The following parameters were compared; cut rate (60, 600 and 6,000 cuts per minute [cpm]), probe type (standard and two-dimensional cutting [TDC]), and probe diameter (23-gauge and 25-gauge). The specimens were assessed by automated whole-slide imaging analysis and conventional light microscopy.

Results

Seventy-two biopsies were analyzed for the number of hepatocytes, total area of tissue fragments, and total stained area of each microscope slide. For all probe types, these parameters were significantly and positively correlated with the cut rate. TDC probes led to significantly higher scores than those of standard probes, independent of the cut rate. There were no significant differences in results when using 23-gauge or 25-gauge standard probes. Light microscopic examination demonstrated well-preserved cells sufficient for cytohistological analyses in all investigated cases.

Conclusions

The higher the cut rate, the larger is the amount of aspirated cellular material. There were no significant differences between 23-gauge and 25-gauge biopsies. Cut rates up to 6,000 cpm did not adversely affect the cytohistological features of the samples.

Fine-Needle Aspiration Biopsy of Intraocular Mass-Like Lesions

OBJECTIVES

The purpose of this study was to evaluate the diagnostic performance of fine-needle aspiration (FNA) biopsy for intraocular mass-like lesions and its contributing factors.

METHODS

Intraocular FNA cases were retrieved and reviewed along with histopathologic follow-ups, if available. The effects of rapid on-site evaluation (ROSE), repeated biopsy, and adjunct immunocytochemical studies on cytologic diagnoses were analyzed.

RESULTS

Of 72 FNA biopsies from 63 patients, nondiagnostic biopsy was seen in 17 cases (24%), whereas a definitive diagnosis was rendered in 39 cases (54%). The cytologic diagnoses correlated well with histopathologic follow-ups with a concordance rate of 61%. Almost all nondiagnostic biopsies (16/17, 94%) were seen in cases in which ROSE was not performed. Of the 7 patients in whom biopsy was repeated, a definitive diagnosis was rendered in 4 cases (57%). Immunocytochemistry was performed in the majority of cases with a malignant diagnosis, especially in metastatic tumors (75%).

CONCLUSIONS

Our data demonstrates that FNA is an effective tool for the diagnosis of intraocular tumors. ROSE, repeated biopsy, and adjunct immunocytochemistry can help reduce the nondiagnostic rate and/or enhance diagnosis of malignancy, further improving FNA diagnostic performance.

Multiple Uveal Melanoma

Introduction

Multiple uveal melanoma is a rare occurrence and includes bilateral melanoma, unilateral multiple/multifocal melanoma, or melanoma with metastasis to the ipsilateral or contralateral eye.

Methods

A chart review of patients diagnosed with uveal melanoma between January 2013 and January 2019 at the Duke University Eye Center Ophthalmic Oncology Service was performed.

Results

Three patients with multiple, sequential melanoma were identified; patient 1 had bilateral choroidal melanoma and patients 2 and 3 had 2 choroidal melanomas occurring in the same eye. In all 3 patients, both the first and sequential choroidal melanomas were treated with I-125 radioactive plaque brachytherapy (PBT). Two patients were found to have developed secondary metastatic uveal melanoma as a presenting sign of systemic metastases. Patient 4, initially treated with PBT, was diagnosed with ipsilateral metastatic choroidal melanoma, also treated with PBT. Patient 5 had right eye enucleation for choroidal melanoma and developed vision-threatening metastasis in the left eye, which was treated with PBRT. None of the patients had history of cancer prior to their first diagnosis. Patients 1 and 5 were tested with a systemic melanoma panel; both were negative for BAP1, but patient 1 had a variant of unknown significance in BRCA2. Patient 3 had oculodermal melanocytosis, an established risk factor of uveal melanoma.

Conclusion

Although rare, the possibility of multiple uveal melanoma does exist. Examination of the treated and contralateral eye on a regular basis is crucial, not only to identify local failure but also new metastases from the primary tumor and additional primary tumors.

Not every pigmented tumour is melanoma: Adenoma of the ciliary body pigment epithelium

Differential diagnosis between a melanoma and a pseudomelanoma requires many years of experience and ocular studies, and requires paying attention to the smallest details. The case is presented of a 57 year-old male with an adenoma of the ciliary body pigment epithelium that was treated with an enucleation of the eye due to a suspicion of a choroidal melanoma.

Response Evaluation of Choroidal Melanoma After Brachytherapy Using Diffusion-Weighted Magnetic Resonance Imaging (DW-MRI): Preliminary Findings

Purpose: To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MRI) in the assessment of therapeutic response in patients with choroidal melanoma treated with brachytherapy.

Materials and Methods: We performed a prospective, unicentric study which included patients with choroidal melanoma and indication for brachytherapy. Three DW-MRI examinations were proposed for each patient, one before and two after treatment. The apparent diffusion coefficient (ADC) value was calculated on DW-MRI and compared with local tumor control assessed by ophthalmologic follow-up.

Results: From 07/2018 to 06/2019, 19 patients were recruited, 13 of whom underwent follow-up examinations. Patients' ages ranged from 24 to 78 years and 52.9% were male. At the ocular ultrasound, the mean tumor thickness and diameter were 6.3 and 11.5 mm, respectively. Two patients (15.4%) showed signs of tumor progression during follow-up (7 and 9 months after treatment). There was no statistically significant difference in tumor size between MR before and after treatment, however, there was a significant reduction in mean ADC in patients with progression (p = 0.02).

Conclusion: DW-MRI is a promising method for monitoring patients with choroidal melanoma; reduction in the mean ADC values between pre-treatment MRI and the first post-treatment MRI may be related to the lack of response to brachytherapy and increased risk of disease progression.

Multi-center analysis of intraocular biopsy technique and outcomes for uveal melanoma: Ocular Oncology Study Consortium report 4

PURPOSE

To investigate the relationship between surgical approach for intraocular tumor biopsy of uveal melanoma and tumor morphologic features such as size and intraocular location and the effect of these variables on diagnostic yield and biopsy outcome.

METHODS

Consecutive patients from nine Ocular Oncology centers with uveal melanoma (UM) undergoing tumor biopsy immediately preceding I125 plaque brachytherapy with tissue sent for gene expression profiling (GEP) testing were reviewed retrospectively.

RESULTS

Three hundred sixty patients were included (50% men, mean age 60.2 years). Overall biopsy yield was 99% and 83% for GEP and cytopathology, respectively. Surgeon choice of biopsy approach (trans-vitreal vs. trans-scleral) was found to associate with both tumor location and tumor thickness. A trans-scleral rather than trans-vitreal approach was used more commonly for anteriorly located tumors (92% vs. 38% of posterior tumors, p < 0.001) and thicker tumors (86% vs. 55% of thin tumors, p < 0.001). When performing trans-vitreal biopsies, ocular oncologists with previous vitreoretinal surgery fellowship training were more likely to use wide-field surgical viewing systems, compared with indirect ophthalmoscopy (82.6% vs. 20.6%, p < 0.001). Surgical complications were rare and occurred more frequently with trans-vitreal biopsies (3.6% vs. 0.46%, p = 0.046).

CONCLUSIONS

In this multi-center analysis of UM tumor biopsy, surgical yield was high for obtaining tumor tissue for GEP and cytopathology analysis with both trans-scleral and trans-vitreal techniques. Fellowship-trained ocular oncologists' preferred intraocular biopsy techniques associated strongly with tumor location, tumor thickness, and fellowship training of the surgeon. Short-term complication rates were low.

Uveal Melanoma Biopsy: A Review

Intraocular tumor diagnosis is based on clinical findings supported by additional imaging tools, such as ultrasound, optical coherence tomography and angiographic techniques, usually without the need for invasive procedures or tissue sampling. Despite improvements in the local treatment of uveal melanoma (UM), the prevention and treatment of the metastatic disease remain unsolved, and nearly 50% of patients develop liver metastasis. The current model suggests that tumor cells have already spread by the time of diagnosis, remaining dormant until there are favorable conditions. Tumor sampling procedures at the time of primary tumor diagnosis/treatment are therefore now commonly performed, usually not to confirm the diagnosis of UM, but to obtain a tissue sample for prognostication, to assess patient's specific metastatic risk. Moreover, several studies are ongoing to identify genes specific to UM tumorigenesis, leading to several potential targeted therapeutic strategies. Genetic information can also influence the surveillance timing and metastatic screening type of patients affected by UM. In spite of the widespread use of biopsies in general surgical practice, in ophthalmic oncology the indications and contraindications for tumor biopsy continue to be under debate. The purpose of this review paper is to critically evaluate the role of uveal melanoma biopsy in ophthalmic oncology.

Primary Choroidal Lymphoma Diagnosed with 27-Gauge Pars Plana Vitrectomy Choroidal Biopsy

Background

Currently, transvitreal fine-needle aspiration biopsy is the most widely used tissue biopsy technique in cases of suspected intraocular lymphoma due to its relative simplicity and low trauma. The small sample produced, however, may be inadequate for diagnostic and prognostic analyses due to mechanical artefacts, insufficient material, or sampling errors. Small case series have demonstrated choroidal biopsy via vitrectomy to be safe and effective. With smaller-gauge vitrectomy instruments, visual recovery is rapid, and post-operative inflammation and conjunctival scarring is minimised. Furthermore, smaller-gauge instrumentation does not appear to affect the diagnostic yield of biopsies for intraocular lymphoma in vitro. We report a case of primary choroidal lymphoma successfully diagnosed with 27-gauge pars plana vitrectomy choroidal biopsy.

Case Presentation

A 72-year-old female presented with a 6-month history of painless blurred vision in her right eye. Fundus examination revealed a large pale choroidal mass centred on the posterior pole with overlying exudative retinal detachment. Enhanced depth imaging optical coherence tomography revealed a markedly thickened choroid with an undulating appearance. B-scan ultrasonography demonstrated diffuse, smooth thickening of the choroid, and retrobulbar extrascleral hypoechoic nodules. A 27-gauge pars plana vitrectomy was performed and choroidal biopsy taken. Histopathologic, immunohistochemical, and flow cytometry studies confirmed a diagnosis of extranodal marginal zone B-cell lymphoma. Systemic workup found no evidence of systemic lymphoma. As such, the patient was diagnosed with primary choroidal lymphoma. She underwent intensity-modulated external beam radiotherapy with subsequent resolution of disease.

Conclusions

Primary choroidal lymphoma can be safely and effectively diagnosed via 27-gauge vitrectomy choroidal biopsy.

Progression of vascular changes in macular telangiectasia type 2: comparison between SD-OCT and OCT angiography

PURPOSE

To investigate the different appearances of vascular changes in macular telangiectasia type 2 (MacTel) and to describe their possible progression, the vascular patterns in different retinal layers were analyzed with optical coherence tomography angiography (OCT-A) and the findings were correlated with a spectral-domain OCT (SD-OCT) disease severity scale based on the extent of ellipsoid zone (EZ) loss.

METHODS

Participants from the MacTel Study Group in Muenster and a healthy cohort were investigated with OCT-A using RTVue XR Avanti. After segmentation of the superficial capillary network, the deep capillary network, and the outer retina (OR), flow density was analyzed using Optovue software. Then, the images were exported using the software Fiji (National Institute of Mental Health, Bethesda, MD, USA) and analyzed with the automated MATLAB program (Mathworks, Version R2014b). Four parameters (total vessel length, number of vessel branches, number of vessel segments, and fractal dimension) were examined on the vascular skeletons (temporal, foveal, nasal, and total fields of the ETDRS grid). In addition, linear and area measurements of EZ loss were performed on SD-OCT volume scans. Progression characteristics and correlation between linear and area measurements were analyzed using linear mixed effects models.

RESULTS

Twenty eyes of healthy probands (20 OCT-A and 20 SD-OCT scans) and 122 eyes of 61 MacTel patients were included. In order to classify the severity of the disease, MacTel eyes were assigned to a SD-OCT "disease severity scale" (grade 1 = no EZ loss; grade 2 = EZ loss temporal to the fovea; grade 3 = EZ loss including the fovea and the region nasal to the fovea). Flow density and total vessel length showed only limited differences between healthy eyes and different grades of MacTel, but particularly the numbers of branches and vessel segments, as well as the fractal dimension values, demonstrated significant and progressive reduction in the superficial and deep capillary networks of the temporal, nasal, and total ETDRS fields. Moreover, the outer retina showed a progressive presence of hyperreflective material in SD-OCT grades 2 and 3 eyes with associated vascular patterns in the OR on OCT-A.

CONCLUSIONS

In SD-OCT, the severity of MacTel is characterized by progressive EZ loss, which may be used as a simple clinical "disease severity scale". In addition, OCT-A enables visualization and quantification of vascular patterns with mathematical methods. The morphological progression of the disease correlated significantly with progressive vascular changes, especially in respect of the numbers of branches and vessel segments as well as fractal dimension. This suggests that the severity of neurodegenerative and neurovascular changes develops in parallel and that the analysis and quantification of the vascular changes in the superficial and deep capillary networks may become an additional parameter for future treatment trials. Moreover, the significant association between hyperreflective material progressively visible on SD-OCT in the OR, which most often contains vessels in OCT-A, and advancing SD-OCT severity grades, as well as vascular changes in OCT-A, supports the concept of retinal neovascularization in the OR in patients with advanced MacTel.