Detection of neoplastic-immune hybrid cells with metastatic properties in uveal melanoma

Background

Uveal melanoma is the most common non-cutaneous melanoma and is an intraocular malignancy affecting nearly 7,000 individuals per year worldwide. Of these, approximately 50% will progress to metastatic disease for which there are currently no effective therapies. Despite advances in molecular profiling and metastatic stratification of uveal melanoma tumors, little is known regarding their underlying biology of metastasis. Our group has identified a disseminated neoplastic cell population characterized by co-expression of immune and melanoma proteins, circulating hybrid cells (hybrids), in patients with uveal melanoma. Compared to circulating tumor cells, which lack expression of immune proteins, hybrids are detected at an increased prevalence in peripheral blood and can be used as a non-invasive biomarker to predict metastatic progression.

Methods

To ascertain mechanisms underlying enhanced hybrid cell dissemination we identified hybrid cells within primary uveal melanoma tumors using single cell RNA sequencing and evaluated their gene expression and predicted ligand-receptor interactions in relation to other melanoma and immune cells within the primary tumor. We then verified expression of upregulated hybrid pathways within patient-matched tumor and peripheral blood hybrids using cyclic immunofluorescence and quantified their protein expression relative to other non-hybrid tumor and disseminated tumor cells.

Results

Among the top upregulated genes and pathways in hybrid cells were those involved in enhanced cell motility and cytoskeletal rearrangement, immune evasion, and altered cellular metabolism. In patient-matched tumor and peripheral blood, we verified gene expression by examining concordant protein expression for each pathway category: TMSB10 (cell motility), CD74 (immune evasion) and GPX1 (metabolism). Both TMSB10 and GPX1 were expressed on significantly higher numbers of disseminated hybrid cells compared to circulating tumor cells, and CD74 and GPX1 were expressed on more disseminated hybrids than tumor-resident hybrids. Lastly, we identified that hybrid cells express ligand-receptor signaling pathways implicated in promoting metastasis including GAS6-AXL, CXCL12-CXCR4, LGALS9-P4HB and IGF1-IGFR1.

Conclusion

These findings highlight the importance of TMSB10, GPX1 and CD74 for successful hybrid cell dissemination and survival in circulation. Our results contribute to the understanding of uveal melanoma tumor progression and interactions between tumor cells and immune cells in the tumor microenvironment that may promote metastasis.

Panretinal Optical Coherence Tomography

We introduce a new concept of panoramic retinal (panretinal) optical coherence tomography (OCT) imaging system with a 140° field of view (FOV). To achieve this unprecedented FOV, a contact imaging approach was used which enabled faster, more efficient, and quantitative retinal imaging with measurement of axial eye length. The utilization of the handheld panretinal OCT imaging system could allow earlier recognition of peripheral retinal disease and prevent permanent vision loss. In addition, adequate visualization of the peripheral retina has a great potential for better understanding disease mechanisms regarding the periphery. To the best of our knowledge, the panretinal OCT imaging system presented in this manuscript has the widest FOV among all the retina OCT imaging systems and offers significant values in both clinical ophthalmology and basic vision science.

Analysis of uveal melanoma scRNA sequencing data identifies neoplastic-immune hybrid cells that exhibit metastatic potential

Uveal melanoma (UM) is the most common non-cutaneous melanoma and is an intraocular malignancy that affects nearly 7,000 individuals per year worldwide. Of these, nearly 50% will progress to metastatic disease for which there are currently no effective therapies. Despite advances in the molecular profiling and metastatic stratification of class 1 and 2 UM tumors, little is known regarding the underlying biology of UM metastasis. Our group has identified a disseminated tumor cell population characterized by co-expression of immune and melanoma proteins, (circulating hybrid cells (CHCs), in patients with UM. Compared to circulating tumor cells, CHCs are detected at an increased prevalence in peripheral blood and can be used as a non-invasive biomarker to predict metastatic progression. To identify mechanisms underlying enhanced hybrid cell dissemination we sought to identify hybrid cells within a primary UM single cell RNA-seq dataset. Using rigorous doublet discrimination approaches, we identified UM hybrids and evaluated their gene expression, predicted ligand-receptor status, and cell-cell communication state in relation to other melanoma and immune cells within the primary tumor. We identified several genes and pathways upregulated in hybrid cells, including those involved in enhancing cell motility and cytoskeleton rearrangement, evading immune detection, and altering cellular metabolism. In addition, we identified that hybrid cells express ligand-receptor signaling pathways implicated in promoting cancer metastasis including IGF1-IGFR1, GAS6-AXL, LGALS9-P4HB, APP-CD74 and CXCL12-CXCR4. These results contribute to our understanding of tumor progression and interactions between tumor cells and immune cells in the UM microenvironment that may promote metastasis.

Increased Number and Severity of Open Globe Injuries during COVID-19 Stay-at-home Orders

PURPOSE

To evaluate the occurrence and outcome of open globe injury during state-mandated COVID-19 stay-at-home orders compared to historical averages at a tertiary medical center in Portland, Oregon.

METHODS

Open globe injury between January 1, 2015 and December 31, 2020 was identified using relevant procedure codes. The number of injuries, mechanism of trauma, and short-term outcomes of globes repaired during the study period of March 23, 2020 to July 6, 2020 when stay-at-home orders were in effect were compared to a cohort from the same 15-week time frame in 2015-2019. We also evaluated injuries occurring throughout 2020 as compared to the prior 5 years.

RESULTS

263 consecutive open globe injuries were identified between January 2015 and December 2020. While Oregon's stay-at-home orders were in effect, we observed a significant increase in the number of open globe injuries treated compared to the prior 5 years (p = .004). Twenty-four cases identified during the study period represent a 2-fold increase over the 2015-2019 average of 11.8 globe repairs during the same 15-week time period. Visual acuity < 20/200 at 6 months (p = .008) and secondary enucleation (p < .001) were more frequent during stay-at-home orders, and severity of injury as calculated by the Ocular Trauma Scores (OTS) was higher. Time-to-repair was similar between the two cohorts.

CONCLUSION

At our center, there was an increased number and severity of open globe injury during the period of mandatory COVID-19 stay-at-home orders. Visual acuity outcomes and risk for secondary enucleation were poorer compared to the reference cohort.Abbreviations: Ocular Trauma Score (OTS), Open globe injury (OGI), Emergency department (ED), Oregon Health and Science University (OHSU).

Psychometric Results of a New Patient-Reported Outcome Measure for Uveal Melanoma Post-Brachytherapy Treatment: The PROM-UM

The objective of this study was to evaluate the psychometric properties of a new patient-reported outcome instrument intended for use with patients who have undergone brachytherapy for uveal melanoma (PROM-UM). Classical test theory and item response theory were used to evaluate the performance of individual items and domains. A convenience sample of 439 participants who had undergone brachytherapy for uveal melanoma from one of three North American ocular oncology treatment centers were included in this cross-sectional study. Exploratory factor analysis identified three domains which were labelled "Symptom Impairment", "Worry", and "Discomfort". The acceptability of the instrument was supported by little missing data (range = 0.00-1.14%) and low maximum endorsement (range = 0.00-1.82%). Item-total (range = 0.68-0.85) and inter-item (range = 0.74-0.80) correlations indicated acceptable reliability. Discrimination and difficulty were assessed using item response theory. Items in all three domains indicated moderate to very high discrimination (range = 1.00-4.10). Two items in the Symptom Impairment domain were too difficult to measure. Response ranges in the other two domains demonstrated acceptable difficulty. These results from the study indicate that this new patient-reported outcome instrument can be used with patients treated with brachytherapy for uveal melanoma. Providers could use this instrument to help inform post-treatment management.

MRI Features for Identifying MYCN-amplified RB1 Wild-type Retinoblastoma

Background MYCN-amplified RB1 wild-type (MYCNARB1+/+) retinoblastoma is a rare but clinically important subtype of retinoblastoma due to its aggressive character and relative resistance to typical therapeutic approaches. Because biopsy is not indicated in retinoblastoma, specific MRI features might be valuable to identify children with this genetic subtype. Purpose To define the MRI phenotype of MYCNARB1+/+ retinoblastoma and evaluate the ability of qualitative MRI features to help identify this specific genetic subtype. Materials and Methods In this retrospective, multicenter, case-control study, MRI scans in children with MYCNARB1+/+ retinoblastoma and age-matched children with RB1-/- subtype retinoblastoma were included (case-control ratio, 1:4; scans acquired from June 2001 to February 2021; scans collected from May 2018 to October 2021). Patients with histopathologically confirmed unilateral retinoblastoma, genetic testing (RB1/MYCN status), and MRI scans were included. Associations between radiologist-scored imaging features and diagnosis were assessed with the Fisher exact test or Fisher-Freeman-Halton test, and Bonferroni-corrected P values were calculated. Results A total of 110 patients from 10 retinoblastoma referral centers were included: 22 children with MYCNARB1+/+ retinoblastoma and 88 control children with RB1-/- retinoblastoma. Children in the MYCNARB1+/+ group had a median age of 7.0 months (IQR, 5.0-9.0 months) (13 boys), while children in the RB1-/- group had a median age of 9.0 months (IQR, 4.6-13.4 months) (46 boys). MYCNARB1+/+ retinoblastomas were typically peripherally located (in 10 of 17 children; specificity, 97%; P < .001) and exhibited plaque or pleomorphic shape (in 20 of 22 children; specificity, 51%; P = .011) with irregular margins (in 16 of 22 children; specificity, 70%; P = .008) and extensive retina folding with vitreous enclosure (specificity, 94%; P < .001). MYCNARB1+/+ retinoblastomas showed peritumoral hemorrhage (in 17 of 21 children; specificity, 88%; P < .001), subretinal hemorrhage with a fluid-fluid level (in eight of 22 children; specificity, 95%; P = .005), and strong anterior chamber enhancement (in 13 of 21 children; specificity, 80%; P = .008). Conclusion MYCNARB1+/+ retinoblastomas show distinct MRI features that could enable early identification of these tumors. This may improve patient selection for tailored treatment in the future. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Rollins in this issue.

PSEUDOPANUVEITIS AS A HARBINGER FOR SYSTEMIC LEUKEMIA RECURRENCE

PURPOSE

To describe a patient with a history of pre-B-cell acute lymphoblastic leukemia in remission, who developed recurrent alternating intraocular leukemia manifesting with pseudohypopyon, uveal mass, and serous retinal detachment. In multiple instances, this constellation of ocular findings preceded systemic leukemia recurrence.

METHOD

Case report.

RESULTS

A 29-year-old man with a history of pre-B-cell acute lymphoblastic leukemia, in remission after a hematopoietic stem cell transplant, presented with pseudohypopyon, uveal lesions, and serous retinal detachment of the right eye. Comprehensive workup for infectious and inflammatory etiologies was unremarkable, and a bone marrow biopsy revealed systemic recurrence of leukemia. One year later, while again in remission, the patient developed a pseudohypopyon, uveal mass, and serous retinal detachment of the other eye. Repeat bone marrow biopsy showed impending leukemia relapse, which occurred 1 month later. Orbital radiation resulted in complete ocular resolution.

CONCLUSION

The constellation of pseudohypopyon, serous retinal detachment, and uveal mass (pseudopanuveitis) should be recognized as a harbinger for systemic pre-B ALL recurrence.

A multicenter analysis of nucleic acid quantification using aqueous humor liquid biopsy in retinoblastoma – Implications for clinical testing

Purpose

Retinoblastoma (RB) is most often diagnosed with clinical features and not diagnosed with tumor biopsy. This study describes tumor-derived analyte concentrations from aqueous humor (AH) liquid biopsy and its use in clinical assays.

Design

Case series study.

Participants

Sixty-two RB eyes from 55 children and 14 control eyes from 12 children from 4 medical centers.

Methods

This study included 128 RB AH samples including: diagnostic (DX) samples, samples from eyes undergoing treatment (TX), samples after completing treatment (END), and during bevacizumab injection for radiation therapy after completing RB treatment (BEV). Fourteen-control AH were analyzed for unprocessed analytes (double-stranded DNA [dsDNA], single-stranded DNA [ssDNA], micro-RNA [miRNA], RNA, and protein) with Qubit fluorescence assays. Double-stranded DNA from 2 RB AH samples underwent low-pass whole-genome sequencing to detect somatic copy number alterations. Logistic regression was used to predict disease burden given analyte concentrations.

Main Outcome Measures

Unprocessed analyte (dsDNA, ssDNA, miRNA, RNA and protein) concentrations.

Results

Results revealed dsDNA, ssDNA, miRNA, and proteins, but not RNA, were quantifiable in most samples (up to 98%) with Qubit fluorescence assays. Median dsDNA concentration was significantly higher in DX (3.08 ng/μl) compared to TX (0.18 ng/μl; P < 0.0001) at an order of 17 times greater and 20 times greater than END samples (0.15 ng/μl; P = 0.001). Using logistic regression, nucleic acid concentrations were useful in predicting higher versus lower RB disease burden. Retinoblastoma somatic copy number alterations were identified in a TX, but not in a BEV sample, indicating the correlation with RB activity.

Conclusions

Aqueous humor liquid biopsy in RB is a high-yield source of dsDNA, ssDNA, miRNA, and protein. Diagnostic samples are most useful for RB 1 gene mutational analyses. Genomic analysis may be more informative of tumor activity status than quantification alone and can be performed even with smaller analyte concentrations obtained from TX samples.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Circulating Neoplastic-Immune Hybrid Cells Predict Metastatic Progression in Uveal Melanoma

Background: Uveal melanoma is an aggressive cancer with high metastatic risk. Recently, we identified a circulating cancer cell population that co-expresses neoplastic and leukocyte antigens, termed circulating hybrid cells (CHCs). In other cancers, CHCs are more numerous and better predict oncologic outcomes compared to circulating tumor cells (CTCs). We sought to investigate the potential of CHCs as a prognostic biomarker in uveal melanoma. Methods: We isolated peripheral blood monocular cells from uveal melanoma patients at the time of primary treatment and used antibodies against leukocyte and melanoma markers to identify and enumerate CHCs and CTCs by immunocytochemistry. Results: Using a multi-marker approach to capture the heterogeneous disseminated tumor cell population, detection of CHCs was highly sensitive in uveal melanoma patients regardless of disease stage. CHCs were detected in 100% of stage I-III uveal melanoma patients (entire cohort, n = 68), whereas CTCs were detected in 58.8% of patients. CHCs were detected at levels statically higher than CTCs across all stages (p = 0.05). Moreover, CHC levels, but not CTCs, predicted 3 year progression-free survival (p < 0.03) and overall survival (p < 0.04). Conclusion: CHCs are a novel and promising prognostic biomarker in uveal melanoma.

The Global Retinoblastoma Outcome Study: a prospective, cluster-based analysis of 4064 patients from 149 countries

Background

Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival.

Methods

We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models.

Findings

The cohort included 4064 children from 149 countries. The median age at diagnosis was 23·2 months (IQR 11·0–36·5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0·8%) of 636 children from high-income countries, 55 (5·4%) of 1027 children from upper-middle-income countries, 342 (19·7%) of 1738 children from lower-middle-income countries, and 196 (42·9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98·8%) of 4064 children. The 3-year survival rate was 99·5% (95% CI 98·8–100·0) for children from high-income countries, 91·2% (89·5–93·0) for children from upper-middle-income countries, 80·3% (78·3–82·3) for children from lower-middle-income countries, and 57·3% (52·1-63·0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16·67; 95% CI 4·76–50·00), cT4 advanced tumour compared to cT1 (8·98; 4·44–18·18), and older age at diagnosis in children up to 3 years (1·38 per year; 1·23–1·56). For children aged 3–7 years, the mortality risk decreased slightly (p=0·0104 for the change in slope).

Interpretation

This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.

Funding

Queen Elizabeth Diamond Jubilee Trust.

Treatment of Aggressive Retinal Astrocytic Hamartoma with Oral mTOR Inhibition

OBJECTIVE OR PURPOSE

To describe the clinical course and outcomes of aggressive retinal astrocytic hamartoma (RAH) treated with oral mTOR inhibitors (mTORi).

DESIGN

Retrospective clinical case series.

SUBJECTS, PARTICIPANTS, AND/OR CONTROLS

Five patients with genetically confirmed TSC and visually significant RAH due to tumor growth or exudation.

METHODS, INTERVENTION, OR TESTING

Review of the electronic medical record in this retrospective clinical case series was performed to determine baseline and follow-up ophthalmologic examination characteristics along with ancillary imaging findings, in patients receiving off-label treatment with either oral sirolimus or everolimus for symptomatic RAH.

MAIN OUTCOME MEASURES

Visual acuity, change in tumor size, degree of exudation, and adverse effects of mTORi were evaluated.

RESULTS

The five patients in this series ranged in age from 8 months to 54 years. Four were treated with sirolimus, and one received everolimus. In all cases, tumor height was stable or decreased following treatment (median follow-up: 39 months, range 11-73 months). Exudation improved following treatment in all cases. In the 8-month-old infant, frequent upper respiratory tract infections prompted cessation of treatment. In one patient, the mTORi was temporarily held due to elevated liver enzymes. No other significant adverse effects were noted.

CONCLUSIONS

Sirolimus and everolimus should be considered in the management of vision-threatening RAH, particularly in the setting of exudative and rapidly growing tumors. Four out of five patients in this series tolerated oral mTORi and continued on therapy. There were no serious complications.

Relevance of circulating hybrid cells as a non-invasive biomarker for myriad solid tumors

Metastatic progression defines the final stages of tumor evolution and underlies the majority of cancer-related deaths. The heterogeneity in disseminated tumor cell populations capable of seeding and growing in distant organ sites contributes to the development of treatment resistant disease. We recently reported the identification of a novel tumor-derived cell population, circulating hybrid cells (CHCs), harboring attributes from both macrophages and neoplastic cells, including functional characteristics important to metastatic spread. These disseminated hybrids outnumber conventionally defined circulating tumor cells (CTCs) in cancer patients. It is unknown if CHCs represent a generalized cancer mechanism for cell dissemination, or if this population is relevant to the metastatic cascade. Herein, we detect CHCs in the peripheral blood of patients with cancer in myriad disease sites encompassing epithelial and non-epithelial malignancies. Further, we demonstrate that in vivo-derived hybrid cells harbor tumor-initiating capacity in murine cancer models and that CHCs from human breast cancer patients express stem cell antigens, features consistent with the potential to seed and grow at metastatic sites. Finally, we reveal heterogeneity of CHC phenotypes reflect key tumor features, including oncogenic mutations and functional protein expression. Importantly, this novel population of disseminated neoplastic cells opens a new area in cancer biology and renewed opportunity for battling metastatic disease.

Risk Factors and Disease Course for Blood-Brain Barrier Disruption-Associated Maculopathy

Importance

Blood-brain barrier disruption (BBBD) is a systemic therapy for malignant central nervous system (CNS) tumors that has been linked to poorly understood pigmentary maculopathy.

Objectives

To examine the rate of and risk factors for the development of BBBD-associated maculopathy and to assess whether there can be visually significant progression after completion of systemic therapy.

Design, Setting, and Participants

In this retrospective case series, data from February 1, 2006, through December 31, 2019, were collected from patients treated with osmotic BBBD at a single tertiary referral center who had subsequent ophthalmic evaluation.

Exposures

Treatment with BBBD therapy for any malignant CNS tumor.

Main Outcomes and Measures

Rate and potential risk factors for developing BBBD-associated maculopathy and changes in visual acuity and retinal imaging characteristics after completion of BBBD therapy.

Results

Of 283 patients treated with BBBD and chemotherapy for a CNS malignant neoplasm, 68 (mean [SD] age, 46.0 [17.9] years; 25 [38.5%] female) had an ophthalmic examination after starting systemic therapy. After excluding 3 patients because of bilateral media opacities, pigmentary maculopathy was present in 32 of 65 patients (49.2%) treated with BBBD. The number of BBBD treatment sessions, but not age, CNS malignant cancer type, or systemic chemotherapy agent, was associated with maculopathy development (odds ratio, 1.30; 95% CI, 1.12-1.50; P = .001). After completion of BBBD therapy, progressive enlargement of geographic atrophy occurred in 5 eyes of 3 patients, and choroidal neovascularization developed in 1 eye.

Conclusions and Relevance

In this case series, an association was found between BBBD-related maculopathy and the number of BBBD treatment sessions, suggesting a dose-dependent effect. In some cases, maculopathy progression, including enlargement of geographic atrophy, occurred years after completion of systemic therapy. These findings may have important implications for patient education and ophthalmic monitoring.

Maculopathy Associated With Osmotic Blood- Brain Barrier Disruption and Chemotherapy in Patients With Primary CNS Lymphoma

BACKGROUND AND OBJECTIVE

To describe the incidence, characteristics, and risk factors of a pigmentary maculopathy in patients with primary central nervous system (CNS) lymphoma treated with blood-brain barrier disruption (BBBD) therapy.

PATIENTS AND METHODS

This retrospective chart review included patients with biopsy-proven primary CNS lymphoma treated with or without BBBD therapy who underwent an ophthalmic examination after starting systemic treatment. Clinical data and all available retinal imaging were analyzed.

RESULTS

Fifty-eight patients met inclusion criteria. Twenty-one of 36 patients treated with BBBD therapy had a bilateral pigmentary maculopathy. None of the 22 patients treated with conventional chemotherapy had similar changes. Additional findings in patients treated with BBBD included geographic retinal pigment epithelium atrophy, subretinal fluid, and in one case, choroidal neovascularization. Some cases of maculopathy resulted in reduced visual acuity. The presence of a pigmentary maculopathy was associated with a higher number of BBBD treatment sessions (20.1 vs 13.3, P = .016), but not vitreoretinal lymphoma involvement or intravitreal methotrexate injections.

CONCLUSION

In this cohort, 58.3% of patients with primary CNS lymphoma treated with BBBD and chemotherapy were found to have a bilateral pigmentary maculopathy. This maculopathy can result in reduced visual acuity and is associated with the number of BBBD treatment sessions. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:S5-S12.].

Clinical challenges in interpreting multiple pathogenic mutations in single patients

Background

In the past two decades, genetic testing for cancer risk assessment has entered mainstream clinical practice due to the availability of low-cost panels of multiple cancer-associated genes. However, the clinical value of multiple-gene panels for cancer susceptibility is not well established, especially in cases where panel testing identifies more than one pathogenic variant. The risk for specific malignancies as a result of a mutated gene is complex and likely influenced by superimposed modifier variants and/or environmental effects. Recent data suggests that the combination of multiple pathogenic variants may be fewer than reported by chance, suggesting that some mutation combinations may be detrimental. Management of patients with “incidentally” discovered mutations can be particularly challenging, especially when established guidelines call for radical procedures (e.g. total gastrectomy in CDH1) in patients and families without a classic clinical history concerning for that cancer predisposition syndrome.

Case presentation

We present two cases, one of an individual and one of a family, with multiple pathogenic mutations detected by multi-gene panel testing to highlight challenges practitioners face in counseling patients about pathogenic variants and determining preventive and therapeutic interventions.

Conclusions

Ongoing investigation is needed to improve our understanding of inherited susceptibility to disease in general and cancer predisposition syndromes, as this information has the potential to lead to the development of more precise and patient-specific counseling and surveillance strategies. The real-world adoption of new or improved technologies into clinical practice frequently requires medical decision-making in the absence of established understanding of gene-gene interactions. In the meantime, practitioners must be prepared to apply a rationale based on currently available knowledge to clinical decision-making. Current practice is evolving to rely heavily on clinical concordance with personal and family history in making specific therapeutic decisions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13053-021-00172-3.

Global Retinoblastoma Presentation and Analysis by National Income Level

Importance

Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale.

Objectives

To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis.

Design, Setting, and Participants

A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017.

Main Outcomes and Measures

Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis.

Results

The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]).

Conclusions and Relevance

This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs.

Practice Patterns for the Treatment of Uveal Melanoma with Iodine-125 Plaque Brachytherapy: Ocular Oncology Study Consortium Report 5

Background

Treatment planning for I-125 plaque therapy for uveal melanoma has advanced significantly since the Collaborative Ocular Melanoma Study trial, with more widely available image-guided planning and improved dosimetry.

Objective

We evaluated real-world practice patterns for I-125 plaque brachytherapy in the United States by studying practice patterns at centers that comprise the Ocular Oncology Study Consortium (OOSC).

Methods

The OOSC database and responses to a treatment practice survey were evaluated. The database contains treatment information from 9 institutions. Patients included in the database were treated between 2010 and 2014. The survey was conducted in 2018 and current treatment planning methods and prescriptions were queried.

Results

Examination of the OOSC database revealed that average doses to critical structures were highly consistent, with the exception of one institution. Survey responses indicated that most centers followed published guidelines regarding dose and prescription point. Dose rate ranged from 51 to 118 cGy/h. As of 2018, most institutions use pre-loaded plaques and fundus photographs and/or computed tomography or magnetic resonance imaging in planning.

Conclusions

While there were differences in dosimetric practices, overall agreement in plaque brachytherapy practices was high among OOSC institutions. Clinical margins and planning systems were similar among institutions, while prescription dose, dose rates, and dosimetry varied.

Longitudinal Detection of Radiation-Induced Peripapillary and Macular Retinal Capillary Ischemia Using OCT Angiography

PURPOSE

To study longitudinal changes in retinal capillary circulation in eyes treated with iodine 125 (I¹²⁵) plaque brachytherapy for uveal melanoma using OCT angiography (OCTA).

DESIGN

Longitudinal prospective study of 21 patients undergoing treatment for uveal melanoma with I¹²⁵ plaque brachytherapy. Eyes with melanoma were imaged with OCTA before treatment and at 12-month intervals until 2 years after brachytherapy.

PARTICIPANTS

After institutional review board approval, participants were enrolled prospectively from an academic ocular oncology clinic.

METHODS

Peripapillary (4.5 × 4.5-mm) and macular (3 × 3-mm) OCTA scans were acquired with AngioVue (Optovue, Inc, Fremont, CA).

MAIN OUTCOME MEASURES

The peripapillary nerve fiber layer plexus capillary density (NFLP_CD), macular superficial vascular complex vessel density (mSVC_VD), and foveal avascular zone (FAZ) area were calculated.

RESULTS

Before treatment, no significant difference was found in the NFLP_CD, mSVC_VD, or FAZ area between eyes with melanoma and normal fellow eyes. By 24 months, 11 eyes had developed clinical signs of radiation retinopathy, radiation optic neuropathy, or both. In treated eyes, the NFLP_CD (48.4±4.1%) was reduced at 12 months (46.7±5.0%; P = 0.04, Wilcoxon signed-rank test) and 24 months (44.5±6.1%; P < 0.001). Similarly, the mSVC_VD (48.4 2±3.6%) was reduced in treated eyes at 12 months (43.5±5.9%; P = 0.01) and 24 months (37.4±9.1%; P < 0.001). The FAZ area (0.26±0.11 mm²) increased in treated eyes at 12 months (0.35±0.22 mm²; P = 0.009) and 24 months (0.81±1.03 mm²; P = 0.001). When only eyes with clinically evident radiation changes were evaluated, the changes in NFLP_CD, mSVC_VD, and FAZ area were more pronounced. OCT angiography measurements correlated with both radiation dose and visual acuity. The mSVC_VD measured at 12 months was found to predict the development of clinically apparent radiation retinopathy within 1 year.

CONCLUSIONS

OCT angiography demonstrated early emergence of peripapillary and macular capillary vasculature changes after I¹²⁵ plaque brachytherapy. OCT angiography provided a quantitative measurement of retinal capillary changes associated with ischemia that correlated with visual acuity and radiation dose and may predict future development of radiation-induced retinal toxicity.

Corneal Substructure Dosimetry Predicts Corneal Toxicity in Patients With Uveal Melanoma Treated With Proton Beam Therapy

PURPOSE

This study examines the relationship between dose to corneal substructures and incidence of corneal toxicity within 6 months of proton beam therapy (PBT) for uveal melanoma. We aim to develop clinically meaningful dose constraints that can be used to mitigate corneal toxicity.

METHODS AND MATERIALS

Ninety-two patients were treated with PBT between 2015 and 2017 and evaluated for grade 2+ (GR2+) intervention-requiring corneal toxicity in our prospectively maintained database. Most patients were treated with 50 Gy (relative biological effectiveness [RBE]) in 5 fractions, and all had complete six-month follow-up. Analyses included Mann-Whitney, χ², Fisher exact, and receiver operating curve tests to identify risk factors for GR2+ toxicity. Bivariate logistic regression was used to identify independent dose-volume histogram (DVH) predictors of toxicity after adjustment for the most important clinical risk factor.

RESULTS

The 6-month PBT GR2+ corneal toxicity rate was 10.9%, with half of patients experiencing grade 2 toxicity and half experiencing grade 3 toxicity, with no grade 4 events. Patients with anterior chamber tumors had a higher risk (58.3%) for toxicity than those with posterior tumors (0%) or posterior tumors extending past the equator (25%, P < .0001). On univariate analysis, larger size according to Collaborative Ocular Melanoma Studies was associated with increased toxicity rate (P < .004). DVH analysis revealed that cutoffs of 58% for V25, 32% for V45, 51.8 Gy (RBE) for maximum dose, and 32 Gy (RBE) for mean dose to the cornea separated patients into groups experiencing and not experiencing toxicity with 90% sensitivity and ≥96% specificity. Bivariate logistic regression indicated that corneal V25, V45, and mean dose independently predicted for toxicity after adjusting for tumor location.

CONCLUSIONS

Patients receiving PBT for anterior uveal melanomas experience a high rate of GR2+ corneal toxicity because of increased corneal dose. Anterior location and corneal DVH parameters independently predict toxicity risk. We propose dosimetric constraints to facilitate treatment planning and toxicity mitigation.

Metastases and death rates after primary enucleation of unilateral retinoblastoma in the USA 2007-2017

BACKGROUND/AIMS

Enucleation for retinoblastoma is performed less often in the past decade due to increasingly widespread alternative therapies, but enucleation remains an important option. There is a paucity of reports on the current incidence of metastases and metastatic deaths in unilateral retinoblastoma from US centres.

METHODS

Retrospective chart review at five tertiary retinoblastoma centres in the USA for unilateral retinoblastoma patients treated with primary enucleation, 2007-2017, with >1 year of follow-up or treatment failure.

RESULTS

Among 228 patients (228 eyes), there were nine metastases (3.9%) and four deaths (1.7%). The Kaplan-Meier estimate at 5 years for metastasis-free survival was 96% (95% CI, 94% to 99 %), and for overall survival was 98% (95% CI 96% to 100%). All metastases were evident within 12 months. Histopathology revealed higher risk pathology (postlaminar optic nerve and/or massive choroidal invasion) in 62 of 228 eyes (27%). Of these higher risk eyes, 39 received adjuvant chemotherapy. There were four subsequent metastases in this higher risk pathology with adjuvant chemotherapy group, with three deaths. Of the nine overall with metastases, seven (78%) showed higher risk pathology. All metastatic patients were classified as Reese-Ellsworth V and International Classification of Retinoblastoma Groups D or E. Initial metastases presented as orbital invasion in seven of nine cases.

CONCLUSIONS

Primary enucleation for unilateral retinoblastoma results in a low rate of metastatic death, but is still associated with a 3.9% chance of metastases within a year of enucleation. Most but not all patients who developed metastases had higher risk histopathological findings.

Vision Loss from Choroidal and Pituitary Metastases Secondary to Renal Cell Carcinoma: A Case Report

A 62-year-old male with a history of metastatic clear cell renal cell carcinoma (ccRCC) presented with decreased vision to 20/50 in the left eye. Fundus examination revealed an elevated, amelanotic mass lesion in the superotemporal macula, without involvement of the central macula by subretinal fluid or tumour. Given incongruity between the fundus findings and the degree of visual impairment, visual field testing was obtained, revealing a bitemporal hemianopia. Magnetic resonance imaging demonstrated optic chiasm compression by a pituitary mass, which had previously been overlooked on computed tomography imaging. Biopsy confirmed metastatic ccRCC to the pituitary, which presented simultaneously with the presumed choroidal metastasis.

Trends in Radiation Practices for Female Ocular Oncologists in North America: A Collaborative Study of the International Society of Ocular Oncology

Background

The aim of this study was to determine the known radiation exposure, attitudes, and consequent risk modifications among female ocular oncologists in North America who routinely administer radioactive plaque brachytherapy treatment and are members of the International Society of Ocular Oncology.

Methods

Nineteen female ocular oncologists completed an anonymous 17-question radiation exposure survey.

Results

Eleven of the participants chose to routinely wear lead protection during surgery; 8 did not. Fifteen of 19 participants reported using an unloaded "nonactive" template to prepare for plaque implantation. During pregnancy, 11 of 13 participants continued to perform plaque brachytherapy. Eight of these 11 undertook measures to decrease radiation exposure self-reported as lead wear and other. The average reported anxiety regarding fertility was 2.1 (SD, 2.2) on a scale from 1 to 10.

Conclusion

This study corroborates prior literature that surgeons' exposure to radiation during plaque brachytherapy is minimal. Nonetheless, there remains some anxiety regarding exposure risk to women, due to potential effects on fertility and fetal health. We found variability in exposure monitoring, required training, and precautions during pregnancy amongst this group of surgeons. Improved education and clearer pregnancy guidelines may equip female ocular oncologists with optimal knowledge regarding risk of radiation exposure.

Retinoblastoma and Neuroblastoma Predisposition and Surveillance

Retinoblastoma (RB) is the most common intraocular malignancy in childhood. Approximately 40% of retinoblastomas are hereditary and due to germline mutations in the RB1 gene. Children with hereditary RB are also at risk for developing a midline intracranial tumor, most commonly pineoblastoma. We recommend intensive ocular screening for patients with germline RB1 mutations for retinoblastoma as well as neuroimaging for pineoblastoma surveillance. There is an approximately 20% risk of developing second primary cancers among individuals with hereditary RB, higher among those who received radiotherapy for their primary RB tumors. However, there is not yet a clear consensus on what, if any, screening protocol would be most appropriate and effective. Neuroblastoma (NB), an embryonal tumor of the sympathetic nervous system, accounts for 15% of pediatric cancer deaths. Prior studies suggest that about 2% of patients with NB have an underlying genetic predisposition that may have contributed to the development of NB. Germline mutations in ALK and PHOX2B account for most familial NB cases. However, other cancer predisposition syndromes, such as Li-Fraumeni syndrome, RASopathies, and others, may be associated with an increased risk for NB. No established protocols for NB surveillance currently exist. Here, we describe consensus recommendations on hereditary RB and NB from the AACR Childhood Cancer Predisposition Workshop. Clin Cancer Res; 23(13); e98-e106. ©2017 AACRSee all articles in the online-only CCR Pediatric Oncology Series.

Quantitative OCT Angiography Evaluation of Peripapillary Retinal Circulation after Plaque Brachytherapy

OBJECTIVE

To study peripapillary retinal capillary circulation in eyes treated with I-125 plaque brachytherapy for uveal melanoma using optical coherence tomography angiography (OCTA).

DESIGN

Cross-sectional study of 10 subjects imaged with OCTA prior to uveal melanoma treatment and 15 subjects imaged after development of radiation retinopathy and/or optic neuropathy.

PARTICIPANTS

Following IRB approval, subjects were enrolled from an academic ocular oncology clinical practice. All subjects had uveal melanoma in one eye and treatment with I-125 plaque brachytherapy was planned or had previously taken place. Patients with low vision at baseline and uncontrolled hypertension were excluded. In the post-treatment group, seven subjects were male and eight were female; age range 38 to 81 years. Visual acuities in the irradiated eyes ranged from 20/20 to counting fingers. Visual acuities in the untreated fellow eyes were 20/25 or better.

METHODS

Peripapillary retinal capillary circulation was measured by OCTA (Optovue, Inc). 4.5×4.5 mm optic disc scans were obtained. 10 subjects were imaged prior to brachytherapy treatment and 15 subjects were imaged after development of clinically apparent radiation retinopathy and/or radiation optic neuropathy post-brachytherapy.

MAIN OUTCOME MEASURES

The relationship of the peripapillary retinal capillary density (PPCD) as measured by OCTA to the calculated dose to the optic nerve (D50, the dose to 50% of the disc) and the LogMAR vision was evaluated.

RESULTS

No significant difference was seen in the PPCD as measured by OCTA when comparing the eye with melanoma to the fellow eye prior to brachytherapy; however the PPCD was significantly lower in treated eyes (52.9% +/- 22.4%) than in fellow eyes that did not receive radiation (73.3% +/- 13.7%, p = 0.004). There was an inverse linear correlation between D50 and the PPCD (Pearson's; r= -0.528, P=0.043) and between visual acuity and the PPCD (Pearson's; r= -0.564, P=0.028).

CONCLUSIONS

Among patients with clinically apparent radiation retinopathy and/or radiation optic neuropathy, PPCD was lower in the treated eye and correlated with the radiation dose to the optic nerve and the visual acuity. OCTA provides a measure of capillary changes following radiation, and may serve as a quantitative endpoint to address visual prognosis.

Optical coherence tomography angiography of a pigmented Fuchs' adenoma (age-related hyperplasia of the nonpigmented ciliary body epithelium) masquerading as a ciliary body melanoma

Purpose

To report a case of age-related hypertrophy of the nonpigmented ciliary epithelium (ARH-NPCE) clinically resembling a ciliary body melanoma and report the optical coherence tomography angiography (OCTA) findings associated with this lesion.

Observations

A 51-year-old male was referred for evaluation of a deeply pigmented ciliary body mass with extension through the iris root. Iridocyclectomy was performed due to concern for ciliary body melanoma. Histopathologic analysis was instead consistent with ARH-NPCE, also known as Fuchs' adenoma. Prior to surgery, OCTA images revealed abnormal vasculature in the area of the lesion. Vessels in the peripheral iris approaching the lesion appeared more tortuous and were non-radial as compared with normal iris vessels. The ciliary body mass itself could not be penetrated using an OCTA system operating at 1050 nm.

Conclusions and importance

ARH-NPCE may clinically resemble a pigmented ciliary body melanoma. This is the second case describing this clinical scenario, which may be more common than previously thought. Non-invasive imaging with OCTA revealed an abnormal peripheral iris vasculature pattern in the area of the iridociliary mass characterized by disorganized, tortuous, and non-radial vessels. Despite advances in longer wavelength OCTA systems, poor penetration of the ciliary body lesion precluded imaging of the intratumoral vessels in this location.

Uveal Melanoma with Histopathologic Intratumoral Heterogeneity Associated with Gene Expression Profile Discordance

PURPOSE

To report a case of intratumoral gene expression profile discordance in a malignant uveal melanoma, associated with intratumoral heterogeneity based upon histopathologic features.

METHODS

The clinical history, fundus findings, imaging and histopathologic features, and DecisionDx-UM gene expression profile results (Castle Biosciences, Inc., Phoenix, AZ, USA) of the tumor were reviewed.

RESULTS

A trans-retinal fine-needle aspiration biopsy was performed for a thin, pigmented choroidal tumor in a 33-year-old man. Cells obtained from this biopsy were tested using the DecisionDx-UM gene expression profile test and the tumor was classified as class 1A. Cytology confirmed melanoma. The patient subsequently elected to undergo enucleation. On microscopic examination of the globe, the tumor was composed primarily of spindle B cells, but had a focal area composed of epithelioid cells. This portion of the tumor was subsequently tested and demonstrated a class 1B gene expression profile.

CONCLUSION

Intratumoral discordance in gene expression profile results has been described in uveal melanomas. Here we demonstrate that this discordance may be associated in some cases with intratumoral heterogeneity based upon histopathologic features.

Optical Coherence Tomography Angiography Characteristics of Iris Melanocytic Tumors

PURPOSE

To evaluate tumor vasculature with optical coherence tomography angiography (OCTA) in malignant iris melanomas and benign iris lesions.

DESIGN

Cross-sectional observational clinical study.

PARTICIPANTS

Patients with iris lesions and healthy volunteers.

METHODS

Eyes were imaged using OCTA systems operating at 1050- and 840-nm wavelengths. Three-dimensional OCTA scans were acquired. Iris melanoma patients treated with radiation therapy were imaged again after I-125 plaque brachytherapy at 6 and 18 months.

MAIN OUTCOME MEASURES

OCT and OCTA images, qualitative evaluation of iris and tumor vasculature, and quantitative vessel density.

RESULTS

One eye each of 8 normal volunteers and 9 patients with iris melanomas or benign iris lesions, including freckles, nevi, and an iris pigment epithelial (IPE) cyst, were imaged. The normal iris has radially oriented vessels within the stroma on OCTA. Penetration of flow signal in normal iris depended on iris color, with best penetration seen in light to moderately pigmented irides. Iris melanomas demonstrated tortuous and disorganized intratumoral vasculature. In 2 eyes with nevi there was no increased vascularity; in another, fine vascular loops were noted near an area of ectropion uveae. Iris freckles and the IPE cyst did not have intrinsic vascularity. The vessel density was significantly higher within iris melanomas (34.5%±9.8%, P < 0.05) than in benign iris nevi (8.0%±1.4%) or normal irides (8.0%±1.2%). Tumor regression after radiation therapy for melanomas was associated with decreased vessel density. OCTA at 1050 nm provided better visualization of tumor vasculature and penetration through thicker tumors than at 840 nm. But in very thick tumors and highly pigmented lesions even 1050-nm OCTA could not visualize their full thickness. Interpretable OCTA images were obtained in 82% of participants in whom imaging was attempted.

CONCLUSIONS

This is the first demonstration of OCTA in iris tumors. OCTA may provide a dye-free, no-injection, cost-effective method for monitoring a variety of tumors, including iris melanocytic lesions, for growth and vascularity. This could be helpful in evaluating tumors for malignant transformation and response to treatment. Penetration of the OCT beam remains a limitation for highly pigmented tumors, as does the inability to image the entire iris in a single field.

Bilateral Idiopathic Solitary Granuloma of the Uveal Tract: Diagnosis and Treatment

We present a case of sequential bilateral idiopathic solitary granuloma of the uveal tract in a 51 year-old woman, who underwent enucleation in one eye due to complications of this condition, but was then successfully treated in the contralateral eye with anti-tumor necrosis-alpha therapy followed shortly by intraocular steroids and a steroid-releasing implant. Her visual acuity at its worst was 20/200 due to vitreous haze and cystoid macular edema, but then stabilized after successful treatment with a final visual acuity of 20/25 in her only seeing eye at 1 year follow-up. This represents the first known biopsy-proven case of bilateral idiopathic solitary granuloma, which additionally, has responded favorably to treatment.

Accuracy and reliability of telemedicine for diagnosis of cytomegalovirus retinitis

PURPOSE

To determine the feasibility of remote diagnostic screening for cytomegalovirus (CMV) retinitis among HIV patients in northern Thailand.

DESIGN

Prospective, observational cross-sectional study.

METHODS

One hundred eighty-two eyes from 94 consecutive patients with HIV seen in 2008 and 2009 at a tertiary university-based medical center were photographed using a digital retinal camera. Individual and composite images were uploaded to a secure web site. Three expert graders accessed the electronic images and graded each image for signs of CMV retinitis. Results of remote expert grading were compared with on-site patient examination by local expert ophthalmologists.

RESULTS

On-site ophthalmologists diagnosed CMV retinitis in 89 (48.9%) of 182 eyes. Trained ophthalmic photographers obtained digital retinal images for all 182 eyes. As compared with the on-site examinations, the sensitivity for detecting CMV retinitis by remote readers using composite retinal images ranged from 89% to 91%. The specificity for detecting CMV retinitis by remote readers ranged from 85% to 88%. Intrarater reliability was high, with each grader achieving a κ value of 0.93. Interrater reliability among the 3 graders also was high, with a κ value of 0.86.

CONCLUSIONS

Remote diagnostic screening for CMV retinitis among HIV-positive patients may prove to be a valuable tool in countries where the burden of HIV exceeds the capacity of the local eye care providers to screen for ocular opportunistic infections.

Antibiotic selection pressure and macrolide resistance in nasopharyngeal Streptococcus pneumoniae: a cluster-randomized clinical trial

BACKGROUND

It is widely thought that widespread antibiotic use selects for community antibiotic resistance, though this has been difficult to prove in the setting of a community-randomized clinical trial. In this study, we used a randomized clinical trial design to assess whether macrolide resistance was higher in communities treated with mass azithromycin for trachoma, compared to untreated control communities.

METHODS AND FINDINGS

In a cluster-randomized trial for trachoma control in Ethiopia, 12 communities were randomized to receive mass azithromycin treatment of children aged 1-10 years at months 0, 3, 6, and 9. Twelve control communities were randomized to receive no antibiotic treatments until the conclusion of the study. Nasopharyngeal swabs were collected from randomly selected children in the treated group at baseline and month 12, and in the control group at month 12. Antibiotic susceptibility testing was performed on Streptococcus pneumoniae isolated from the swabs using Etest strips. In the treated group, the mean prevalence of azithromycin resistance among all monitored children increased from 3.6% (95% confidence interval [CI] 0.8%-8.9%) at baseline, to 46.9% (37.5%-57.5%) at month 12 (p = 0.003). In control communities, azithromycin resistance was 9.2% (95% CI 6.7%-13.3%) at month 12, significantly lower than the treated group (p < 0.0001). Penicillin resistance was identified in 0.8% (95% CI 0%-4.2%) of isolates in the control group at 1 year, and in no isolates in the children-treated group at baseline or 1 year.

CONCLUSIONS

This cluster-randomized clinical trial demonstrated that compared to untreated control communities, nasopharyngeal pneumococcal resistance to macrolides was significantly higher in communities randomized to intensive azithromycin treatment. Mass azithromycin distributions were given more frequently than currently recommended by the World Health Organization's trachoma program. Azithromycin use in this setting did not select for resistance to penicillins, which remain the drug of choice for pneumococcal infections.

TRIAL REGISTRATION

www.ClinicalTrials.gov NCT00322972. Please see later in the article for the Editors' Summary.

Telemedicine screening for retinopathy of prematurity in developing countries using digital retinal images: a feasibility project

PURPOSE

To determine the feasibility in a middle-level human development country of onsite training, image collection, Internet transfer, and remote grading of digital retinal images from babies screened for retinopathy of prematurity (ROP).

METHODS

Two experienced nurses in a neonatal nursery in Lima, Peru, were trained to take posterior pole (30 degrees ) digital retinal images. Nurses obtained posterior pole retinal images from babies undergoing routine ROP screening and selected images for uploading via Internet for remote evaluation by five masked ROP experts. Results of gradings were compared with same-day clinical diagnostic examinations by an experienced ophthalmologist. Success rates for image acquisition and transfer for grading by expert readers were calculated.

RESULTS

Serial image sets from 26 of the 28 babies enrolled in this study were obtained; two babies were too unstable for imaging. Fifty-six of 58 (96.6%) imaging sessions were successful in obtaining retinal images. Three hundred thirty of 336 (98.2%) images obtained were successfully uploaded to an interactive database. Remote graders judged 93.6% to 97.3% of image sets suitable for ROP grading. Preliminary results indicate sensitivities for detection of serious ROP from 45.5% to 95.2% among individual readers, with specificities of 61.7% to 96.2% when images were gradable.

CONCLUSIONS

A telemedicine approach for ROP screening using digital retinal images obtained by nonophthalmologists is feasible in rapidly developing countries that lack ROP-trained ophthalmologists. If remote grading of digital images is validated as an effective method for identifying referral-warranted ROP (RW-ROP), images obtained by nonphysicians may provide a means of identifying babies who require a diagnostic examination by an ophthalmologist.

Rapid B cell receptor-induced unfolded protein response in nonsecretory B cells correlates with pro- versus antiapoptotic cell fate

The adaptive unfolded protein response (UPR) is essential for the development of antibody-secreting plasma cells. B cells induced by lipopolysaccharide (LPS) to differentiate into plasma cells exhibit a nonclassical UPR reported to anticipate endoplasmic reticulum stress prior to immunoglobulin production. Here we demonstrate that activation of a physiologic UPR is not limited to cells undergoing secretory cell differentiation. We identify B cell receptor (BCR) signaling as an unexpected physiologic UPR trigger and demonstrate that in mature B cells, BCR stimulation induces a short lived UPR similar to the LPS-triggered nonclassical UPR. However, unlike LPS, BCR stimulation does not induce plasma cell differentiation. Furthermore, the BCR-induced UPR is not limited to cells in which BCR induces activation, since a UPR is also induced in transitional immature B cells that respond to BCR stimulation with a rapid apoptotic fate. This response involves sustained up-regulation of Chop mRNA indicative of a terminal UPR. Whereas sustained Chop expression correlates with the ultimate fate of the BCR-triggered B cell and not its developmental stage, Chop-/- B cells undergo apoptosis, indicating that CHOP is not required for this process. These studies establish a system whereby a terminal or adaptive UPR can be alternatively triggered by physiologic stimuli.

Human cytomegalovirus infection activates and regulates the unfolded protein response

Viral infection causes stress to the endoplasmic reticulum. The response to endoplasmic reticulum stress, known as the unfolded protein response (UPR), is designed to eliminate misfolded proteins and allow the cell to recover by attenuating translation and upregulating the expression of chaperones, degradation factors, and factors that regulate the cell's metabolic and redox environment. Some consequences of the UPR (e.g., expression of chaperones and regulation of the metabolism and redox environment) may be advantageous to the viral infection; however, translational attenuation would not. Thus, viruses may induce mechanisms which modulate the UPR, maintaining beneficial aspects and suppressing deleterious aspects. We demonstrate that human cytomegalovirus (HCMV) infection induces the UPR but specifically regulates the three branches of UPR signaling, PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6), and inositol-requiring enzyme 1 (IRE-1), to favor viral replication. HCMV infection activated the eIF2alpha kinase PERK; however, the amount of phosphorylated eIF2alpha was limited and translation attenuation did not occur. Interestingly, translation of select mRNAs, which is dependent on eIF2alpha phosphorylation, did occur, including the transcription factor ATF4, which activates genes which may benefit the infection. The endoplasmic reticulum stress-induced activation of the transcription factor ATF6 was suppressed in HCMV-infected cells; however, specific chaperone genes, normally activated by ATF6, were activated by a virus-induced, ATF6-independent mechanism. Lastly, HCMV infection activated the IRE-1 pathway, as indicated by splicing of Xbp-1 mRNA. However, transcriptional activation of the XBP-1 target gene EDEM (ER degradation-enhancing alpha-mannosidase-like protein, a protein degradation factor) was inhibited. These results suggest that, although HCMV infection induces the unfolded protein response, it modifies the outcome to benefit viral replication.