High-risk retinoblastoma based on international classification of retinoblastoma: analysis of 519 enucleated eyes

Tumor heterogeneity in retinoblastoma: a literature review

Tumor heterogeneity, characterized by the presence of diverse cell populations within a tumor, is a key feature of the complex nature of cancer. This diversity arises from the emergence of cells with varying genomic, epigenetic, transcriptomic, and phenotypic profiles over the course of the disease. Host factors and the tumor microenvironment play crucial roles in driving both inter-patient and intra-patient heterogeneity. These diverse cell populations can exhibit different behaviors, such as varying rates of proliferation, responses to treatment, and potential for metastasis. Both inter-patient heterogeneity and intra-patient heterogeneity pose significant challenges to cancer therapeutics and management. In retinoblastoma, while heterogeneity at the clinical presentation level has been recognized for some time, recent attention has shifted towards understanding the underlying cellular heterogeneity. This review primarily focuses on retinoblastoma heterogeneity and its implications for therapeutic strategies and disease management, emphasizing the need for further research and exploration in this complex and challenging area.

High-Risk Retinoblastoma Based on International Classification Systems: Analysis of 1362 Eyes

PURPOSE

To determine the predictive value of International Intraocular Retinoblastoma Classification schemes and the American Joint Committee on Cancer (AJCC) classification for histopathological high-risk features (HRFs).

DESIGN

Multicentric international collaborative retrospective case series.

SUBJECTS

One thousand three hundred and sixty-two patients with retinoblastoma from 16 centers and 11 countries.

INTERVENTION

Primary enucleation; adjuvant therapy in patients with HRF.

MAIN OUTCOME MEASURES

High-risk retinoblastoma defined as 1 or more HRF (anterior segment involvement, massive choroidal invasion, minor choroidal infiltration with prelaminar optic nerve invasion, retrolaminar or resected optic nerve cut end involvement, scleral or microscopic extrascleral infiltration); metastasis-free survival (MFS).

RESULTS

Of the 1362 patients, 751 (55.1%) had HRF. According to the International Classification of Retinoblastoma (ICRB) (Philadelphia vs. Los Angeles [LA]) versus Children's Oncology Group (COG) classification schemes, the positive predictive value (PPV) of group D eyes for HRF was 42.0% versus 35.1% versus 43.2%, respectively, and that for group E eyes was 58.5% versus 59.0% versus 59.5%, respectively. Comparing group D versus group E eyes, there was higher mean number of HRF (standard deviation, range) among group E eyes using the ICRB Philadelphia (0.7 [0.9, 0.0-6.0] vs. 1.3 [1.7, 0.0-9.0], P < 0.001), ICRB LA (0.6 [0.8, 0.0-6.0] vs. 1.3 [1.7, 0.0-9.0], P < 0.001) and COG (0.8 [1.2, 0.0-7.0] vs. 1.3 [1.6, 0.0-8.0], P < 0.001) classifications. The PPV for HRF was above 55% for AJCC clinical tumor (cT) group cT3a with increments through cT3e to 72.3%. An agreement between ICRB Philadelphia versus ICRB LA, ICRB LA versus COG, and ICRB Philadelphia versus COG was 0.9, 0.8, and 0.8, respectively (P < 0.001). Metastasis-free survival rates and overall survival rates were also comparable between all intraocular retinoblastoma classification schemes but better stratified within the AJCC scheme.

CONCLUSIONS

All intraocular retinoblastoma classification schemes predict HRF and MFS equally. Group E includes a wide spectrum equivalent to the AJCC group cT3. Uniform grouping with subcategorization of group E might improve risk stratification. We propose that everyone across the retinoblastoma world henceforth adopts the AJCC classification for all reporting and publishing.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any materials discussed in this article.

Impact of Race on the Outcomes of Retinoblastoma Treated With Primary Enucleation: A Global Study of 1426 Patients

BACKGROUND

To evaluate the clinical presentation, pathological features and outcomes of retinoblastoma based on the race of origin in a global cohort of patients.

METHODS

Retrospective collaborative study of 1426 patients who underwent primary enucleation for retinoblastoma.

RESULTS

Patients were grouped into Caucasians (n = 231, 16%), Asians (n = 841, 59%), Hispanics (n = 226, 16%), Arabs (n = 96, 7%) and Others (Africans, African Americans, Indigenous Australians; n = 32, 2%) cohorts. On histopathology, massive choroidal invasion was higher in Asians (30%) and Hispanics (26%) than Caucasians (15%, p < 0.001). Post-laminar optic nerve invasion was higher in Asians (28%), Hispanics (20%) and Others (9%) than Caucasians (11%, p < 0.001). At a mean follow-up of 41 months (median, 35 months; range, < 1-149 months), tumour recurrence and metastasis-related death was higher in Hispanics (9% and 12%, respectively), Asians (4% and 13%, respectively) and Others (6% and 6%, respectively). Multivariate Cox proportional hazards analysis of outcomes based on race with 8th edition AJCC pT stage and adjuvant therapy as covariates revealed 6.8 times greater risk for orbital tumour recurrence in Hispanics compared to Caucasians (p = 0.010) and 3.2 times risk hazards for metastasis-related death in Hispanics and Asians compared to Caucasians (p = 0.028 and p = 0.038, respectively).

CONCLUSION

The histopathological features in primarily enucleated eyes with retinoblastoma vary with race. Despite adjusting for tumour staging and adjuvant treatment, race remains an independent predictor of outcomes, including orbital tumour recurrence and metastasis-related death. A stringent follow-up and a more aggressive treatment approach is recommended in Asians and Hispanics who manifest high-risk histopathological features.

Management of retinoblastoma: are we there yet?

Since the introduction of intraarterial chemotherapy (IAC) in the last decade, there has been a paradigm shift in the management of retinoblastoma (RB), especially in developed countries. Despite improved globe salvage outcomes with IAC compared with systemic intravenous chemotherapy, IAC has certain limitations, such as poor accessibility and affordability, especially for middle- and low-income countries; the need for expertise; local ocular complications; and possible increased risk of systemic metastasis. This review discusses the important limitations of the current treatment strategy of using IAC, as well as the prospects of new therapeutic targets or routes of drug delivery that may lead to further improvements in the management of RB.

A retrospective study on adjuvant chemotherapy in retinoblastoma: validation of the new recommendation against treatment for pT2a tumors based on the 8th AJCC classification

BACKGROUND

Retinoblastoma (RB) is an intraocular malignant tumor detected in early childhood with variable global impact. Histopathological classification of the tumor in enucleated globes with RB is the key for the decision of adjuvant chemotherapy use. We aim to validate the use of adjuvant chemotherapy in cases with combined pre-laminar/intralaminar optic nerve (ON) invasion and focal choroidal invasion according to the American Joint Committee on Cancer (AJCC) 8th classification.

METHODS

This is a retrospective study conducted at King Abdulaziz University Hospital (KAUH) and King Khalid Eye Specialist Hospital (KKESH) in Riyadh, Saudi Arabia of all RB cases who underwent enucleation over 22 years (2000 to 2021). The histopathological findings were reviewed to identify the enucleated globes classified as pT2a tumors, as an inclusion criterion. Basic demographic and clinical data were collected via chart review Simple descriptive and basic statistical analysis of the data was used where applicable.

RESULTS

Thirty-one patients who had an enucleated globe with RB that fit into the above classification were included. Sixteen were males and 15 were females. The median age was 14 months (IQR = 14 months). Most of the patients (93.5%) had no family history of RB. The commonest presentation was leukocoria in 87.1% followed by squint in 32.3%. Fourteen patients (45.2%) were treated by enucleation alone while 17 patients (54.8%) received adjuvant chemotherapy. Out of these, 7 patients had unilateral RB and the remaining 10 patients had bilateral RB. None of our patients developed recurrence or metastatic disease irrespective of the indication for adjuvant chemotherapy use after a maximum period of follow up reaching 17.84 years and a median of 10.6 years (IQR = 5.92).

CONCLUSIONS

In patients with 8th AJCC histopathological classification of pT2a, chemotherapy following enucleation might not be justified. The outcome in our untreated group of patients did not differ from the treated group with the absence of metastasis after a relatively long period of follow up with a median exceeding 10 years in both groups. Therefore, the risk and benefit of post enucleation adjuvant chemotherapy in the treatment of unilateral RB should be carefully decided and discussed with the primary caregivers taking into consideration the most recent evidence and recommendations in the literature.

Optic nerve thickening on high-spatial-resolution MRI predicts early-stage postlaminar optic nerve invasion in retinoblastoma

OBJECTIVES

To assess the diagnostic accuracy of nerve thickening on MRI to predict early-stage postlaminar optic nerve invasion (PLONI) in retinoblastoma. Furthermore, this study aimed to incorporate measurements into a multiparametric model for radiological determination of PLONI.

METHODS

In this retrospective multicenter case-control study, high-spatial-resolution 3D T2-weighted MR images were used to measure the distal optic nerve. Histopathology was the reference standard for PLONI. Two neuroradiologists independently measured the optic nerve width, height, and surface at 0, 3, and 5 mm from the most distal part of the optic nerve. Subsequently, PLONI was scored on contrast-enhanced T1-weighted and 3D T2-weighted images, blinded for clinical data. Optic nerve measurements with the highest diagnostic accuracy for PLONI were incorporated into a prediction model for radiological determination of PLONI.

RESULTS

One hundred twenty-four retinoblastoma patients (median age, 22 months [range, 0-113], 58 female) were included, resulting in 25 retinoblastoma eyes with histopathologically proven PLONI and 206 without PLONI. ROC analysis of axial optic nerve width measured at 0 mm yielded the best area under the curve of 0.88 (95% confidence interval: 0.79, 0.96; p < 0.001). The optimal width cutoff was ≥ 2.215 mm, with a sensitivity of 84% (95% CI: 64, 95%) and specificity of 83% (95% CI: 75, 89%) for detecting PLONI. Combining width measurements with the suspicion of PLONI on MRI sequences resulted in a prediction model with an improved sensitivity and specificity of respectively up to 88% and 92%.

CONCLUSION

Postlaminar optic nerve thickening can predict early-stage postlaminar optic nerve invasion in retinoblastoma.

CLINICAL RELEVANCE STATEMENT

This study provides an additional tool for clinicians to help determine postlaminar optic nerve invasion, which is a risk factor for developing metastatic disease in retinoblastoma patients.

KEY POINTS

• The diagnostic accuracy of contrast-enhanced MRI for detecting postlaminar optic nerve invasion is limited in retinoblastoma patients. • Optic nerve thickening can predict postlaminar optic nerve invasion. • A prediction model combining MRI features has a high sensitivity and specificity for detecting postlaminar optic nerve invasion.

Clinicodemographic profile, management, and treatment outcomes in advanced retinoblastoma at a tertiary care center in North India

PURPOSE

The study was undertaken to look into the clinicodemographic profile, management, and clinical outcomes of advanced retinoblastoma at a tertiary care center.

METHODS

A prospective cohort study was conducted from Jan 2019 to Dec 2022. Forty-two patients of intraocular advanced retinoblastoma were assessed. The treatment protocol was formulated based on size, extension of tumor, and laterality. Primary outcome measure was response to the treatment in terms of regression of tumor and seeds and no evidence of recurrence after 12 month in enucleated eyes. Secondary outcome measures were complications like implant exposure, metastasis, and death associated with each treatment modality.

RESULTS

The mean age of the study group was 13 months. The most common presentation was leukocoria with diminished vision. Most of the patients had group E retinoblastoma ( n = 40, 95%) as per the International Classification of Retinoblastoma. In 12 patients with group E retinoblastoma, primary enucleation was performed and in six patients, secondary enucleation was done, in which initially, globe salvage treatment was tried. In 30 patients, globe salvage treatment was attempted and we could manage to save 23 eyes. The most common treatment modality was intra-arterial chemotherapy using a triple-drug regimen. One patient developed intracranial spread and died due to systemic metastasis during the follow-up period.

CONCLUSION

The current study showed that globe salvage is possible in advanced retinoblastoma if appropriate therapy is instituted depending upon the extent of the tumor and availability of latest treatment modalities. Intra-arterial chemotherapy using triple drugs can be offered as a first-line therapy in advanced unilateral retinoblastoma as it has been found to be very effective in the present study.

Recent progress in retinoblastoma: Pathogenesis, presentation, diagnosis and management

Retinoblastoma, the primary ocular malignancy in pediatric patients, poses a substantial threat to mortality without prompt and effective management. The prognosis for survival and preservation of visual acuity hinges upon the disease severity at the time of initial diagnosis. Notably, retinoblastoma has played a crucial role in unraveling the genetic foundations of oncogenesis. The process of tumorigenesis commonly begins with the occurrence of biallelic mutation in the RB1 tumor suppressor gene, which is then followed by a cascade of genetic and epigenetic alterations that correspond to the clinical stage and pathological features of the tumor. The RB1 gene, recognized as a tumor suppressor, encodes the retinoblastoma protein, which plays a vital role in governing cellular replication through interactions with E2F transcription factors and chromatin remodeling proteins. The diagnosis and treatment of retinoblastoma necessitate consideration of numerous factors, including disease staging, germline mutation status, family psychosocial factors, and the resources available within the institution. This review has systematically compiled and categorized the latest developments in the diagnosis and treatment of retinoblastoma which enhanced the quality of care for this pediatric malignancy.

A comparison of high risk pathological features between primary and secondary enucleation for retinoblastoma

AIM

To compare the risk and pattern of High-Risk Pathologic Features (HRPF) in retinoblastoma between primary and secondary enucleation.

METHODS

A retrospective analysis of 121 eyes from 118 patients who underwent enucleation at the King Hussein Cancer Center (KHCC) Amman, Jordan, between November 2009 and January 2020. Demographic information, tumor stage, time from diagnosis-to-enucleation, results of pathology, metastasis, and mortality were retrieved.

RESULTS

Patients in the secondary group (49/121 eyes, 40%) were considerably younger at diagnosis (p = 0.0014), had bilateral disease (p = 0.0001), and had less-progressed disease at presentation (p = 0.016) compared to the primary enucleation. Primarily enucleated eyes were more-likely to have massive choroidal invasion (p = 0.0315) and post-laminar optic nerve invasion (p = 0.027), in spite of the finding that the overall prevalence of HRPF was similar between the two groups (35.5 percent vs. 37.5 percent; p = 0.585). The likelihood of anterior chamber invasion, was considerably higher in secondary enucleated eyes (p = 0.013). We evaluated primary and secondary enucleation for each subgroup (D and E) of the International Intraocular Retinoblastoma Classification (IIRC) and found the prevalence of HRPF was comparable (p = 0.58, 1.0, respectively). The difference in time between diagnosis-to-enucleation in secondary enucleation did not predict HRPF (p = 0.50). There was no discernible difference between primary and secondary enucleated eyes in terms of metastasis or survival (p = 0.156 and 0.44, respectively).

CONCLUSION

Systemic chemotherapy has the ability to reduce the extent of tumor expansion that has been pathologically identified. Primary and secondary enucleated eyes are comparable in low metastatic risk only when strict examination and management guidelines are followed.

Association of choroidal invasion with retinoblastoma survival rates

PURPOSE

To assess the impact of varying levels of choroidal invasion on survival from retinoblastoma.

METHODS

A retrospective nationwide analysis of retinoblastoma cases diagnosed between 2004-2016 using the Surveillance, Epidemiology, and End Results database was conducted. Overall survival, cause-specific survival, and all-cause mortality risk were assessed as primary outcomes.

RESULTS

A total of 393 retinoblastoma patients were included, of whom 268 (68.2%) had no choroidal invasion, 91 (23.2%) had focal choroidal invasion, and 34 (8.7%) had massive choroidal invasion on enucleation. A total of 6 deaths occurred throughout an average follow-up period of 72.2 ± 47.1 months: 4 deaths were cancer related. Adjusted Cox regression demonstrated higher all-cause mortality in patients with massive choroidal invasion (HR, 41.29; 95% CI, 4.05-420.49; P = 0.002) relative to those without choroidal invasion; however, those with focal choroidal invasion (HR, 2.69; 95% CI, 0.17-43.09; P = 0.484) demonstrated no difference in all-cause mortality. On further stratification by level of optic nerve invasion (ONI), all cancer-related deaths (4/4) were found to have occurred in patients with massive choroidal invasion and concomitant postlaminar ONI (PLONI). Patients with massive choroidal invasion without PLONI demonstrated 5-year overall and cause-specific survival of 100%, whereas patients with massive choroidal invasion and PLONI demonstrated 5-year overall and cause-specific survival of 80.2%.

CONCLUSIONS

All retinoblastoma-related deaths occurred in patients with both massive choroidal invasion and PLONI. These findings could not establish that massive choroidal invasion is an independent risk factor for poor outcome.

Diffusion‐Weighted MR Imaging of the Optic Nerve Can Improve the Detection of Post‐Laminar Optic Nerve Invasion from Retinoblastoma

BACKGROUND

Post-laminar optic nerve invasion (PLONI) is a high-risk factor for the metastasis of retinoblastoma (RB). Unlike conventional MRI, diffusion-weighted imaging (DWI) reflects histopathological features, and may aid the assessment of PLONI.

PURPOSE

To determine the value of conventional MRI plus DWI in detecting PLONI in RB patients.

STUDY TYPE

Retrospective.

POPULATION

Eighty-three RB patients, including 28 with histopathologically proven PLONI and 55 without PLONI.

FIELD STRENGTH/SEQUENCE

3.0 T, precontrast axial T1-weighted and T2-weighted imaging, DWI, and postcontrast axial, coronal, and oblique-sagittal T1-weighted imaging.

ASSESSMENT

PLONI was assessed using post-enucleation histology and preoperative MRI features (optic nerve signal intensity, enlargement, and enhancement on conventional MRI, and apparent diffusion coefficient [ADC] of the optic nerve on DWI) evaluated by three observers.

STATISTICAL TESTS

MRI features suggesting the presence of PLONI were identified using univariable and multivariable analyses. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to analyze diagnostic performance.

RESULTS

Optic nerve enhancement and low ADC of the optic nerve were significant indicators of PLONI. ROC curve analysis showed that the AUC of the combination of these two features for detecting PLONI was 0.87 (95% confidence interval [CI]: 0.78-0.93). The diagnostic performance of this model was significantly superior to that of optic nerve enhancement alone (0.76, 95% CI: 0.65-0.85) and marginally superior to that of the ADC of the affected optic nerve (0.78, 95% CI: 0.68-0.87, P = 0.051).

DATA CONCLUSION

Conventional MRI combined with DWI can improve the detection of PLONI in RB patients over conventional MRI alone.

EVIDENCE LEVEL

3 Technical Efficacy: Stage 2.

A case of retinoblastoma resulting in phthisis bulbi after proton beam radiation therapy

Purpose

Proton beam radiation therapy (PBRT) is a treatment option for advanced retinoblastoma (RB) resistant to chemotherapy and focal ophthalmic treatment. Here we report a case of RB with phthisis bulbi following PBRT.

Observations

A 16-day-old boy with a family history of RB was referred to our institution. Initial examination revealed an extensive white mass in the right eye and a small tumor near the optic disk of the left eye. The patient was diagnosed with bilateral RB and treated with chemotherapy and focal ophthalmic therapy. The right eye showed shrinkage in the treatment course. The tumor control was not achieved bilaterally, and, therefore, PBRT was performed to preserve the eyes. However, the right eye became significantly phthisical following PBRT and ultimately required enucleation.

Conclusions and importance

PBRT for RB may result in phthisis bulbi. Further investigations of its role and possible complications are warranted.

Correlation of clinical and radiological predictors of retinoblastoma with high-risk histopathological features

INTRODUCTION

Retinoblastoma (RB) tumors having high-risk histopathologic features (HRFs) have an increased risk of metastasis and disease relapse. However, RB has not been studied widely in Pakistan. Therefore, we evaluated the association of clinical, histopathologic, and radiological findings with HRFs in patients with RB who were treated at the Indus Health & Hospital Network in Karachi, Pakistan.

METHODS

We enrolled treatment-naïve patients with RB who received upfront enucleation from September 2017 to February 2021. We evaluated enucleated eyes with the Intraocular Classification of Retinoblastoma system and classified HRFs as invasion of the anterior chamber, including the iris and ciliary body, or massive invasion of the choroid, sclera, or optic nerve (postlaminar and/or up to the transection line).

RESULTS

Of 117 patients with RB treated at our institution during the study period, 54 received upfront enucleation. Unilateral disease was present in 92.6% of cases. The most frequent disease signs and symptoms included the presence of vitreous seeds (30.6%) and leukocoria (100%), respectively. The most frequent HRFs and radiological findings comprised massive choroidal invasion (15.1%) and anterior chamber enhancement (66.7%), respectively. The majority (62.9%) of patients did not exhibit any HRFs. Female sex, pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma had significant predictive ability for HRF occurrence.

CONCLUSION

Pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma are important clinical factors that should be taken into consideration before the management of RB. Early recognition of high-risk histopathological and radiological features is essential for appropriate treatment of RB.

Survival outcomes of unilateral retinoblastoma based on pathological risk stratification-experience at a tertiary care centre in Pakistan

Retinoblastoma (RB) is the most common childhood intraocular malignancy. In high-income countries over the past decade, upfront enucleation for unilateral RB is least favoured due to other alternatives that can help in globe preservation, but in low-middle income countries it is still the preferred option due to lack of resources and expertise. The treatment of RB after enucleation is tailored based on the histopathological risk features, as adjuvant chemotherapy with high-risk features reduces the risk of metastasis. The aim of our study was to analyse the survival outcomes of adjuvant therapy based on histopathological risk stratification in patients who underwent upfront enucleation for unilateral RB with advanced disease. A retrospective study was carried out at Shaukat Khanum Memorial Cancer Hospital and Research Centre, Pakistan. A total 113 patients (aged 3 months till 16 years) diagnosed with unilateral RB who had upfront enucleation from July 2009 till January 2019 were included in this study. The mean age of diagnosis was 37.4 months (±24.5) and male-to-female ratio of 1.3:1. The most common clinical presentation was leukocoria (74.3%). Patients who underwent enucleation had advanced disease; group D present in 62.8% followed by group E (32.7%). Histopathology revealed high-risk features in 29 patients (25.7%) and intermediate risk in 54 patients (47.8%). Disease progression and relapse was seen in patients with high-risk histopathological features. The 4-year over-all survival and EFS observed for this cohort was 74% and 71%. Awareness about the early symptoms among the general population and health care personnel at a nationwide level is needed to facilitate early detection and lessen disease related morbidity and mortality.

MRI-based radiomics model can improve the predictive performance of postlaminar optic nerve invasion in retinoblastoma

OBJECTIVES

To develop an MRI-based radiomics model to predict postlaminar optic nerve invasion (PLONI) in retinoblastoma (RB) and compare its predictive performance with subjective radiologists' assessment.

METHODS

We retrospectively enrolled 124 patients with pathologically proven RB (90 in training set and 34 in validation set) who had MRI scans before surgery. A radiomics model for predicting PLONI was developed by extracting quantitative imaging features from axial T2W images and contrast-enhanced T1W images in the training set. The Kruskal-Wallis test, least absolute shrinkage and selection operator regression, and recursive feature elimination were used for feature selection, where upon a radiomics model was built with a logistic regression (LR) classifier. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve and the accuracy were assessed to evaluate the predictive performance in the training and validation set. The performance of the radiomics model was compared to radiologists' assessment by DeLong test.

RESULTS

The AUC of the radiomics model for the prediction of PLONI was 0.928 in the training set and 0.841 in the validation set. Radiomics model produced better sensitivity than radiologists' assessment (81.1% vs  43.2% in training set, 82.4vs 52.9% in validation set). In all 124 patients, the AUC of the radiomics model was 0.897, while that of radiologists' assessment was 0.674 (p < 0.001, DeLong test).

CONCLUSION

MRI-based radiomics model to predict PLONI in RB patients was shown to be superior to visual assessment with improved sensitivity and AUC, and may serve as a potential tool to guide personalized treatment.

Aqueous seeding in retinoblastoma: Classification and clinicopathological correlation

PURPOSE

To correlate clinical types of aqueous seeds with histopathological characteristics in primarily enucleated eyes with retinoblastoma (RB).

DESIGN

Retrospective study PARTICIPANTS: Twenty-five patients with RB METHODS: Clinicopathological correlation of aqueous seeds in 25 eyes that underwent primary enucleation and had evidence of aqueous seeds MAIN OUTCOME MEASURES: Histopathological characteristics of aqueous seeds RESULTS: All 25 enucleated eyes were classified as group E RB based on International Classification of Intraocular Retinoblastoma. Clinically, type 1 aqueous seeds were noted in 9 (36%), type 2 in 8 (32%), and type 3 in 8 (32%). Based on histopathology, type 1 seeds were individual tumor cells admixed with macrophages and non-viable tumor cells; type 2 seeds were spheres and are classified into two subtypes a) Spheres without central necrosis containing solid clusters of tumor cells b) Spheres with central necrosis containing central core of necrotic cells surrounded by viable tumor cells; and type 3 seeds were tumor cells admixed with macrophages and RBCs that sediment into angle. Aqueous seeding involved both anterior (n=25; 100%) and posterior chambers (n=18; 72%). Significant intraocular tissue (Schlemm's canal, trabecular meshwork, ciliary body, choroid, optic nerve, sclera) infiltration of RB was noted in 23 (92%) cases. Compared to type 1 and 2 seeds, patients with type 3 seeds were more commonly associated with ciliary body infiltration (41% vs 88%; p=0.04). Over a mean follow-up period of 57 months (median, 49 months; range, <1 to 175 months), metastasis and death was noted in 3 (12%) patients.

CONCLUSION

Similar to vitreous seeds in RB, aqueous seeds have three distinct histopathological types. Posterior chamber seeds are noted in 72% cases presenting with anterior chamber seeds indicating the need for treatment of both the chambers whenever conservative treatment is attempted in suitable cases. Most (92%) cases with primary aqueous seeding are associated with other high-risk histopathology features, suggesting a cautious approach for conservative management in these cases.

Changes in Treatment Patterns and Globe Salvage Rate of Advanced Retinoblastoma in Korea: Efficacy of Intra-Arterial Chemotherapy

(1) Background: To analyze changes in treatment patterns for advanced retinoblastoma over time and differences in globe salvage rates; (2) Methods: Retrospective, observational case-control study of 97 eyes of 91 patients with advanced retinoblastoma (Group D and E).; (3) Results: Patients were divided into two groups based on whether they were treated before or after intraarterial chemotherapy (IAC) was introduced in our center in 2010. Before 2010, primary treatment pattern was enucleation, which was performed in 57.6% of cases, whereas primary treatment pattern after 2010 was IAC combined with intravenous chemotherapy (IVC), which was performed in 78.1%. Intravitreal chemotherapy (IVitC) has been performed to treat vitreous and subretinal seeding since 2015. The 5-year globe salvage rate of IVC alone was 24.0% for Group D and 0% for Group E, whereas that of IVC–IAC was 50.4% for Group D and 49.7% for Group E. Whether IVitC was performed or not did not significantly contribute to globe salvage rate. There was one metastatic death in the IVC alone group.; (4) Conclusions: Primary treatment pattern changed from enucleation to IAC-based treatment, which can now save nearly half of eyes with advanced retinoblastoma with excellent safety profile and survival rate.

Defining High-Risk Retinoblastoma: A Multicenter Global Survey

Importance

High-risk histopathologic features of retinoblastoma are useful to assess the risk of systemic metastasis. In this era of globe salvage treatments for retinoblastoma, the definition of high-risk retinoblastoma is evolving.

Objective

To evaluate variations in the definition of high-risk histopathologic features for metastasis of retinoblastoma in different ocular oncology practices around the world.

Design, Setting, and Participants

An electronic web-based, nonvalidated 10-question survey was sent in December 2020 to 52 oncologists and pathologists treating retinoblastoma at referral retinoblastoma centers.

Intervention

Anonymized survey about the definition of high-risk histopathologic features for metastasis of retinoblastoma.

Main Outcomes and Measures

High-risk histopathologic features that determine further treatment with adjuvant systemic chemotherapy to prevent metastasis.

Results

Among the 52 survey recipients, the results are based on the responses from 27 individuals (52%) from 24 different retinoblastoma practices across 16 countries in 6 continents. The following were considered to be high-risk features: postlaminar optic nerve infiltration (27 [100%]), involvement of optic nerve transection (27 [100%]), extrascleral tissue infiltration (27 [100%]), massive (≥3 mm) choroidal invasion (25 [93%]), microscopic scleral infiltration (23 [85%]), ciliary body infiltration (20 [74%]), trabecular meshwork invasion (18 [67%]), iris infiltration (17 [63%]), anterior chamber seeds (14 [52%]), laminar optic nerve infiltration (13 [48%]), combination of prelaminar and laminar optic nerve infiltration and minor choroidal invasion (11 [41%]), minor (<3 mm) choroidal invasion (5 [19%]), and prelaminar optic nerve infiltration (2 [7%]). The other histopathologic features considered high risk included Schlemm canal invasion (4 [15%]) and severe anaplasia (1 [4%]). Four respondents (15%) said that the presence of more than 1 high-risk feature, especially a combination of massive peripapillary choroidal invasion and postlaminar optic nerve infiltration, should be considered very high risk for metastasis.

Conclusions and Relevance

Responses to this nonvalidated survey conducted in 2020-2021 showed little uniformity in the definition of high-risk retinoblastoma. Postlaminar optic nerve infiltration, involvement of optic nerve transection, and extrascleral tumor extension were the only features uniformly considered as high risk for metastasis across all oncology practices. These findings suggest that the relevance about their value in the current scenario with advanced disease being treated conservatively needs further evaluation; there is also a need to arrive at consensus definitions and conduct prospective multicenter studies to understand their relevance.

High-Risk Histopathologic Features of Retinoblastoma Treated at a Tertiary Hospital in West Java, Indonesia

PURPOSE

To evaluate the histopathological characteristics of clinically advanced retinoblastoma (RB) and its relationship with tumor differentiation.

METHODS

This was a cross-sectional study of primary enucleated group D/E intraocular RB using medical records from 2017 to 2020 in a tertiary referral hospital. Cases with incomplete histopathological results were excluded. Tumors were classified into well, moderately, and poorly differentiated and undifferentiated. High-risk histopathological features were classified as per Thaung and Karaa [Community Eye Health. 2018;31(101):17-3].

RESULTS

This study included 121 patients (129 eyes), of which 32.2% were diagnosed at 25-36 months. High-risk features (HRFs) were found in 100/129 eyes, and of 73 complete histopathological results, the 2 most common HRFs were postlaminar optic nerve invasion and massive choroidal invasion. RB was poorly differentiated in 69.9% and well differentiated in 12.3% of eyes. There was no statistically significant association between any HRFs and tumor differentiation, with age >2 years associated with tumor differentiation (p < 0.05).

CONCLUSION

The frequency of HRFs is 77.5% of primary enucleated eyes, mainly poorly and undifferentiated cells, particularly in children aged >2 years old.

Eye-Preserving Therapies for Advanced Retinoblastoma: A Multicenter Cohort of 1678 Patients in China

PURPOSE

This study attempted to estimate the impact of eye-preserving therapies for the long-term prognosis of patients with advanced retinoblastoma with regard to overall survival and ocular salvage.

DESIGN

Retrospective cohort study covering all 31 provinces (38 retinoblastoma treating centers) of mainland China.

PARTICIPANTS

One thousand six hundred seventy-eight patients diagnosed with group D or E retinoblastoma from January 2006 through May 2016.

METHODS

Chart review was performed. The patients were divided into primary enucleation and eye-preserving groups, and they were followed up for survival status. The impact of initial treatment on survival was evaluated by Cox analyses.

MAIN OUTCOME MEASURES

Overall survival and final eye preservation.

RESULTS

After a median follow-up of 43.9 months, 196 patients (12%) died, and the 5-year overall survival was 86%. In total, the eyeball preservation rate was 48%. In this cohort, 1172 patients (70%) had unilateral retinoblastoma, whereas 506 patients (30%) had bilateral disease. For patients with unilateral disease, 570 eyes (49%) underwent primary enucleation, and 602 patients (51%) received eye-preserving therapies initially. During the follow-up (median, 45.6 months), 59 patients (10%) from the primary enucleation group and 56 patients (9.3%) from the eye-preserving group died. Multivariate Cox analyses indicated no significant difference in overall survival between the 2 groups (hazard ratio [HR], 1.25; 95% confidence interval [CI], 0.85-1.84; P = 0.250). For patients with bilateral disease, 95 eyes (19%) underwent primary enucleation, and 411 patients (81%) received eye-preserving therapies initially. During the follow-up (median, 40.1 months), 12 patients (13%) from the primary enucleation group and 69 patients (17%) from the eye-preserving group died. For bilateral retinoblastoma with the worse eye classified as group E, patients undergoing primary enucleation exhibited better overall survival (HR, 2.35; 95% CI, 1.10-5.01; P = 0.027); however, this survival advantage was not evident until passing 22.6 months after initial diagnosis.

CONCLUSIONS

Eye-preserving therapies have been used widely for advanced retinoblastoma in China. Patients with bilateral disease whose worse eye was classified as group E and who initially underwent eye-preserving therapies exhibited a worse overall survival. The choice of primary treatment for advanced retinoblastoma should be weighed carefully.

Efficacy, Toxicity, and Pharmacokinetics of Intra-Arterial Chemotherapy Versus Intravenous Chemotherapy for Retinoblastoma in Animal Models and Patients

Purpose

Through controlled comparative rabbit experiments and parallel patient studies, our purpose was to understand mechanisms underlying differences in efficacy and toxicity between intra-arterial chemotherapy (IAC) and intravenous chemotherapy (IVC).

Methods

In rabbits, ocular tissue drug levels were measured following IAC and IVC. Retinal toxicity was assessed using electroretinography, fluorescein angiography, optical coherence tomography (OCT) and OCT angiography. Efficacy to eradicate retinoblastoma orthotopic xenografts was compared. In IAC and IVC patients, we measured blood carboplatin pharmacokinetics and compared efficacy and toxicity.

Results

In rabbits receiving IAC, maximum carboplatin levels were 134 times greater in retina (P = 0.01) and 411 times greater in vitreous (P < 0.001), and total carboplatin (area under the curve) was 123 times greater in retina (P = 0.005) and 131 times greater in vitreous (P = 0.02) compared with IVC. Melphalan levels were 12 times greater (P = 0.003) in retina and 26 times greater in vitreous (P < 0.001) for IAC. Blood levels were not different. IAC melphalan (but not IV melphalan or IV carboplatin, etoposide, and vincristine) caused widespread apoptosis in retinoblastoma xenografts but no functional retinal toxicity or cytopenias. In patients, blood levels following IVC were greater (P < 0.001) but, when adjusted for treatment dose, were not statistically different. Per treatment cycle in patients, IVC caused higher rates of anemia (0.32 ± 0.29 vs. 0.01 ± 0.04; P = 0.0086), thrombocytopenia (0.5 ± 0.42 vs. 0.0 ± 0.0; P = 0.0042), and neutropenia (0.58 ± 0.3 vs. 0.31 ± 0.25; P = 0.032) but lower treatment success rates (P = 0.0017).

Conclusions

The greater efficacy and lower systemic toxicity with IAC appear to be attributable to the greater ocular-to-systemic drug concentration ratio compared with IVC.

Translational Relevance

Provides an overarching hypothesis for a mechanism of efficacy/toxicity to guide future drug development.

Lenticular changes in eyes with advanced intraocular retinoblastoma: A histopathological study of 48 enucleated eyes

PURPOSE

To evaluate the lenticular changes in advanced intraocular retinoblastoma (RB) and identify the risk factors for cataract in these eyes.

METHODS

Retrospective analysis of 48 primary enucleations.

RESULTS

All enucleated eyes were classified either as group D (n = 7; 15%) or group E (n = 41; 85%) tumors based on the International Classification of Intraocular Retinoblastoma. Of the 48 enucleated eyes with RB, cataract was noted clinically in only 5 (18%) cases, while histopathology revealed cataractous changes in 28 (58%) cases. Based on histopathology, the cataractous changes included anterior subcapsular cataract (n = 10; 36%), cortical cataract (n = 6; 21%), posterior subcapsular cataract (n = 10; 36%) and both anterior and posterior subcapsular cataract (n = 2; 7%). Based on multivariate logistic regression, only increased area of necrosis on histopathology was the significant (p = .009) factor predictive of cataractous changes in lens with an odds ratio of 1.08.

CONCLUSION

Eyes with advanced RB can harbor cataract in 58% cases, though most of these are subclinical. Clinically significant cataract may be evident in only 18% cases. Increased tumor necrosis is associated with the development of cataractous changes in RB cases.

Intraarterial Chemotherapy for Retinoblastoma - Initial Experiences of a German Reference Centre

BACKGROUND

Adequate management of retinoblastoma requires a multidisciplinary and individual approach to treatment. Intraarterial chemotherapy (IAC) is one of the most commonly used treatment modalities, and enables supraselective application of chemotherapy via the ophthalmic artery and is now established in almost all treatment centres. However, published treatment success rates are heterogeneous. There are some unanswered issues regarding sight-threatening ocular complications and the long-term occurrence of secondary malignancies and metastatic disease. The objective of the present study is to analyse the results of a German national reference centre.

METHODS

Retrospective analysis of all children with an indication for at least one IAC from April 2010 to April 2020. IAC was used either as primary or recurrence therapy. Obligatory follow-up was at least 6 months.

RESULTS

137 eyes of 127 children with an indication for IAC could be included. 12 eyes with a follow-up of less than 6 months and 37 eyes in which IAC was technically not feasible were excluded. In summary, 88 eyes of 79 children were finally analysed. Mean follow-up was 38 months, ranging from 7 to 117 months. In total, 195 procedures were completed. In 30 eyes (34.1%) IAC was conducted as primary and in 58 (65.9%) as secondary therapy. There was an initial IAC treatment response in 75 eyes (85.2%) with a recurrence-free rate of 61.3%. Eye salvage rate was 68.1% with 28 enucleated eyes in total. Ocular complications were observed in 36 eyes (40.9%), with 19 eyes (21.6%) showing severe sight-threatening and 11 eyes (12.5%) presenting minor non-sight-threatening toxic reactions. During follow-up, 1 child developed a secondary malignancy, 1 child developed metastasis and 1 child died as a consequence of trilateral retinoblastoma.

CONCLUSION

In summary, IAC is a potent modality for retinoblastoma treatment and has been very successful, even in advanced disease and heavily pretreated eyes. However, ocular complications should be taken in consideration, especially when the only seeing eye is treated. Long term incidences of secondary malignancies and metastatic diseases should be further investigated in prospective studies.

Aqueous seeding in intraocular retinoblastoma: A review

The management of retinoblastoma is complex. With increasing treatment modalities and increasing experience with each treatment modality, the globe salvage rates have drastically improved with time. Aqueous seeding in an eye with retinoblastoma is classified as group E based on International Classification of Intraocular Retinoblastoma, and most group E eyes were enucleated a decade earlier. Newer modalities of treatment have improved the globe salvage rates in group E eyes including those with aqueous seeding. Various globe salvage treatment modalities attempted for the management of aqueous seeds include external beam radiotherapy, plaque radiotherapy, intra-arterial chemotherapy, periocular chemotherapy, intravitreal chemotherapy and intracameral chemotherapy. Of all treatment modalities, intracameral chemotherapy holds promise for the management of aqueous seeds in selected patients, but it should be done with the utmost care by a trained ocular oncologist. Enucleation is still the preferred modality of treatment for eyes with advanced retinoblastoma and anterior segment invasion. This review focuses on the current evidence on aqueous seeding, highlighting the pathogenesis, classification, clinical presentation, treatment and outcomes.

A New Rapidly Growing Dome-Shaped Choroidal Lesion in an Eye with Treated Retinoblastoma

Background

To describe an extensive untreatable choroidal metastasis by retinoblastoma in the treated patient which was clinically indistinguishable from regular tumor recurrence.

Methods

A 24-month-old girl without a family history of retinoblastoma (RB) was discovered to have group C RB in her right eye and group D in her left eye. The patient received 12 cycles of intravenous chemotherapy, intra-arterial chemotherapy (IAC), and intravitreal chemotherapy for the left eye and focal adjuvant therapy (laser thermotherapy and cryotherapy) for both eyes. Six months after the last treatment, fundus examination showed a regressed tumor in both eyes. Ten months after the last treatment, except for in addition to tumor recurrence, rising intraocular pressure was noticed in the left eye. While doing IAC for the left eye, a very rapid growing yellowish dome-shaped mass was found which had doubled in size in two weeks. Enucleation was considered for her.

Results

Pathology evaluation of the enucleated eye revealed a very massive dome-shaped choroidal metastasis invasion with poorly differentiated RB tumor. Prophylactic systemic chemotherapy was performed for the patient.

Conclusion

Choroidal metastasis in RB patients is often diagnosed based on pathology reports, but it may rarely be seen in clinical examinations especially if the pattern of tumor recurrence and growth is abnormal.

Clinical outcomes and prognosis of Thai retinoblastoma patients

BACKGROUND

Retinoblastoma (RB) outcomes in Thailand are unfavorable compared to those of developed countries. This study aims to determine whether the clinical outcomes of patients with RB significantly improved after the implementation of new therapeutic approaches and which clinical factors affect survival and globe-saving outcomes.

METHODS

The medical records of patients newly diagnosed with RB and treated at Siriraj Hospital between January 2005 and December 2018 were reviewed retrospectively. Clinical data, treatments, and outcomes were collected and analyzed.

RESULTS

In 194 eyes (144 patients), leukocoria was the most common presenting feature (76.8%); 129 (66.5%) eyes were staged in group E of the International Classification of Intraocular Retinoblastoma. Of the 149 enucleated eyes, 35 had high-risk histopathological features, mostly choroidal invasion; 45 eyes (23.2%) could be salvaged. The 5-year overall survival rate was 90.3%, an improvement compared to the previous study. The 5-year enucleation-free survival rates of Groups A and B, C, D and E were 100%, 83.1%, 36.7% and 16.6% respectively. Factors associated with a lower survival rate were interval from symptom onset to diagnosis >3 months (hazard ratio (HR): 5.8: 95% confidence interval (CI): 1.637, 20.579) and buphthalmos (HR: 12.57: 95% CI: 3.936, 40.153). Factors associated with high-risk features were secondary glaucoma (HR: 11.016: 95% CI: 1.24, 98.10) and pseudohypopyon (HR: 14.110: 95% CI: 2.16, 92.05).

CONCLUSIONS

Survival rates and globe-saving rates appear to have improved; however, advanced-stage presentation remains the major hindrance. Further studies with a larger cohort and longer follow-up are warranted.

Histopathological assessment of optic nerve invasion guided by radiological findings in enucleated globes with retinoblastoma

Background

Optic nerve (ON) invasion is an important high-risk feature, and an indicator for neoadjuvant chemotherapy and prognosis. We aim through this study to correlate the detected-ON invasion by Magnetic resonance imaging (MRI) with the corresponding confirmed histopathological level of invasion.

Methods

A retrospective study of enucleated globes with the diagnosis of retinoblastoma received in the histopathology department(s) from January 2015 to December 2016 (2 years). Slides were reviewed for ON invasion assessment, charts were reviewed for basic demographic data. All patients underwent MRI under sedation upon diagnosis and MRI findings were collected for the above correlation.

Results

A total of 38 patients were included: 21 males and 17 females. 29 (77.3%) had unilateral involvement, 7 (18.4%) had bilateral involvement and 2 cases had trilateral disease. The overall mean age at diagnosis was 22.63 ± 15.15 months. Histopathological examination revealed ON invasion in 28 cases (74%) distributed as follows: prelaminar (31.6%), laminar (18.4%), and post-laminar (23.7%). MRI confirmed post-laminar ON invasion in 8 cases (true positive) but failed to detect this in 1 case. Additionally, MRI detected another 8 cases of ON invasion that were false positive on histopathology (accuracy: 63.3%; sensitivity: 88.9%; specificity: 72.4%; Positive predictive value (PPV): 50%; Negative predictive value (NPV): 95.5%).

Conclusions

MRI is found to be less sensitive in evaluating prelaminar and laminar ON invasion (0.0 and 42.9%) compared to post-laminar invasion (88.9%). MRI has generally better specificity in detecting ON invasion irrespective of the invasion level. In our study, obtaining deeper and/or additional histologic sections from the other surface of the tissue block in cases where a post-laminar ON invasion by MRI is found but not confirmed histopathologically in routine sections is essential to avoid missing such an important high-risk feature.

Retinoblastoma: Etiology, Modeling, and Treatment

Retinoblastoma is a retinal cancer that is initiated in response to biallelic loss of RB1 in almost all cases, together with other genetic/epigenetic changes culminating in the development of cancer. RB1 deficiency makes the retinoblastoma cell-of-origin extremely susceptible to cancerous transformation, and the tumor cell-of-origin appears to depend on the developmental stage and species. These are important to establish reliable preclinical models to study the disease and develop therapies. Although retinoblastoma is the most curable pediatric cancer with a high survival rate, advanced tumors limit globe salvage and are often associated with high-risk histopathological features predictive of dissemination. The advent of chemotherapy has improved treatment outcomes, which is effective for globe preservation with new routes of targeted drug delivery. However, molecularly targeted therapeutics with more effectiveness and less toxicity are needed. Here, we review the current knowledge concerning retinoblastoma genesis with particular attention to the genomic and transcriptomic landscapes with correlations to clinicopathological characteristics, as well as the retinoblastoma cell-of-origin and current disease models. We further discuss current treatments, clinicopathological correlations, which assist in guiding treatment and may facilitate globe preservation, and finally we discuss targeted therapeutics for future treatments.

Full-width postlaminar optic nerve tumor invasion of retinoblastoma as risk-factor for leptomeningeal spread of retinoblastoma. A case report and review of the literature

We present a 6-year-old boy with unilateral retinoblastoma of the left eye. MRI showed an intraocular tumor that extended into the optic nerve beyond the lamina cribrosa. The affected eye was enucleated and the optic nerve resection margin proved to be free. Following protocol, this patient received six courses of adjuvant systemic chemotherapy. Unfortunately, after 5 months this patient returned with the leptomeningeal spread of the tumor and died quickly thereafter.Histopathologic analysis of the enucleated eye and distal optic nerve revealed that the postlaminar tumor cells occupied the entire width of the optic nerve, extending all the way up to the pia mater, whereas, more often the tumor invasion is restricted to the center of the optic nerve. This was also visible on the MR images where contrast enhancement occupied the entire nerve width. A resection margin with tumor cells is recognized as a risk factor for metastasis, but perhaps the proximity of tumor cells to the leptomeninges should also be judged with caution as a potential increased risk for metastatic spread.

Tumour size criteria for Group D and E eyes in the International Classification System for Retinoblastoma: effects on rates of globe salvage and high-risk histopathologic features

PURPOSE

To determine the significance of large tumour size as a criteria for classifying advanced intraocular retinoblastoma, analysing rates of globe survival and high-risk (HE) histopathologic features.

METHODS

Retrospective chart review of 212 eyes diagnosed with Group D (111 eyes) or Group E (101 eyes) retinoblastoma in at least one eye from January 1, 2006 to December 31, 2016 using the Los Angeles (LA) Classification System (no tumour size criteria for Group E). The 111 Group D tumours were then reclassified to Group E using 10, 12, 14, 16, 18 mm tumour size criteria, as determined by ultrasound or magnetic resonance imaging dimensions.

RESULTS

For eyes in the original LA classification, 66.7% of Group D and 10.5% of Group E eyes undergoing globe preservation therapy avoided enucleation or radiotherapy (p < 0.0001; median follow-up of 33.0 months). In the LA classification, 8.5% of Group D and 26.3% of Group E enucleated globes had HE histopathologic features (p = 0.0065). When Group D eyes with tumours meeting the size criteria were reclassified to Group E, 65.7-74.4% of Group D and 16.1-36.7% of Group E eyes avoided enucleation or radiotherapy. Applying the tumour size criteria, 0-10.9% of Group D and 20.7-23.8% of Group E eyes had HE histopathologic features.

CONCLUSION

Our retrospective analysis suggests that a large tumour size criteria for Group E retinoblastoma have no clinical basis, given that the LA classification system provided the greatest separation in globe salvage rates between Group D and E eyes. The LA classification system was also able to show a statistically significant difference in the rates of HE histopathologic features between Group D and E eyes. To avoid discrepancies in the literature, we recommend that centres use one uniform system for classifying advanced intraocular retinoblastoma.

Clinical Features and Long-Term Follow-Up of Patients with Retinoblastoma in Turkish Children Older Than 5 Years of Age

Purpose

The diagnosis and management of retinoblastoma can be difficult in older children. This study reports the clinical features and long-term outcomes of such patients in a Turkish patient population.

Methods

Medical records of 18 patients, between January 1992 and December 2017, were reviewed retrospectively.

Results

Of 298 consecutive patients with retinoblastoma, 18 (6%) were at the age of 5 years and older. The median age at diagnosis was 9 years (range, 5–18 years). Misdiagnosis was noted in 8 patients (44.4%). Treatment options included enucleation in 16 patients (88.8%), adjuvant systemic chemotherapy in 3 (16.6%), intra-arterial chemotherapy in one (5.5%), and additional orbital irradiation in one (5.5%). After a median follow-up of 97 months (range, 6–252 months), all patients survived without any recurrence.

Conclusions

Our series showed that 6% of patients with retinoblastoma were 5 years of age and older. Over a 15-year period, ocular salvage rate of 11.2% and survival rate of 100% were attained.

Establishment of a formal program for retinoblastoma: Feasibility of clinical coordination across borders and impact on outcome

Retinoblastoma is an ocular tumor that occurs in young children, in either heritable or sporadic manner. The relative rarity of retinoblastoma, and the need for expensive equipment, anesthesia, and pediatric ophthalmologic expertise, are barriers for effective treatment in developing countries. Also, with an average age-adjusted incidence of two to five cases per million children, patient number limits development of local expertise in countries with small populations. Lebanon is a small country with a population of approximately 4.5 million. In 2012, a comprehensive retinoblastoma program was formalized at the Children's Cancer Institute (CCI) at the American University of Beirut Medical Center, and resources were allocated for efficient interdisciplinary coordination to attract patients from neighboring countries such as Syria and Iraq, where such specialized therapy is also lacking. Through this program, care was coordinated across hospitals and borders such that patients would receive scheduled chemotherapy at their institution, and monthly retinal examinations and focal laser therapy at the CCI in Lebanon. Our results show the feasibility of successful collaboration across borders, with excellent patient and physician adherence to treatment plans. This was accompanied by an increase in patient referrals, which enables continued expertise development. However, the majority of patients presented with advanced intraocular disease, necessitating enucleation in 90% of eyes in unilateral cases, and more than 50% of eyes in bilateral cases. Future efforts need to focus on expanding the program that reaches to additional hospitals in both countries, and promoting early diagnosis, for further improvement of globe salvage rates.

Diagnosis of Postlaminar Optic Nerve Invasion in Retinoblastoma With MRI Features

BACKGROUND

Retinoblastomas (RBs) with postlaminar optic nerve invasion (PLONI) increases the risk of local recurrence or systemic metastasis. Most MRI studies on PLONI focused on optic nerve enhancement and tumor size, with reported relatively high specificity (84-98%) but low sensitivity (37-78%), which shows room for improvement, especially with regard to sensitivity.

PURPOSE

To evaluate the diagnostic performance for detecting PLONI with RB using MRI features.

STUDY TYPE

Retrospective.

POPULATION

Fifty patients with histopathologic PLONI and 70 patients without PLONI of RB.

FIELD STRENGTH/SEQUENCE

1.5T and 3.0T, precontrast axial T₁ -weighted and T₂ -weighted, postcontrast axial, coronal and oblique-sagittal T₁ -weighted.

ASSESSMENT

The eyes were histopathologically analyzed and the preoperative MRI features of the eyes were independently evaluated by three observers.

STATISTICAL TESTS

MRI features suggesting the presence of PLONI were identified by univariate and multivariable analysis. Receiver operating characteristic curve (ROC) and the area under the curve (AUC) were used to analyze diagnostic performance.

RESULTS

Significant independent diagnostic factors for PLONI include: 1: Bilateral tumor (odds ratio [OR], 15.32; 95% confidence interval [CI]: 1.63-143.51); 2: Tumor with total coverage of the optic disk (OR, 6.43; 95% CI: 1.04-39.79); and 3: Optic nerve enhancement (OR, 8.43; 95% CI: 3.50-20.31). On the other hand, isointense signal of tumor on T₂ WI (OR, 0.30; 95% CI: 0.12-0.75) was an independent diagnostic factor in excluding PLONI. ROC analysis showed AUC of 0.84 (95% CI: 0.77-0.91, P < 0.0001) for PLONI. Based on the cutoff of maximum Youden index, the sensitivity, specificity, and accuracy were 82%, 73%, and 77%, respectively.

DATA CONCLUSION

MRI features of RB showed a strong association with PLONI. The model of MRI features demonstrated promising diagnostic performance in detecting PLONI.

LEVEL OF EVIDENCE

4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:1045-1052.

Treatment of Nonmetastatic Unilateral Retinoblastoma in Children

Importance

Multi-institutional collaborative studies that include large patient populations for the management of retinoblastoma with histopathological risk factors could provide important information for patient management.

Objective

To evaluate the implementation of a strategy for the management of nonmetastatic unilateral retinoblastoma in children based on standardized diagnostic and treatment criteria.

Design, Setting, and Participants

This single-arm prospective study applied a strategy based on a single-center experience. The setting was a multicenter study in Latin America (Grupo de America Latina de Oncologia Pediatrica [GALOP]). Participants were children with nonmetastatic unilateral retinoblastoma (staged with the International Retinoblastoma Staging System). The study opened on July 1, 2008, and closed on December 31, 2014. Follow-up was updated until June 30, 2017.

Interventions

Stage 0 patients (without enucleation) were given conservative therapy without a protocol. Stage I patients (with enucleation and no residual tumor) were divided into a high-risk group (retrolaminar invasion and/or scleral invasion) and a low-risk group (all remaining patients). High-risk children received adjuvant chemotherapy with 4 alternating cycles of regimen 1 (cyclophosphamide [65 mg/kg/d] [plus sodium-2-mercaptoethane sulfonate], idarubicin hydrochloride [10 mg/m2/d], and vincristine sulfate [0.05 mg/kg/d]) and 4 cycles of regimen 2 (carboplatin [500 mg/m2/d, days 1 and 2] and etoposide [100 mg/m2/d, days 1-3]). Low-risk children did not receive adjuvant therapy. Children with buphthalmia received neoadjuvant and adjuvant chemotherapy for a total of 8 cycles.

Main Outcomes and Measures

Probability of event-free survival (extraocular relapse and death from any cause were considered events).

Results

Among 187 children registered in the study, 175 were evaluable (92 [52.5%] female; median age, 22 months; age range, 3-100 months). Forty-two were stage 0 children, 84 were stage I low-risk children, and 42 were stage I high-risk children; there were 7 children in the buphthalmia group. With a median follow-up of 46 months, the 3-year probability of event-free survival was 0.97 (95% CI, 0.94-0.99), and the probability of overall survival was 0.98 (95% CI, 0.94-1.00). Stage 0 patients had no events, stage I low-risk patients had 1 event (orbital relapse treated with second-line therapy), stage I high-risk patients had 2 events (1 central nervous system relapse and 1 death from sepsis), and the buphthalmia group had 1 event (orbital relapse, followed by central nervous relapse and death).

Conclusions and Relevance

Adjuvant therapy may be effective for high-risk unilateral retinoblastoma but is toxic, and neoadjuvant chemotherapy for buphthalmus appears feasible.

Delayed Enucleation With Neoadjuvant Chemotherapy in Advanced Intraocular Unilateral Retinoblastoma: AHOPCA II, a Prospective, Multi-Institutional Protocol in Central America

PURPOSE

Treatment abandonment because of enucleation refusal is a limitation of improving outcomes for children with retinoblastoma in countries with limited resources. Furthermore, many children present with buphthalmos and a high risk of globe rupture during enucleation. To address these unique circumstances, the AHOPCA II protocol introduced neoadjuvant chemotherapy with delayed enucleation.

PATIENTS AND METHODS

Patients with advanced unilateral intraocular disease (International Retinoblastoma Staging System [IRSS] stage I) were considered for upfront enucleation. Those with diffuse invasion of the choroid, postlaminar optic nerve, and/or anterior chamber invasion received six cycles of adjuvant chemotherapy (vincristine, carboplatin, and etoposide). Patients with buphthalmos and those with a perceived risk for enucleation refusal and/or abandonment were given two to three cycles of chemotherapy before scheduled enucleation followed by adjuvant chemotherapy to complete six cycles, regardless of pathology.

RESULTS

A total of 161 patients had unilateral IRSS stage I disease; 102 underwent upfront enucleation, and 59 had delayed enucleation. The estimated 5-year abandonment-sensitive event-free and overall survival rates for the group were 0.81 ± 0.03 and 0.86 ± 0.03, respectively. The 5-year estimated abandonment-sensitive event-free survival rates for patients undergoing upfront and delayed enucleation were 0.89 ± 0.03 and 0.68 ± 0.06, respectively (P = .001). Compared with AHOPCA I, abandonment for patients with IRSS stage I retinoblastoma decreased from 16% to 4%.

CONCLUSION

AHOPCA describes the results of advanced intraocular retinoblastoma treated with neoadjuvant chemotherapy. In eyes with buphthalmos and patients with risk of abandonment, neoadjuvant chemotherapy can be effective when followed by enucleation and adjuvant chemotherapy. Our study suggests that this approach can save patients with buphthalmos from ocular rupture and might reduce refusal of enucleation and abandonment.

Intra-arterial chemotherapy in retinoblastoma - A paradigm change

Intra-arterial chemotherapy (IAC), also known as superselective ophthalmic artery chemotherapy or chemosurgery, is currently widely accepted as one of the primary treatment modalities for intraocular retinoblastoma worldwide. Following the introduction of the technique in 1998, IAC has evolved over the past decades to be safer and more effective. Accumulated evidence shows that IAC is more effective in providing eye salvage in group D and E retinoblastoma as compared to conventional systemic intravenous chemotherapy (IVC). In contrast to IVC, IAC has the added benefits of reduced overall treatment duration and minimal systemic toxicity. This review provides a comprehensive update on the history, technique, indications, contraindications, and outcome of IAC. We have also identified the strengths, weaknesses, opportunities and threats (SWOT analysis) of the technique in this review.

MicroRNA-503 serves an oncogenic role in retinoblastoma progression by directly targeting PTPN12

Numerous studies have demonstrated that microRNAs (miRNAs or miRs) are abnormally expressed in retinoblastoma (RB). miRNAs may serve a role in oncogene or tumor-suppressor activity in RB genesis and development by modulating various biological processes. miRNAs therefore, may be effective therapeutic targets for miRNA-based therapy in patients with RB. Recently it has been revealed that miR-503 may serve a role in various types of human cancer. However, the expression and functional roles of miR-503 are rarely reported in RB. In the current study, the expression of miR-503 was significantly upregulated in RB tissues and cell lines. In addition, Cell Counting Kit-8 and in vitro invasion assays were performed to assess cell proliferation and invasion, respectively. The results of the present study revealed that miR-503 inhibition impeded RB in vitro cell proliferation and invasion. Furthermore, protein tyrosine phosphatase nonreceptor type 12 (PTPN12) was demonstrated to be a direct target gene of miR-503 in RB cells. PTPN12 overexpression also led to the downregulation of miR-503 in RB cell proliferation and invasion. PTPN12 knockdown could therefore abrogate the effects of miR-503 downregulation in RB cells. In conclusion, the results demonstrated that miR-503 may serve a role in RB oncogenic activity progression by directly targeting PTPN12. Therefore, miR-503 may be a target for effective therapy in patients with RB.

Role of High-mobility Group Protein A Isoforms and Their Clinicopathologic Significance in Primary Retinoblastoma

BACKGROUND

High-mobility group proteins A (HMGA) are more abundant in rapidly dividing and transformed cells. These are a group of proteins regulating tumorigenesis and tumor invasion. Increased expression of HMGA1 and HMGA2 has been reported in various benign and malignant tumors. The aim of the present study was to analyze expression of HMGA1 and HMGA2 proteins in retinoblastoma.

METHODS

Protein expression of HMGA1 and HMGA2 in 80 formalin-fixed retinoblastoma tissues was performed by immunohistochemistry, and their mRNA expressions were analyzed on 40 fresh primary enucleated retinoblastoma samples by semiquantitative reverse transcription polymerase chain reaction. Results were then correlated with clinicopathologic parameters.

RESULTS

Immunohistochemical analysis of HMGA1 and HMGA2 was seen in 56.25% and 58.75% of retinoblastoma cases, respectively. mRNA expressions of HMGA1 and HMGA2 was found to be 57.55% and 62.5%, respectively. The mRNA results correlated well with immunostaining results. Expression of both HMGA1 and HMGA2 was significantly associated with choroidal invasion and poor tumor differentiation.

CONCLUSIONS

HMGA1 and HMGA2 proteins may contribute to tumorigenesis of Rb. Expression of HMGA1 and HMGA2 predicts poor prognosis and could serve as a therapeutic target in the management of RB. Further experiments are needed to determine the role of these proteins as therapeutic targets in tumorigenesis.

HIGH-RISK INTRAOCULAR RETINOBLASTOMA: Comparison Between Asian Indians and Americans From Two Major Referral Centers

PURPOSE

To identify the differences in the clinical and histopathologic features in eyes with advanced intraocular retinoblastoma in a developing country (India) versus a developed country (USA).

METHODS

Retrospective study.

RESULTS

Of 524 patients with retinoblastoma who underwent primary enucleation, 331 were from India, and 193 were from the USA. Asian Indians were older at presentation (35 months vs. 29 months; P = 0.02), had thicker tumors (13.8 mm vs. 12.4 mm; P = 0.0001) compared with Americans. High-risk intraocular retinoblastoma was more common in Asian Indians with a 2-fold greater risk compared with Americans (35% vs. 23%; odds ratio = 1.83; P = 0.003). Statistically significant differences in the histopathologic features (Asian Indians vs. Americans) included massive (≥3 mm) choroidal infiltration (17% vs. 6%; P = 0.0003) and optic nerve infiltration (48% vs. 15%; P = 0.0001). Asian Indians had a 5-fold greater risk of having optic nerve invasion (odds ratio = 5.45; P < 0.0001) and 3-fold greater risk of massive choroidal invasion (odds ratio = 2.80; P < 0.0001) compared with Americans. With appropriate use of adjuvant systemic chemotherapy, the difference in the rates of systemic metastasis (5% vs. 2%, P = 0.67) and related death in both countries (5% vs. 0%, P = 0.14) were not statistically significant.

CONCLUSION

High-risk intraocular retinoblastoma is more common in Asian Indians compared with Americans.

Conservative management of retinoblastoma: Challenging orthodoxy without compromising the state of metastatic grace. "Alive, with good vision and no comorbidity"

Retinoblastoma is lethal by metastasis if left untreated, so the primary goal of therapy is to preserve life, with ocular survival, visual preservation and quality of life as secondary aims. Historically, enucleation was the first successful therapeutic approach to decrease mortality, followed over 100 years ago by the first eye salvage attempts with radiotherapy. This led to the empiric delineation of a window for conservative management subject to a "state of metastatic grace" never to be violated. Over the last two decades, conservative management of retinoblastoma witnessed an impressive acceleration of improvements, culminating in two major paradigm shifts in therapeutic strategy. Firstly, the introduction of systemic chemotherapy and focal treatments in the late 1990s enabled radiotherapy to be progressively abandoned. Around 10 years later, the advent of chemotherapy in situ, with the capitalization of new routes of targeted drug delivery, namely intra-arterial, intravitreal and now intracameral injections, allowed significant increase in eye preservation rate, definitive eradication of radiotherapy and reduction of systemic chemotherapy. Here we intend to review the relevant knowledge susceptible to improve the conservative management of retinoblastoma in compliance with the "state of metastatic grace", with particular attention to (i) reviewing how new imaging modalities impact the frontiers of conservative management, (ii) dissecting retinoblastoma genesis, growth patterns, and intraocular routes of tumor propagation, (iii) assessing major therapeutic changes and trends, (iv) proposing a classification of relapsing retinoblastoma, (v) examining treatable/preventable disease-related or treatment-induced complications, and (vi) appraising new therapeutic targets and concepts, as well as liquid biopsy potentiality.

Bilateral advanced (group D or E) intraocular retinoblastoma: outcomes in 72 Asian Indian patients

PURPOSE

To study the clinical presentation, treatment, and outcomes of patients with bilateral advanced intraocular retinoblastoma.

METHODS

Retrospective case series of 72 patients.

RESULTS

The mean age at presentation was 19 months. Leukocoria (n = 49, 68%) was the most common presenting complaint. The tumors were classified as groups D (n = 60, 42%) or E (n = 84, 58%) based on the Philadelphia version of International Classification of Retinoblastoma (ICRB); groups D (n = 84, 58%) or E (n = 60, 42%) based on Children's Hospital Los Angeles version of International Classification of Intraocular Retinoblastoma (ICIoR); T2 (n = 116, 81%) or T3 (n = 28, 19%) based on 8th edition American Joint Committee Classification (AJCC). Systemic chemotherapy (n = 138, 96%) was the most common primary treatment modality. The chance of globe salvage was higher for group D based on ICRB (83%; odds ratio (OR) 7.73; 95% confidence interval (CI) 3.45-17.33) or ICIoR (81%; OR 12.75; 95% CI 5.74-28.34) and T2b (73%; OR 5.19; 95% CI 2.51-10.73) based on AJCC. Over a mean follow-up period of 59 months, tumor recurrence was noted in 42 (29%) eyes and globe salvage was achieved in 83 (58%) eyes. Of the 50 eyes where vision was recorded, vision of 20/200 or better was achieved in 24 (48%) eyes. There were events of leukemia (n = 1, 1%), pinealoblastoma (n = 1, 1%), systemic metastasis (n = 3, 4%), and death (n = 4, 6%) during the follow-up period.

CONCLUSION

Multimodality treatment allows globe salvage (58%) and vision salvage (48%) in eyes with advanced group D and E intraocular retinoblastoma.

MicroRNA‑504 targets AEG‑1 and inhibits cell proliferation and invasion in retinoblastoma

The dysregulation of microRNAs (miRNAs/miRs) has become increasingly recognized as a primary feature of retinoblastoma (RB). Furthermore, miRNAs have been demonstrated to be involved in the occurrence and development of RB. Therefore, it is crucial to investigate the expression profile and roles of miRNAs in RB in order to identify potential therapeutic targets to treat patients with RB. The expression profile and biological roles of miRNA‑504 (miR‑504) have been reported in numerous types of human cancer; however, the roles of miR‑504 in RB remain unknown. In the present study, it was demonstrated that miR‑504 expression was significantly decreased in RB tissues and cell lines. Functional analysis identified that resumption of miR‑504 expression suppressed cell proliferation and invasion in RB. Furthermore, astrocyte elevated gene‑1 (AEG‑1) was determined to be a direct target of miR‑504 in RB, and a negative correlation between miR‑504 and AEG‑1 mRNA expression levels was observed in RB tissues. Additionally, the tumor‑suppressing effects of miR‑504 overexpression in RB cells could be rescued by AEG‑1 upregulation. In conclusion, these results indicated a significant role of the miR‑504/AEG‑1 pathway in inhibiting the aggressiveness of RB, suggesting that this miRNA may be employed as a therapeutic target for the treatment of patients with this disease.

Analysis of the short-term curative effect of 356 cases of intraocular retinoblastoma in children

IMPORTANCE

Retinoblastoma (Rb) is the most common primary malignant intraocular cancer in children. Systemic chemotherapy combined with local therapy is safe and effective for intraocular Rb.

OBJECTIVE

To summarize the short-term outcomes of patients with Rb to provide evidence for optimizing treatment protocols and improving therapeutic safety and efficacy.

METHODS

The clinical data of 356 patients (486 eyes) with intraocular Rb admitted to our center from December 2009 to April 2017 were retrospectively analyzed. The measures included drug toxicity, eye-preservation rate, and survival rate, with an emphasis on safety and short-term efficacy. The date of last follow-up was 30 November, 2017.

RESULTS

The patients comprised 226 unilateral Rb and 130 bilateral Rb. Enucleation before chemotherapy was performed in 72 patients. Among the 174 patients with unilateral Rb, enucleation after chemotherapy was performed in 80 patients (46.0%), and the eye was not enucleated in 89 (51.1%); 68 eyes were preserved (68/114, 59.6%) in Group D and 20 eyes (20/59, 33.8%) in Group E. Among the 220 eyes in patients with bilateral Rb, enucleation after chemotherapy was performed for 35 eyes; the eye-preservation rate was 91.7% in Group C, 79.1% in Group D, and 52.1% in Group E. All patients developed grade II to IV myelosuppression after chemotherapy, among whom 18 patients (5%) requiring transfusion. Fourteen patients (3.9%) died of intracranial metastasis following self-elected discontinuation of treatment (n = 7). Patients were followed up for a median of 47 (range, 1-96) months. The expected 5-year overall survival rate was 95.3% (96.7% for unilateral Rb and 92.9% for bilateral Rb, P = 0.074).

INTERPRETATION

The VEC (vincristine, etoposide, and carboplatin) regimen with local treatment was safe for intraocular Rb. Intracranial metastasis remains the most common cause of Rb-related death.

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.