A Histopathologic Analysis of Eyes Primarily Enucleated for Advanced Intraocular Retinoblastoma From a Developing Country

Molecular Biological Research on the Pathogenic Mechanism of Retinoblastoma

Retinoblastoma (RB) is the most common intraocular malignant tumor in children, primarily attributed to the bi-allelic loss of the RB1 gene in the developing retina. Despite significant progress in understanding the basic pathogenesis of RB, comprehensively unravelling the intricate network of genetics and epigenetics underlying RB tumorigenesis remains a major challenge. Conventional clinical treatment options are limited, and despite the continuous identification of genetic loci associated with cancer pathogenesis, the development of targeted therapies lags behind. This review focuses on the reported genomic and epigenomic alterations in retinoblastoma, summarizing potential therapeutic targets for RB and providing insights for research into targeted therapies.

Management of Intraocular Retinoblastoma: ICMR Consensus Guidelines

Retinoblastoma (RB) is the most common childhood intraocular malignancy. Delayed presentation due to a lack of awareness and advanced intraocular tumors are a common scenario in low-middle income countries (LMICs). Remarkable treatment advances have been made in the past few decades allowing globe salvage in advanced intraocular RB (IORB) including systemic chemotherapy with focal consolidation and targeted treatments like intraarterial chemotherapy and intravitreal chemotherapy. However, a lack of availability and affordability limits the use of such advances in LMICs. External beam radiotherapy, despite risk of second cancers in RB with germline mutations, still remains useful for recalcitrant RB not responding to any other treatment. When choosing conservative treatment for advanced IORB, the cost and long duration of treatment, morbidity from multiple evaluation under anesthesias (EUAs), side effects of treatment and risk of treatment failure need to be taken into account and discussed with the parents. In this article, the authors discuss the ICMR consensus guidelines on the management of IORB.

Epidemiology, Diagnosis and Genetics of Retinoblastoma: ICMR Consensus Guidelines

Retinoblastoma (RB) is the most common intraocular tumor in childhood. It is mainly caused by mutations in both alleles of the RB1 tumor suppressor gene that is found on chromosome 13 and regulates the cell cycle. Approximately 8000 children are diagnosed with RB globally each year, with an estimated 1500 cases occurring in India. The survival rate of RB has improved to more than 90% in the developed world. Leukocoria and proptosis are the most common presenting features of RB in Asian Indian populations. Most cases of RB are diagnosed by fundus examination followed by ultrasound. The International Classification of Retinoblastoma is the most used scheme for the staging and classification of intraocular RB in India. Prenatal testing and preimplantation genetic testing for RB may be beneficial in high-risk families. Histopathologic risk factors such as massive choroidal invasion and post-laminar optic nerve help in predicting the occurrence of metastasis in children with RB, while presence of microscopic residual disease requires aggressive adjuvant treatment in eyes enucleated for group E RB. The review provides a consensus document on diagnosis and genetics of RB in India.

Correlation between clinical presentations, radiological findings and high risk histopathological features of primary enucleated eyes with advanced retinoblastoma at Queen Sirikit National Institute of Child Health: 5 years result

Purpose

To evaluate the correlation between clinical presentations, radiological findings and high risk histopathological features of primary enucleated eyes in patients with advanced retinoblastoma at a tertiary child hospital in Thailand.

Materials and methods

We retrospectively reviewed the medical records of patients who were treated with primary enucleation of tumor eyes between 2015–2020. Demographic data, radiological assessment, and histopathological findings were collected. The association between clinical presentations and high-risk histopathological features in the primary enucleated eyes were evaluated. The radiological findings, which showed characteristic of high risk features, were compared with the histopathological findings.

Results

Thirty-three enucleated eyes were enrolled in this study. The mean age at diagnosis was 23.12 months. Most patients had unilateral group E retinoblastoma, with no difference in sex and laterality of the eye. Leukocoria was the most common presentation, followed by proptosis and uveitis. Older age at presentation were statistically associated with post laminar cribrosa optic nerve invasion (P-value 0.0027) and high-risk histopathological features in enucleated eyes (P-value 0.0032). Clinical presentations with proptosis were statistically associated with post laminar cribrosa optic nerve invasion, while leukocoria and uveitis were statistically associated with anterior segment invasion. Unifocal intraocular mass with necrosis was the most common histopathological finding. High-risk features were found in 45% of primary enucleated eye. The sensitivity and specificity of magnetic resonance imaging (MRI) for detected optic nerve invasion in retinoblastoma patients were 75% and 54%, respectively.

Conclusion

Patients with unilateral retinoblastoma who presented with older age related to high-risk features after enucleation. Ophthalmic examination with slitlamp is the best way for detection of anterior segment invasion. Choroidal invasion was unable to predict with clinical presentation. MRI was the better imaging for detection of post laminar cribrosa optic nerve invasion.

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.

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.

Enucleated globes with advanced retinoblastoma: correlation of histopathological features and reclassification of tumors according to the 8th edition of the American Joint Committee on Cancer (AJCC)

PURPOSE

We aim to study certain histopathological characteristics of the retinoblastoma (RB) tumors in globes with clinically advanced RB, which can be correlated with the high-risk features including: tumor differentiation, growth pattern and focality. We also aim to reclassify the tumor pathologically in the analyzed cases according to the American Joint Committee on Cancer (AJCC) 8th edition in an attempt to compare the validity of this newest classification.

METHODS

Retrospective study of patients diagnosed with clinical RB of groups D and E during the period: January 2013 to December 2017 at King Khaled Eye Specialist Hospital (KKESH) and King Abdulaziz University Hospital (KAUH). Charts were reviewed for demographic and basic clinical data. Histopathological features (tumor differentiation, growth pattern, focality, seeding, and presence of choroidal invasion (focal versus massive), level of optic nerve (ON) invasion, anterior chamber invasion, scleral and extra-scleral extension, and finally the documented pathological tumors (pT) classification based on the AJCC 7th edition were collected.

RESULTS

We included 146 eyes with advanced retinoblastoma (groups D and E) from 104 patients. Gender distribution was almost equal with 54 males. Median age was 12 months (range 1-96 months), and a mean age was 17.1 ± 15.1 months. No family history was found in the majority (94.2%). Clinically, the most common presenting symptoms: leukocoria (73.3%), squint (33.6%) and least commonly proptosis (2.7%). A total of 106 enucleation specimens were reviewed. Degree of RB differentiation was: well differentiated (18%), moderate (30%), poor (35%), and undifferentiated (17%). The most common high-risk features were ON invasion (68%) with the majority being prelaminar in nature, choroidal invasion (45%) with more than half being massive, iris/trabecular meshwork (TM)/Schlemm's canal invasion (8.5%), and then intra-scleral/extra-scleral extension (5%). Less tumor differentiation doubles the relative risk of massive choroidal invasion (with 95% CI) with a statistically significant P value (P = 0.030). Endophytic RB was associated with vitreous seeding, while exophytic tumors were associated with subretinal seeding (P = 0.001) each. Ten cases with combined ON invasion (pre-laminar) and focal choroidal invasion were reclassified pT2a in the AJCC 8th edition instead of pT2b in the older 7th edition.

CONCLUSIONS

Our demographic and basic clinical data for advanced RB are comparable to other similar reports. The tumor growth pattern correlates well with the type of seeding observed in enucleated globes with RB. Less tumor differentiation is a relative risk of massive choroidal invasion. It is advocated to implement the AJCC 8th edition by ocular pathologists worldwide aiming to histopathologically classify the RB tumor in cases for selective adjuvant chemotherapy.

UHRF1 downmodulation enhances antitumor effects of histone deacetylase inhibitors in retinoblastoma by augmenting oxidative stress-mediated apoptosis

Identification of new genetic pathways or molecular targets that sensitize cancer cells to chemotherapeutic drugs may improve the efficacy of current chemotherapy. Here, we report that downmodulation of UHRF1 (ubiquitin-like with PHD and RING finger domains 1) in retinoblastoma (RB) cells increases the sensitivity to histone deacetylase (HDAC) inhibitors, augmenting apoptotic cell death. We found that UHRF1 depletion downregulates two redox-responsive genes GSTA4 (glutathione S-transferase α4) and TXN2 (thioredoxin-2) in RB cells, and increases the basal level of intracellular oxidative stress. Antioxidant treatment significantly reduced both basal and HDAC inhibitor-induced DNA damage and apoptosis in UHRF1-depleted cells. Knockdown of GSTA4 or TXN2 sensitized RB cells to HDAC inhibitors, demonstrating that GSTA4 and TXN2 play key roles in redox homeostasis in RB cells and the susceptibility to HDAC inhibitor treatment upon UHRF1 depletion. In human primary RB, GSTA4 and TXN2 proteins were found to be mostly elevated along with high UHRF1 expression. In addition to augmentation of apoptosis in UHRF1-depleted RB cells, we also show that UHRF1 downmodulation derepresses the expression of photoreceptor-specific genes in RB cells in cooperation with a HDAC inhibitor MS-275 and promotes neuron-like differentiation. However, further investigation revealed that the enhanced growth-inhibitory effects of MS-275 in UHRF1-depleted cells were still mainly due to robust apoptosis induction rather than differentiation-mediated growth arrest. Consistent with our findings, UHRF1 depletion in RB cells increased the therapeutic efficacy of MS-275 in murine orthotopic xenografts. These results provide a novel basis for potential benefits of UHRF1 targeting for RB treatment.

Clinicopathological Findings of Retinoblastoma: A 10-Year Experience from a Tertiary Hospital in Kampala, Uganda

Background

Retinoblastoma (RB) is one of the most common cancers occurring in young children in sub-Saharan Africa. The incidence rate reported in the literature is 9,000 new cases per year, which corresponds to 1 in 15,000 births. This study aimed at analyzing the clinicopathological findings in children with RB in Uganda.

Purpose

The purpose of this study was to describe and analyze the clinicopathological findings in the patients with RB.

Design

This was a cross-sectional analytical study involving 234 eyeball surgical specimens from 214 patients with RB diagnosed between January 2006 and December 2015.

Results

The mean age of the patients was 27.8 months (SD = 21.413, range: 1–132 months). More than half of the cases, 50.9%, presented with leucokoria. Invasion of choroid, sclera, anterior chamber, and optic nerve was found in 26.5% (n = 58), 51.2% (n = 88), 26.2% (n = 45), and 29.2% (n = 49), respectively. Twenty-six percent (n = 56) of the cases with intraocular tumour were at stage I and all patients with metastasis 4.7% (n = 11) had stage IV. The correlation between postlaminar optic nerve invasion and massive choroidal invasion was statistically significant (P = 0.002). Also, there was a statistical significance difference between metastasis and postlaminar invasion (P = 0.004).

Conclusion

The majority of children with RB in Uganda present clinically with leucokoria, and their parents or guardians seek medical intervention at a later stage. Moreover, there was a noticeably significant lag period for the patients to begin treatment after the diagnosis was done.

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.

Update on pathology of retinoblastoma

Retinoblastoma is caused by mutational inactivation of both alleles of the RB1 gene, which maps to chromosome 13q14 and encodes retinoblastoma protein that acts as a tumor suppressor. Histopathological high-risk features of retinoblastoma are predictive of metastasis or local recurrence. The focus of this update is to emphasize the recent advances in pathology, various molecular key pathways and genome wide approaches for newer potential therapeutic future targets associated with retinoblastoma tumor biology. This review article highlights the new biomarkers expressed by the retinoblastoma tumor for the better survival of patients.

The predictive value of magnetic resonance imaging of retinoblastoma for the likelihood of high-risk pathologic features

PURPOSE:

To evaluate the predictive value of magnetic resonance imaging in retinoblastoma for the likelihood of high-risk pathologic features.

METHODS:

A retrospective study of 64 eyes enucleated from 60 retinoblastoma patients. Contrast-enhanced magnetic resonance imaging was performed before enucleation. Main outcome measures included demographics, laterality, accuracy, sensitivity, and specificity of magnetic resonance imaging in detecting high-risk pathologic features.

RESULTS:

Optic nerve invasion and choroidal invasion were seen microscopically in 34 (53%) and 28 (44%) eyes, respectively, while they were detected in magnetic resonance imaging in 22 (34%) and 15 (23%) eyes, respectively. The accuracy of magnetic resonance imaging in detecting prelaminar invasion was 77% (sensitivity 89%, specificity 98%), 56% for laminar invasion (sensitivity 27%, specificity 94%), 84% for postlaminar invasion (sensitivity 42%, specificity 98%), and 100% for optic cut edge invasion (sensitivity100%, specificity 100%). The accuracy of magnetic resonance imaging in detecting focal choroidal invasion was 48% (sensitivity 33%, specificity 97%), and 84% for massive choroidal invasion (sensitivity 53%, specificity 98%), and the accuracy in detecting extrascleral extension was 96% (sensitivity 67%, specificity 98%).

CONCLUSIONS AND RELEVANCE:

Magnetic resonance imaging should not be the only method to stratify patients at high risk from those who are not, eventhough it can predict with high accuracy extensive postlaminar optic nerve invasion, massive choroidal invasion, and extrascleral tumor extension.

9.4T and 17.6T MRI of Retinoblastoma: Ex Vivo evaluation of microstructural anatomy and disease extent compared with histopathology

BACKGROUND

Retinoblastoma is the most common intraocular tumor in childhood with a good prognosis in terms of mortality, but detailed information about tumor morphology and disease extent in retinoblastoma is important for treatment decision making.

PURPOSE

To demonstrate ultrahigh-field MRI tumor morphology and tumor extent in retinoblastoma correlating with in and ex vivo images with histopathology.

STUDY TYPE

Prospective case series.

POPULATION

Six retinoblastoma patients (median age 5.5 months, range 2-14) were prospectively included in this study. Median time between diagnosis and enucleation was 8 days (range 7-19).

FIELD STRENGTH/SEQUENCE

In vivo pre-enucleation at 1.5T MRI with a circular surface coil. Ex vivo imaging (FLASH T₁ -weighted and RARE T₂ -weighted) was performed at field strengths of 9.4T and 17.6T.

ASSESSMENT

After ex vivo imaging, the eyes were histopathologically analyzed and morphologically matched with MRI findings by three authors (two with respectively 14 and 4 years of experience in ocular MRI and one with 16 years of experience in ophthalmopathology).

RESULTS

Small submillimeter morphological aspects of intraocular retinoblastoma were successfully depicted with higher-resolution MRI and matched with histopathology images. With ex vivo MRI a small subretinal tumor seed (300 μm) adjacent to the choroid was morphologically matched with histopathology. Also, a characteristic geographical pattern of vital tumor tissue (400 μm) surrounding a central vessel interspersed with necrotic areas correlated with histopathology images. Tumor invasion into the optic nerve showed a higher signal intensity on T₁ -weighted higher-resolution MRI.

DATA CONCLUSION

Higher-resolution MRI allows for small morphological aspects of intraocular retinoblastoma and extraocular disease extent not visible on currently used clinical in vivo MRI to be depicted.

LEVEL OF EVIDENCE

4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1487-1497.

Evaluation of high-risk features of primary enucleation of patients with retinoblastoma in a tertiary center of a developing country in the era of intra-arterial chemotherapy

PURPOSE

To evaluate the frequency of high-risk histopathologic factors in Turkish children enucleated for retinoblastoma and to analyze the association between growth pattern, rosetta formation, tumor thickness, presence of necrosis, calcification, neovascularization, rate of mitosis, and high-risk histopathologic factors.

METHODS

Pathology reports of 59 eyes who had received enucleation for retinoblastoma were reviewed retrospectively. The histopathologic data included presence of choroidal invasion, optic nerve invasion, scleral extension, tumor thickness, presence of necrosis, calcification, neovascularization, rosetta formation and lymphocyte infiltration, rate of mitosis, and growth pattern.

RESULTS

This study included 59 eyes from 30 (50.8%) male and 29 (49.2%) female patients. The mean age was 22.87 ± 18.99 months. There were 30 (50.8%) eyes with choroidal invasion, 30 (50.8%) eyes with optic nerve invasion, and 5 (8.5%) eyes with scleral invasion. Endophytic growth pattern was seen in 27 (45.8%) eyes, exophytic growth pattern was seen in 2 (3.4%) eyes, and combined growth pattern was seen in 30 (50.8%) eyes. Exophytic growth pattern was found statistically related to choroidal invasion (p = 0.00). Although tumor with greater thickness tended to have more choroidal invasion (p = 0.02), there was no relation between tumor thickness and optic nerve invasion (p = 0.09).

CONCLUSIONS

Incidences of choroidal and optic nerve invasion showed similarity with other developing countries. Because of higher incidence of high-risk factors, intra-arterial chemotherapy with its targeted effect should be preferred carefully.

OPTIC NERVE INFILTRATION BY RETINOBLASTOMA: Predictive Clinical Features and Outcome

PURPOSE

To identify the clinical features predictive of any optic nerve infiltration and postlaminar optic nerve infiltration by retinoblastoma on histopathology and to report the outcome (metastasis and death) in these patients.

METHODS

Retrospective study.

RESULTS

Of the 403 patients who underwent primary enucleation for retinoblastoma, 196 patients had optic nerve tumor infiltration (Group 1) and 207 patients had no evidence of optic nerve tumor infiltration (Group 2). Group 1 included patients with prelaminar (n = 47; 24%), laminar (n = 74; 38%), and postlaminar tumor infiltration with or without involving optic nerve transection (n = 74; 38%). Comparing Group 1 and Group 2, the patients in Group 1 had prolonged duration of symptoms (>6 months) (16% vs. 8%; P = 0.02) and were associated with no vision at presentation (23% vs. 10%; P = 0.01), higher rates of secondary glaucoma (42% vs. 12%; P < 0.0001), iris neovascularization (39% vs. 23%; P < 0.001), and larger tumors (mean tumor thickness, 12.8 mm vs. 12 mm; P = 0.0001). There was a higher prevalence of metastasis in Group 1 than in Group 2 (4% vs. 0%; P = 0.006). On multivariate analysis, clinical features predictive of any optic nerve tumor infiltration secondary glaucoma (hazard ratio = 5.38; P < 0.001) and those predictive of postlaminar optic nerve tumor infiltration included iris neovascularization (hazard ratio = 2.66; P = 0.001) and secondary glaucoma (hazard ratio = 3.13; P < 0.001).

CONCLUSION

In this study, clinical features predictive of any optic nerve tumor infiltration included secondary glaucoma and those predictive of postlaminar optic nerve tumor infiltration included iris neovascularization and secondary glaucoma. Despite adjuvant treatment in those with postlaminar optic nerve tumor infiltration, metastasis occurred in 8% of patients.

Choroidal Infiltration by Retinoblastoma: Predictive Clinical Features and Outcome

PURPOSE

To identify the clinical features predictive of choroidal infiltration by retinoblastoma on histopathology and to report the outcome in these patients.

METHODS

Retrospective study.

RESULTS

Of the 403 patients who underwent primary enucleation for retinoblastoma, 113 patients had choroidal tumor infiltration and 290 patients had no choroidal tumor infiltration. There was a higher incidence of metastasis and related death in the choroidal tumor infiltration group compared to the no choroidal tumor infiltration group (4% vs 1%; P = .02). On multivariate analysis, the clinical features predictive of histopathologic massive choroidal infiltration included prolonged duration of symptoms for more than 6 months (hazard ratio [HR] = 3.04; P = .001) and secondary glaucoma (HR = 2.24; P = .005).

CONCLUSIONS

In this study, the patients with retinoblastoma with prolonged duration of symptoms (> 6 months) had a three-fold greater risk and those with secondary glaucoma at presentation had a two-fold greater risk of massive choroidal tumor infiltration. [J Pediatr Ophthalmol Strabismus. 2016;53(6):349-356.].

A Study of Gene Expression of Survivin, its Antiapoptotic Variants, and Targeting Survivin In Vitro for Therapy in Retinoblastoma

Apoptosis is a natural process regulated by apoptotic and antiapoptotic molecules. We investigated mRNA expression of survivin and its splice variants, along with B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax), in a cohort of 20 retinoblastoma (RB) tumors by real-time polymerase chain reaction. We hypothesized a correlation between the Bcl-2/Bax and survivin splice variants and also that expression of these would be associated with clinicopathologic features of tumors. The Bcl-2 expression was significantly higher (P<0.001) in RB, and Bcl-2/Bax ratio was remarkably higher in poorly differentiated tumors. A statistically significant higher expression of Survivin-WT (wild type) compared with its variant Survivin-2β (P<0.05) was observed. Bcl-2 did not exhibit positive correlation with any of the survivin variants except Survivin-2β, whereas Bax exhibited significant (P<0.05) correlation with the variants. Thus, it could be suggested that a superior player out of a likely interaction between the variants and Bcl-2/Bax uses its activity for the progression of RB. Silencing of Survivin-WT in the Y79 cell line was studied by siRNA technology and cell-permeable dominant negative survivin (SurR9-C84A). siRNA showed higher proapoptotic effects and increased caspase 3/7 activity in Y79 cells. Effective internalization of SurR9-C84A in Y79 cells induced cytotoxic effects. Thus, the current study confirms survivin as a promising target for therapy.

Ocular topotecan pharmacokinetics following topical administration to rabbits for diffused anterior retinoblastoma

OBJECTIVES

We characterized and compared the in-vivo absorption of topotecan into the aqueous humor after instillation of aqueous and ointment formulations.

METHODS

A lanolin/petrolatum ointment was used. New Zealand rabbits were instilled with topotecan solution (6 μg, group A), a single 10 μg dose of topotecan ointment (group B) or with five 10 μg doses of topotecan ointment (group C). Aqueous humor samples were collected at different times. Corneal samples were collected only for group A. Topotecan was quantified using HPLC, and pharmacokinetic parameters were calculated. Acute corneal epithelial toxicity was assessed after multiple instillations of topotecan ointment.

KEY FINDINGS

Total topotecan maximum aqueous humor concentration (C_max ) was 16.1, 69.9 and 287 ng/ml in group A, B and C, respectively. A single dose of topotecan ointment increased threefold and sevenfold the aqueous humor C_max , and exposure compared to the aqueous formulation. Aqueous humor concentrations from group C eyes were substantially above the cytotoxic concentration for retinoblastoma cells. No corneal toxicity was evident after ointment instillation.

CONCLUSIONS

Topotecan penetrated into the aqueous humor of the rabbit eye after multiple doses of an ointment in concentrations pharmacologically active against retinoblastoma cells without eliciting acute toxicity. Topotecan ointment may translate to the clinical treatment of anterior segment disseminated retinoblastoma.

PREDICTIVE VALUE OF TNM CLASSIFICATION, INTERNATIONAL CLASSIFICATION, AND REESE-ELLSWORTH STAGING OF RETINOBLASTOMA FOR THE LIKELIHOOD OF HIGH-RISK PATHOLOGIC FEATURES

PURPOSE

To evaluate the predictive value of the seventh edition American Joint Committee on Cancer (AJCC/UICC) TNM classification, the International Classification of Retinoblastoma (ICRB), and Reese-Ellsworth staging for retinoblastoma for the likelihood of high-risk pathologic features.

METHODS

A retrospective study of 50 primarily enucleated eyes from 49 retinoblastoma patients. Main outcome measures included demographics, TNM stage, ICRB group, Reese-Ellsworth stage, choroid, optic nerve, and anterior chamber invasion.

RESULTS

The median age at enucleation was 30 months. High-risk pathologic features mandating adjuvant chemotherapy were seen in 5 of T2 eyes (22%), in 15 of T3 eyes (56%) (P = 0.021), in 1 of ICRB Group C eyes (13%), 8 of Group D eyes (33%), and 11 of Group E eyes (61%) (P = 0.035). High-risk pathologic features were 4.61 and 3.68 times more likely to be diagnosed at a more advanced T stage and ICRB group consecutively, whereas 0.133 time less likely to be diagnosed at a more advanced Reese-Ellsworth stage. At median follow-up of 40 months, no single case had metastasis or was dead.

CONCLUSION

The higher tumor clinical TNM stage and the more advanced ICRB group at presentation are associated with higher frequency of high-risk pathologic features and may predict which patients should receive adjuvant chemotherapy.

Retinoblastoma in Mongolia: Clinical characteristics and survival from 1987 to 2014

Background/Purpose:

This study aims to describe the clinical characteristics and treatment outcome of retinoblastoma in Mongolian children.

Methods:

Data of all children diagnosed with retinoblastoma at the National Center for Maternal and Child Health of Mongolia from 1987 to January 2014 were reviewed retrospectively. The ICRB classification was used. Survival characteristics of the cohort were analyzed.

Results:

Retinoblastoma was diagnosed in 79 eyes of 64 cases during the study period. Median age of diagnosis was 24.5 ± 15.8 months. There were no differences in sex ratio, and 15 cases (23%) were bilateral. Forty-three (67%) patients were from rural areas. The more frequent clinical presentations were leukocoria in 50 (78%) patients, strabismus in 24 (38%) patients, and glaucoma in 21 (33%) patients. Sixty-one (95%) patients were diagnosed with Classification D or worse when presented to us. Due to late diagnosis in the majority of cases, unilateral and bilateral enucleations were performed in 48 (61%) eyes and 24 (30%) eyes, respectively; exenteration was done in three (4%) eyes. Fifty-two (81%) patients received chemotherapy and 13 (8.3%) patients underwent external beam radiation after enucleation. At the time of last follow-up, 52 (81%) patients were alive, five (8%) patients were dead, and seven (11%) patients had lost to follow-up or unknown vital status. The mean follow-up period was 121.5 months (range, 12–360 months). In five cases with immunohistochemistry analysis in the eye specimen, neuron-specific enolase-, Ki-67 protein-, and B-cell lymphoma 2-positive cells were found in all five (100%) cases and Rb protein was detected in three (60%) cases.

Conclusion:

Retinoblastoma in Mongolia is frequently diagnosed at late stages and has a poor outcome. These data show the importance of early pediatric eye examinations and better treatment of retino-blastoma in children younger than 3 years in Mongolia.

Macroscopic techniques for ophthalmic tumor specimens

This article explores the range of tumor specimens that may be submitted to ophthalmic pathology. The handling of complex enucleation and exenteration is described along with smaller eyelid, conjunctival and corneal specimens. The importance of a good understanding of the unique anatomy of the ocular region and detailed clinical information is emphasized as this results in the taking of appropriate blocks for histology and consequently clinically helpful reports. Recommendations for handling specimens where further tissue is required for molecular studies is discussed.

Retinoblastoma in Chinese Children Aged Five to Fourteen Years

OBJECTIVE

To assess the characteristics of retinoblastomas enucleated from Chinese children aged 5-14 years.

METHODS

This retrospective hospital-based study included all eyes with retinoblastomas consecutively enucleated in the Beijing Tongren Hospital between August 2003 and July 2013.

RESULTS

Out of 1,205 patients, 47 (3.9%) were 5 years or older. All tumors in this age group occurred unilaterally, the patients had a negative family history, and the tumors were detected at an age of 6.9 ± 1.8 years (range: 5-14). The main clinical features at the time of examining the as yet untreated children aged 5-7 years (n = 30) or >7-14 years (n = 10) were leukocoria, strabismus, pseudohypopyon, hypertension, vitreous seeds ('snowballs'), and calcifications. In 12 patients (26%), the retinoblastoma had not initially been diagnosed as a tumor. Histopathology revealed tumor invasion into nonretinal tissue in 19 eyes (40%). Therapy included enucleation only (n = 22; 47%), adjuvant systemic chemotherapy (n = 24; 51%), and additional orbital exenteration (n = 1). After a mean follow-up of 3.0 ± 2.1 years (range: 0.2-9.8), which was done for 40 children, none of these children showed a tumor recurrence.

CONCLUSIONS

Of the children undergoing enucleation for retinoblastoma in Beijing, 3.9% were aged 5 years or more. As in Western countries, the tumor occurrence was unilateral, their family history was negative, and the survival rate was relatively high in these children. In 1 out of 4 children, the tumor had initially been misdiagnosed due to a masquerade syndrome. Retinoblastoma should be considered in the differential diagnosis of any unclear intraocular situation in children.

p16(INK4a) expression in retinoblastoma: a marker of differentiation grade

Background

The tumor suppressor protein p16^INK4a has been extensively studied in many tumors with very different results, ranging from its loss to its clear overexpression, which may be associated with degree of tumor differentiation and prognosis. However, its expression remains unclear in human retinoblastoma (RB), a common malignant tumor of retina in childhood. The aim of this study was to explore the expression pattern of p16^INK4a in RB, and the correlation between p16^INK4a expression and histopathological features of RB.

Methods

Sixty-five cases of RB were retrospectively analyzed. Paraffin-embedded blocks were retrieved from the archives of ocular pathology department at Zhongshan Ophthalmic Center of Sun Yat-sen University, China. Serial sections were cut and subjected to hematoxylin and eosin staining. Immunohistochemical staining was further done with antibodies p16^INK4a, CRX and Ki67. The correlation of p16 ^INK4a expression with CRX and Ki67 and clinicopathological features of RB were analyzed.

Results

RB tumor histologically consists of various differentiation components including undifferentiated (UD) cells, Homer-Wright rosettes (HWR) or Flexner-Winterstein rosettes (FWR) and fleurettes characteristic of photoreceptor differentiation or Retinocytoma (RC). p16^INK4a expression was negative in both fleurette region and the residual retinal tissue adjacent to the tumor, weakly to moderately positive in FWR, strongly positive in both HWR and UD region. However, CRX had the reverse expression patterns in comparison with p16^INK4a. It was strongly positive in photoreceptor cells within the residual retina and fleurettes, but weakly to moderately positive in UD area. Together with Ki67 staining, high p16^INK4a expression was associated with poor histological differentiation of RB tumors, which had higher risk features with the optic nerve invasion and uveal invasion.

Conclusions

p16^INK4a expression increased with the decreasing level of cell differentiation of RBs. RB tumors extensively expressing p16^INK4a tended to have higher risk features with poor prognosis. This study suggested that p16^INK4a would be a valuable molecular marker of RB to distinguish its histological phenotypes and to serve as a predictor of its prognosis.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_180

Anterior segment invasion in retinoblastoma: is it a risk factor for extraocular relapse?

We report a retrospective review of patients with retinoblastoma and anterior segment invasion (ASI) as risk factors for extraocular relapse. Only those with ASI combined with postlaminar optic nerve invasion and/or scleral invasion received adjuvant chemotherapy and those with tumor at the resection margin received orbital radiotherapy. Those with only uveal invasion did not receive adjuvant therapy. Of 479 evaluable patients, 67 patients had pathologically confirmed ASI, including 52 with anterior chamber invasion and 47 with iris or ciliary body invasion. ASI occurred with other pathology risk factors (25 had concomitant posterior uveal invasion, 36 had postlaminar optic nerve invasion, 11 with cut-end invasion, and 25 with scleral invasion). The 5-year disease-free survival (pDFS) was 0.9 (95% CI, 0.8-0.95) for children with ASI with no significant differences among children with other pathology risk factors with and without ASI. ASI was not significantly associated with extraocular relapse in multivariate analysis. There were no significant differences in pDFS for patients with anterior chamber invasion and those with iris-ciliary body invasion (pDFS 0.89 [95% CI, 0.65-0.96] vs. 0.93 [95% CI, 0.61-0.98]). To conclude, ASI was seen with other pathology risk factors and it did not add a significant risk for extraocular relapse.

Hypoxic tumor microenvironment in advanced retinoblastoma

PURPOSE

Retinoblastoma (RB) is a malignant tumor of infancy and childhood. Unfavorable therapeutic response is still a quest in many tumors, including retinoblastoma. Hypoxic tumor microenvironment is one of the factors that determine the therapeutic response in many tumors. The purpose of this study was to determine the presence of hypoxia and its related proteins; Hypoxia inducible factor-1α (HIF-1α), Carbonic anhydrase IX (CA IX) and survivin in RB and their association with clinicopathological features.

MATERIALS AND METHODS

We evaluated the expression of HIF-1α and survivin by immunohistochemistry in 42 archival retinoblastoma tumors and CA IX; a hypoxia marker in 33 tumors in the same cohort. The expression was correlated with tumor groups based on invasion, differentiation and IIRC.

RESULTS

Expression of HIF-1α, survivin and CA IX was observed in 83% (35/42), 86% (36/42), and 93% (31/33) of tumors respectively. We observed no significance between HIF-1α and CA IX expression in tumors with invasion, differentiation and in IIRC tumor groups. An increased survivin expression was observed in group E tumors than in group D tumors (P = 0.044). A significant association was observed between HIF-1α and survivin in differentiated (r = -0.582; P = < 0.01) and undifferentiated tumors groups (r = 0.513; P = <0.012). A similar significant association was observed between HIF-1α and CA IX in tumors with high immunoreactivity for HIF-1α (r = 0.833; P = <0.01).

CONCLUSION

Based on these observations, we propose that HIF-1α pathway is deregulated in RB. The role of drug resistance and the potential of targeting HIF-1α, CA IX, and survivin in RB should further examined.

Extraocular retinoblastoma in Indian children: clinical, imaging and histopathological features

AIM

TO STUDY EYES WITH EXTRAOCULAR DISSEMINATION (EORB), WITH THE FOLLOWING AIMS: first to establish the mean lag period and to understand various reasons for delayed presentation, second to study their imaging profiles and third to analyze histopathological features of eyes enucleated after neoadjuvant chemotherapy.

METHODS

Prospective study of clinical and imaging features of EORBs (stage III and IV International Retinoblastoma Staging System) presenting to a tertiary eye care centre. Histopathological features of eyes enucleated after receiving neoadjuvant chemotherapy were analyzed. A pictorial illustration of the varied imaging profile of EORB was also presented.

RESULTS

Over a period of one year, 97 eyes were diagnosed with retinoblastoma; 32 children (36 eyes) (37.1%) had EORB. Mean age 3.6±1.9 years, 71.9% males, 71.9% unilateral, 3.1% with positive family history and 40.6% with metastasis. On imaging, there was extrascleral involvement in 22.2%, involvement of orbital part of optic nerve in 33.3%, involvement of central nervous system in 27.8% and orbital wall involvement in 2.9% eyes. On histopathological analysis of eyes enucleated after neoadjuvant chemotherapy, 25.0% had no residual viable tumour tissue and rest all tumours were poorly differentiated.

CONCLUSION

There are very few human malignancies where definitive treatment is started without any confirmed histopathological diagnosis and imaging plays an important role in diagnosis and appropriate staging of the disease. Chemotherapy has a variable effect on EORB, 75.0% of eyes with EORB had residual viable tumour tissue when enucleated after receiving neoadjuvant chemotherapy.

Differentiation in retinoblastoma and histopathological risk factors in Mexico

PURPOSE

To describe the relationship between retinoblastoma differentiation, histopathological risk factors, age at enucleation, laterality, and genetic type (hereditary or sporadic) in a series of enucleated eyes in a referral hospital. The criteria used in other studies to classify retinoblastoma differentiation are discussed.

METHODS

The authors retrospectively studied histopathological preparations of eyes with retinoblastoma treated with primary enucleation. Tumors were classified as well differentiated, undifferentiated, and moderately differentiated. Patient age at enucleation, laterality of disease, genetic form (hereditary or sporadic), and presence of histopathological risk factors (massive choroidal infiltration, postlaminar optic nerve invasion, tumor in optic nerve cut, scleral invasion, and involvement of orbital soft tissues) were analyzed. The chi-square test was used for categorical variables and analysis of variance for test mean differences.

RESULTS

Histopathological risk factors were present in 23 (36%) of 63 eyes. Moderately differentiated tumors occurred at advanced ages and were more frequently associated with histopathological risk factors.

CONCLUSIONS

A consensus is needed to establish the histopathological criteria of retinoblastoma differentiation. The value of rosettes as a marker of cell differentiation should be reviewed.[J Pediatr Ophthalmol Strabismus 2013;50(3):174-177.].