Targeted retinoblastoma management: when to use intravenous, intra-arterial, periocular, and intravitreal chemotherapy

Hematological Second Primary Malignancy in Pediatric Retinoblastoma: A Case Report and Systematic Review

PURPOSE

The impact of heredity and treatment modalities on the development of hematologic second primary malignancies (SPMs) is unclear. This study primarily reviewed the literature on patients with hematologic SPMs after retinoblastoma.

METHODS

The PubMed and Web of Science databases were searched to identify all cases of hematologic SPMs after retinoblastoma through December 2023 (International prospective register of systematic reviews CRD42023488273).

RESULTS

Sixty-one patients from 35 independent publications and our case were included. Within the cohort, 15 patients (51.7%) were male, and 14 patients (48.3%) were female. Of the 43 cases with known heritability status, 27 (62.8%) were classified as heritable and 16 (37.2%) as nonheritable. The median age at diagnosis was 18 months (IQR: 7.00-36.00). The geographic distribution of patients was diverse, with North America accounting for 35.0% (21/60) of cases. The following treatment strategies were used: 11.9% (5/42) of patients received neither chemotherapy nor radiotherapy, 33.3% (14/42) received chemotherapy alone, 11.9% (5/42) received radiotherapy alone, and 42.9% (18/42) received a combination of chemotherapy and radiotherapy. The median delay between retinoblastoma diagnosis and SPM diagnosis was 40 months (IQR: 22.00-85.00). Among the 61 cases, acute myeloid leukemia accounted for 44.3% (27/61), followed by acute lymphoblastic leukemia in 21.3% (13/61), Hodgkin's lymphoma in 11.5% (7/61), non-Hodgkin's lymphoma in 9.8% (6/61), chronic myeloid leukemia in 3.3% (2/61), and acute natural killer cell leukemia in 1.6% (1/61).

CONCLUSIONS

Vigilant systemic surveillance for hematologic SPMs in retinoblastoma survivors, especially those treated with systemic chemotherapy and those with hereditary conditions, is warranted to improve management strategies and patient outcomes.

Safety of intravitreal chemotherapy in the management of retinoblastoma: A systematic review of the literature

Intravitreal chemotherapy is used as a salvage therapy for retinoblastoma with persistent or recurrent vitreous seeding after primary treatment. To assess the safety of this technique, we conducted a systematic review of all studies reporting ocular toxicity data. Forty-eight trials involving 2751 eyes were included. The most common complications were cataract, retinal toxicity, and vitreous hemorrhage. However, severe and permanent adverse events were limited, while the risk of extraocular dissemination, a significant concern, was practically eliminated through preventive techniques. Globe salvage rates ranged from 29 % to 100 %. In conclusion, intravitreal chemotherapy seems to improve prognosis of eyes with advanced disease, with an acceptable safety profile. Nevertheless, most relevant studies are retrospective, and no randomized trials have been performed. Recognizing the challenges regarding the conduct of randomized studies for such a rare pediatric cancer, we believe that multicenter trials through international collaborations can significantly enhance the available information.

Personalized treatment approaches in intraocular cancer

Background

Intraocular malignant tumors represent a severe disease that threatens vision as well as life. To better extend the life of the patient, preserve visual function, and maintain ocular aesthetics, selecting the appropriate timing and methods of treatment becomes crucial.

Main text

With the continuous advancement of medical technology, the techniques and methods for treating intraocular malignant tumors are constantly evolving. While surgery was once considered the optimal method to prolong patient survival and prevent local recurrence, the discovery and application of various treatments such as radiotherapy, laser therapy, chemotherapy, cryotherapy, and monoclonal antibodies have led to a greater diversity of treatment options. This diversity offers more possibilities to develop personalized treatment plans, and thereby maximize patient benefit. This article reviews the various treatment methods for intraocular malignant tumors, including indications for treatment, outcomes, and potential complications.

Conclusions

Differentiating small intraocular malignant tumors from pigmented lesions is challenging, and ongoing monitoring with regular follow-up is required. Small to medium-sized tumors can be treated with radiotherapy combined with transpupillary thermotherapy. Depending on the tumor's distance from the optic disc, surgery with partial resection may be considered for distant tumors, while proximal tumors may require complete enucleation. Systemic chemotherapy has been widely applied to patients with retinal tumors, lymphomas, and intraocular metastatic cancers, but has limited efficacy in patients with choroidal melanoma. Antagonists of Vascular Endothelial Growth Factor (Anti-VEGF) drugs can improve patient vision and quality of life, while the efficacy of immunotherapy and molecular targeted therapy is still under research.

Retinoblastoma: An update on genetic origin, classification, conventional to next-generation treatment strategies

The most prevalent paediatric vision-threatening medical condition, retinoblastoma (RB), has been a global concern for a long time. Several conventional therapies, such as systemic chemotherapy and focal therapy, have been used for curative purposes; however, the search for tumour eradication with the least impact on surrounding tissues is still ongoing. This review focuses on the genetic origin, classification, conventional treatment modalities, and their combination with nano-scale delivery systems for active tumour targeting. In addition, the review also delves into ongoing clinical trials and patents, as well as emerging therapies such as gene therapy and immunotherapy for the treatment of RB. Understanding the role of genetics in the development of RB has refined its treatment strategy according to the genetic type. New approaches such as nanostructured drug delivery systems, galenic preparations, nutlin-3a, histone deacetylase inhibitors, N-MYC inhibitors, pentoxifylline, immunotherapy, gene therapy, etc. discussed in this review, have the potential to circumvent the limitations of conventional therapies and improve treatment outcomes for RB. In summary, this review highlights the importance and need for novel approaches as alternative therapies that would ultimately displace the shortcomings associated with conventional therapies and reduce the enucleation rate, thereby preserving global vision in the affected paediatric population.

Retinoblastoma - A comprehensive review, update and recent advances

Retinoblastoma is the most common pediatric ocular malignancy. It is triggered by a biallelic mutation in the RB1 gene or MYCN oncogene amplification. Retinoblastomas can be unilateral (60%-70%) or bilateral (30%-40%); bilateral tumors are always heritable and present at an earlier age as compared to unilateral ones (18-24 months vs. 36 months in India). High prevalence rates, delayed presentation, and inaccessibility to healthcare lead to worse outcomes in developing countries. The past few decades have seen a paradigm change in the treatment of retinoblastomas, shifting from enucleation and external beam radiotherapy to less aggressive modalities for eye salvage. Multimodality treatment is now the standard of care and includes intraarterial or intravenous chemotherapy along with focal consolidation therapies such as transpupillary thermotherapy, cryotherapy, and laser photocoagulation. Intravitreal and intracameral chemotherapy can help in controlling intraocular seeds. Advanced extraocular or metastatic tumors still have a poor prognosis. Genetic testing, counseling, and screening of at-risk family members must be incorporated as essential parts of management. A better understanding of the genetics and molecular basis of retinoblastoma has opened up the path for potential targeted therapy in the future. Novel recent advances such as liquid biopsy, prenatal diagnosis, prognostic biomarkers, tylectomy, and chemoplaque point to promising future directions.

USP14 increases the sensitivity of retinoblastoma to cisplatin by mediating the ferroptosis

The aim of this study is to explore the function of USP14 on the sensitivity of retinoblastoma (RB) to cisplatin (DDP) and the underlying mechanism. USP14 was knockdown in Y79 cells by transfecting three siRNAs (si-USP14-1, si-USP14-2, and si-USP14-3), with si-USP14 NC as the negative control. si-USP14-3 was selected by results of Western blotting. The CCK-8 assay was used to detect the IC50 of Y79 cells and the growth curve. The cell cycle, cell apoptosis, and ROS level were measured by flow cytometry. The expression level of P-GP, ERCC1, survivin, GPX4, FTH1, ACSL4, NOX1, COX2, and FASN was determined by the Western blotting assay. CO-IP assay was utilized to evaluate the interaction between USP14 and FASN. The IC50 of DDP in Y79 cells and Y79/DDP cells was 7.83 µM and 24.67 µM, respectively. Compared to control and si-USP14 NC groups, increased apoptotic rate and ROS level, and arrested cell cycle in S phase were observed in USP14-knockdown Y79 cells. Compared to control and si-USP14 NC groups, increased apoptotic rate and arrested cell cycle in G0/G1 phase were observed in USP14-knockdown Y79/DDP cells. Compared to control, increased ROS level was observed in USP14-knockdown Y79/DDP cells. Compared to the si-USP14 NC groups, extremely downregulated P-GP, ERCC1, survivin, GPX4, FTH1, NOX1, COX2, and FASN were observed in USP14-knockdown Y79 cells or Y79/DDP cells, accompanied by the elevated expression of ACSL4. The interaction between USP14 and FASN was identified according to the result of CO-IP assay. By silencing USP14 in Y79 and Y79/DDP cells, levels of resistance-related proteins (P-GP, ERCC1, and survivin), ferroptosis-related proteins (FTH1 and GPX4), and lipid metabolism-related proteins (NOX1, COX2, and FASN) were dramatically reduced, accompanied by enhanced ROS level, increased apoptosis, and restrained DNA content, indicating that USP14 might suppress the DDP resistance in RB by mediating ferroptosis, which is an important target for treating RB.

MR Imaging of Adverse Effects and Ocular Growth Decline after Selective Intra-Arterial Chemotherapy for Retinoblastoma

This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring the availability of posttreatment MR imaging encompassing T2-weighted and T1-weighted images (pre- and post-intravenous gadolinium administration). Qualitative features and quantitative measurements were independently scored by experienced radiologists, with deep learning segmentation aiding total eye volume assessment. Eyes were categorized into three groups: eyes receiving SIAC (Rb-SIAC), eyes treated with other eye-saving methods (Rb-control), and healthy eyes. The most prevalent adverse effects post-SIAC were inflammatory and vascular features, with therapy-induced contrast enhancement observed in the intraorbital optic nerve segment in 6% of patients. Quantitative analysis revealed significant growth arrest in Rb-SIAC eyes, particularly when treatment commenced ≤ 12 months of age. Optic nerve atrophy was a significant complication in Rb-SIAC eyes. In conclusion, this study highlights the vascular and inflammatory adverse effects observed post-SIAC in retinoblastoma patients and demonstrates a negative impact on eye and optic nerve growth, particularly in children treated ≤ 12 months of age, providing crucial insights for clinical management and future research.

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.

Role of Protein Tyrosine Phosphatase Receptor Type E (PTPRE) in Chemoresistant Retinoblastoma

Protein tyrosine phosphatase receptor type E (PTPRE) is a member of the "classical" protein tyrosine phosphatase subfamily and regulates a variety of cellular processes in a tissue-specific manner by antagonizing the function of protein tyrosine kinases. PTPRE plays a tumorigenic role in different human cancer cells, but its role in retinoblastoma (RB), the most common malignant eye cancer in children, remains to be elucidated. Etoposide-resistant RB cell lines and RB patients display significant higher PTPRE expression levels compared to chemosensitive counterparts and the healthy human retina, respectively. PTPRE promotor methylation analyses revealed that PTPRE expression in RB is not regulated via this mechanism. Lentiviral PTPRE knockdown (KD) induced a significant decrease in growth kinetics, cell viability, and anchorage-independent growth of etoposide-resistant Y79 and WERI RB cells. Caspase-dependent apoptosis rates were significantly increased and a re-sensitization for etoposide could be observed after PTPRE depletion. In vivo chicken chorioallantoic membrane (CAM) assays revealed decreased tumor formation capacity as well as reduced tumor size and weight following PTPRE KD. Expression levels of miR631 were significantly downregulated in etoposide-resistant RB cells and patients. Transient miR631 overexpression resulted in significantly decreased PTPRE levels and concomitantly decreased proliferation and increased apoptosis levels in etoposide-resistant RB cells. These impacts mirror PTPRE KD effects, indicating a regulation of PTPRE via this miR. Additionally, PTPRE KD led to altered phosphorylation of protein kinase SGK3 and-dependent on the cell line-AKT and ERK1/2, suggesting potential PTPRE downstream signaling pathways. In summary, these results indicate an oncogenic role of PTPRE in chemoresistant retinoblastoma.

Evidence in Focus: The Sparse Landscape of Randomized Trials on Retinoblastoma Treatment

Background

Retinoblastoma, although rare, is one of the most common intraocular malignancies worldwide. Its prognosis has improved significantly in the past few decades, thanks to modern treatments, like systemic, intra-arterial, and intravitreal chemotherapy. However, regarding survival, there are significant differences between high- and low-income countries, eye salvage is still a challenge worldwide, and treatment-related toxicity needs to be carefully and sufficiently managed.

Summary

To appraise the strength of supporting evidence, we performed a systematic review of randomized controlled trials investigating any therapeutic protocol for retinoblastoma. Four trials with 174 participants (188 eyes) were eligible, all pertaining to different intravenous chemotherapy regimens. Vincristine, etoposide, and carboplatin (VEC) appear superior to a 5-drug combination for stage III retinoblastoma. Moreover, etoposide and carboplatin as neoadjuvant chemotherapy followed by thermochemotherapy seem to offer better local control than vincristine and carboplatin. However, increasing carboplatin dose in the VEC protocol failed to improve treatment efficacy.

Key Messages

Retinoblastoma is a success story of modern medicine. However, only intravenous chemotherapy has been studied through randomized trials, while evidence for the most novel retinoblastoma treatments has mainly stemmed from observational studies. International collaborations for multicenter randomized trials could overcome difficulties and increase certainty and precision in the field.

Advanced Interventional Treatments in Retinoblastoma Management: A Comprehensive Review

Retinoblastoma is the most common eye malignancy in children that if left untreated can invade intraocular structures, metastasize, and rarely lead to death. Traditionally treated with systemic chemotherapy, Intra-arterial chemotherapy is gaining popularity as it allows for the direct administration of chemotherapy through the ophthalmic artery, thus reducing systemic side effects. Intra-arterial chemotherapy procedures have evolved, with refinements to reduce risks and radiation exposure. Intra-arterial chemotherapy boasts an impressive technical success rate and one year ocular survival even amongst advanced cases. This review offers a thorough examination of the technique, indications, contraindications, outcomes, and alternative options for Intra-arterial chemotherapy.

Update on chemotherapy modalities for retinoblastoma: Progress and challenges

Retinoblastoma stands as a paradigm of success in treating malignancies among pediatric patients. Over recent decades, the approach to managing retinoblastoma has evolved significantly, transitioning from the preservation of patients' lives to the preservation of eyes and vision while minimizing treatment-related complications. Chemotherapy, administered through diverse routes, has solidified its role as the cornerstone of retinoblastoma treatment. In addition to intravenous chemotherapy (IVC), alternative administration routes, including intraarterial (IAC), intravitreal, intracameral, and periocular delivery, have emerged as promising modalities for retinoblastoma management. Numerous studies have demonstrated outstanding outcomes, achieving nearly 100% salvage rates for eyes classified under groups A-C. However, for advanced intraocular retinoblastoma (groups D and E eyes), IAC appears to offer superior local control rates compared to IVC. Intravitreal injection of chemotherapeutic agents, when administered in a controlled and secure manner, holds promise in averting the need for enucleation and radiotherapy in advanced retinoblastoma cases presenting with vitreous seeds. The optimal chemotherapy strategy remains meticulously tailored based on numerous factors. This review provides a comprehensive update on chemotherapy across various routes, encompassing key considerations, dosages, administration methods, treatment outcomes, and potential complications. Furthermore, it explores emerging potential treatments and outlines future directions aimed at enhancing treatment outcomes.

A Review of Pediatric Ophthalmic Tumors

Tumors of the eye, orbit, and ocular adnexa can arise in the pediatric population. These entities can be both vision- and life-threatening and may be associated with systemic disease. Given their relative rarity, pediatricians must be aware of these conditions and understand what findings warrant immediate referral to an ophthalmologist for initiation of further testing. We aimed to review these conditions and highlight clinical features to promote awareness and expedite diagnosis. Tumors are subdivided into the following categories for review: anterior tumors of the eyelid and ocular surface, orbital tumors, and intraocular tumors.

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.

Advancements in Retinoblastoma Treatment: Unraveling the Potential of Intravitreal Chemotherapy

Retinoblastoma necessitates urgent attention due to its potential fatality if untreated. Multiple treatment options are available and should be employed according to size, location, and the extent of dissemination. This review emphasizes the need for increased awareness, advanced diagnostic tools, and innovative treatment approaches, especially intravitreal chemotherapy (IVitC) to address the diverse manifestations and aggressive nature of retinoblastoma. Timely diagnosis and commitment to treatment are pivotal, as delays and reluctance to undergo enucleation contribute to unfavorable outcomes. The evolving treatment landscape, spanning from traditional interventions to modern targeted therapies such as intravitreal melphalan, holds promise for improved outcomes. While the intravitreal approach presents challenges, ongoing research aims to establish its definitive role in retinoblastoma treatment. In the treatment of retinoblastoma, IVitC raises considerations about side effects. The risk of tumor spread beyond the eye is rare, emphasising the potential of IVitC in carefully selected cases. Intravitreal injections exhibit fewer local adverse effects compared to intra-arterial chemotherapy, with careful measures reducing significant ocular complications. The evaluation of ocular toxicity, particularly with melphalan, underscores the importance of a nuanced approach to achieve the right balance between therapeutic efficacy and ocular safety. This comprehensive analysis of studies on IVitC and its ocular and systemic complications provides valuable insights for enhanced patient care. The review concludes with a focus on balancing safety and efficacy in local chemotherapeutic drugs, highlighting the need for thoughtful measures and continued research to optimise treatment modalities globally.

Likelihood of germline mutation with solitary retinoblastoma based on tumour location at presentation

BACKGROUND/AIMS

To evaluate the likelihood of germline mutation in patients presenting with solitary retinoblastoma based on tumour location at first examination.

METHODS

Retrospective analysis of solitary unilateral retinoblastoma for likelihood of germline mutation (family history of retinoblastoma and/or genetic testing indicating germline RB1 mutation and/or development of additional new or bilateral tumours) based on tumur location at presentation (macular vs extramacular).

RESULTS

Of 480 consecutive patients with solitary retinoblastoma, 85 were in the macula (18%) and 395 were extramacular (82%). By comparison (macular vs extramacular tumours), macular tumours had smaller basal diameter (12.7 mm vs 18.9 mm, p<0.001) and smaller tumour thickness (6.1 mm vs 10.7 mm, p<0.001). Patients with macular tumours demonstrated greater likelihood for germline mutation (23% vs 12%, OR=2.18, p=0.011), specifically based on family history of retinoblastoma (13% vs 2%, OR=4.64, p=0.004), genetic testing showing germline RB1 mutation (27% vs 15%, OR=2.04 (95% CI 1.04 to 4.01), p=0.039), development of new tumours (13% vs 3%, OR=5.16 (95% CI 2.06 to 12.87), p=0.001) and/or development of bilateral disease (9% vs 2%, OR=4.98 (95% CI 1.70 to 14.65), p=0.004).

CONCLUSIONS

Among patients with solitary unilateral retinoblastoma, those presenting with macular tumour (compared with extramacular tumour) show 2.18 times greater likelihood for germline mutation and an even higher likelihood of development of subsequent tumours. Solitary macular retinoblastoma should raise an index of suspicion for likely germline mutation and multifocal disease.

Trefoil Family Factor Peptide 1-A New Biomarker in Liquid Biopsies of Retinoblastoma under Therapy

Effective management of retinoblastoma (RB), the most prevalent childhood eye cancer, depends on reliable monitoring and diagnosis. A promising candidate in this context is the secreted trefoil family factor peptide 1 (TFF1), recently discovered as a promising new biomarker in patients with a more advanced subtype of retinoblastoma. The present study investigated TFF1 expression within aqueous humor (AH) of enucleated eyes and compared TFF1 levels in AH and corresponding blood serum samples from RB patients undergoing intravitreal chemotherapy (IVC). TFF1 was consistently detectable in AH, confirming its potential as a biomarker. Crucially, our data confirmed that TFF1-secreting cells within the tumor mass originate from RB tumor cells, not from surrounding stromal cells. IVC-therapy-responsive patients exhibited remarkably reduced TFF1 levels post-therapy. By contrast, RB patients' blood serum displayed low-to-undetectable levels of TFF1 even after sample concentration and no therapy-dependent changes were observed. Our findings suggest that compared with blood serum, AH represents the more reliable source of TFF1 if used for liquid biopsy RB marker analysis in RB patients. Thus, analysis of TFF1 in AH of RB patients potentially provides a minimally invasive tool for monitoring RB therapy efficacy, suggesting its importance for effective treatment regimens.

Transcriptome analysis reveals molecularly distinct subtypes in retinoblastoma

Retinoblastoma is the most frequent intraocular malignancy in children. Little is known on the molecular basis underlying the biological and clinical behavior of this cancer. Here, using gene expression profiles, we demonstrate the existence of two major retinoblastoma subtypes that can be divided into six subgroups. Subtype 1 has higher expression of cone related genes and higher percentage of RB1 germline mutation. By contrast, subtype 2 tumors harbor more genes with ganglion/neuronal features. The dedifferentiation in subtype 2 is associated with stemness features including low immune infiltration. Gene Otology analysis demonstrates that immune response regulations and visual related pathways are the key molecular difference between subtypes. Subtype 1b has the highest risk of invasiveness across all subtypes. The recognition of these molecular subtypes shed a light on the important biological and clinical perspectives for retinoblastomas.

Signaling pathways driving ocular malignancies and their targeting by bioactive phytochemicals

Ocular cancers represent a rare pathology. The American Cancer Society estimates that 3,360 cases of ocular cancer occur annually in the United States. The major types of cancers of the eye include ocular melanoma (also known as uveal melanoma), ocular lymphoma, retinoblastoma, and squamous cell carcinoma. While uveal melanoma is one of the primary intraocular cancers with the highest occurrence in adults, retinoblastoma remains the most common primary intraocular cancer in children, and squamous cell carcinoma presents as the most common conjunctival cancer. The pathophysiology of these diseases involves specific cell signaling pathways. Oncogene mutations, tumor suppressor mutations, chromosome deletions/translocations and altered proteins are all described as causal events in developing ocular cancer. Without proper identification and treatment of these cancers, vision loss, cancer spread, and even death can occur. The current treatments for these cancers involve enucleation, radiation, excision, laser treatment, cryotherapy, immunotherapy, and chemotherapy. These treatments present a significant burden to the patient that includes a possible loss of vision and a myriad of side effects. Therefore, alternatives to traditional therapy are urgently needed. Intercepting the signaling pathways for these cancers with the use of naturally occurring phytochemicals could be a way to relieve both cancer burden and perhaps even prevent cancer occurrence. This research aims to present a comprehensive review of the signaling pathways involved in various ocular cancers, discuss current therapeutic options, and examine the potential of bioactive phytocompounds in the prevention and targeted treatment of ocular neoplasms. The current limitations, challenges, pitfalls, and future research directions are also discussed.

Spotlight on Targeted Chemotherapy in Retinoblastoma: Safety, Efficacy, and Patient Outcomes

As the most common primary intraocular malignancy of childhood, retinoblastoma (RB) has had a complex journey in its management, following a course from enucleation as the first life-saving treatment to numerous globe-salvaging therapies during the last century. Currently, this potentially lethal disease has achieved high survival rates owing to multidisciplinary management and the introduction of neoadjuvant and multimodal chemotherapy. Therefore, the goal of treatment is shifting toward conserving the globe and vision as much as possible. Up until recently, many advanced cases of RB were enucleated primarily; however, targeted chemotherapy via the ophthalmic artery and management of intraocular seeding by local administration of chemotherapeutic agents have revolutionized the globe-conserving therapies. The added benefit of avoiding systemic complications of cytotoxic drugs resulted in these methods gaining popularity, and they are becoming a main part of care in many referral centers. Initially, there were some safety concerns regarding these approaches; however, increasing experience has shown that these modalities are relatively safe procedures and many complications can be averted by changing the choice of the drug and using some prophylactic measures. It is hoped that, in the near future, with advances in early diagnosis and patient-targeted molecular therapies, as well as gene-editing techniques, the patient's vision can be saved even in advanced RB.

Selective Induction of Intrinsic Apoptosis in Retinoblastoma Cells by Novel Cationic Antimicrobial Dodecapeptides

Host defense peptides represent an important component of innate immunity. In this work, we report the anticancer properties of a panel of hyper-charged wholly cationic antimicrobial dodecapeptides (CAPs) containing multiple canonical forms of lysine and arginine residues. These CAPs displayed excellent bactericidal activities against a broad range of pathogenic bacteria by dissipating the cytoplasmic membrane potential. Specifically, we identified two CAPs, named HC3 and HC5, that effectively killed a significant number of retinoblastoma (WERI-Rb1) cells (p ≤ 0.01). These two CAPs caused the shrinkage of WERI-Rb1 tumor spheroids (p ≤ 0.01), induced intrinsic apoptosis in WERI-Rb1 cells via activation of caspase 9 and caspase 3, cleaved the PARP protein, and triggered off the phosphorylation of p53 and γH2A.X. Combining HC3 or HC5 with the standard chemotherapeutic drug topotecan showed synergistic anti-cancer activities. Overall, these results suggest that HC3 and HC5 can be exploited as potential therapeutic agents in retinoblastoma as monotherapy or as adjunctive therapy to enhance the effectiveness of currently used treatment modalities.

Analysis of Cause-Specific Mortality in Patients with Retinoblastoma

Background. Retinoblastoma (RB) is a rare pediatric tumor with a relatively favorable prognosis. However, RB is associated with cause-specific mortality, some of that should be of great importance to clinicians. In this study, we summarize the characteristics of cause-specific mortality from nontumor disease in patients with RB. Methods. This retrospective case series study identified and analyzed cause-specific mortality in patients with RB. The information of cause-specific mortality of RB patients, including detailed clinical characteristics, diagnosis, treatment process, cause-specific mortality classification, and lag time, was assessed. Results. A total of 12 eligible patients were selected from 264 patients who died among 3780 patients diagnosed with RB. The cause-specific mortality rate was 4.5% for all patients with RB who died and 0.3% for all patients with RB. The main nontumor cause-specific mortalities were diseases of the nervous, circulatory, and respiratory systems, which specifically included intracranial infection, cerebral hemorrhage, paraplegia, and respiratory failure. The longest lag time was 42 days from the last chemoradiotherapy or surgery. Conclusion. Nontumor cause-specific mortality is an essential outcome of RB. Thus, intensive care and differentiation during management need to be taken seriously.

The role of m6A modification in pediatric cancer

With the development of RNA modification research, the importance of N6-methyladenosine (m6A) in tumors cannot be ignored. m6A promotes the self-renewal of tumor stem cells and the proliferation of tumor cells. It affects post-transcriptional gene expression through epigenetic mechanisms, combining various factors to determine proteins' fate and altering the biological function. This modification process runs through the entire tumors, and genes affected by m6A modification may be the critical targets for cancers breakthroughs. Though generally less dangerous than adult cancer, pediatric cancer accounts for a significant proportion of child deaths. What is more alarming is that the occurrences of adult tumors are highly associated with the poor prognoses of pediatric tumors. Therefore, it is necessary to pay attention to the importance of pediatric cancer and discover new therapeutic targets, which will help improve the therapeutic effect and prognoses of the diseases. We collected and investigated m6A modification in pediatric cancers based on mRNA and non-coding RNA, finding that m6A factors were involved in glioma, hepatoblastoma, nephroblastoma, neuroblastoma, osteosarcoma, medulloblastoma, retinoblastoma, and acute lymphoblastic leukemia. Consequently, we summarized the relationships between the m6A factors and these pediatric cancers.

Retinoblastoma: emerging concepts in genetics, global disease burden, chemotherapy outcomes, and psychological impact

In this review we discuss several recent concepts regarding retinoblastoma control and its impact. In a cohort of 482 patients with solitary unilateral retinoblastoma revealed germline mutation in 16% and the likelihood of germline retinoblastoma was greater for younger children (≤1 year versus (vs.) >1 year at presentation) with odds ratio (OR) 2.96 (p = 0.001), and greatest for the youngest infants (≤3 months vs. >3-12 months) (OR 5.52) (p = 0.002). Retinocytoma/retinoma, a benign variant of retinoblastoma, was studied in 78 tumours and demonstrated transformation into retinoblastoma in 9.2% by 5 years and 15.3% by 10 years and 20 years. An international global study on retinoblastoma over 1.5 years revealed 4351 new patients and 85% from low- and middle-income countries, notably with older age at detection and greater risk for metastasis. Management of retinoblastoma in 964 eyes using intravenous chemotherapy showed 20-year globe salvage at 96% in group A, 90% in group B, 90% in group C, 68% in group D, and 32% in group E eyes. The 5-year globe salvage with intra-arterial chemotherapy for 160 eyes (655 infusions) with retinoblastoma showed success in 100% for group B, 80% for group C, 78% for group D, and 55% for group E. The psychological impact of retinoblastoma on the parents revealed depression (73%), anxiety (64%), and/or stress (100%), and on the patient revealed deficits in quality of life issues. Retinoblastoma is a challenging disease and chemotherapy provides reliable tumour control and globe salvage. Continuing efforts to improve quality of life issues is important.

Knockdown of the Long Noncoding RNA TUG1 Suppresses Retinoblastoma Progression by Disrupting the Epithelial-Mesenchymal Transition

Taurine-upregulated gene 1 (TUG1) is a long noncoding RNA (lncRNA) that has previously been linked to the development and progression of several cancer types. Its expression and mechanistic role in retinoblastoma (RB), however, remains to be established. Herein, we found that RB tissue samples exhibited TUG1 upregulation. RB cell lines similarly exhibited marked TUG1 upregulation. Real-time cellular analysis (RTCA) and colony formation assays were then used to gauge RB cell proliferation, while transwell assays were conducted to assess the metastatic and invasive potential of these cells. In these assays, TUG1 upregulation was found to promote RB cell proliferative, migratory, and invasive activity while inducing the epithelial–mesenchymal transition (EMT). Subsequent quantitative real-time polymerase chain reaction (qPCR) and Western blotting indicated that this lncRNA functions at least in part by influencing the expression of Notch signaling pathway genes, which were downregulated following TUG1 knockdown in RB cells. Together, these data suggested that TUG1 can promote RB cell malignancy via the Notch signaling and EMT pathways, contributing to negative patient outcomes.

Intravitreal melphalan for persistent retinoblastoma vitreous seeds

A 7-month-old male presented with bilateral retinoblastoma, initially group E OD and group C OS (International Intraocular Retinoblastoma Classification). The patient underwent enucleation with adjuvant chemotherapy and radiotherapy on the right eye for extraocular retinoblastoma. The main tumors on the left eye regressed with combined neoadjuvant chemotherapy with focal therapy, but had persistent sphere vitreous seeds overlying the tumor at the superotemporal mid-periphery and at the inferior periphery. Intravitreal injection of melphalan was performed. Vitreous seeds were clinically undetectable after 2 cycles of injection. Six months from the 2^nd intravitreal injection of melphalan, there was no evidence of new tumors nor vitreous seeds in the left eye. No documented complications of intravitreal melphalan injection were experienced. This is the first documented successful treatment of vitreous seeds with intravitreal melphalan at the Ocular Oncology/Retinoblastoma Unit of the University of the Philippines, Philippine General Hospital.

AN IN VIVO STUDY OF INTRAVITREAL RANIBIZUMAB FOLLOWING SUBRETINAL INOCULATION OF RB CELLS IN RABBITS EYES

AIM

This study aimed to determine the effects of a single intravitreal ranibizumab injection in rabbits induced with retinoblastoma (RB).

MATERIAL AND METHODS

RB was induced in six New Zealand white rabbits by subretinal injection of a cultured WERI-RBb-1 cell line into the right eye. After six weeks, Group A (n = 3) was given intravitreal ranibizumab injection (0.3mg in 0.03ml) and Group B (n = 3) was the control. Baseline and serial clinical examinations were performed on days 1, 3, 6, 12, 15, 18 and 21. The right eyes were enucleated for both groups on day 21 for histopathological examination.

RESULTS

The rabbits in both groups developed intraocular lesions which was detectable clinically at one-week post-tumor inoculation. The tumor grew slowly without spontaneous regression. After the animals in Group A were given an intravitreal ranibizumab injection, regression of the tumor was detected clinically, while the tumor in Group B continued to grow slowly. Histopathological findings confirmed the presence of a tumor that closely resembled features of poorly differentiated human RB cells. At the end of 21 days, the size of the tumor was larger in Group B in comparison to Group A. However, the treated group also developed a focal area of retinal hyperplasia. There was no significant side effect of ranibizumab injection except temporary high intraocular pressure immediately post-injection, which was relieved after paracentesis.

CONCLUSIONS

Intravitreal ranibizumab is a potential treatment for RB. It is an effective therapy with a tolerable safety profile in this animal experimental study.

Quantitative evaluation of retinal microvasculature and retrobulbar vessels after intravenous chemotherapy for retinoblastoma

Backgroud

To evaluate the changes in retinal microvasculature and retrobulbar blood flow, using optical coherence tomography angiography (OCTA) and Color Doppler imaging (CDI) after intravenous chemotherapy (IVC) in patients with retinoblastoma (RB).

Methods

This was a retrospective comparative case control series involving 30 patients. Ten bilateral RB patients that had a preserved eye with extramacular tumours (group I), 10 unilateral RB treated with IVC that had a normal fellow study eye (group II), and 10 age-matched healthy controls. The macular retinal thickness, foveal avascular zone (FAZ) area, and the macular and peripapillary retinal vessel densities (RVD) were measured. The peak systolic and end diastolic velocities of the ophthalmic, central retinal and posterior ciliary arteries were determined. A comparison among the three groups was conducted.

Results

Between the three cohorts, OCTA revealed no significant difference in FAZ area, superficial foveal and parafoveal RVD, deep parafoveal RVD and peripapillary RVD, (P > 0.05). By contrast, the mean deep foveal RVD, the full, inner and outer foveal and the parafoveal retinal thickness were significantly lower in group I compared with the controls, (P = 0.0329, 0.0153, 0.0311 0.0352, 0.0215). No significant difference in the blood flow velocities occurred in the retrobulbar circulation (P > 0.05).

Conclusions

In patients with retinoblastoma, OCTA did not detect significant changes of retinal thickness and vessel density in the eyes treated with IVC, but a slight reduction in retinal thickness and the deep foveal RVD seemed to occur in bilateral RB eyes. The retrobulbar blood flow parameters showed no measurable changes.

Single-cell transcriptome profiling reveals intratumoural heterogeneity and malignant progression in retinoblastoma

Retinoblastoma is a childhood retinal tumour that is the most common primary malignant intraocular tumour. However, it has been challenging to identify the cell types associated with genetic complexity. Here, we performed single-cell RNA sequencing on 14,739 cells from two retinoblastoma samples to delineate the heterogeneity and the underlying mechanism of retinoblastoma progression. Using a multiresolution network-based analysis, we identified two major cell types in human retinoblastoma. Cell trajectory analysis yielded a total of 5 cell states organized into two main branches, and the cell cycle-associated cone precursors were the cells of origin of retinoblastoma that were required for initiating the differentiation and malignancy process of retinoblastoma. Tumour cells differentiation reprogramming trajectory analysis revealed that cell-type components of multiple tumour-related pathways and predominantly expressed UBE2C were associated with an activation state in the malignant progression of the tumour, providing a potential novel "switch gene" marker during early critical stages in human retinoblastoma development. Thus, our findings improve our current understanding of the mechanism of retinoblastoma progression and are potentially valuable in providing novel prognostic markers for retinoblastoma.

Likelihood of Germline Mutation With Solitary Unilateral Retinoblastoma Based on Patient Age at Presentation: Analysis of 482 Consecutive Patients

PURPOSE

To evaluate the likelihood of germline retinoblastoma in patients presenting with solitary unilateral retinoblastoma, based on age at presentation.

METHODS

This retrospective case series of 482 consecutive patients presenting with solitary unilateral retinoblastoma analyzed the likelihood of germline retinoblastoma, defined as family history of retinoblastoma, germline retinoblastoma mutation documented on genetic testing, and/or development of bilateral disease and/or additional new tumors. This analysis was based on age at presentation (0 to 12 months vs older than 12 to 24 months vs older than 24 to 36 months vs older than 36 months) and a sub-study was conducted on infant age at presentation (0 to 3 months vs older than 3 to 6 months vs older than 6 to 9 months vs older than 9 to 12 months).

RESULTS

Of the overall group (482 consecutive patients) with solitary unilateral retinoblastoma, there were significantly different findings in the youngest age group (0 to 12 months old) with greater family history of retinoblastoma (10% vs 2% vs 1% vs 2%, P = .004), smaller median basal diameter (18.0 vs 20.0 vs 20.0 vs 20.0 mm, P = .014), smaller median tumor thickness (8.7 vs 10.0 vs 11.5 vs 10.0 mm, P = .002), greater macular tumor location (33% vs 16% vs 10% vs 8%, P < .001), and greatest likelihood of germline mutation (29% vs 17% vs 8% vs 9%, P = .001). By comparison, patients 1 year and younger (vs older than 1 year) demonstrated a 2.96 odds ratio (OR) (P = .001) for likelihood of germline retinoblastoma. For those classified as infants (1 year and younger) (n = 132 consecutive patients), the youngest patients (0 to 3 months old) demonstrated the greatest likelihood for germline mutation (61% vs 20% vs 24% vs 22%, P = .009) and greatest odds ratio (5.52, P = .002) compared to patients older than 3 to 12 months.

CONCLUSIONS

The youngest patients with solitary unilateral retinoblastoma showed the greatest likelihood of germline disease when evaluating all patients (1 year and younger vs older than 1 year of age) (OR = 2.96) and the substudy of infants (3 years and younger vs older than 3 to 12 months old) (OR = 5.52). [J Pediatr Ophthalmol Strabismus. 2021;58(6):355-364.].

Carboplatin- and Etoposide-Loaded Lactoferrin Protein Nanoparticles for Targeting Cancer Stem Cells in Retinoblastoma In Vitro

Purpose

Cancer stem cells (CSCs) are known to contribute to tumor relapses by virtue of their chemoresistance. With the knowledge that nanoformulations can overcome drug resistance, we evaluated the efficacy and cytotoxicity of clinical-grade carboplatin (CPT)– and etoposide (ETP)–loaded lactoferrin nanoparticles (Lf-Nps) on total, CD133-enriched (non-CSC), and CD133-depleted (CSC) populations of retinoblastoma (Rb) Y79 cells.

Methods

Physicochemical properties of drug-loaded Lf-Nps were measured with transmission electron microscopy and attenuated total reflectance–Fourier transform infrared. The encapsulation efficiency, uptake, and release of drug-loaded Lf-Nps were measured using high-performance liquid chromatography and a UV-visible spectrophotometer. Cytotoxicity of the standard and drug-loaded Lf-Nps was evaluated by the MTT assay.

Results

The mean (SD) size and encapsulation efficiency of Lf-CPT and Lf-ETP were 61.2 (3.94) nm, 60% and 45.15 (5.85) nm, 38%, respectively, and the drug release efficiency was highest at pH 6. The increased drug uptake and lower release of drug-loaded Lf-Nps were observed in CSC and non-CSC populations compared to their standard forms. The relative increase of drug uptake and sustained intracellular retention of the drug-loaded Lf-Nps compared to standard drugs showed an enhanced cytotoxicity up to 50%, especially in Rb Y79 CSCs (IC₅₀: CPT, 230.3; Lf-CPT, 118.2; ETP, 198.1; and Lf-ETP, 129) compared to non-CSCs.

Conclusions

Our study documents an increase in drug uptake, retention, and cytotoxicity of Lf-CPT and Lf-ETP on Y79 CSCs and non-CSCs as compared to their standard drugs in vitro. The reversal of chemoresistance in the CSC population by nanoformulation appears promising with the potential to pave the way for improved targeted therapy and better clinical outcomes.

Ultrasound and Microbubbles for the Treatment of Ocular Diseases: From Preclinical Research towards Clinical Application

The unique anatomy of the eye and the presence of various biological barriers make efficacious ocular drug delivery challenging, particularly in the treatment of posterior eye diseases. This review focuses on the combination of ultrasound and microbubbles (USMB) as a minimally invasive method to improve the efficacy and targeting of ocular drug delivery. An extensive overview is given of the in vitro and in vivo studies investigating the mechanical effects of ultrasound-driven microbubbles aiming to: (i) temporarily disrupt the blood–retina barrier in order to enhance the delivery of systemically administered drugs into the eye, (ii) induce intracellular uptake of anticancer drugs and macromolecules and (iii) achieve targeted delivery of genes, for the treatment of ocular malignancies and degenerative diseases. Finally, the safety and tolerability aspects of USMB, essential for the translation of USMB to the clinic, are discussed.

Recurrence and new tumor development after frontline intravenous chemotherapy for retinoblastoma: Risk factors and treatment results

PURPOSE

To evaluate the risk factors leading to recurrence and new tumor (NT) development in patients with retinoblastoma after intravenous chemotherapy (IVC) and to review the treatment outcomes.

MATERIALS AND METHODS

The records of 166 retinoblastoma cases (having 246 affected eyes) who underwent six-cycle IVC (vincristine, etoposide, and carboplatin) as primary treatment between October 1999 and August 2020 were reviewed retrospectively.

RESULTS

The mean ages at presentation were 9.0 (median: 8.0) and 9.2 (median: 8.5) months in cases with recurrence and NTs respectively. Recurrence was detected in 40 (16.3%) eyes, NTs in 29 (11.8%), and both recurrence/NTs in 24 (9.8%). The mean time elapsed till recurrence and NT was 10.7 months. Multivariable analysis showed that the factors predictive of recurrence were largest tumor base diameter (LTBD) >12 mm (p = 0.039) and presence of subretinal seeds at diagnosis (p = 0.043). Multivariable risk factors for the development of NTs were bilateral familial retinoblastoma (p = 0.001) and presence of subretinal seeds at diagnosis (p = 0.010). Mean follow-up was 80.1 (median: 72.5) months. By Kaplan-Meier analysis, the 1-, 3-, and 6-year recurrence and NT rates were 21.2%, 28.1%, and 28.7% and 14.9%, 22.6%, and 23.9% respectively. The most common treatment methods used for recurrent and/or NTs included cryotherapy, transpupillary thermotherapy, and intra-arterial chemotherapy. Enucleation was eventually required in 24/93 (25.8%) eyes. No patient developed metastasis.

DISCUSSION

Development of recurrence and/or NT after IVC was noted in 38% of all retinoblastoma eyes. Bilateral familial disease, LTBD >12 mm, and presence of subretinal seeds at baseline were risk factors for recurrence and NTs in this study.

Intra-arterial chemotherapy for retinoblastoma in 341 consecutive eyes (1,292 infusions): comparative analysis of outcomes based on patient age, race, and sex

PURPOSE

To evaluate tumor control and globe salvage following intra-arterial chemotherapy (IAC) for retinoblastoma based on International Classification of Retinoblastoma (ICRB) and patient demographics.

METHODS

The medical records of 313 patients (341 eyes) treated with IAC were reviewed retrospectively. Chemotherapy agents included melphalan, topotecan, and carboplatin. Comparative analysis was performed for tumor control and globe salvage based on ICRB and patient demographics including age (≤12 vs >12 months), race (white vs nonwhite), and sex.

RESULTS

Of the 341 eyes treated with 1,292 consecutive infusions of IAC as primary or secondary therapy for retinoblastoma, Kaplan-Meier 5-year estimates of globe salvage was 74%. Of those treated with IAC as primary therapy (n = 160 eyes; 655 infusions), 5-year globe salvage overall was 76%: and more specifically, 100% for groups B and C, 86% for group D, and 55% for group E. Of those treated with IAC as secondary therapy (n = 207 eyes; 859 infusions), 5-year globe salvage was 71%. Comparative analysis by race and sex demonstrated no differences in outcomes, but analysis by age revealed that younger patients had a higher rate of globe salvage (77% vs 72%; P < 0.001). Complications (per catheterization) included retina ischemia (1%), choroidal ischemia (1%), neovascularization of the disk, retina, iris (NVI), glaucoma (about 1% each), and central/peripheral systemic ischemia (<1%). Younger patients showed less NVI (P = 0.028), white patients showed less retinal ischemia (P = 0.037), and no difference by sex. There were no patients with metastatic disease or death.

CONCLUSIONS

Our results suggest that IAC provides substantial tumor control for advanced and/or recurrent retinoblastoma with a high rate of globe salvage and few complications. There was little difference in outcomes per age, race, and sex.

Retinoblastoma: from discovery to clinical management

The retinoblastoma gene (RB1) was the first tumour suppressor cloned; the role of its protein product (RB) as the principal driver of the G1 checkpoint in cell cycle control has been extensively studied. However, many other RB functions are continuously reported. Its role in senescence, DNA repair and apoptosis, among others, is indications of the significance of RB in a vast network of cellular interactions, explaining why RB loss or its malfunction is one of the leading causes of a large number of paediatric and adult cancers. RB was first reported in retinoblastoma, a common intraocular malignancy in the paediatric population worldwide. Currently, its diagnosis is clinical, and in nondeveloped countries, where the incidence is higher, it is performed in advanced stages of the disease, compromising the integrity of the eye and the patient's life. Even though new treatments are being continuously developed, enucleation is still a major choice due to the late disease stage diagnosis and treatments costs. Research into biomarkers is our best option to improve the chances of good results in the treatment and hopes of patients' good quality of life. Here, we recapitulated the history of the disease and the first treatments to put the advances in its clinical management into perspective. We also review the different functions of the protein and the progress in the search for biomarkers. It is clear that there is still a long way to go, but we should offer these children and their families a better way to deal with the disease with the community's effort.

Risk factors for ophthalmic artery stenosis and occlusion in patients with retinoblastoma treated with intra-arterial chemotherapy

Purpose

To explore the risk factors for ophthalmic artery (OA) stenosis and occlusion after intra-arterial chemotherapy (IAC) with selective ophthalmic artery catheterisation (OAC) in the treatment of retinoblastoma.

Design

Retrospective, single centre case-control study.

Methods

The study was conducted including consecutive patients with unilateral or bilateral intraocular retinoblastoma undergoing IAC between June 2016 and June 2019 with a follow-up time of 4 years. Main outcomes are rate of IAC-induced OA occlusion and OA diameter.

Results

346 attempted OAC infusions were successful. The total incidence of OA occlusion was 15.89%. The occlusion and control groups were similar in patients’ age, sex and disease stage. Median OA diameter was 0.49 mm in those with OA occlusion, and 0.66 mm in those without occlusion. In the occlusion group, the OA diameter difference was significantly larger between the first IAC and the final IAC (0.22mm vs 0.12mm, p=0.001). In both groups, the median number of IAC treatments was 3. Multivariate Cox regression models included initial OA diameter (OR: 0.005, p=0.001), ratio of OA orifice diameter differences between first and last IAC to the initial OA orifice diameter (OR: 4.661, p=0.003), and number of IAC (OR: 1.538, p=0.042) as clinical features significantly associated with OA occlusion.

Conclusions

The OA diameter at first IAC treatment, the ratio of OA orifice diameter differences between first and last IAC to the initial OA orifice diameter and total number of IAC treatments may be three main clinical predictors for OA occlusion after IAC for retinoblastoma.

The role for intra-arterial chemotherapy for refractory retinoblastoma: a systematic review

BACKGROUND

Intra-arterial chemotherapy is a new retinoblastoma treatment associated with high rates of globe salvage that has been widely adopted for primary treatment of retinoblastoma but is less frequently used as secondary treatment for refractory retinoblastoma. This systematic review aims to summarize the reported outcomes of intra-arterial chemotherapy for refractory retinoblastoma.

METHODS

We conducted a systematic review of studies published on PubMed, Medline, and Embase from 2011 to 2021 reporting globe salvage rates following intra-arterial chemotherapy for secondary treatment of refractory retinoblastoma.

RESULTS

Our search yielded 316 studies, and 24 met inclusion criteria. The 24 included studies were comprised of 1366 patients and 1757 eyes. Among these, 1184 (67%) eyes received secondary indication treatment, and globe salvage was achieved for 776 of these 1184 eyes (64%). Sixteen studies reported cannulation success rates from 71.8 to 100%. Pooled analysis of subjects revealed 21 patients (2.6%) with metastatic disease and 26 deaths (3%) during study follow-up periods (7-74 months). The most common ocular complications were vitreous hemorrhage (13.2%), loss of eyelashes (12.7%), and periocular edema (10.5%). The most common systemic complications were nausea/vomiting (20.5%), neutropenia (14.1%), fever (8.2%), and bronchospasm (6.2%).

CONCLUSIONS

Intra-arterial chemotherapy is associated with high rates of globe salvage and low rates of serious complications in patients with refractory retinoblastoma. Unfortunately, current literature is predominantly comprised of retrospective case studies, and further high-quality evidence is necessary to inform clinical practice.

Retinoblastoma: What the Neuroradiologist Needs to Know

Retinoblastoma is the most common primary intraocular tumor of childhood. Accurate diagnosis at an early stage is important to maximize patient survival, globe salvage, and visual acuity. Management of retinoblastoma is individualized based on the presenting clinical and imaging features of the tumor, and a multidisciplinary team is required to optimize patient outcomes. The neuroradiologist is a key member of the retinoblastoma care team and should be familiar with characteristic diagnostic and prognostic imaging features of this disease. Furthermore, with the adoption of intra-arterial chemotherapy as a standard of care option for globe salvage therapy in many centers, the interventional neuroradiologist may play an active role in retinoblastoma treatment. In this review, we discuss the clinical presentation of retinoblastoma, ophthalmic imaging modalities, neuroradiology imaging features, and current treatment options.

Modern treatment of retinoblastoma: A 2020 review

Retinoblastoma management remains complex, requiring individualized treatment based on International Classification of Retinoblastoma (ICRB) staging, germline mutation status, family psychosocial factors and cultural beliefs, and available institutional resources. For this 2020 retinoblastoma review, PubMed was searched for articles dated as early as 1931, with an emphasis on articles from 1990 to the present day, using keywords of retinoblastoma, chemotherapy, intravenous chemotherapy, chemoreduction, intra-arterial chemotherapy, ophthalmic artery chemosurgery, intravitreal chemotherapy, intracameral chemotherapy, cryotherapy, transpupillary thermotherapy, laser, radiation, external beam radiotherapy, plaque radiotherapy, brachytherapy, and enucleation. We discuss current treatment modalities as used in the year 2020, including intravenous chemotherapy (IVC), intra-arterial chemotherapy (IAC), intravitreal chemotherapy (IvitC), intracameral chemotherapy (IcamC), consolidation therapies (cryotherapy and transpupillary thermotherapy [TTT]), radiation-based therapies (external beam radiotherapy [EBRT] and plaque radiotherapy), and enucleation. Additionally, we present a consensus treatment algorithm based on the agreement of three North American retinoblastoma treatment centers, and encourage further collaboration amongst the world's most expert retinoblastoma treatment centers in order to develop consensus management plans and continue advancement in the identification and treatment of this childhood cancer.

Penetration of Carbon Nanotubes into the Retinoblastoma Tumor after Intravitreal Injection in LH BETA T AG Transgenic Mice Reti-noblastoma Model

Purpose

To evaluate the penetration of carbon nanotubes (CNTs) throughout retinoblastoma in a transgenic mice model.

Methods

CNTs functionalized with fluorescein isothiocyanate and targeting ligands biotin (CTN-FITC-Bio, 0.5mg/ml), or folic acid (CNT-FITC-FA, 0.5mg/ml) were injected into the vitreous of one eye of LH BETA T AG transgenic mice. Other eye did not receive any injection and was used as control. Three mice were sacrificed at days 1, 2, and 3. Eyes were enucleated and stained with 4,6-diamidino-2-phenylindole. The sections were imaged by fluorescent microscope. The images were transformed into grey-scale in MATLAB for intensity analysis. Background intensity was normalized by marking squares outside the eyeball and using the mean intensity of these squares. Fluorescent intensity (FI) for each image was measured by calculating the intensity of a same-sized square within retinoblastoma.

Results

Nine eyes of nine mice were included in each CNT-FITC-Bio and CNT-FITC-FA groups. The mean FI in CNT-FITC-Bio was 52.08 ± 6.33, 53.62 ± 9.00, and 65.54 ± 5.14 in days 1, 2, and 3, respectively. The mean FI in CNT-FITC-FA was 50.28 ± 7.37, 59.21 ± 6.43, and 58.38 ± 2.32 on days 1, 2, and 3, respectively. FI was significantly higher in eyes injected with CNT-FITC-Bio and CNT-FITC-FA compared to the control eyes (P = 0.02). There was no difference in FI between eyes with CNT-FITC-Bio and CNT-FITC-FA, and FI remained stable on days 1–3 in CNT-FITC-Bio, CNT-FITC-FA, and control eyes (P> 0.05).

Conclusion

We observed higher FI in eyes with CNT-FITC-Bio and CNT-FITC-FA compared to control eyes, showing penetration of CNTs throughout retinoblastoma. CNTs can be a carrier candidate for imaging or therapeutic purposes in retinoblastoma.

Efficacy of systemic administration of riboflavin on a rabbit model of corneal alkali burn

Changes in the barrier mechanisms in the eye should determine the rational route for the administration and dosage of each drug in the treatment of traumatic injuries and other pathologies. The aim of this study was to examine the efficacy of intra-arterial delivery of 14C-riboflavin (as an "indicator") and compare it with intravenous and intramuscular administration in an animal model of chemical eye burn. 14C-riboflavin (14C-I) was administered by intra-arterial (carotid artery), intravenous (femoral vein) and intramuscular (femoral muscle) routes. The total radioactivity was determined over 2 h in the plasma and structures of the rabbit's eyes using a scintillation counter. The results of the study show that intravascular administration of 14C-I gives significantly higher concentrations of total radioactivity in the blood and is accompanied by a significant increase in the permeability of the blood-barrier and barrier in eyes suffering from burns. The highest concentration in the plasma and aqueous humour of the anterior chamber of the eye was observed during the first hour with the intra-arterial route of administration of 14C-I in either burnt and unburnt eyes. The distribution of total radioactivity in the structures of the eye over the 2 h of the experiment showed a higher level of the drug under intra-arterial administered in the uveal regions, namely: the iris, ciliary body, choroid, retina and also the sclera and cornea. This experimental model shows that intra-arterial administration can increase the bioavailability of a drug to the structures of the eye within a short period of time.

An Overview of Retinoblastoma and Enucleation in Pediatric Patients

Retinoblastoma is a rare malignancy of the eye affecting children, most commonly four years old and younger. Although chemotherapy and radiation treatment aim to spare the eye, in some cases, enucleation (ie, removal of the eye) is required to prevent cancer metastases or recurrence. Enucleation procedures are primarily performed at specialty institutions and may involve the surgical placement of an implant in the orbit of the eye. Unique perioperative considerations are required because of the age of the child at the time of the diagnosis and procedure and the involvement of a parent or caregiver who will be caring for the child postoperatively. This article presents an overview of retinoblastoma and enucleation and discusses the care and management of the unique patient population undergoing enucleation.

Clinical spectrum and treatment outcome of retinoblastoma with Group D and E diseases: A single institution retrospective review

The purpose of our study was to evaluate the ocular survival and event-free survival after multimodal therapy for group D and E of retinoblastoma (RB). Enucleation of group D and E is controversial as the risks of chemotherapy must be weighed against the potential for vision.A 10-year retrospective study from one center of 86 patients with advanced intraocular disease defined as International Classification Retinoblastoma (ICRB) group "D" or "E." Cases with visible extraocular extension at diagnosis were excluded. Ocular survival and patient survival were assessed. Indirect ophthalmoscopy at examination under anesthesia to visualize the tumor was used to evaluate clinical response.The median onset age in 86 patients with group D or E eye was 16 months (1-167 months). There were 29 (34%) bilateral cases. Leukocoria was the most common presentation sign (61%). Chemoreduction was primarily used in the treatment of intraocular RB. Selective ophthalmic arterial injection (SOAI) was applied as a component of multimodal therapy in 34 of the 86 cases. The globe preservation rate in patients with group D or E eyes was 19%. Using chemoreduction for advanced eyes, more eyes are being preserved which enables 70% 5-year ocular survival in patients with group D eyes.In triaging appropriate patients, multidisciplinary strategy can reduce tumor size with chemoreduction and consolidate the regressed tumor with local ophthalmic therapy to ensure globe salvage.

A single-arm study of systemic and sub-Tenon chemotherapy for Groups C and D intraocular retinoblastoma: A Children's Oncology Group study (ARET 0231)

BACKGROUND

Eyes with Group D intraocular retinoblastoma have low salvage rates. A pilot study showed safety and efficacy of sub-Tenon's fascia carboplatin with systemic chemotherapy supporting further study.

METHODS

Children with newly diagnosed bilateral intraocular retinoblastoma with at least one remaining Group C or D eye were treated with six courses of carboplatin/etoposide/vincristine (CEV) with sub-Tenon's fascia carboplatin for Group C/D eyes during courses 2-4. Local ophthalmic therapy started at course 3. The primary study objective was to determine the 1-year failure rate of Group D eyes.

RESULTS

The study closed prematurely due to poor accrual and 22 of 30 patients were evaluable for failure rate, contributing 25 Group D and four Group C eyes. Among the 25 Group D eyes, there were 13 failures within the first year of study enrollment including eight needing external beam radiotherapy (EBR) and five needing enucleation, resulting in 1-year failure rate of 52%. The failure rate was significantly lower than the historical rate of 70% (P = .039). The 1-year eye preservation rate for Group D eyes was 80% (20/25). One-year failure rate for Group C eyes was 25% (1/4); 1-year preservation rate was 100% without need for EBR. Systemic toxicity included Grade 3 hearing loss in two subjects, infections, neutropenia, and thrombocytopenia. Ocular toxicities included periorbital fat atrophy (13/29 = 45% eyes), optic nerve atrophy (1/29 = 3% eyes), and restrictive fibrosis (1/29 = 3% eyes).

CONCLUSIONS

Sub-Tenon's fascia carboplatin plus CEV was partially effective in Group D intraocular retinoblastoma but had unacceptable ocular toxicities.

Effectiveness of intravitreal chemotherapy-assisted endoresection in monocular patients with group D retinoblastoma

Background

This study aimed to determine the efficacy and complications of intravitreal chemotherapy-assisted endoresection for refractory International Classification of Retinoblastoma (ICRB) group D retinoblastoma in monocular patients.

Methods

In this retrospective case series, intravitreal chemotherapy-assisted endoresection by pars plana vitrectomy was performed in 11 eyes with refractory ICRB group D retinoblastoma unresponsive to standard therapies in monocular patients.

Results

Across a mean follow-up period of 42.7 months, globe salvage was attained in all 11 eyes (100%). There were no cases of extra-ocular tumour seeding or remote metastasis. In 9 eyes (81.8%), tumour control was achieved with one pars plana vitrectomy; in 2 cases (18.2%), repeated treatment, such as laser therapy, intravitreal chemotherapy or a second pars plana vitrectomy, was needed. Retinal reattachment was achieved in all 4 eyes (100%) with previous retinal detachment. Four eyes (36.4%) required subsequent cataract surgery due to secondary cataract. Ten eyes (90.9%) had improvement in best-corrected visual acuity at the last follow-up.

Conclusion

Intravitreal chemotherapy-assisted endoresection appears to be a safe and effective globe-salvaging method for refractory group D retinoblastoma. It is a promising alternative to enucleation and a supplementary therapeutic strategy for those unresponsive to standard therapies, especially for the monocular retinoblastoma patients.

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.

Outcomes of neonatal retinoblastoma in pre-chemotherapy and chemotherapy eras

Purpose

To quantify outcomes for neonatal retinoblastoma patients treated during the pre-chemotherapy (1980-1994) and chemotherapy (1995-2018) eras.

Methods

Retrospective review of retinoblastoma patients diagnosed within the first 28 days of life between 1/1/1980 and 11/30/2018. Student's t-test, Chi-square, and Fisher's exact test were performed to compare treatments and outcomes by era.

Results

There were 68 patients with neonatal retinoblastoma (12% unilateral and 88% bilateral). According to era (pre-chemotherapy vs. chemotherapy), the number of treated patients was 26 (38%) vs. 42 (62%). Primary treatment was external beam radiotherapy (50% vs. 1%,P < 0.001), plaque radiotherapy (17% vs. 0%,P < 0.001), focal treatment (transpupillary thermotherapy or cryotherapy) only (21% vs. 14%,P= 0.33), intravenous chemotherapy (0% vs. 81%,P < 0.001), enucleation (10% vs. 4%,P= 0.26), or exenteration (2% vs. 0%,P= 0.37). Outcomes included tumor control (79% vs. 94%,P= 0.02), globe salvage (75% vs. 91%,P= 0.02), final gross visual acuity for salvaged eyes 20/200 or better (66% vs. 89%,P < 0.01), and death (19% vs. 0%,P < 0.01).

Conclusion

Chemotherapy advancements for neonatal retinoblastoma have improved tumor control, globe salvage, visual acuity, and patient survival.