Retinoblastoma in Asia: Clinical Presentation and Treatment Outcomes in 2112 Patients from 33 Countries.

PURPOSE: To describe the clinical presentation and treatment outcomes of children who received a diagnosis of retinoblastoma in 2017 throughout Asia. DESIGN: Multinational, prospective study including treatment-naïve patients in Asia who received a diagnosis of retinoblastoma in 2017 and were followed up thereafter. PARTICIPANTS: A total of 2112 patients (2797 eyes) from 96 retinoblastoma treatment centers in 33 Asian countries. INTERVENTIONS: Chemotherapy, radiotherapy, enucleation, and orbital exenteration. MAIN OUTCOME MEASURES: Enucleation and death. RESULTS: Within the cohort, 1021 patients (48%) were from South Asia (SA), 503 patients (24%) were from East Asia (EA), 310 patients (15%) were from Southeast Asia (SEA), 218 patients (10%) were from West Asia (WA), and 60 patients (3%) were from Central Asia (CA). Mean age at presentation was 27 months (median, 23 months; range, < 1-261 months). The cohort included 1195 male patients (57%) and 917 female patients (43%). The most common presenting symptoms were leukocoria (72%) and strabismus (13%). Using the American Joint Committee on Cancer Staging Manual, Eighth Edition, classification, tumors were staged as cT1 (n = 441 [16%]), cT2 (n = 951 [34%]), cT3 (n = 1136 [41%]), cT4 (n = 267 [10%]), N1 (n = 48 [2%]), and M1 (n = 129 [6%]) at presentation. Retinoblastoma was treated with intravenous chemotherapy in 1450 eyes (52%) and 857 eyes (31%) underwent primary enucleation. Three-year Kaplan-Meier estimates for enucleation and death were 33% and 13% for CA, 18% and 4% for EA, 27% and 15% for SA, 32% and 22% for SEA, and 20% and 11% for WA (P < 0.0001 and P < 0.0001), respectively. CONCLUSIONS: At the conclusion of this study, significant heterogeneity was found in treatment outcomes of retinoblastoma among the regions of Asia. East Asia displayed better outcomes with higher rates of globe and life salvage, whereas Southeast Asia showed poorer outcomes compared with the rest of Asia. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Captains on call: A qualitative investigation of an intervention to support children with retinoblastoma undergoing regular eye examinations.

BACKGROUND: Retinoblastoma is a rare childhood ophthalmic cancer that requires frequent eye examinations under anaesthesia and painful or distressing procedures. This can cause significant anxiety for children and their families. OBJECTIVE: We evaluated a Starlight Children's Foundation programme, 'Captains on Call', at the Queensland Children's Hospital, which aims to provide positive distraction and reduce stress, anxiety and pain during the perioperative journey for children in the retinoblastoma treatment pathway. This study examined the impact of the programme on the perioperative experience of the children and their families, using a qualitative design. METHODS: This study was conducted in a paediatric operating suite at a tertiary-level children's hospital in Australia. We interviewed a parent from 20 families (from a cohort of 40 families, including 44 children), whose children received treatment or screening for retinoblastoma, focusing on the programme's impact on the child and family at various stages during the perioperative journey. We undertook a thematic analysis of transcribed interviews. RESULTS: We identified two themes, each with two sub-themes: (1) the programme positively contributed to the overall treatment journey, by addressing different needs at different times, and helping to reframe a traumatic medical experience, and (2), the programme supported the whole family unit by empowering children through play, and adopting a family systems approach which recognised the impact of cancer treatment on the whole family. CONCLUSION: This study highlights the value of the Captains on Call programme in supporting children with retinoblastoma and their families during perioperative visits. The Captains, particularly as non-medicalised professionals in a healthcare setting, built trust and rapport with the children through play over repeated episodes of care. The interprofessional collaborative approach with a reflective cycle of practice extended it beyond a programme providing simple distraction. Other retinoblastoma services may benefit from implementing a similar approach.

Strategies to improve diagnosis and access to treatment of retinoblastoma in low- and middle-income countries: A systematic review.

Retinoblastoma, the most common intraocular tumor in childhood, still faces challenges in diagnosis and treatment, particularly in low- and middle-income countries. Identifying strategies to improve the time to diagnosis and access to treatment is crucial to enhance survival rates and preserve ocular health. We conducted a systematic review to identify interventions that have demonstrated potential in addressing these challenges. We performed a comprehensive search across databases until March 2023. Out of the studies reviewed, 21 met the inclusion criteria and were categorized into five main areas: surveillance strategies, genetic counseling, education, public assistance, and international partnership. Despite the obstacles faced, the initiatives identified in this review present acts toward improving the time to diagnosis and access to treatment for retinoblastoma. Based on the extracted data, we propose a comprehensive chain of initiatives. We firmly believe that implementing this chain of initiatives can lead to improved clinical outcomes for retinoblastoma patients.

A multi-institutional feasibility study of intra-arterial chemotherapy in children with retinoblastoma. A Children's Oncology Group study (COG ARET12P1).

BACKGROUND: Intra-arterial chemotherapy (IA) as a treatment to salvage the eye with advanced retinoblastoma is increasingly utilized based on successes reported by institutions around the world mainly through retrospective studies. OBJECTIVE: To study the feasibility of delivering melphalan directly into the ophthalmic artery in a multi-institutional prospective study in children with newly diagnosed unilateral group D retinoblastoma. METHODS: The Children's Oncology Group (COG) initiated study ARET12P1 in 2014 and was open to nine institutions. Eligible patients older than six months of age were enrolled. The feasibility of delivering three injections of melphalan into the ophthalmic artery every 28 days was assessed. RESULTS: Nine institutions participated in this trial. Fourteen patients were enrolled, two of whom were unevaluable for feasibility. Four patients experienced a feasibility failure. In two patients, the ophthalmic artery could not be accessed for the second IA injection, in one the artery could not be accessed for the first injection, and one patient experienced grade 4 hypotension during the procedure. CONCLUSION: Delivery of prescribed therapy within the context of this study did not meet the feasibility goals of the study with only a 67% feasibility success rate. These results should caution centers that plan to initiate this treatment and suggest investment in training to achieve technical expertise or referral to centers with expertise.

Germline HPF1 retrogene insertion in RB1 gene involved in cancer predisposition.

About half of the human genome is composed of repeated sequences derived from mobile elements, mainly retrotransposons, generally without pathogenic effect. Familial forms of retinoblastoma are caused by germline pathogenic variants in RB1 gene. Here, we describe a family with retinoblastoma affecting a father and his son. No pathogenic variant was identified after DNA analysis of RB1 gene coding sequence and exon-intron junctions. However, RB1 mRNA analysis showed a chimeric transcript with insertion of 114 nucleotides from HPF1 gene inside RB1 gene. This chimeric transcript led to an insertion of 38 amino acids in functional domain of retinoblastoma protein. Subsequent DNA analysis in RB1 intron 17 revealed the presence of a full-length HPF1 retrogene insertion in opposite orientation. Functional assay shows that this insertion has a deleterious impact on retinoblastoma protein function. This is the first report of a full-length retrogene insertion involved in human Mendelian disease leading to a chimeric transcript and a non-functional chimeric protein. Some retrogene insertions may be missed by standard diagnostic genetic testing, so contribution of retrogene insertions to human disease may be underestimated. The increasing use of whole genome sequencing in diagnostic settings will help to get a more comprehensive view of retrogenes.

Angiographic characteristics and treatment approach in patients undergoing intra-arterial chemotherapy for retinoblastoma.

PURPOSE: To identify the specific clinical and angiographic variables that determine the success of intra-arterial chemotherapy (IAC) in a patient with retinoblastoma. METHODS: Medical records from patients undergoing intra-arterial chemotherapy for the treatment of retinoblastoma between January 2015 and June 2020 within a large academic ocular oncology practice were retrospectively reviewed. Demographics were recorded together with clinical, ocular, and angiographic variables such as the diameter of the ophthalmic artery (OA), angle of ophthalmic artery takeoff, and branching pattern of ophthalmic vasculature. RESULTS: Forty-four eyes from 33 patients with retinoblastoma treated with IAC were identified. Over the total 32 mean months of follow-up, these patients received 144 total catheterizations and a mean of 3.2 IAC cycles for each eye. The number of IAC cycles and the chemotherapeutic agent used did not vary significantly with worsening International Classification of Retinoblastoma (ICRB) groups (P > 0.1). Cumulative dose did not vary with the ICRB group for eyes treated with melphalan, topotecan, or carboplatin (P > 0.1). A higher ICRB group was associated with a smaller mean ophthalmic artery diameter across all procedures (P = 0.016), and femoral artery diameter did not vary significantly between ICRB groups (P = 0.906). A higher cumulative dose of IAC was significantly associated with a smaller takeoff angle of the OA (melphalan, P = 0.011; topotecan, P = 0.009; carboplatin, P = 0.031) in patients who underwent successful IAC procedures. Ophthalmic artery diameter and femoral artery diameter did not have a significant association (P > 0.1) with higher IAC doses in successful IACs. Cumulative IAC dose was not significantly associated with ophthalmic vasculature branching pattern, presence of choroidal blush, temporary OA vasospasm reported during the procedure, and OA occlusion upon microcatheter placement. CONCLUSION: In this study, neurosurgical angioanatomy appeared to influence the cumulative dose of chemotherapy needed during IAC for retinoblastoma. In the future, these anatomic variables may be used to guide the frequency of monitoring, dosing, and estimation of recurrence risk.

INTRAVITREAL MELPHALAN INJECTION AS A SECOND-LINE LOCAL THERAPY IN VITREORETINAL LYMPHOMA: Case Series.

PURPOSE: To evaluate the effectiveness and safety of intravitreal melphalan (IVM) injection therapy in vitreoretinal lymphoma. METHODS: Eight eyes of five biopsy-proven vitreoretinal lymphoma patients who were treated with IVM injection as a second-line therapy after intravitreal methotrexate and rituximab injections were retrospectively evaluated between January 2011 and March 2023. RESULTS: The medical records of five vitreoretinal lymphoma patients (mean age of 62 years at the diagnosis) including 4 (80%) female patients and 1 (20%) male patient were retrospectively analyzed. Three patients (60%) either had a history of central nervous lymphoma or developed it during the follow-up. Patients were previously treated with a mean of five cycles of monthly intravitreal methotrexate and rituximab injections. All eyes showed complete response by the disappearance of vitreal and/or subretinal neoplastic cells within 6 weeks after IVM injections (range, 1-4 injections per eye). Of 12 IVM injections, 3 (25%) injections were associated with macular edema diagnosed on optical coherence tomography at 1-month follow-up and resolved spontaneously within 5 months. The IVM administration induced new retinal pigment epithelium changes in three eyes (37%). CONCLUSION: Intravitreal melphalan injection may be effective in the management of vitreoretinal lymphoma as a second-line local therapy. Randomized clinical trials with larger numbers of patients are needed to establish the efficacy, treatment protocol, and safety of IVM injection.

Optical coherence tomography features in vitreoretinal lymphoma compared with non-infectious uveitis.

BACKGROUND: Vitreoretinal lymphoma (VRL) is a rare intraocular malignancy that poses a diagnostic challenge due to the non-specific clinical presentation that resembles uveitis. The use of spectral domain optical coherence tomography (SD-OCT) has emerged as a valuable imaging tool to characterize VRL. Therefore, we sought to determine the specific OCT features in VRL compared to the uveitides. METHODS: Retrospective chart review of patients who were seen at Mayo Clinic from January 1, 2010 through December 31, 2022. The medical records and SD-OCT images at time of initial presentation were reviewed in patients with biopsy-proven VRL, intermediate uveitis, or biopsy-confirmed sarcoid posterior uveitis. Patients with VRL or similar uveitides including intermediate uveitis or sarcoid posterior uveitis were included. RESULTS: There were 95 eyes of 56 patients in the VRL group and 86 eyes of 45 patients in the uveitis group, of whom 15 (33.3%) were diagnosed with intermediate uveitis and 30 (66.7%) with sarcoid chorioretinitis. The SD-OCT features more commonly seen at initial presentation in VRL patients (vs. uveitis) included preretinal deposits (31.6% vs. 9.3%, p = 0.002), intraretinal infiltrates (34% vs. 3.5%, p < 0.001), inner retinal hyperreflective spots (15.8% vs. 0%, p < 0.001), outer retinal atrophy (22.1% vs. 2.3%, p < 0.001), subretinal focal deposits (21.1% vs. 4.7%, p = 0.001), retinal pigmented epithelium (RPE) changes (49.5% vs. 3.5%, p < 0.001), and sub-RPE deposits (34.7% vs. 0%, p < 0.001). Features more frequently seen in uveitis included epiretinal membrane (ERM) (82.6% vs. 44.2%, p < 0.001), central macular thickening (95.3% vs. 51.6%, p < 0.001), cystoid macular edema (36% vs. 11.7%, p < 0.001), subretinal fluid (16.3% vs 6.4%, p = 0.04), and subfoveal fluid (16.3% vs. 3.2%, p = 0.003). Multivariate regression analysis controlling for age and sex showed absence of ERM (OR 0.14 [0.04,0.41], p < 0.001) and absence of central macular thickening (OR 0.03 [0,0.15], p = 0.02) were associated with VRL as opposed to uveitis. CONCLUSION: OCT features most predictive of VRL (vs. uveitis) included absence of ERM and central macular thickening.

Swept-source optical coherence tomography angiography findings in a case of primary vitreoretinal lymphoma over a three-year follow-up.

BACKGROUND: Vitreoretinal lymphoma (VRL) still represents a diagnostic challenge for retinal specialists. Early diagnosis and treatment are critical for a better prognosis. Several diagnostic tools have proven helpful in the identification of VRL abnormalities. However, swept-source OCT angiography (SS-OCT-A) findings and their long-term follow-up are yet to be explored. CASE PRESENTATION: a 42-year-old man presented with blurred vision in his left eye for 2 weeks. He denied any systemic symptoms. A multimodal imaging examination was performed, raising the clinical suspicion of VRL and guiding the ensuing diagnostic procedures. The patient underwent treatment and at the last FU visit three years later, no disease signs were present on fundus examination, nor on oncologic evaluation. Some novel SS-OCT-A features were identified, and uncommonly reported findings were examined over a long-term follow-up. At baseline multiple hyperreflective alterations were detected on the enface outer retina slabs and choriocapillary analysis revealed low reflectance areas in the foveal and parafoveal areas. One month after the first presentation, multiple hyperreflective retinal lesions in a vertical shape were detected on OCT which appeared on midretinal slabs of enface SS-OCT-A as hyperreflective spots mainly located near second-order retinal vessels. These alterations remarkably reduced after treatment. CONCLUSION: SS-OCT-A may be a useful imaging technique in the detection of VRL, providing ophthalmologists additional findings that assist the diagnosis and follow-up of this disease. This may prove useful for a more timely and precise diagnosis, prompt therapy, and treatment response monitoring. The original aspects found in this case may provide grounds for future studies, ultimately fostering a better understanding of the disease.

When the second comes first- rhabdomyosarcoma preceding heritable retinoblastoma- a case report.

BACKGROUND: Retinoblastoma (rb) is the most frequent intraocular tumor, accounting for 3% of all childhood cancers. Heritable rb survivors are germline carriers for an RB1 mutation and have a lifelong risk to develop non-ocular second primary tumors (SPTs) involving multiple other organs like the bones, soft tissues, or skin. These SPTs usually become manifest several years succeeding the diagnosis of rb. In our instance, however, a non-ocular SPT presented prior to the diagnosis of heritable rb. CASE PRESENTATION: We report a rare case of a monozygotic twin who presented with primary rhabdomyosarcoma (RMS) preceding the manifestation of heritable rb. The rb was diagnosed when the child developed strabismus while already on therapy for the RMS. The child underwent therapy for both as per defined treatment protocols. The rb regressed well on treatment, but the RMS relapsed and the child developed multiple refractory metastatic foci and succumbed to his disease. CONCLUSIONS: Non-ocular SPTs like sarcomas are usually known to manifest in heritable rb survivors with a lag of two to three decades (earlier if exposure to radiation is present) from the presentation of the rb. However, in our case, this seemed to be reversed with the RMS being manifest at an unusual early age and the rb being diagnosed at a later point in time.

Global retinoblastoma studies: A review.

In the current era of global health awareness for retinoblastoma (RB), the challenge that lies ahead of us is providing optimal care for children affected with RB in underdeveloped nations. The understanding of similarities and disparities between various nations across the world aids in achieving comparable outcomes. With dissolving geographic barriers and evolving collaboration, global collaborative studies on RB are becoming increasingly common. They provide real-world, robust evidence on several aspects of RB. This review discusses insights gained from global RB studies regarding the demographics, certain aspects of etiopathogenesis and epidemiology, international travel burden, disparities in clinical presentations based on national income levels, management protocols, pathology, treatment outcomes, and the effect of COVID-19 on RB care across the world. These insights are likely to impact individual practice as well as inform policy reforms.

Low expression of NR1D1 and NR2E3 is associated with advanced features of retinoblastoma.

PURPOSE: To investigate the expression of nuclear receptor subfamily 1 group D member 1 (NR1D1) and nuclear receptor subfamily 2 group E Member 3 (NR2E3) in retinoblastoma (RB) and their correlation with the clinical and pathological features of RB. METHODS: Immunohistochemical (IHC) assays were performed to detect and evaluate the expression levels of NR1D1 and NR2E3 in paraffin-embedded tissue samples. The relationship between the expression levels and clinicopathological characteristics of RB patients was analyzed using the χ2 test or Fisher exact test. RESULTS: A total of 51 RB patients were involved in this research. The expression levels of NR1D1 (P = 0.004) and NR2E3 (P = 0.024) were significantly lower in RB tumor tissues than in normal retina. The expression levels of NR1D1 and NR2E3 were less positive in RB patients with advanced stages (P = 0.007, P = 0.015), choroidal infiltration (P = 0.003, P = 0.029), and optic nerve infiltration (P = 0.036, P = 0.003). In addition, a low expression level of NR2E3 was associated with high-risk pathology (P = 0.025) and necrosis (P = 0.035) of RB tissues. CONCLUSION: The expression levels of NR1D1 and NR2E3 were decreased in RB and closely associated with the clinical stage and high invasion of the disease. These findings provide new insights into the mechanism of RB progression and suggest that NR1D1 and NR2E3 could be potential targets for treatment strategies.

[Isolated primary vitreoretinal lymphoma (case report)]. / Izolirovannaya pervichnaya vitreoretinal'naya limfoma (klinicheskoe nablyudenie).

This case report presents the diagnostic features of isolated primary intraocular lymphoma, which was initially misdiagnosed as neovascular age-related macular degeneration. A comprehensive examination using ultrasound, optical coherence tomography, and fundus autofluorescence revealed changes characteristic of vitreoretinal lymphoma. Molecular genetic analysis of the vitreous body showed the presence of a MYD88 gene mutation and B-cell clonality by immunoglobulin heavy chain (IGH) gene rearrangement tests, which confirmed the diagnosis.

Automatic retinoblastoma screening and surveillance using deep learning.

BACKGROUND: Retinoblastoma is the most common intraocular malignancy in childhood. With the advanced management strategy, the globe salvage and overall survival have significantly improved, which proposes subsequent challenges regarding long-term surveillance and offspring screening. This study aimed to apply a deep learning algorithm to reduce the burden of follow-up and offspring screening. METHODS: This cohort study includes retinoblastoma patients who visited Beijing Tongren Hospital from March 2018 to January 2022 for deep learning algorism development. Clinical-suspected and treated retinoblastoma patients from February 2022 to June 2022 were prospectively collected for prospective validation. Images from the posterior pole and peripheral retina were collected, and reference standards were made according to the consensus of the multidisciplinary management team. A deep learning algorithm was trained to identify "normal fundus", "stable retinoblastoma" in which specific treatment is not required, and "active retinoblastoma" in which specific treatment is required. The performance of each classifier included sensitivity, specificity, accuracy, and cost-utility. RESULTS: A total of 36,623 images were included for developing the Deep Learning Assistant for Retinoblastoma Monitoring (DLA-RB) algorithm. In internal fivefold cross-validation, DLA-RB achieved an area under curve (AUC) of 0.998 (95% confidence interval [CI] 0.986-1.000) in distinguishing normal fundus and active retinoblastoma, and 0.940 (95% CI 0.851-0.996) in distinguishing stable and active retinoblastoma. From February 2022 to June 2022, 139 eyes of 103 patients were prospectively collected. In identifying active retinoblastoma tumours from all clinical-suspected patients and active retinoblastoma from all treated retinoblastoma patients, the AUC of DLA-RB reached 0.991 (95% CI 0.970-1.000), and 0.962 (95% CI 0.915-1.000), respectively. The combination between ophthalmologists and DLA-RB significantly improved the accuracy of competent ophthalmologists and residents regarding both binary tasks. Cost-utility analysis revealed DLA-RB-based diagnosis mode is cost-effective in both retinoblastoma diagnosis and active retinoblastoma identification. CONCLUSIONS: DLA-RB achieved high accuracy and sensitivity in identifying active retinoblastoma from the normal and stable retinoblastoma fundus. It can be used to surveil the activity of retinoblastoma during follow-up and screen high-risk offspring. Compared with referral procedures to ophthalmologic centres, DLA-RB-based screening and surveillance is cost-effective and can be incorporated within telemedicine programs. CLINICAL TRIAL REGISTRATION: This study was registered on ClinicalTrials.gov (NCT05308043).

Patient-derived xenograft mouse models to investigate tropism to the central nervous system and retina of primary and secondary central nervous system lymphoma.

AIMS: How and why lymphoma cells home to the central nervous system and vitreoretinal compartment in primary diffuse large B-cell lymphoma of the central nervous system remain unknown. Our aim was to create an in vivo model to study lymphoma cell tropism to the central nervous system. METHODS: We established a patient-derived central nervous system lymphoma xenograft mouse model and characterised xenografts derived from four primary and four secondary central nervous system lymphoma patients using immunohistochemistry, flow cytometry and nucleic acid sequencing technology. In reimplantation experiments, we analysed dissemination patterns of orthotopic and heterotopic xenografts and performed RNA sequencing of different involved organs to detect differences at the transcriptome level. RESULTS: We found that xenografted primary central nervous system lymphoma cells home to the central nervous system and eye after intrasplenic transplantation, mimicking central nervous system and primary vitreoretinal lymphoma pathology, respectively. Transcriptomic analysis revealed distinct signatures for lymphoma cells in the brain in comparison to the spleen as well as a small overlap of commonly regulated genes in both primary and secondary central nervous system lymphoma. CONCLUSION: This in vivo tumour model preserves key features of primary and secondary central nervous system lymphoma and can be used to explore critical pathways for the central nervous system and retinal tropism with the goal to find new targets for novel therapeutic approaches.

Primary vitreoretinal lymphoma: a diagnostic and management challenge.

Primary vitreoretinal lymphoma (PVRL) is a rare form of primary central nervous system (CNS) lymphoma (PCNSL) arising in the intraocular compartment without brain involvement. Despite its apparent indolent clinical course, PVRL can cause permanent vision loss and CNS relapse, the major cause of death in patients with PVRL. The pathophysiology of PVRL is unknown. As in PCNSL, the transformation of the tumor cells likely originates outside the CNS, before the cells migrate to the eye and proliferate within an immune-permissive microenvironment. PVRL exhibits a biased immunoglobulin repertoire, suggesting underlying antigen selection. The diagnosis remains challenging, requiring close coordination between ophthalmologists and cytologists. Because of their rarity and fragility in the vitreous, lymphoma cells cannot always be identified. Interleukin levels, molecular biology, and imaging are used in combination with clinical ophthalmological examination to support the diagnosis of PVRL. Multi-institutional prospective studies are urgently needed to validate the equivocal conclusions regarding treatments drawn from heterogeneous retrospective or small cohort studies. Intravitreal injection of methotrexate or rituximab or local radiotherapy is effective at clearing tumor cells within the eyes but does not prevent CNS relapse. Systemic treatment based on high-dose methotrexate chemotherapy, with or without local treatment, might reduce this risk. At relapse, intensive consolidation chemotherapy followed by stem cell transplantation can be considered. Single-agent ibrutinib, lenalidomide, and temozolomide treatments are effective in patients with relapsed PVRL and should be tested as first-line treatments. Therapeutic response assessment based on clinical examination is improved by measuring cytokine levels but still needs to be refined.

Retinoblastoma: present scenario and future challenges.

With an average incidence of 1 in every 18,000 live births, retinoblastoma is a rare type of intraocular tumour found to affect patients during their early childhood. It is curable if diagnosed at earlier stages but can become life-threateningly malignant if not treated timely. With no racial or gender predisposition, or even environmental factors known to have been involved in the incidence of the disease, retinoblastoma is often considered a clinical success story in pediatric oncology. The survival rate in highly developed countries is higher than 95% and they have achieved this because of the advancement in the development of diagnostics and treatment techniques. This includes developing the already existing techniques like chemotherapy and embarking on new strategies like enucleation, thermotherapy, cryotherapy, etc. Early diagnosis, studies on the etiopathogenesis and genetics of the disease are the need of the hour for improving the survival rates. According to the Knudson hypothesis, also known as the two hit hypothesis, two hits on the retinoblastoma susceptibility (RB) gene is often considered as the initiating event in the development of the disease. Studies on the molecular basis of the disease have also led to deciphering the downstream events and thus in the discovery of biomarkers and related targeted therapies. Furthermore, improvements in molecular biology techniques enhanced the development of efficient methods for early diagnosis, genetic counseling, and prevention of the disease. In this review, we discuss the genetic and molecular features of retinoblastoma with a special emphasis on the mutation leading to the dysregulation of key signaling pathways involved in cell proliferation, DNA repair, and cellular plasticity. Also, we describe the classification, clinical and epidemiological relevance of the disease, with an emphasis on both the traditional and innovative treatments to tackle retinoblastoma. Video Abstract.

Tandem high-dose chemotherapy followed by autologous stem cell transplantation: An infant with trilateral retinoblastoma.

BACKGROUND: Retinoblastoma (RB) is the most common intraocular malignancy in childhood. Advanced RB, associated with exceedingly poor prognosis, requires more intensive multiagent chemotherapy than conventional regimens. Rescue of the bone marrow after intensive chemotherapy is achieved with stem cell transplantation. The sequential courses (tandem transplantation) of high-dose chemotherapy followed by autologous stem cell transplantation allow for even greater dose intensity in consolidation with the potential to use different active chemotherapeutics at each transplant and have proven feasible and successful in treating children with recurrent/refractory solid tumors. CASE DESCRIPTION: We report an infant with trilateral high-risk RB who received tandem high-dose chemotherapy (HDC) followed by autologous stem cell transplantation after the conventional chemotherapy. A 5-month-old female patient presented with strabismus, and the ophthalmoscopic examination showed intraocular tumoral lesions in both eyes. Magnetic resonance imaging (MRI) concluded the trilateral retinoblastoma diagnosis due to a tumoral mass in the optic chiasm. The follow-up ophthalmologic examinations and the MRI detected stable disease after six cycles of multiagent chemotherapy. CONCLUSIONS: Rescue with autologous stem cell transplantation after HDC allows for an increase in chemotherapy intensity. Tandem transplantation provides the chance to perform different chemotherapeutics at each transplant and enables an increase in the chemotherapy intensity, thus providing a positive effect on disease-free survival.

A novel de-novo RB1 mutation identified in a patient with bilateral retinoblastoma.

Retinoblastoma manifests as ocular malignancy due to mutations in the RB1 gene. A 17-month-old girl with bilateral retinoblastoma having no family history was admitted to our hospital. The right eye was enucleated but the other was preserved with systemic chemotherapy and topical treatment. The patient has been tumor-free for over 7 years since diagnosis. All exons of RB1 were sequenced and a novel 1-base pair deletion (NM_000321.2:c.2409del, p.Asn803Lysfs*7) was detected.

Comparing internal versus external carotid artery branch delivery of intraarterial chemotherapy for the treatment of retinoblastoma.

PURPOSE: The goal of this study was to compare the efficacy of intraarterial chemotherapy (IAC) for retinoblastoma delivered via the ophthalmic artery (OA) division of the internal carotid artery (ICA) versus alternative branches of the external carotid artery (ECA). METHODS: We performed a retrospective chart review of patients receiving IAC for retinoblastoma at a single institution. Subjects were divided into three groups: those that received IAC solely through the OA branch of the ICA, those that initially received IAC through the OA branch of the ICA but were later switched to the ECA, and those that only received IAC through the ECA. The main outcomes compared included globe salvage rate and reduction in tumor thickness and size. RESULTS: A total of 30 eyes from 26 patients were included. A total of 91 (58%) sessions of IAC were performed through the OA division of the ICA and 65 (42%) were performed through branches of the ECA. Eleven eyes (37%) solely received IAC through the OA branch of the ICA, 16 eyes (53%) were converted to ECA treatment, and 3 eyes solely received IAC through branches of the ECA. Statistical analysis did not show any significant difference in globe salvage rate or reduction in tumor thickness and size. CONCLUSION: The use of alternative approaches for IAC when the OA branch of the ICA catheterization is not feasible allows for safe continued delivery of highly effective IAC, leading to similar outcomes in terms of globe salvage and reduction in tumor size.