Treatment Of Retinoblastoma Research Articles

RNA Sequencing and Bioinformatic Analysis on Retinoblastoma Revealing that Cell Cycle Deregulation Is a Key Process in Retinoblastoma Tumorigenesis

Purpose: Retinoblastoma (RB) is a primary pediatric ocular malignancy that can be fatal with inadequate treatment. While multimodal treatments are applied for eye salvage, vision loss and metastasis can occur in some patients. The present study aimed to explore key pathways and factors in RB pathogenesis, which could be potential targets for novel RB treatments. Methods: RNA sequencing was performed on three RB tissues and referenced with three normal retinas. Differentially expressed genes (DEGs) were identified from sequencing data and further analyzed with clustering analysis, function and pathway enrichment, protein-protein interaction (PPI), and data-mining analysis in order to screen for tumorigenic relevancy. Results: A total of 331 DEGs were identified by clustering analysis of RB tissues, and the expression patterns were significantly distinguishable from normal retinas. Function and pathway enrichment and PPI analysis together showed that cell cycle was the most prominently upregulated pathway found in RB tissues. Following comprehensive bioinformatic analyses, six key genes relevant to cell cycle regulation were identified, namely BUB1, RRM2, TPX2, UBE2C, NUSAP1, and DTL. Conclusions: Cell cycle pathway and six relevant genes may be potential key factors in RB tumorigenesis and laying the foundation for prospective investigation on development of novel targeted therapies.

Global Retinoblastoma Presentation and Analysis by National Income Level

Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs.

Combined intra-arterial chemotherapy and intravitreal melphalan for the treatment of advanced unilateral retinoblastoma.

To evaluate the efficacy and safety of combined intra-arterial chemotherapy (IAC) and intravitreal melphalan (IVM) for the treatment of advanced unilateral retinoblastoma. This retrospective study involved 30 consecutive eyes from 30 Chinese patients with advanced unilateral retinoblastoma. All patients were initially treated with IAC combined with IVM. The clinical status and complications were recorded at each visit. The International Intraocular Retinoblastoma Classification groups were D in 23 eyes and E in 7 eyes. All eyes showed severe cloud vitreous seeds at the first visit. The mean number of IAC cycles and intravitreal injections was 3.2 (range, 3-4) and 6 (range, 1-14), respectively. The median follow-up time was 29mo (range, 7-36mo). Treatment success with regression of the retinal tumor and vitreous seeds was achieved in 29 of 30 eyes (96.7%). Globe salvage was attained in 93.3% (28/30) eyes, and enucleation (n=2) was performed due to neovascular glaucoma and persistent vitreous hemorrhage. Complications included retinal pigment epithelium (RPE) atrophy (n=13; 43%), mild lens opacity (n=7; 23%), vitreous hemorrhage (n=5; 17%) and rhegmatogenous retinal detachment (n=1; 3%). No extraocular tumor extension or metastasis occurred. Combined IAC and IVM is effective and safe for the treatment of advanced unilateral retinoblastoma.

Intravitreal melphalan therapy for vitreous seeds in retinoblastoma: Implementation and outcomes of a new chemotherapy protocol.

Retinoblastoma is the most common paediatric ocular tumour, which appears in the retina. Without treatment, retinoblastoma grows and destroys the internal ocular globe architecture, even leading to metastasis. When treated, overall survival is close to 97%, the alkylating drug melphalan being the most extensively used chemotherapeutic agent in localised treatment. The aim of this study is to describe the implementation of a new intravitreal chemotherapy retinoblastoma treatment protocol for children implanting vitreous seeds through intravitreal melphalan injections and to evaluate the patients' health outcomes treated with it. Between December 2014 and July 2018, seven patients were treated with this protocol. They received a mean of 3.3 cycles of intravitreal melphalan with standard doses of 30 mcg per cycle. In the seven eyes treated in our hospital, the response was as expected; three eyes with vitreous seedings (43%) were successfully treated. The main adverse effects presented by all patients were scars at cryogenisation points. In two patients, the appearance of 'salt and pepper' retinopathy was reported. Oncology pharmacists, as part of the treatment team, can provide information about recommended doses, expected adverse effects, stability of preparations, most appropriate method of processing, packaging, and methods of drug administration, to ensure efficacy and especially safety in the administration of these drugs.

Abstract TP55: The Use of Alternative Routes for the Delivery of Intra-Arterial Chemotherapy for Retinoblastoma

Background: The introduction of intra-arterial chemotherapy (IAC) for treatment of retinoblastoma considerably changed the paradigm by which this disease is managed, with event-free survival rates being above 70%. Objective: Our aim is to analyze efficacy of IAC treatment using alternative approaches to OAC such as external carotid artery (ECA) approach or balloon-assisted drug delivery. Methods: This is a retrospective chart review for subjects receiving IAC for retinoblastoma. The primary approach was OAC. In cases where selective OAC was not feasible, alternative routes including catheterization of the ECA or use of a balloon-assisted drug infusion where used. Results: This study included 197 consecutive patients with 207 retinoblastomas who underwent 658 IAC procedures overall. The mean age at diagnosis was 24 months, and 54.5% of the study population was male. Success rate with IAC was 97% (639. Alternative approaches to OAC were in total 42 cases (6.4%) - external carotid artery catheterization and use of ICA balloon were performed in 22 (3.3%) and 20 (3%) cases respectively. A mean of 3.1 IAC cycles were performed for each patient. In total, 23 technical failures of the primary OAC technique (3.4%). Periprocedural adverse events occurred in 4 procedures (0.6%). Use of an alternative technique for chemotherapy delivery other than selective OAC in at least one IAC cycle was not a predictor of enucleation. Conclusions: IAC is a safe and effective treatment option for retinoblastoma. Chemotherapy delivery using alternative techniques is as effective as selective OAC.

Pars plana vitrectomy under melphalan irrigation for recurrent retinal detachment in eyes treated for retinoblastoma: a case report

BackgroundTractional retinal detachment with or without secondary tear is a rare complication reported in less than 0.5% of in eyes treated for retinoblastoma. Pars plana vitrectomy (PPV) in eyes with history of retinoblastoma has been associated with a significant risk for recurrence, extraocular spread, and systemic metastases. We report here the successful management by PPV under melphalan irrigation of 2 children presenting with tractional retinal detachment after retinoblastoma therapy and scleral buckle surgery.Case presentationA 7-year-old girl with a history of bilateral retinoblastoma (group D) presented with light perception best-corrected visual acuity (BCVA) and tractional retinal detachment (RD) in her left eye, 3 years after the last intra-arterial chemotherapy (IAC) injection. Moreover, she had history of left eye rhegmatogenous RD treated by scleral buckle 1 month after the last IAC and cataract surgery 12 months later. PPV associated with retinectomy, laser photocoagulation and silicone oil tamponade was performed. Silicone oil was removed 4 months later. Fifteen months after PPV, BCVA had increased to 20/32 without recurrence of RD and no evidence of tumor activity. A 7-year-old boy with a history of unilateral retinoblastoma (group D) in his left eye presented with rhegmatogenous RD 21 months after the last treatment for retinoblastoma. Scleral buckle surgery was performed, but 3 weeks later the patient presented with tractional RD associated with proliferative vitreo-retinopathy. BCVA was counting fingers. PPV associated with membrane peel, laser photocoagulation and silicone oil tamponade was performed. Silicone oil was removed after 5 months followed by cataract surgery 5 months later. Twenty months after PPV, BCVA was 20/20 and there was no sign of tumor recurrence.ConclusionsPPV under melphalan irrigation, with retinectomy, if necessary, and silicone oil tamponade, allows anatomical and functional improvement in eyes with history of retinoblastoma and scleral buckling developing tractional RD.

The Role of Intraarterial Chemotherapy in the Management of Retinoblastoma.

Introduction. Retinoblastoma is the most common primary intraocular neoplasm in children. With the advances in medicine, the armamentarium of available treatment modalities has grown. Intraarterial chemotherapy is a relatively new treatment method with promising outcomes. The purpose of this literature review is to evaluate its role in the management of retinoblastoma. Methods A systematic online search was conducted using Ovid Embase and Ovid Medline. The final results included 23 studies. The studies were published between 2011 and 2019. The studies evaluated the technical success rate of IAC, globe salvage rate, and ocular and systemic complications, as well as the occurrence of deaths, metastasis, and secondary neoplasms. In total, 1827 eyes with retinoblastoma were analysed. The follow-up was between 0 and 252 months. Results Overall globe retention rate ranged from 30% to 100%. Sixteen out of 23 studies reported ocular salvage between 60 and 80%. Eyelid oedema and erythema were the most commonly reported ocular complications following IAC. The most common systemic complications included nausea, vomiting, and neutropenia. Metastases and deaths were reported in 6 out of 23 studies. Three studies reported the development of secondary neoplasms. The technical success rate of IAC procedure ranged from 91% to 100%. Discussion. The studies have shown that IAC is a safe and effective treatment for advanced retinoblastoma, especially group D. It allows to save the globe without compromising patients' survival. Local and systemic complications are acceptable. The role of IAC in less advanced tumours is yet to be established. Future work should focus on conducting larger prospective studies with longer follow-up. Multiple novel therapies for the management of retinoblastoma are currently being tested, including angiogenic inhibitors and targeted agents. The results seem to be promising. Future advances require a further in-depth understanding of unique genetics of retinoblastoma and complex interactions between tumour cells and their microenvironment.

Multifunctional Nanoparticles for Multimodal Imaging-Guided Low-Intensity Focused Ultrasound/Immunosynergistic Retinoblastoma Therapy.

Retinoblastoma (RB) is prone to delayed diagnosis or treatment and has an increased likelihood of metastasizing. Thus, it is crucial to perform an effective imaging examination and provide optimal treatment of RB to prevent metastasis. Nanoparticles that support diagnostic imaging and targeted therapy are expected to noninvasively integrate tumor diagnosis and treatment. Herein, we report a multifunctional nanoparticle for multimodal imaging-guided low-intensity focused ultrasound (LIFU)/immunosynergistic RB therapy. Magnetic hollow mesoporous gold nanocages (AuNCs) conjugated with Fe3O4 nanoparticles (AuNCs-Fe3O4) were prepared to encapsulate muramyl dipeptide (MDP) and perfluoropentane (PFP). The multimodal imaging capabilities, antitumor effects, and dendritic cell (DC) activation capacity of these nanoparticles combined with LIFU were explored in vitro and in vivo. The biosafety of AuNCs-Fe3O4/MDP/PFP was also evaluated systematically. The multifunctional magnetic nanoparticles enhanced photoacoustic (PA), ultrasound (US), and magnetic resonance (MR) imaging in vivo and in vitro, which was helpful for diagnosis and efficacy evaluation. Upon accumulation in tumors via a magnetic field, the nanoparticles underwent phase transition under LIFU irradiation and MDP was released. A combined effect of AuNCs-Fe3O4/MDP/PFP and LIFU was recorded and verified. AuNCs-Fe3O4/MDP/PFP enhanced the therapeutic effect of LIFU and led to direct apoptosis/necrosis of tumors, while MDP promoted DC maturation and activation and activated the ability of DCs to recognize and clear tumor cells. By enhancing PA/US/MR imaging and inhibiting tumor growth, the multifunctional AuNC-Fe3O4/MDP/PFP nanoparticles show great potential for multimodal imaging-guided LIFU/immunosynergistic therapy of RB. The proposed nanoplatform facilitates cancer theranostics with high biosafety.

Craniofacial second primary tumors in patients with germline retinoblastoma previously treated with external beam radiotherapy: A retrospective institutional analysis.

The long-term survival of germline retinoblastoma patients is decreased due to the risk of second primary tumors (SPTs) that occur years after the diagnosis of retinoblastoma. This risk is related to genetic predisposition and other factors, such as the treatment of retinoblastoma by external beam radiotherapy (EBRT). We studied the incidence, risk factors, and prognosis of specific craniofacial SPTs developed within the margins of radiation field in a cohort of 209 patients with germline retinoblastoma treated with EBRT at our institution between 1977 and 2010. Clinical characteristics, survival, incidence, and histology of craniofacial SPTs were recorded. Fifty-three of the 209 patients developed 60 distinct craniofacial SPTs in irradiated field with a median time from EBRT of 16.9 years (4-35) and a median follow-up of 24.8 years (5.3-40). Osteosarcoma (33.3%) and undifferentiated sarcoma (23.3%) were the more prevalent histological entities. Benign tumors (16.7%) also occurred. The cumulative incidence of craniofacial SPTs reached 32.6% at 35 years after EBRT, and the median survival after diagnosis was five years. In our series, irradiation under 12 months of age, bilateral EBRT, or previous treatment of retinoblastoma with chemotherapy did not significantly increase the risk of craniofacial SPTs. This work presents a strong argument to avoid EBRT in the management of retinoblastoma and emphasizes the high risk and poor prognosis of specific craniofacial SPTs. This study also points to the question of the need and benefits of special programs for early detection of craniofacial SPTs in survivors of irradiated germline retinoblastoma.

Role of Mitochondria and Lysosomes in the Selective Cytotoxicity of Cold Atmospheric Plasma on Retinoblastoma Cells.

Retinoblastoma (RB) is a common malignancy in childhood, with an incidence of 1 per 20,000 live births. Several approaches such as chemotherapy, laser, and radiotherapy have been used for the treatment of RB. However, the effectiveness of these methods is not sufficient and the mechanisms involved in the pathogenesis of the disease are not well understood. The disruption of the apoptotic process is considered as one of the mechanisms involved in the pathogenesis of RB. This study was designed to examine the in-vitro selective toxicity of cold atmospheric plasma (CAP) on RB cells’ mitochondria and lysosomes. The results showed that CAP decreased cell viability and GSH content and also increased caspase-3 activity and lipid peroxidation (LPO) in cancerous ocular cells isolated from the rat model of RB compared to the normal rat ocular cells. Furthermore, results demonstrated that CAP significantly increased ROS generation, mitochondrial membrane potential (MMP) collapse, mitochondrial swelling, and cytochrome c release only in cancerous rat ocular mitochondria but not the normal rat ocular mitochondria. Furthermore, our results demonstrated that CAP significantly increased the lysosomal damage only in the cancer group. Altogether, the results of the study showed that CAP could selectively induce apoptosis on RB mitochondria. CAP may therefore be considered as a promising candidate for further in-vivo and clinical researches to reach a new anti- RB drug.

Clinicopathologic evaluation of primary vs secondary enucleated unilateral group D retinoblastoma eyes

Background The risk of tumor spread is the main concern while deciding primary treatment in advanced unilateral retinoblastoma, which presents later with an intact normal eye. Enucleation was recommended as a radical treatment but with newer treatment options such as systemic and intra-arterial chemotherapy. Ocular salvage could be tried in group D eyes with smaller tumors and visual potential. Aim The aim was to assess the histopathologic metastatic risk in primary vs secondary enucleated (trial salvage) unilateral group D eyes. Design Retrospective, noncomparative, single-institution observational case series. Patients and methods All primary and secondary enucleated unilateral group D eyes (June 2012 to December 2018) managed at the pediatric ocular oncology unit, Ophthalmology Department, University of Alexandria. Clinical, radiological, histopathologic, and treatment data were collected. Clinicopathologic correlation was performed to identify the frequency of high-risk histopathologic features (HRHF). Statistical analysis All analyses were performed using Microsoft Excel 2013 software and SPSS software version 17.0. Results Twenty-six eyes were included. Sixteen were primary enucleated and none showed HRHF while 10 were secondary enucleated after failed trial salvage. Timely enucleated secondary cases (6/10) showed no HRHF while delayed secondary enucleation (2/4) was significantly associated with HRHF (P=0.02). All cases are alive with no metastasis after a median follow-up of 5 years. Conclusion Primary and timely secondary enucleation for unilateral group D retinoblastoma eyes are comparable in low metastatic risk and effectivity of tumor control. Controlled discussed trial ocular salvage is safe conditioned by strict timely termination, if necessary.

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.

MiR-214-3p Regulates Multi-Drug Resistance and Apoptosis in Retinoblastoma Cells by Targeting ABCB1 and XIAP.

BackgroundMicroRNAs (miRNAs) have been shown to contribute to the initiation and progression of human cancer, including retinoblastoma. However, expression levels and potential roles of miRNAs in retinoblastoma remain largely unknown. In this study, we aimed to identify dysregulated miRNAs and explore their functional roles in the development of retinoblastoma.Material and MethodsFirst, miRNA expression profiling in retinoblastoma tissues was performed via microarray analysis. To evaluate the involvement of miR-214-3p in multi-drug resistance, gain-of-function experiments were employed in vitro and in vivo. Bioinformatics analysis, luciferase reporter assay, qRT-PCR and Western blot were used to investigate the underlying mechanisms.ResultsHere, we identified 57 up-regulated and 34 down-regulated miRNAs. Among them, miR-214-3p was the most significantly decreased. We found that miR-214-3p level was positively correlated with clinical outcome and chemotherapy response. Overexpression of miR-214-3p significantly sensitized retinoblastoma cells to multiple chemodrugs and promoted cell apoptosis in vitro and in vivo. Further investigations revealed that miR-214-3p directly regulated ABCB1 and XIAP expression through interacting with the 3’ untranslated regions (3’UTRs). Pearson correlation analysis showed that miR-214-3p expression in retinoblastoma tissues was negatively correlated with ABCB1 and XIAP expression. We also observed that overexpression of ABCB1 or XIAP partly reversed the chemoresistance inhibition-induced by miR-214-3p overexpression.ConclusionOur data demonstrate that miR-214-3p functions as a tumor suppressor to inhibit the chemoresistance in retinoblastoma, suggesting that miR-214-3p might be potential diagnostic and therapeutic targets for retinoblastoma treatment.

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

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

EXPERIMENTAL IMMUNOTHERAPY MODEL OF RETINOBLASTOMA

Introduction. The main reason for enucleation of the eye when attempting organ-preserving treatment are intraocular tumors that do not respond well to chemotherapy.Purpose. The aim of the study was to find new effective and safe organ-preserving methods of treatment of intraocular refractory and recurrent retinoblastoma (RB).Materials and methods. The study included female chinchilla rabbits. The cell line of human RB was intravitreally inserted into the right eye of each animal. The left eye was a control. After obtaining a stable intraocular growth of RB and prolongation of the growth of RB, human cytotoxic lymphocytes (CTL) were intravitreally injected into the affected and control eye K1 at a concentration of 1 × 106 in 0.1 ml suspension and K2 – 5 × 106 in 0.1 ml, respectively.Results. Histological examination of the removed right eyes in animals confirmed the presence of nodal growth of malignant small-cell tumor on the border of the vascular and retinal membranes (epicenter in the choroid) on the posterior wall of the eye. There was scant lymphoid infiltration, without signs of therapeutic pathomorphosis. In the removed animal»s left eyes there is a preservation of histological structures of the eyeball, without dystrophic changes in the cells of the retina and vascular membranes. In the area of limb unit microcap lymphohistiocytic infiltration (with no elements of the tumor). In the choroid single scattered lymphocytes.Conclusion. A short period of observation of the tumor did not allow conclusions about the effectiveness of CTL, but the concentrations of CTL used in the experiment did not lead to dystrophic changes in retinal cells and the choroid of the eye, which is an important factor in overcoming the toxicity of the proposed adoptive immunotherapy. At the next stage of the experiment, in our opinion, it is necessary to study in more detail the cytotoxic effect on healthy structures of the eye and the effectiveness of CTL in a larger number of affected rabbit eyes, using their different concentrations and multiplicity of administration.

Eye lens radiation exposure in paediatric interventional treatment of retinoblastoma

Retinoblastoma represents 3% of cancers in children under fifteen years of age. The standard paediatric treatment for saving the affected eye is supraselective intra-arterial chemotherapy performed in interventional rooms. In order to address the radiation toxicity due to the angiography, the aim of this study was to determine the typical dose value corresponding to the procedure, estimate the paediatric patients’ eye lens dose and study the relationship between dose indicators and dose to the lens. An automatic dose management software was installed in two interventional rooms to obtain the distribution of the dose indicators kerma-area product and reference-point air kerma, getting a typical value 16 Gy·cm2 and 130 mGy, respectively (n = 35). The eye lens dose estimates were obtained with photoluminescent dosimeters placed on the patient’s eyelids. In the left eye, the entrance surface air kerma was 44.23 ± 2.66 mGy, and 12.72 ± 0.89 mGy in the right eye (n = 10). There was a positive correlation between dose to the lens per procedure and dose indicators, with R2 > 0.65 for both eyes. Based on this information, the threshold for the onset of radiation-induce cataracts (500 mGy) will be exceeded if the treatment is performed for more than 8 sessions.

Retinoblastoma Presentation and Survival: A four-year analysis from a tertiary care hospital.

Objective:To study the clinical presentation, treatment, and outcome of Retinoblastoma (Rb) in a tertiary care hospital of Pakistan.Methods:A retrospective study was conducted in the Department of Pediatric Hematology Oncology, The Indus Hospital (TIH), Karachi from 1st June 2013 to 30th June 2017. Data including patients’ demography, clinical symptoms and duration, laterality, extent of the tumor, type of treatment, relapse, and final outcome were extracted and evaluated with respect to progression and survival.Results:A total of 93 patients were included; 34.4% were boys. The median age at presentation was 30 months. Leukocoria was the commonest symptom (61.3%), followed by proptosis (37.6%). Unilateral disease was seen in 59.1%, extraocular tumors in 43.5% and metastasis in 28.1%. Enucleation was performed on 46.2%, chemotherapy given to 80.6% and external beam radiation therapy to 29.3% patients.Conclusion:Delayed presentation, recurrent disease, extraocular disease and metastasis on presentation were factors affecting outcome in our cohort. Awareness about the early warning signs and symptoms in both public and health professionals for early recognition and timely management are mandatory to decrease morbidity and mortality.

Analysis of the histopathological features of recurrent retinoblastoma after vitrectomy

Objective: To analyze the histopathological features and histopathological risk factors (HRF) of tumor recurrence after vitrectomy in patients with retinoblastoma (RB). Methods: Retrospective case series. Twenty-nine patients (29 eyes) who underwent enucleation from April 2014 to April 2019 at the Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University due to tumor recurrence after vitrectomy in the other hospitals were enrolled and archived. The pathological sections of the other hospitals were read by the pathologists of the department and the pathological report was written. Histopathological features and HRF were analyzed in this group of patients. The HRF used in this study was defined as tumor invasion of the optic nerve, the choroid (the largest diameter ≥ 3 mm and mostly reaching the inner sclera), the sclera, the anterior segment of the eye, and tumor passing through the scleral and growing outside the eyeball. Results: Of the 29 patients with RB recurrence after vitrectomy, 18 (62.1%) were male and 11 (37.9%) were female. The age was 1-10 years with a median age of 3 years. Among 29 eyes, the tumor invaded the ciliary body in 19 eyes (65.5%), the iris in 14 eyes (48.3%), the anterior chamber in 10 eyes (34.5%), and the anterior chamber angle in 7 eyes (24.1%). Of the 29 eyes, 27 eyes (93.1%) had HRF. The most common HRF was invading the anterior segment of the eye(77.8%, 21/27). Conclusions: In patients with recurrence after vitrectomy for RB, the most common tumor invasion site in histopathology is the anterior segment of the eye, particularly the ciliary body. More than 90% of the patients have HRF. Vitrectomy for RB treatment requires a rigorous surgical indication assessment. (Chin J Ophthalmol, 2019, 55: 854-859).

MicroRNA-598 acts as an inhibitor in retinoblastoma through targeting E2F1 and regulating AKT pathway.

Recently, microRNAs (miRNAs) receive more attention due to their role in the pathogenesis of malignancies. Retinoblastoma (RB) is the most serious and harmful malignant tumor in infants and young children with eye diseases, which often endangers the lives of children. This study was designed to determine how miR-598 is involved in RB progression. In this study, quantitative reverse transcription-polymerase chain reaction, Western blot, dual-luciferase reporter, Cell Counting Kit-8, and Transwell assays were adopted to detect miR-598 expression and function in RB. The decreased expression of miR-598 was identified in RB. Overexpression of miR-598 suppressed the viability and metastasis of RB cells. Further, E2F transcription factor 1 (E2F1) is verified as a direct target of miR-598. Furthermore, E2F1 recovered miR-598-mediated-inhibition of cell viability and metastasis in RB. In addition, miR-598 was found to promote cell apoptosis and inactivate the protein kinase B (AKT) pathway in RB. miR-598 suppressed RB cell viability and metastasis through inhibiting E2F1 and inactivating AKT pathway, which may provide a new perspective for RB treatment.

Роль интравитреальной химиотерапии с мелфаланом в комбинированном лечении ретинобластомы с эндофитным характером роста

Роль интравитреальной химиотерапии с мелфаланом в комбинированном лечении ретинобластомы с эндофитным характером роста