Plaque radiotherapy for retinoblastoma: long-term tumor control and treatment complications in 208 tumors

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.

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 Technologies of Drug Delivery to the Posterior Eye Segment Targeting Angiogenesis and Ocular Cancer

Retinoblastoma (RB), a childhood retinal cancer is caused due to RB1 gene mutation which affects the child below 5 years of age. Angiogenesis has been proven its role in RB metastasis due to the presence of vascular endothelial growth factor (VEGF) in RB cells. Therefore, exploring angiogenic pathway by inhibiting VEGF in treating RB would pave the way for future treatment. In preclinical studies, anti-VEGF molecule have shown their efficacy in treating RB. However, treatment requires recurrent intra-vitreal injections causing various side effects along with patient nonadherence. As a result, delivery of anti-VEGF agent to retina requires an ocular delivery system that can transport it in a non-invasive manner to achieve patient compliance. Moreover, development of these type of systems are challenging due to the complicated physiological barriers of eye. Adopting a non-invasive or minimally invasive approach for delivery of anti-VEGF agents would not only address the bioavailability issues but also improve patient adherence to therapy overcoming the side effects associated with invasive approach. The present review focuses on the eye cancer, angiogenesis and various novel ocular drug delivery systems that can facilitate inhibition of VEGF in the posterior eye segment by overcoming the eye barriers.

Surgical resection and orbital iodine-125 brachytherapy for orbital malignancy: a novel treatment for orbital lymphoma

OBJECTIVES

Orbital lymphoma is one of the most common adult orbital malignancies, accounting for approximately 10% of all orbital tumors. This study aimed to analyze the effects of surgical resection and orbital iodine-125 brachytherapy implantation for orbital lymphoma.

PATIENTS AND METHODS

This was a retrospective study. Clinical data of 10 patients were collected from October 2016 to November 2018 and followed up to March 2022. Patients underwent the primary surgery for maximal safe removal of the tumor. After a pathologic diagnosis of a primary orbital lymphoma was established, iodine-125 seed tubes were designed based on the tumor size and invasion range, and direct vision was placed into the nasolacrimal canal or/and under the orbital periosteum around the resection cavity during the secondary surgery. Then, follow-up data, including the general situation, ocular condition, and tumor recurrence, were recorded.

RESULTS

Of the 10 patients, the pathologic diagnoses included extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (6 cases), small lymphocytic lymphoma (1 case), mantle cell lymphoma (2 cases), and diffuse large B-cell lymphoma (1 case). The number of seeds implanted ranged from 16 to 40. The follow-up period ranged between 40 and 65 months. All patients in this study were alive and well had tumors that were completely controlled. No tumor recurrences or metastases occurred. Three patients had dry eye syndrome and two patients had abnormal facial sensation. No patient had radiodermatitis involving the skin around the eye, and no patient had radiation-related ophthalmopathy.

CONCLUSIONS

Based on preliminary observations, iodine-125 brachytherapy implantation appeared to be a reasonable alternative to external irradiation for orbital lymphoma.

LATE CHOROIDAL NEOVASCULAR COMPLICATIONS IN A PATIENT TREATED FOR RETINOBLASTOMA. A CASE REPORT

AIM

Case report of choroidal neovascularization (CNV) detection in patient who was treated for bilateral retinoblastoma in early childhood.

MATERIAL AND METHODS

Patient at 1.5 years of age treated for endophytic retinoblastoma stage 4 (according to the Reese-Ellsworth classification) bilaterally, with a positive mutation in the Rb1 gene. After undergoing bilateral retinal laser treatment and 6 cycles of systemic chemotherapy, the tumor remained inactive without other complications. At the age of 14, the boy developed visual impairment in his left eye with metamorphosis. Based on a local finding and other auxiliary examinations, he was diagnosed with CNV in the macular area at the interface of the tumor scar and the healthy retina of the left eye.

RESULTS

After three applications of anti-VEGF (antibodies blocking vascular endothelial growth factor) substance intravitreally (bevacizumab 1.2 mg), there was a reduction in CNV and also an improvement in visual function.

Ruthenium plaque radiotherapy in the current era of retinoblastoma treatment

BACKGROUND

Two major treatment modalities for retinoblastoma, intraarterial chemotherapy (IAC) and intravitreal chemotherapy (IVitC), have superseded external beam radiotherapy for eye salvage. In this new setting our objectives were to evaluate the indications for plaque radiotherapy, complications, and recurrence rates.

METHODS

Retrospective detailed review of patient's charts was performed for all subjects treated with plaque radiotherapy for retinoblastoma between January 2015 and December 2020.

RESULTS

A total of 12 eyes of 12 patients were included. Mean age at plaque insertion was 45 months (median 29, range 17-150). The treatment dose was 40 Gy to the tumor apex. The indication for plaque radiotherapy was salvage therapy in 11 eyes (92%) and primary treatment in one eye (8%). At last follow-up from plaque insertion (mean 36 months, range 3-67), four (33%) patients had visual acuity better than 0.5 LogMAR and four (33%) had visual acuity worse than 1.0 LogMAR. Radiation-related complications were: one (8%) vitreous haemorrhage, two (16%) non-proliferative radiation retinopathy and one (8%) cataract. Recurrence was detected in four (33%) patients at a mean of 7.8 months (median 5, range 1-20) post-plaque. Globe salvage rate was 75%, as three eyes required enucleation, one to treat recurrence of the tumor treated with plaque and two to treat recurrence of other tumors.

CONCLUSIONS

In the current era of retinoblastoma management, a role for plaque radiotherapy remains for salvage or primary treatment in eyes with localised active tumor, providing tumor control in 66%. Close observation is recommended to both detect recurrence and radiation-related complications.

Long-Term Results after Intraocular Surgery in Treated Retinoblastoma Eyes

Introduction: The aim of the study was to analyze the results of intraocular surgery in treated retinoblastoma eyes and to assess the long-term results with a priority on local recurrences, secondary enucleation, and metastases. Methods: Retrospective noncomparative case series. Results: From March 1964 to January 2020, 42 eyes of 40 retinoblastoma patients underwent intraocular surgery. Time interval between the last therapy and surgery was 9.5 years (mean: 114 months; median: 54.5 months). 31 eyes were treated for radiogenic cataract formation with a gain in visual acuity of 61.3%. One child developed an upper eyelid metastasis, 3 showed second primary malignancies (SPM), one a late recurrence, and 2 eyes were enucleated. Retinal surgery was performed in 17 eyes; 6 eyes were done as a combined procedure. Indications were radiogenic complications in the sense of a vitreous hemorrhage in 11 eyes and a rhegmatogenous retinal detachment in 6 eyes. 41.2% of the treated eyes had a postoperative gain in visual acuity, whereas 9.5% of the eyes could not be preserved in the long term. Regarding systemic involvement 2 patients developed late recurrences and one a SPM. Conclusion: Surgical therapy in treated retinoblastoma is necessary in isolated cases. In our series, cataract surgery was a safe procedure with a good option of a significant increase in visual acuity. As expected, vitreoretinal treated eyes showed a limited gain in visual acuity, a higher risk of late recurrences, and a lower globe retention rate. Therefore, a careful indication and individual risk-benefit analysis are mandatory.

Palladium-103 plaque brachytherapy for retinoblastoma: Long term follow up

Purpose

Radiation has been used in the treatment of retinoblastoma. Herein, we present the novel use of palladium-103 plaque brachytherapy as primary treatment.

Observation

An 8-year-old asymptomatic girl presented was found to have a solitary peripheral retinoblastoma in her right eye. She was treated with primary palladium-103 plaque brachytherapy (47.4 Gray over 5 consecutive days). A secondary, vitreous hemorrhage noted 46 months after irradiation was successfully controlled by laser tumor-demarcation. With 19-years follow up, there has been no clinical scleropathy, or local tumor recurrence. The eye yields 20/20 vision and there has been no systemic metastasis.

Conclusion and importance

Palladium-103 plaque brachytherapy successfully controlled retinoblastoma, while preserving the globe, vision, and life.

Pediatric Cataract Surgery Following Treatment for Retinoblastoma: A Case Series and Systematic Review

PURPOSE

To determine the visual and refractive outcomes and the ocular and systemic complications of cataract surgery in eyes treated for retinoblastoma.

DESIGN

Retrospective consecutive case series and systematic review.

METHODS

Children <18 years of age with retinoblastoma who underwent surgery for secondary cataract between 2000 and 2020 were reviewed. Medline (OVID), Embase, Web of Science, and the Cochrane database were searched from inception to August 2020.

RESULTS

A total of 15 eyes of 15 children were included. The mean age at retinoblastoma diagnosis was 12 months (median, 14; interquartile range [IQR], 4-19). Cataract developed at a mean age of 39 months (median, 31; IQR, 20-52), secondary to multiple treatments (n = 7), pars-plana vitrectomy (n = 3), external-beam radiotherapy (n = 2), laser (n = 2), and retinal detachment (n = 1). The mean preoperative quiescent interval was 44 months (median, 28; IQR, 15-64). Primary intraocular lens implantation was performed in 93%, posterior capsulotomy in 40%, and anterior vitrectomy in 33% of participants. Postoperatively, 100% had improved fundus visibility and 73% had improved vision. Complications included visual axis opacification (11 of 15), capsular phimosis (5 of 15), and zonulopathy (3 of 15). No patient developed intraocular recurrence, extraocular extension, or metastasis at a mean of 76 months (median, 78; IQR, 29-128) follow-up. The systematic review identified 852 studies, with 18 meeting inclusion criteria. Across all studies (n = 220 children), intraocular recurrence occurred in 6%, globe salvage in 91%, and extraocular extension and metastasis in <1%.

CONCLUSIONS

Modern retinoblastoma therapies, including intravitreal chemotherapy and vitrectomy, cause secondary cataract. Following cataract surgery, intraocular recurrence risk is low and extraocular spread is rare. Although surgery improves tumor visualization, visual prognosis may be limited by several factors. Challenges include biometry limitations and a high incidence of zonulopathy.

Iodine-125 Plaque Radiotherapy for Retinoblastoma Recurrence Following Intra-arterial Chemotherapy

PURPOSE

To assess the efficacy and toxicity of Iodine-125 (I-125) plaque radiotherapy for retinoblastoma following intra-arterial chemotherapy (IAC).

METHODS

Clinical records of patients with retinoblastoma who received I-125 plaque radiotherapy after IAC at the Ocular Oncology Service at Wills Eye Hospital between December 1, 2009 and April 30, 2020, were retrospectively reviewed.

RESULTS

Forty-one retinoblastomas in 41 eyes of 41 patients were treated with I-125 plaque radiotherapy after IAC at a median age of 32 months. The indication for plaque radiotherapy was solid tumor recurrence with or without overlying subretinal/vitreous seeds (n = 33, 80%), subretinal seeds alone (n = 6, 15%), and vitreous seeds alone (n = 2, 5%). The median irradiated basal diameter and thickness was 9 and 4 mm, respectively. Mean radiation dose to tumor apex was 3,483 centigray (cGy) delivered at mean rate of 35 cGy/hr. The irradiated site was controlled in 39 eyes (95%) at a median of 20 months after plaque radiotherapy for solid tumor (31 of 33, 94%), subretinal (6 of 6,100%), and vitreous seeds (2 of 2, 100%). A subgroup of tumors occurring within an ischemic retinal/choroidal field was identified on fluorescein angiography (n = 24) and demonstrated control in 22 of 24 (92%). Using Kaplan-Meier analysis, radiation complications at 2 years included vitreous hemorrhage (37%), retinopathy (28%), papillopathy (18%), and cataract (18%). Five eyes (12%) were enucleated for recurrence outside the irradiated area, chronic vitreous hemorrhage, and/or total retinal detachment.

CONCLUSIONS

Iodine-125 plaque radiotherapy provided 95% control for retinoblastoma tumors that failed IAC, including those in ischemic fields untreatable with further chemotherapy. Radiation complications should be anticipated in eyes exposed to substantial chemotherapy. [J Pediatr Ophthalmol Strabismus. 2022;59(3):164-171.].

Short-term changes of cornea and tear film after ruthenium-106 plaque therapy for intraocular tumors

Purpose:

Plaque therapy is a well-recognized treatment for intraocular tumors. In current study, we aimed to prospectively investigate the short-term effects of ruthenium 106 (Ru-106) plaque therapy on the cornea and ocular surface parameters.

Methods:

Twenty-five patients diagnosed with choroidal melanoma which undergone Ru-106 plaque therapy from 2016 to 2018 were included. Tear osmolarity, tear film break-up time, Schirmer test I, fluorescein dye staining based on Oxford staining method; Ocular Surface Disease Index (OSDI) questionnaire and corneal specular microscopy were performed. These tests were assessed preoperatively and then 3 months postoperatively.

Results:

The mean (±SD) age of subjects was 48.52 ± 15.18 years. The patients were followed for a mean(±SD) period of 3.64 ± 2.40 months. Total mean (+SD) delivered radiation dose to the tumor apex and total received radiation by the sclera was 83.20 ± 26.31 and 640.65 ± 472.69 Gray (Gy), respectively. In longitudinal analysis, OSDI score and Oxford staining score increased significantly (P = 0.002 for both variables) and the prevalence of dry eye disease (DED) increased from 20% preoperatively to 72% at 3 months postoperatively (P = 0.001).The changes in the all specular microscopy parameters were statistically nonsignificant (all P values > 0.05).

Conclusion:

There is a considerable increase in the rate of DED following plaque therapy for the treatment of choroidal melanoma in short-term follow-up. The OSDI questionnaire and fluorescein staining test are valuable tools for early detection of DED postoperatively.

Retinoblastoma in Taiwan: survival and clinical characteristics

PURPOSE

To figure out the impact of national health insurance program and treatment modalities on the clinical outcomes of patients with retinoblastoma.

STUDY DESIGN

Retrospective cohort study.

METHODS

Enrolled patients were classified into three groups according to the time period in which their initial diagnosis was performed: patients diagnosed before 1995 (group 1), patients diagnosed in the time period 1995-2010 (group 2), patients diagnosed after 2010 (group 3). Comparison was made of clinical features including presenting signs, tumor spreading, and treatment modes. Survival and globe salvage rates were analyzed within each group.

RESULTS

There were 157 patients (202 eyes) enrolled from 1978 to 2015. The overall mortality rate was 24.2%. The overall 5-year survival rate was 63.4%, 73.8%, 89.1% in the three time periods respectively (P = 0.007). The 5-year survival improved continuously in both unilateral and bilateral disease (P = 0.057; P = 0.015). Patients without extraocular spreading or diagnosed before 2 years of age had a better 5- year survival of 97.4% and 81.1% respectively. The globe salvage rate improved from 8.2%, 14.5%, to 35.1% (P < 0.001). The globe salvage rate was 46.9% in patients who received ophthalmic artery chemosurgery (OAC) and 6.4% in patients not received OAC.

CONCLUSIONS

Improvement of survival and globe salvage rate was observed over time periods. National health insurance program has made medical care easily accessible to the public, leading to earlier diagnosis and treatment. Different treatment modes could achieve a better clinical outcome; among the new treatment modalities, OAC played an important role.

Rare tumors: Retinoblastoma, nasopharyngeal cancer, and adrenocorticoid tumors

The role of surgery, chemotherapy, and radiation therapy for retinoblastoma has evolved considerably over the years with the efficacy of intraarterial chemotherapy and the high incidence of secondary malignant neoplasms following radiation therapy. The use of spot scanning intensity-modulated proton therapy may reduce the risk of secondary malignancies. For pediatric nasopharyngeal carcinoma, the current standard of care is induction chemotherapy followed by chemoradiation therapy. For adrenocortical carcinoma, the mainstay of treatment is surgery and chemotherapy. The role of radiation therapy remains to be defined.

The Impacts of Episcleral Plaque Brachytherapy on Ocular Motility

Background: To investigate the effect of various factors on ocular motility disturbance after episcleral plaque brachytherapy with Ruthenium 106 (¹⁰⁶Ru).Methods: Twenty consecutive patients who underwent plaque brachytherapy for all types of intraocular tumors were included in this interventional prospective case series. Ruthenium-106 was used with a mean total dose of 93.2 ± 21.2 Gy toward the tumor apex. Full orthoptic examinations were performed before and after the surgery.Results: The average follow-up time was 6 months (range: 4-9 months). Two (10%) out of 20 patients developed exotropia. The mean age of patients without strabismus was higher than the patients with strabismus (49.8 ± 10.7 years compared to 23 ± 4.2 years, respectively) (p = .011). Strabismus was observed in the patients who had tumors with larger apical diameters (7.6 ± 2 mm compared to 4.1 ± 0.9 mm, respectively) (p = .021). The mean radiation dose to the tumor base in the group with strabismus was higher than the group without motility disturbance (1046.5 ± 604.1 Gy compared to 384.3 ± 175.3, respectively) (p = .021). Most tumors were located in the inferotemporal fundus (30%), followed by supratemporal location (25%), supranasal (10%), and macular region (10%). A higher percentage of patients with postoperative strabismus underwent muscle manipulation compared to the patients who did not develop this complication (100% compared to 38.9%).Conclusion: Manipulation of the extraocular muscles, high doses of radiation, and low vision could cause strabismus after episcleral plaque brachytherapy.

Neonatal Retinoblastoma

Retinoblastoma is the most common ocular malignancy of childhood. With an estimated 300 cases annually in the United States, retinoblastoma is nevertheless considered a rare tumor. Although retinoblastoma primarily affects younger children, diagnosis during the neonatal age range is less common. However, an understanding of patients at risk is critical for appropriate screening. Early detection and treatment by a multidisciplinary specialty team maximizes the chance for survival and ocular/vision salvage while minimizing treatment-related toxicity. Testing for alterations in the RB1 gene has become standard practice, and informs screening and genetic counseling recommendations for patients and their families.

Applications of iodine-125 plaque radiotherapy for residual or recurrent retinoblastoma

OBJECTIVE

To determine the role of iodine-125 plaque radiotherapy (IPR) as a secondary treatment for localized (solitary or multiple) residual (partially regressed) or recurrent (regrowth after ≥6 months stability) retinoblastoma in the era of systemic and/or regional chemotherapy.

DESIGN

A single-institute retrospective, noncomparative, interventional case series managed between July 2014 and June 2019.

PARTICIPANTS

Thirteen consecutive eyes of 12 patients with 14 residual or recurrent retinoblastoma tumors treated with IPR. Patients who had to follow up <1 year post-IPR were excluded except for those who had enucleation.

METHODS

Data collected included pre-IPR treatments, tumor characteristics at IPR, and post-IPR anatomical outcome (local tumor control and globe salvage) and functional outcome (radiation complications).

RESULTS

Local tumor control was achievable in 12 of 14 tumors. Local recurrences were observed in 2 of 5 tumors that exhibited fish-flesh regression after IPR (p = 0.04). Globe salvage was possible in 11 eyes (12 tumors). Only 2 eyes were legally blind and the remaining 9 eyes had vision >20/125. Radiation-induced complications included radiation retinopathy (4/11), radiation papillopathy (1/11), diffuse vitreous hemorrhage (4/11). Eyes with fish-flesh-regressed tumours tended to show more complications, but were statistically insignificant (p = 0.09, Fisher exact test). There was no association of time to IPR (early <6 months vs late >6 months) with occurrence of tumor recurrence or complications (p > 0.05).

CONCLUSION

IPR offers satisfactory local tumor control and globe salvage in localized recurrent/residual retinoblastoma. Fish-flesh tumor regression after IPR should be closely monitored for further recurrences.

Dosimetric comparison of different radiotherapy techniques for the treatment of Retinoblastoma

Aim:

This study aims to compare the dosimetric parameters among four different external beam radiotherapy techniques used for the treatment of retinoblastoma.

Materials and methods:

Computed tomography (CT) sets of five retinoblastoma patients who required radiotherapy to one globe were included. Four different plans were generated for each patient using three dimensional conformal radiotherapy (3DCRT), intensity modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and VMAT using flattening filter free (VMAT-FFF) beam techniques. Plans were compared for target coverage and organs at risk (OARs) sparing.

Results:

The target coverage of planning target volume (PTV) for all the four modalities were clinically acceptable with a V95 of 95 ± 0%, 97·6 ± 1·87%, 99·3 ± 0·5% and 99·17 ± 0·45% for 3DCRT, IMRT, VMAT and VMAT-FFF respectively. The VMAT and IMRT plans had better target coverage than the 3DCRT plans (p = 0·001 and p = 0·07 respectively). IMRT and VMAT plans were also found superior to 3DCRT plans in terms of OAR sparing like brainstem, optic chiasm, brain (p < 0·05). VMAT delivered significantly lower dose to the brainstem and contralateral optic nerve in comparison to IMRT. Use of VMAT-FFF beams did not show any benefit over VMAT in target coverage and OAR sparing.

Conclusion:

VMAT should be preferred over 3DCRT and IMRT for treatment of retinoblastoma owing to better target coverage and less dose to most of the OARs. However, IMRT and VMAT should be used with caution because of the increased low dose volumes to the OARs like contralateral lens and eyeball.

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.

Radiation-Induced Cerebro-Ophthalmic Effects in Humans

Exposure to ionizing radiation (IR) could affect the human brain and eyes leading to both cognitive and visual impairments. The aim of this paper was to review and analyze the current literature, and to comment on the ensuing findings in the light of our personal contributions in this field. The review was carried out according to the PRISMA guidelines by searching PubMed, Scopus, Embase, PsycINFO and Google Scholar English papers published from January 2000 to January 2020. The results showed that prenatally or childhood-exposed individuals are a particular target group with a higher risk for possible radiation effects and neurodegenerative diseases. In adulthood and medical/interventional radiologists, the most frequent IR-induced ophthalmic effects include cataracts, glaucoma, optic neuropathy, retinopathy and angiopathy, sometimes associated with specific neurocognitive deficits. According to available information that eye alterations may induce or may be associated with brain dysfunctions and vice versa, we propose to label this relationship "eye-brain axis", as well as to deepen the diagnosis of eye pathologies as early and easily obtainable markers of possible low dose IR-induced brain damage.

BRAIN AND EYE AS POTENTIAL TARGETS FOR IONIZING RADIATION IMPACT. Part І. THE CONSEQUENCES OF IRRADIATION OF THE PARTICIPANTS OF THE LIQUIDATION OF THE CHORNOBYL ACCIDENT

BACKGROUND

Exposure to ionizing radiation could affect the brain and eyes leading to cognitive and vision impairment, behavior disorders and performance decrement during professional irradiation at medical radiology, includinginterventional radiological procedures, long-term space flights, and radiation accidents.

OBJECTIVE

The objective was to analyze the current experimental, epidemiological, and clinical data on the radiation cerebro-ophthalmic effects.

MATERIALS AND METHODS

In our analytical review peer-reviewed publications via the bibliographic and scientometric bases PubMed / MEDLINE, Scopus, Web of Science, and selected papers from the library catalog of NRCRM - theleading institution in the field of studying the medical effects of ionizing radiation - were used.

RESULTS

The probable radiation-induced cerebro-ophthalmic effects in human adults comprise radiation cataracts,radiation glaucoma, radiation-induced optic neuropathy, retinopathies, angiopathies as well as specific neurocognitive deficit in the various neuropsychiatric pathology including cerebrovascular pathology and neurodegenerativediseases. Specific attention is paid to the likely stochastic nature of many of those effects. Those prenatally and inchildhood exposed are a particular target group with a higher risk for possible radiation effects and neurodegenerative diseases.

CONCLUSIONS

The experimental, clinical, epidemiological, anatomical and pathophysiological rationale for visualsystem and central nervous system (CNS) radiosensitivity is given. The necessity for further international studieswith adequate dosimetric support and the follow-up medical and biophysical monitoring of high radiation riskcohorts is justified. The first part of the study currently being published presents the results of the study of theeffects of irradiation in the participants of emergency works at the Chornobyl Nuclear Power Plant (ChNPP).

Glaucoma incidence risk in a cohort of Mayak PA workers occupationally exposed to ionizing radiation

Glaucoma is a major cause of visual impairment, and secondary glaucoma manifested as neovascular glaucoma has long been known to occur following high-dose fractionated radiation therapy. In contrast, little is known as to whether ionizing radiation exposure causes primary glaucoma, except that a single study in Japanese atomic bomb survivors has reported a significantly increase risk. Therefore, the effect of lower dose and lower dose rate remains unclear. Here we report that in Russian Mayak Production Association workers occupationally exposed to chronic radiation for prolonged periods, incidence of total primary glaucoma and primary open-angle glaucoma is significantly associated with various non-radiation factors (sex, attained age, and cataract diagnosed prior to glaucoma), but neither with cumulative dose from external γ-rays nor with cumulative neutron dose nor with the unweighted sum of cumulative γ and neutron doses. The present results suggest for the first time that chronic radiation exposure does not cause primary glaucoma, although the analyses need to be made in other cohorts exposed at various dose and dose rate.

Association between radiation, glaucoma subtype, and retinal vessel diameter in atomic bomb survivors

We examined the relationship between glaucoma subtype and retinal vascular caliber as markers of ocular circulation. Subjects were Japanese atomic bomb survivors in Hiroshima and Nagasaki. After a screening examination, potential cases were subjected to further definitive examination. The diameters of central retinal artery and vein equivalents (CRAE and CRVE) on digitized retinal photographs were measured using an established method. Generalized linear regression analyses were used to examine the associations among vessel diameters, radiation exposure, and prevalence of glaucoma subtypes among the study subjects. We identified 196 cases of glaucoma (12%) based on optic disc appearance, perimetry results, and other ocular findings. The main subtypes were primary angle-closure glaucoma, primary open-angle glaucoma and normal-tension glaucoma (NTG). NTG was the dominant subtype (78%). NTG was negatively associated with CRAE and CRVE, and positively associated with radiation dose. CRVE was negatively associated with radiation dose and the association was unclear for CRAE. The smaller retinal vessel caliber in NTG patients than in subjects without glaucoma may indicate an association between ocular blood flow and the pathogenesis of NTG. However, significant relationships among vessel calibers, NTG and radiation exposure were not clear.

Episcleral brachytherapy for retinoblastoma

BACKGROUND/AIMS

To report visual outcomes, survival outcomes and complications following episcleral brachytherapy (EB) for retinoblastoma.

METHODS

Retrospective review of retinoblastoma cases treated with EB in a single institution. Survival outcomes were analysed using the Kaplan-Meier method.

RESULTS

Eleven tumours of 11 eyes were treated with either iodine-125 or ruthenium-106 EB with a mean apical dose of 44 Gy. The tumours were classified as group B in 5 (46%), C in 3 (27%) or D in 3 (27%) eyes, respectively. Mean follow-up time was 75.4 months. EB served as primary treatment in 3 eyes (27%) and secondary treatment in 8 eyes (73%). Final visual acuity was better than 20/200 in 70% of cases. Globe preservation was achieved in 9 (82%) eyes. Local recurrence occurred in 18% of cases at a mean onset of 17.4 months after EB. Two group D tumours that recurred after secondary EB underwent enucleation. Mean onset of radiation retinopathy was 17.4 months following EB. No metastatic or fatal events were recorded. Kaplan-Meier analysis showed recurrence-free survival and ocular survival of 80% and overall survival of 100% at 5 years after EB.

CONCLUSION

EB is an effective primary or secondary treatment modality for selected retinoblastoma eyes (groups B and C). Advanced group D tumours may represent a risk factor for local recurrence. Visually significant complications such as radiation retinopathy should be anticipated.

A convex windowless extrapolation chamber to measure surface dose rate from 106 Ru/106 Rh episcleral plaques

PURPOSE

A convex windowless extrapolation chamber was developed as a primary measurement device to determine surface dose rate from curved ¹⁰⁶ Ru/¹⁰⁶ Rh episcleral plaques.

METHODS

A convex extrapolation chamber without an entrance window was constructed for this work, and surface dose rate measurements were performed with two curved CCB-type ¹⁰⁶ Ru/¹⁰⁶ Rh plaques (S/N 2545 and 2596) manufactured by Eckert & Ziegler BEBIG. FARO ® Gage measurements were performed to verify the radius of curvature for the convex electrode and the concave plaque surface. Furthermore, the collecting electrode area was verified through capacitance measurements. Chamber correction factors for divergence and backscatter were generated using the EGSnrc cavity user code. For each source, surface dose rate was measured with the convex extrapolation chamber and compared with on-contact measurements made with curved un-laminated EBT3 film strips. A Monte Carlo correction was generated for radiochromic film measurements to account for volume averaging within the active layer and effects of phantom scatter. Additionally, extrapolation chamber results for each plaque were compared with scintillation detector measurements performed by the manufacturer. For the second source (S/N 2596), a comparison was also made with the Monte Carlo-corrected surface dose rate measured at the National Physical Laboratory (NPL) using cylindrical alanine pellets. Finally, source measurements were performed using conventional ionization chambers (Exradin A26, A1SL, and A20) within a custom fixture to investigate the transfer of extrapolation chamber surface dose rate to clinics.

RESULTS

For the first ¹⁰⁶ Ru/¹⁰⁶ Rh plaque (S/N 2545), average surface dose rate from the convex windowless extrapolation chamber was found to be 1.5% higher than the corresponding value from curved un-laminated EBT3 film measurements and 5.6% lower than the manufacturer value. For the second source (S/N 2596), the extrapolation chamber surface dose rate was 2.5% higher than the un-laminated EBT3 film result, 4.5% lower than the manufacturer value, and 3.9% higher compared to corrected alanine measurements made at NPL. Total uncertainty in the extrapolation chamber measurement was estimated to be approximately  ± 7.0% (k = 2). For the plaque measurements made using conventional ionization chambers with a custom fixture, surface dose rate from the transfer technique was found to agree within 3.8% with the expected convex extrapolation chamber result for S/N 2596.

CONCLUSIONS

A convex windowless extrapolation chamber was developed as a primary measurement device for ¹⁰⁶ Ru/¹⁰⁶ Rh plaques. Through comparison with the extrapolation chamber, the accuracy of surface dose rate measurements from current dosimetry techniques was assessed and agreement was seen within 5.6%. Finally, it was found that conventional ionization chambers could be calibrated with a reference ¹⁰⁶ Ru/¹⁰⁶ Rh plaque in order to transfer the extrapolation chamber result for surface dose rate to clinics.

Animal models of radiation retinopathy - From teletherapy to brachytherapy

Radiation retinopathy is a serious vision-impairing complication of radiation therapy used to treat ocular tumors. Characterized by retinal vasculopathy and subsequent retinal damage, the first sign of radiation retinopathy is the preferential loss of vascular endothelial cells. Ensuing ischemia leads to retinal degradation and late stage neovascularization. Despite the established disease progression, the pathophysiology and cellular mechanisms contributing to radiation retinopathy remain unclear. Clinical experience and basic research for other retinal vasculopathies, such as diabetic retinopathy and retinopathy of prematurity, can inform our understanding of radiation retinopathy; however, the literature investigating the fundamental mechanisms in radiation retinopathy is limited. Treatment trials have shown modest success but, ultimately, fail to address the cellular events that initiate radiation retinopathy. Animal models of radiation retinopathy could provide means to identify effective therapies. Here, we review the literature for all animal models of radiation retinopathy, summarize anatomical highlights pertaining to animal models, identify additional physiological factors to consider when investigating radiation retinopathy, and explore the use of clinically relevant tests for studying in vivo models of radiation retinopathy. We encourage further investigation into the mechanistic characterization of radiation retinopathy in the hope of discovering novel treatments.

Glaucomagenesis following ionizing radiation exposure

Glaucoma is a group of optic neuropathies causing optic nerve damage and visual field defects, and is one of the leading causes of blindness. Nearly a century has passed since the first report of glaucoma manifested following ionizing radiation therapy of cancers. Nevertheless, associations between glaucoma and radiation exposures, a dose response relationship, and the mechanistic underpinnings remain incompletely understood. Here we review the current knowledge on manifestations and mechanisms of radiogenic glaucoma. There is some evidence that neovascular glaucoma is manifest relatively quickly, within a few years after high-dose and high dose-rate radiotherapeutic exposure, but little evidence of excess risks of glaucoma after exposure to much lower doses or dose rates. As such, glaucoma appears to have some of the characteristics of a tissue reaction effect, with a threshold of at least 5 Gy but possibly much higher.

Radiation Retinopathy 47 Years following Brachytherapy for Retinoblastoma

A 50-year-old female who had undergone enucleation in the left eye and brachytherapy in the right eye for retinoblastoma at the age of 2 years was diagnosed with nonproliferation radiation retinopathy 47 years following the initial treatment. The patient had noticed black spots in her vision (scotomas) that interfered with reading. New onset of microaneurysms and lipid exudation threatening the foveola was noted on examination of the right eye. Initial visual acuity (VA) was 20/25. Optical coherence tomography showed no evidence of macular edema, but parafoveal lipid exudation was present. On fluorescein angiography, no sign of neovascularization or macular ischemia was observed. Direct focal treatment of microaneurysms was performed to prevent progression of the radiation retinopathy and vision loss. At 18 months' follow-up following focal laser, VA remained stable at 20/25 and there was a regression of the retinopathy.

Retinoblastoma for Pediatric Ophthalmologists

Retinoblastoma can present in 1 or both eyes and is the most common intraocular malignancy in childhood. It is typically initiated by biallelic mutation of the RB1 tumor suppressor gene, leading to malignant transformation of primitive retinal cells. The most common presentation is leukocoria, followed by strabismus. Heritable retinoblastoma accounts for 45% of all cases, with 80% being bilateral. Treatment and prognosis of retinoblastoma is dictated by the disease stage at initial presentation. The 8th Edition American Joint Committee on Cancer (AJCC) TNMH (tumor, node, metastasis, heritable trait) staging system defines evidence-based clinical and pathological staging for overall prognosis for eye(s) and child. Multiple treatment options are available in 2018 for retinoblastoma management with a multidisciplinary team, including pediatric ocular oncology, medical oncology, radiation oncology, genetics, nursing, and social work. Survival exceeds 95% when disease is diagnosed early and treated in centers specializing in retinoblastoma. However, survival rates are less than 50% with extraocular tumor dissemination. We summarize the epidemiology, genetics, prenatal screening, diagnosis, classification, investigations, and current therapeutic options in the management of retinoblastoma.

Retinoblastoma

Retinoblastoma represents 3% of all childhood cancers, and is the most common intraocular malignancy of childhood. It is fatal, if untreated. White eye reflex, also known as leukocoria, is the commonest sign, followed by strabismus. The pediatricians have a very important role to play in the diagnosis of this relatively rare, but easily detectable tumor. Early diagnosis yields better results. The management of retinoblastoma has gradually evolved over the past few decades, with an aim to not only preserve life and eye, but also optimize residual vision. The treatment of retinoblastoma is multimodal, with chemotherapy, focal treatment including trans-pupillary thermotherapy, cryotherapy and laser photocoagulation, radiation therapy and surgery, all playing a vital role. Intravenous chemotherapy has been the mainstay of treatment for the past two decades, and still continues to be the most extensively used eye-saving modality of treatment. Periocular and intravitreal chemotherapy have specific indications in the management of retinoblastoma. Intra-arterial chemotherapy has emerged as a promising alternative for advanced and refractory retinoblastoma, both as a primary and secondary therapy. Recent advances in genetics of retinoblastoma have also helped in improving the overall clinical management of this malignancy.

Challenges and differences in external radiation therapy for retinoblastoma: from standard techniques to new developments

AIMS

The purpose of this study is to calculate the treatment plans and to compare the dose distributions and dose-volume histograms (DVH) for 6 external radiotherapy techniques for the treatment of retinoblastoma as well as intensity-modulated radiotherapy (IMRT) and fractionated stereotactic radiotherapy (Cyberknife).

METHODS

Treatment plans were developed using 6 techniques, including an en face electron technique (ET), an anterior and lateral wedge photon technique (LFT), a 3D conformal (6 fields) technique (CRT), an inverse plan IMRT, tomotherapy, and conventional focal stereotactic external beam radiotherapy with Cyberknife (SBRT). Dose volume analyses were carried out for each technique.

RESULTS

All techniques except electron provided similar target coverage. When comparing conformal plan with IMRT and SBRT, there was no significant difference in planning target volume dose distribution. The mean volume of ipsilateral bony orbit received more than 20 Gy, a suggested threshold for bone growth inhibition. The V20 Gy was 73% for the ET, 57% for the LFT, 87% for the CRT, 65% for the IMRT, 66% for the tomotherapy, and 2.7% for the SBRT.

CONCLUSIONS

This work supports the potential use of IMRT and SBRT to spare normal tissues in these patients.

Dosimetric advantage of volumetric modulated arc therapy in the treatment of intraocular cancer

Objective

The purpose of this study is to investigate the dosimetric advantages of volumetric modulated arc therapy (VMAT) in the treatment of intraocular cancer by comparing it directly with three-dimensional conformal radiotherapy (CRT) and intensity-modulated radiotherapy (IMRT).

Methods

CRT plan, 7f-IMRT plan, and one-arc VMAT plan were generated for 14 intraocular cancer patients. Dosimetric and biological quality indices for target volume and organs at risks (OARs) were evaluated and compared.

Results

The target coverage presented by V95 for CRT, IMRT and VMAT were 95.02% ± 0.67%, 95.51% ± 2.25%, and 95.92% ± 3.05%, respectively. The homogeneity index (HI) for CRT, IMRT and VMAT were 0.15 ± 0.05, 0.23 ± 0.05, and 0.23 ± 0.06, respectively. IMRT and VMAT greatly decreased the dose to ipsilateral lens compared with CRT with a D1 of 2972.66 ± 1407.12 cGy, 3317.82 ± 915.28 cGy and 4809.54 ± 524.60 cGy for IMRT, VMAT and CRT, respectively. Similar results were observed for ipsilateral eyeballs. IMRT and VMAT also spared better on brainstem, optical nerves and optical chiasm compared CRT. However, CRT achieved lower dose to the eyeballs compared with IMRT and VMAT. VMAT and IMRT showed mixed results on target coverage and OAR sparing. The average MUs and delivery time of IMRT and VMAT were 531.25 ± 81.21 vs. 400.99 ± 61.49 and 5.05 ± 0.53 vs.1.71 ± 0.69 min, respectively.

Conclusions

Although no clear distinction on PTV coverage among CRT, IMRT and VMAT plans was observed in the treatment of intraocular cancer, VMAT and IMRT achieved better homogeneity and conformity for target volume, and delivered fewer doses to ipsilateral lens and eyeballs compared with CRT. However, VMAT and IMRT increased the low dose volume to the contralateral OARs. Although VMAT and IMRT showed mixed results on target coverage and OAR sparing, VMAT decreased MU and delivery time significantly compared with IMRT. VMAT is a promising and feasible external beam radiotherapy technique in the treatment of intraocular cancer patients.

Diffuse Anterior Retinoblastoma with Globe Salvage and Visual Preservation in 3 Consecutive Cases

PURPOSE

Diffuse anterior retinoblastoma is an exquisitely rare variant of retinoblastoma in which the tumor resides in the anterior segment of the eye, without apparent retinal involvement. Previously published cases have been managed with enucleation. We describe globe salvage and visual preservation in 3 consecutive cases using chemotherapy and radiotherapy.

DESIGN

Retrospective case series.

PARTICIPANTS

Three children with diffuse anterior retinoblastoma.

METHODS

Plaque radiotherapy plus intravenous chemotherapy.

MAIN OUTCOME MEASURES

Globe and vision preservation.

RESULTS

The mean patient age at presentation elsewhere was 5.7 years (median, 7; range, 3-7 years). There were 2 white female patients and 1 African American male patient. The initial observation by parents/caregiver was reduced vision (n = 1), red eye (n = 1), or cloudy eye (n = 1), and the initial finding by physician was iris tumor (n = 2) or hyphema (n = 1). Referring diagnosis was iris melanoma (n = 1), infectious endotheliitis (n = 1), and possible tumor (nonspecified) (n = 1). At our evaluation, visual acuity was 20/50 to 20/60 (n = 2) and fix no follow (n = 1). In all cases, the opposite eye was normal. Mean intraocular pressure was 20 mm Hg (median, 16; range, 15-30 mmHg). Our examination revealed solid iris tumor (n = 3), ciliary body involvement (n = 2), and anterior chamber seeding (n = 3). In no case was there choroidal or retinal tumor, vitreous seed or subretinal seed, or extrascleral extension. Clear corneal fine-needle aspiration biopsy confirmed the diagnosis as retinoblastoma in each case. Treatment included plaque radiotherapy (n = 3) plus additional systemic chemotherapy (n = 2). At mean follow-up of 35 months (median, 34; range, 20-51 months), there has been no recurrence, extrascleral extension, enucleation, metastasis, or death. In all 3 cases, cataract surgery was necessary at a mean interval of 16 months after complete and stable regression of retinoblastoma.

CONCLUSIONS

The rare diffuse anterior form of retinoblastoma can be managed with globe-salvaging alternatives and with visual preservation in selected cases.

Risk definition and management strategies in retinoblastoma: current perspectives

This manuscript focuses on high-risk factors of metastatic disease in retinoblastoma and evaluation of the current treatments of retinoblastoma. Presence of histopathologic high-risk factors is associated with a higher risk of local recurrence and systemic metastasis. Currently, globe-sparing therapies, including systemic chemotherapy, intra-arterial chemoreduction, intravitreal chemotherapy, focal consolidation, and combination therapies, are being used and investigated actively. Major advances are being made in the diagnosis and management of retinoblastoma that will lead to improved morbidity and mortality rates in patients with retinoblastoma. By saving the globes, fronting with some high-risk factors for metastasis would be inevitable. International multi-institutional prospective studies could resolve current uncertainties regarding the main tumor treatment regimens for each patient and indications for chemoprophylaxis for high-risk-factor-bearing retinoblastoma cases.

Impairments that influence physical function among survivors of childhood cancer

Children treated for cancer are at increased risk of developing chronic health conditions, some of which may manifest during or soon after treatment while others emerge many years after therapy. These health problems may limit physical performance and functional capacity, interfering with participation in work, social, and recreational activities. In this review, we discuss treatment-induced impairments in the endocrine, musculoskeletal, neurological, and cardiopulmonary systems and their influence on mobility and physical function. We found that cranial radiation at a young age was associated with broad range of chronic conditions including obesity, short stature, low bone mineral density and neuromotor impairments. Anthracyclines and chest radiation are associated with both short and long-term cardiotoxicity. Although numerous chronic conditions are documented among individuals treated for childhood cancer, the impact of these conditions on mobility and function are not well characterized, with most studies limited to survivors of acute lymphoblastic leukemia and brain tumors. Moving forward, further research assessing the impact of chronic conditions on participation in work and social activities is required. Moreover, interventions to prevent or ameliorate the loss of physical function among children treated for cancer are likely to become an important area of survivorship research.

Retinoblastoma: An overview

Retinoblastoma is the most common intraocular malignancy in children, with a reported incidence ranging from 1 in 15,000 to 1 in 18,000 live births. It is second only to uveal melanoma in the frequency of occurrence of malignant intraocular tumors. Pawius described retinoblastoma as early as in 1597 referred to the tumor as fungus hematodes and suggested enucleation as the primary mode of management. The discovery of ophthalmoloscope in 1851 facilitated recognition of specific clinical features of retinoblastoma. Initially thought to be derived from the glial cells, it was called a glioma of the retina by Virchow (1864). Flexner (1891) and Wintersteiner (1897) believed it to be a neuroepithelioma because of the presence of rosettes. Later, there was a consensus that the tumor originated from the retinoblasts and the American Ophthalmological Society officially accepted the term retinoblastoma in 1926. Retinoblastoma was associated with near certain death just over a century ago. There has been a dramatic change in the overall management of retinoblastoma in the last decade. Specific genetic protocols have been able to make pre natal diagnosis of retinoblastoma. Early diagnosis and advancements in focal therapy have resulted in improved eye and vision salvage. This article explains the complexity of retinoblastoma, genetic association, clinical features, management and prognosis.

Outcome of retinoblastoma following limited sessions of intra-arterial chemotherapy in iran

Background:

The management of retinoblastoma remains a challenge to the multidisciplinary team, particularly as treatment affects not only visual outcomes, but also ocular retention and morbidity. Management of retinoblastoma has evolved over the past two decades.

Objectives:

To report the result of intra-ophthalmic artery chemotherapy (IAC) for the treatment of refractory and advanced retinoblastoma tumors.

Patients and Methods:

All patients who had failed to respond adequately to previous treatments and six naive patients with advanced retinoblastoma, receiving IAC between 2009 and 2012, were included in this institutional interventional case series. The patients received 1-2 treatments of IAC given 4-8 weeks apart. Complete response was defined as regressed tumor and complete disappearance of seeding clinically and partial response was defined as partial regression of the tumor with live parts of the tumor and/or lessening of seeds, but not complete disappearance of them clinically.

Results:

A total of 24 eyes of 24 patients were treated with IAC during the study period. The mean age at the time of IAC was 38.9 months (14-120 months), and the mean follow-up was 16.8 months (3-36 months) after IAC. Tumor control was achieved in 14 eyes (58.3%). Type 3 (combined fleshy and calcified remnants) was the most common type of regression (37.5%). Complications included vitreous hemorrhage in nine eyes (37.5%), arterial occlusion in two (8.3%), cyclitic membrane possibly secondary to ischemia and tractional retinal detachment in one patient (4.2%), chorioretinal atrophy in three (12.5%) patients, and neovascular glaucoma in one eye (4.2%). In eight (33.3%) patients, no complication happened. Globe salvage was achieved in 62.5% of the cases. The success rate for naive patients was 84%. Sixty-seven percent of the cases received transpupillary thermotherapy and cryotherapy before IAC.

Conclusions:

Intra-ophthalmic artery melphalan is an effective treatment for advanced cases of retinoblastoma, with a reasonable level of success. In the short follow up period of this study, it appears that the primary cases showed better results in the control of tumor.

Conservative treatment modalities in retinoblastoma

Retinoblastoma is the most common primary intraocular malignancy of childhood. A potentially curable cancer, its treatment has improved significantly over the last few decades. The purpose of this article is to review the literature on various conservative treatment modalities available for the treatment of retinoblastoma and their effectiveness, when used alone or in combination. Pubmed, Medline, Embase, and the Cochrane library were searched through 2012 for published peer reviewed data on conservative treatment modalities for retinoblastoma. Various studies show that while enucleation remains the standard of care for advanced intraocular tumors, conservative modalities that can result in globe salvage and preservation of useful vision are being increasingly employed. Such modalities include systemic chemotherapy, focal consolidation with transpupillary thermotherapy, laser photocoagulation and cryotherapy, plaque brachytherapy, and delivery of local chemotherapy using subconjunctival, sub-tenon, or intra-arterial routes. When used alone or in combination, these treatment modalities can help in avoidance of external beam radiotherapy or enucleation, thus reducing the potential for long-term side effects, while salvaging useful vision. Radioactive plaque brachytherapy has an established role in selected patients with intraocular retinoblastoma. Local injections of chemotherapeutic agents via the sub-tenon or sub-conjunctival route have been used with varying degrees of success, usually as an adjunct to systemic chemotherapy. Intra-arterial ophthalmic artery delivery of melphalan has shown promising results. It is important to recognize that today, several treatment options are available that can obviate the need for enucleation, and cure the cancer with preservation of functional vision. A thorough knowledge and understanding of these conservative treatment modalities is essential for appropriate management.

Long-term retinoblastoma follow-up with or without general anaesthesia

BACKGROUND

Children with treated retinoblastoma undergo frequent examinations to monitor for recurrent or new tumours. Examinations under anaesthesia allow a more complete examination in younger children, however they are stressful for the family, subject the child to medical risk and consume resources. The risk of recurrent or new tumours declines with age and it is common practice to examine older children without general anaesthesia. There are no studies on the safety and cost effectiveness of this practice, or guidelines on when examination without anaesthesia (EWA) can be safely commenced.

PROCEDURE

Retrospective case note review of 128 sequential patients treated for retinoblastoma in a national referral centre over 10 years.

RESULTS

Following exclusions, 113 eyes of 84 children were analysed. The mean age at diagnosis was 20 months (range birth to 71 months). There were 55 unilateral and 29 bilateral cases. The mean follow-up was 77.7 months (range 12-178 months). EWA was commenced at a mean age of 53 months (range 12-98 months). The age of conversion to EWA was largely dependent on child cooperation and disease activity. Tumour activity was detected on EWA in one child at the age of 86 months, 9 months after the last active treatment and treated successfully.

CONCLUSIONS

Examination without general anaesthesia does not appear to expose children to an increased risk of undetected tumour growth. This study highlights the important factors to be considered when deciding a safe time to commence EWA.

Establishment of the relationship between tumor size and range of histological involvement to evaluate the rationality of current retinoblastoma management

Purpose

To determine whether tumor size correlates with histopathological involvement and hence evaluate the rationality of conservative treatment for retinoblastoma.

Methods

We retrospectively studied 221 patients (221 eyes) treated for retinoblastoma with enucleation in the Zhongshan Ophthalmic Center of Sun Yat-sen University, China, from October 1995 to December 2004. Histopathological data included involvement of the anterior chamber, sclera, choroids, and optic nerve. Tumor size was measured by B-ultrasound examination.

Results

Tumor invasion of the optic nerve correlated with the Reese-Ellsworth (R-E) staging system and the International Classification for Retinoblastoma (ICRB): optic nerve involvement was significantly more frequent in R-E stage V (P = 0.009) and ICRB Group E (P = 0.002) cases. However, 19.1% of patients with R-E stage I, II and III, and 16.7% of patients with ICRB Group B and C disease showed histopathological involvement of the postlaminar optic nerve. Extraocular involvement was observed in 17.7% of tumors ≤15 mm in diameter. Tumors >15 mm in diameter showed greater extraocular involvement, including the optic nerve (P = 0.000) and sclera (P = 0.032), than tumors ≤15 mm in diameter. Postlaminar optic nerve invasion was observed in 19.6% of tumors ≤10 mm in thickness. Tumors >10 mm in thickness had sclera involvement more frequently than tumors ≤10 mm in thickness (P = 0.029). Postlaminar optic nerve invasion was noted in 17.1% of patients with tumors ≤15 mm in diameter and ≤10 mm in thickness.

Conclusions

Medium-sized retinoblastomas frequently invade outside the globe. Thus, indications for conservative treatment need improvement.

Survey on the management of orbital and intraocular tumors among oculofacial surgeons in the Asia-Pacific region

A web-based anonymous survey was performed to assess the common practices of oculofacial surgeons in the management of orbital and intraocular tumors in the Asia-Pacific region. The questionnaire comprised a series of questions covering controversial topics sent via email to 131 oculofacial surgeons across 14 countries in the Asia-Pacific region. A total response rate of 61.7 % was achieved from May to December 2012. The most common benign orbital tumor was cavernous hemangioma (39.6 %) and the most common malignant orbital tumor was lymphoma (85.7 %). 40 % of surgeons recommended orbital radiation, for which the most common indications were thyroid eye disease (70.0 %) and malignancy (30.0 %). The most common orbitotomy approach was lateral (79.2 %). Most surgeons (87.1 %) offered enucleation for retinoblastoma, but there was also a significant proportion that offered chemoreduction with transpupillary thermotherapy or cryotherapy (58.1 %). Fewer surgeons offered brachytherapy (16.1 %) and intra-arterial chemotherapy (6.5 %). When performing enucleation for retinoblastoma, 81.8 % of surgeons performed a primary orbital implant placement. The most preferred type of implant was silicone/acrylic (90.2, 90.2 and 87.8 % for elderly, adults and children, respectively). The majority of surgeons used donor sclera (57.5 %) or no wrapping material at all (32.5 %). Almost all surgeons (95.1 %) did not drill and peg the implant for motility. We report the results of the first survey of oculofacial surgeons in the Asia-Pacific region on the management of intraocular and orbital tumors. In comparison with previous surveys performed in the USA and the UK, we found the practice patterns of the Asia-Pacific surgeons to be comparable.

Retinoblastoma and treatment: A current evaluation of advanced therapy

Retinoblastoma is the most common primary childhood ocular tumor, affecting nearly 3.5 per million children worldwide. A mutation in the RB1 gene, which presents as either germline or sporadic, along with additional mutational events, promote neoplastic growth in the retina. Fortunately, current treatment protocols result in success rates approaching 99% at specialized centers, with many children maintaining useful vision. Overall, treatment is guided by aggressiveness and size, and is classified by systems such as the Reese-Ellsworth System and the International Classification of Retinoblastoma. Due to advances in chemotherapy protocols combined with use of focal laser consolidation, treatment paradigms have shifted from enucleation to external beam radiation therapy to chemotherapy as globe-salvaging therapies. Smaller, less complex tumors may be controlled by plaque radiotherapy or focal laser ablative therapy. However, larger and more complex tumors, such as those that have vitreous or subretinal seeding, require methods of chemoreduction combined with focal consolidation to yield better outcomes. Standard chemotherapy protocols utilize vincristine, etoposide, and carboplatin with or without cyclophosphamide. Finally, there has been a recent push in local treatments for retinoblastoma to minimize systemic toxicities. These modalities include intravitreal or subconjunctival injections and more recently, direct chemotherapy administration into the ophthalmic artery. As a result, enucleation is used less often, but remains an important treatment for the most aggressive, refractory cases. The advancement of retinoblastoma treatment looks promising; however, worldwide access to these treatments and the lack of long-term follow-up of new local treatment modalities constitute current and future challenges.

Salvage/adjuvant brachytherapy after ophthalmic artery chemosurgery for intraocular retinoblastoma

PURPOSE

To evaluate the efficacy and toxicity of brachytherapy after ophthalmic artery chemosurgery (OAC) for retinoblastoma.

METHODS AND MATERIALS

This was a single-arm, retrospective study of 15 eyes in 15 patients treated with OAC followed by brachytherapy at (blinded institution) between May 1, 2006, and December 31, 2012, with a median 19 months' follow-up from plaque insertion. Outcome measurements included patient and ocular survival, visual function, and retinal toxicity measured by electroretinogram (ERG).

RESULTS

Brachytherapy was used as adjuvant treatment in 2 eyes and as salvage therapy in 13 eyes of which 12 had localized vitreous seeding. No patients developed metastasis or died of retinoblastoma. The Kaplan-Meier estimate of ocular survival was 79.4% (95% confidence interval 48.7%-92.8%) at 18 months. Three eyes were enucleated, and an additional 6 eyes developed out-of-target volume recurrences, which were controlled with additional treatments. Patients with an ocular complication had a mean interval between last OAC and plaque of 2.5 months (SD 2.3 months), which was statistically less (P=.045) than patients without ocular complication who had a mean interval between last OAC and plaque of 6.5 months (SD 4.4 months). ERG responses from pre- versus postplaque were unchanged or improved in more than half the eyes.

CONCLUSIONS

Brachytherapy following OAC is effective, even in the presence of vitreous seeding; the majority of eyes maintained stable or improved retinal function following treatment, as assessed by ERG.