A 20-year audit of retinoblastoma treatment outcomes

Conservative treatment using laser diode and systemic chemotherapy for early-stage bilateral retinoblastoma: A 14-year prospective cohort study

BACKGROUND

Solid evidence of the safety and effectiveness of retinoblastoma (RB) conservative treatment using thermotherapy and systemic chemotherapy with long-term follow-up is scarce, especially in low-resource countries.

AIMS

This study examined the outcomes of this treatment and associated predictors in Vietnam to strengthen the current RB treatment protocol focusing on preserving eye and vision in low-resource settings.

METHODS AND RESULTS

A prospective cohort study was conducted at Ho Chi Minh City Eye Hospital in Vietnam from 2005 to 2019. All eligible patients with bilateral RB (one eye already removed and another eye classified as group A or B) and without previous treatment were recruited. All patients received thermotherapy and six cycles of systemic three-agent chemotherapy repeated every 4 weeks. A standardized questionnaire was used to collect information on study participants' age, symptoms, tumor characteristics, treatment, and outcomes. Among 50 eyes of all 50 patients with a median age of 9 (4-20) months, 34 eyes were in group B (68%). The median follow-up time was 60 (60-84) months. All 139 preserved tumors regressed mostly to type 4 (70.4%) and type 3 (23.7%) scars. Kaplan-Meier analysis found the overall globe-salvage rate at 5 years of 91.9% (95% CI: 80.1%-97.7%). Most eyes (41/50, 82%, 95% CI: 69.2%-90.2%) had a final visual acuity ≥0.1. The visual acuity is higher when tumors regressed to a type 4 scar (p = .007, AOR = 8.098, 95% CI: 1.79-36.53) which also shows less enucleation than a type 3 scar (p = .002, AOR = 0.06, 95% CI: 0.01-0.37%). Gender effect on visual acuity after treatment was significant and may be due to discrimination. No major complications were recorded.

CONCLUSION

Conservative treatment of early-stage RB is safe and effective. Long-term, thorough follow-ups of patients post-treatment are needed. The regression patterns of scars could be a useful indicator of treatment failure.

Treatment adherence in retinoblastoma: A retro-prospective cohort study in Ivory Coast and the Democratic Republic of Congo

BACKGROUND

In high-income countries, retinoblastoma is curable in more than 95% of cases, whereas in low-income countries, mortality remains high, especially when the diagnosis is made late or the treatment is discontinued.

AIMS

To determine the factors associated with adherence to the treatment of retinoblastoma in the Ivory Coast and the Democratic Republic of Congo (DRC).

METHODS AND RESULTS

A retro-prospective cohort study was carried out. Data were collected from patient folders and follow-up records of parents.

RESULTS

A total of 175 children with retinoblastoma were registered from January 2013 to December 2015. Seventy-six children (43%) were 5 years old and above. Care costs were covered by families in 86.9% of cases. Chemotherapy refusal was recorded in 39 cases (22.3%), and enucleation refusal was recorded in 79 cases (45.1%). After 36 months of follow-up, we recorded 16.6% deaths, 27.4% treatment dropouts, and 18.3% loss to follow-up after treatment. The commonest cause for enucleation refusal was fear of infirmity, while chemotherapy refusal and absconding treatment were due to financial constraints.

CONCLUSION

Poor adherence to retinoblastoma management was due to financial constraints, and a lack of knowledge of the disease and its treatment. Family psychosocial support is needed to improve this condition.

Epidemiology of Eye Cancer in Cali, Colombia: A 55-Year Study

PURPOSE

To describe the epidemiology, incidence, mortality and survival of ocular cancer in Cali between 1962 and 2019.

METHODS

Ecological population-based study analyzing data of incidence, mortality, and 5-years survival of malignant ocular tumors from the Populational Cancer Registry of Cali between 1962 and 2019.

RESULTS

Between 1962 and 2019, 586 ocular tumors were found, 50.5% occurred in females, the mean age at diagnosis was 45 years (standard deviation = 25), 70.3% of ocular malignancies occurred in >14 years. The average annual incidence rate was 7.8 per million for male and 6.9 per million for females. Retinoblastoma (21%), squamous cell carcinoma (20%), melanoma (16%) and lymphoma (8%) were the most common neoplasm. In those <15 years, the most frequent malignant tumors were retinoblastomas (85.7%), followed by non-specified malignant neoplasm (NOS, 7.9%), and rhabdomyosarcoma (3.6%). In those >14 years, there were NOS (30%), followed by squamous cell carcinomas (28%), melanomas (23%), and lymphomas (9.7%). Conjunctiva (38.2%), retina (21%) and orbit (10%) constituted the majority of anatomical sites of ocular tumors. The survival rate was about 83.2% and mortality did not show a decreasing trend over time (p > .05).

CONCLUSIONS

The incidence of ocular cancer in Cali has a slightly increasing trend, with stable behavior in the last decades. Squamous cell carcinoma, retinoblastoma, melanoma and lymphoma are the most frequent ocular cancers, with being retinoblastoma more frequent than melanoma. In general, ocular cancer had good survival rates in Cali.

Causes of death and survival analysis for patients with retinoblastoma in Jordan

Purpose

To analyze causes and prognostic factors for death among Retinoblastoma (Rb) patients treated at a single specialized tertiary cancer center in Jordan.

Methods

We reviewed the mortality causes for all Rb patients who have been treated at the King Hussein Cancer Center between 2003 and 2019 and were followed for at least 3 years after diagnosis. The main outcome measures included demographics, laterality, tumor stage, treatment modalities, metastasis, survival, and causes of death.

Results

Twenty-four (5%) of the 478 patients died from retinoblastoma and 5-year survival was 94%. The mean age at diagnosis was 15 months (median, 18 months; range, 4-38 months); eight (33%) received diagnoses within the first year of life. Eleven (46%) were boys, 16 (67%) had bilateral disease, and 3 (13%) had a positive family history. The stage for the worst eye was C for 1 (4%) patient, D in 6 (25%) patients, and E (T3) in 15 (63%) patients. Two patients had extraocular Rb at diagnosis, and four of the patients who had intraocular Rb at diagnosis refused treatment and then came back with extraocular Rb. In total, extraocular disease was encountered in six eyes (six patients). After a 120-month median follow-up period, 24 patients (5%) died of second neoplasms (n = 3) or metastases (n = 21). Significant predictive factors for metastasis and death included advanced IIRC tumor stage (p < 0.0001), the presence of high-risk pathological features in the enucleated eyes (p = 0.013), parental refusal of the recommended primary treatment plan (p < 0.0001), and extraocular extension (p < 0.0001).

Conclusion

The 5-year survival rates of Rb patients in Jordan are as high as those in high-income countries. However, 5% are still dying from metastatic disease, prompting the need for awareness campaigns to educate the public about the high cure rates and to prevent treatment abandonment.

Genetics in ophthalmology: molecular blueprints of retinoblastoma

This review presents current knowledge on the molecular biology of retinoblastoma (RB). Retinoblastoma is an intraocular tumor with hereditary and sporadic forms. 8,000 new cases of this ocular malignancy of the developing retina are diagnosed each year worldwide. The major gene responsible for retinoblastoma is RB1, and it harbors a large spectrum of pathogenic variants. Tumorigenesis begins with mutations that cause RB1 biallelic inactivation preventing the production of functional pRB proteins. Depending on the type of mutation the penetrance of RB is different. However, in small percent of tumors additional genes may be required, such as MYCN, BCOR and CREBBP. Additionally, epigenetic changes contribute to the progression of retinoblastoma as well. Besides its role in the cell cycle, pRB plays many additional roles, it regulates the nucleosome structure, participates in apoptosis, DNA replication, cellular senescence, differentiation, DNA repair and angiogenesis. Notably, pRB has an important role as a modulator of chromatin remodeling. In recent years high-throughput techniques are becoming essential for credible biomarker identification and patient management improvement. In spite of remarkable advances in retinoblastoma therapy, primarily in high-income countries, our understanding of retinoblastoma and its specific genetics still needs further clarification in order to predict the course of this disease and improve therapy. One such approach is the tumor free DNA that can be obtained from the anterior segment of the eye and be useful in diagnostics and prognostics.

Utility of bone marrow examination in retinoblastoma and their correlation with hematological features

Retinoblastoma makes up about 3% of all childhood malignancies. The frequency of metastatic retinoblastoma ranges from 4.8 to 11%. Assessing the bone marrow status of newly diagnosed patients is crucial because of the advantages of autologous bone marrow transplants for high-risk patients. This study aimed to determine the utility of bone marrow examination in cases of retinoblastoma and its correlation with hematological findings. This retrospective study was conducted at the Department of Pathology, King George's Medical University, Lucknow, India. A total of 34 cases of retinoblastoma with bone marrow examination were included in the study. Bone marrow infiltration was present in 17.65% (6/34) cases of retinoblastoma. Bone marrow aspirate myelogram showed that marrow metastasis in retinoblastoma was significantly linked with a reduced percentage of total myeloid cells (p=0.001) and segmented cells (p=0.006). The present study demonstrated that 15% (3/20) of retinoblastoma patients previously classified as nonmetastatic before bone marrow examination (stages I to III based on histology, imaging, and bone scan) had bone marrow metastases following bone marrow examination and were upgraded to stage IV. To conclude, a diligent and exhaustive search for metastatic cells in bone marrow is advised if the myelogram shows a reduced percentage of total myeloid and segmented cells. All stage II and stage III cases of retinoblastoma must undergo bone marrow examination for early metastasis detection, as it may result in an upgrade to stage IV disease, impacting the prognosis and necessitating distinct treatment modalities.

Piperlongumine inhibits proliferation and oncogenic MYCN expression in chemoresistant metastatic retinoblastoma cells directly and through extracellular vesicles

Ocular retinoblastoma malignancies, which develop into metastatic phenotypes, result in poor prognosis and survival for infant and child patients. To improve the prognosis of metastatic retinoblastoma, it is important to identify novel compounds with less toxic side effects and higher therapeutic efficacy compared to existing chemotherapeutics. Piperlongumine (PL), a neuroprotective, plant-derived compound has been explored for its anticancer activities both in vitro and in vivo. Here, we analyze the potential efficacy of PL for metastatic retinoblastoma cell treatment. Our data reveal that PL treatment significantly inhibits cell proliferation in metastatic retinoblastoma Y79 cells compared to the commonly used retinoblastoma chemotherapeutic drugs carboplatin, etoposide, and vincristine. PL treatment also significantly increases cell death compared to treatment with other chemotherapeutic drugs. PL-induced cell-death signaling was associated with significantly higher caspase 3/7 activities and greater loss of mitochondrial membrane potential. PL was also internalized into Y79 cells with an estimated concentration of 0.310pM and expression analysis revealed reduced MYCN oncogene levels. We next examined extracellular vesicles derived from PL-treated Y79 cells. Extracellular vesicles in other cancers are pro-oncogenic, mediating systemic toxicities via the encapsulation of chemotherapeutic drugs. Within metastatic Y79 EV samples, an estimated PL concentration of 0.026pM was detected. PL treatment significantly downregulated Y79 EV cargo of the oncogene MYCN transcript. Interestingly, non-PL-treated Y79 cells incubated with EVs from PL-treated cells exhibited significantly reduced cell growth. These findings indicate that in metastatic Y79 cells, PL exhibits potent anti-proliferation effects and oncogene downregulation. Importantly, PL is also incorporated into extracellular vesicles released from treated metastatic cells with measurable anti-cancer effects on target cells at a distance from the site of primary treatment. The use of PL in the treatment of metastatic retinoblastoma may reduce primary tumor proliferation and inhibit metastatic cancer activity systemically via extracellular vesicle circulation.

Referral patterns for retinoblastoma patients in Ethiopia

BACKGROUND

Increased lag time between the onset of symptoms and treatment of retinoblastoma (RB) is one of the factors contributing to delay in diagnosis. The aim of this study was to understand the referral patterns and lag times for RB patients who were treated at Menelik II Hospital in Addis Ababa, Ethiopia.

METHOD

A single-center, cross- sectional study was conducted in January 2018. All new patients with a confirmed RB diagnosis who had presented to Menelik II Hospital from May 2015 to May 2017 were eligible. A questionnaire developed by the research team was administered to the patient's caregiver by phone.

RESULTS

Thirty-eight patients were included in the study and completed the phone survey. Twenty-nine patients (76.3%) delayed seeing a health care provider for ≥ 3 months from the onset of symptoms, with the most common reason being the belief that it was not a problem (96.5%), followed by 73% saying it was too expensive. The majority of patients (37/38, 97.4%) visited at least 1 additional health care facility prior to reaching a RB treatment facility. The mean overall lag time from noticing the first symptom to treatment was 14.31 (range 0.25-62.25) months.

CONCLUSION

Lack of knowledge and cost are major barriers to patients first seeking care for RB symptoms. Cost and travel distance are major barriers to seeing referred providers and receiving definitive treatment. Delays in care may be alleviated by public education, early screening, and public assistance programs.

Polyester 5-0 suture for porous implant placement after retinoblastoma enucleation: analysis of 120 sockets

BACKGROUND

Techniques used to suture the rectus muscle to the implant can influence the implant-related complications which is still a major problem following retinoblastoma enucleation. The goals of this work were to report the efficacy among patients with retinoblastoma who underwent enucleation followed by porous implant placement with the rectus muscles sutured with 5-0 polyester suture.

METHODS

This was a retrospective study of consecutive patients with retinoblastoma who underwent primary enucleation and porous implant placement with the rectus muscles tagged and sutured to the implant with polyester 5-0 suture. All the patients were followed up for a minimum of 2 years. The main outcome measure was implant exposure. The secondary efficacy measures were other implant-related complications.

RESULTS

Between May 2016 and December 2018, a total of 120 patients (120 eyes) underwent primary enucleation and porous implant placement were included. Postoperatively, 10/120 (8.3%) eyes developed exposure or conjunctival granuloma. Exposure was the most common postoperative complication (7/10, 70.0%). There were no cases of implant extrusion, migration, or infection.

CONCLUSIONS

Polyester 5-0 sutures are successful in patients with retinoblastoma who underwent enucleation followed by porous implant placement. Complications are minimal. Polyester 5-0 sutures were not associated with unacceptable complications in this pediatric population.

Targeted chemotherapy in retinoblastoma: A step forward from patient survival to globe survival

BACKGROUND/ OBJECTIVES

Despite being the most common intraocular malignancy in childhood, there is a substantial disparity between developing and developed countries in terms of patient and globe survival in retinoblastoma (Rb). The current study intends to determine patient and globe survival before and after the introduction of the new targeted treatment modalities in a developing country.

METHODS

Medical records of 350 patients (516 eyes) with retinoblastoma referred to a tertiary referral center for Rb in Tehran, Iran, were reviewed. In order to compare patient and globe survival before and after the availability of the new treatment modalities, including intra-arterial and intravitreal chemotherapy, the patients were divided into group 1 (2001-2007) and group 2 (2008-2018) based on the calendar period of diagnosis.

RESULTS

Two-hundred-twenty-three eyes of 149 patients and 293 eyes of 201 patients were categorized into groups 1 and 2, respectively. The 5-year patient survival was 97% across the current survey, and the overall survival rate was 96% in group 1 and 99% in group 2 (P = 0.08). Overall, 50% of eyes with retinoblastoma underwent enucleation, which was the primary in 63% (116/184) of the unilateral and 30% (99/322) of the bilateral cases. Primary enucleation was significantly lower in group 2 (35%) in contrast to group 1 (50%) (P < 0.001). In addition, globe survival improved significantly in the International Classification of Retinoblastoma Groups D (17% in group 1 vs. 66% in group 2, P < 0.001) and E (1% in group 1 vs. 23% in group 2 P < 0.001) during the two timelines. In enucleated eyes, despite the increased rate of prelaminar involvement in group 2 (13% vs. 2% in group 1, P = 0.003), the rate of high-risk histopathologic findings was similar between the two groups.

CONCLUSION

Similar to developed countries, the application of new targeted treatment modalities, including intra-arterial and intravitreal chemotherapy, has been associated with significantly improved globe survival in Rb patients. However, it should be noted that even with the availability of these novel treatment options, the decision for on-time enucleation should not be deferred.

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

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

Retinoblastoma in Adults: Clinical Features, Gene Mutations and Treatment Outcomes: A Study of Six Cases

Purpose

To report six Asian adult patients with retinoblastoma (RB).

Design

Retrospective and observational small case series.

Participants

Six patients with a white dome-shaped tumor of the retina were evaluated from May 10, 1995, to September 10, 2021.

Main Outcome Measures

Initial tumor and associated fundus features, pathology, gene mutation, treatment, tumor course on follow-up, and salvage globe outcome.

Results

The six affected Asian patients consisted of three men and three women. The mean age at the time of diagnosis was 36.5 years (median: 31 years, range: 20-55 years). All patients were unilateral. In all cases, the tumors were white, dome-shaped, with full-thickness retinal involvement, and mushroom-like protrusions into the vitreous cavity. The mean tumor thickness measured by ultrasonography was 4.5 mm (median: 3.2 mm, range: 3.2-6.8 mm). Associated characteristic symptoms included dilated retinal feeding artery and draining vein (100%), surrounding subretinal infiltration (83%), exudative retinal detachment (83%), and vitreous seeds (67%). Local tumor resection was performed in three patients, I-125 plaque brachytherapy combined with transpupillary thermotherapy (TTT) and intravitreous injection of melphalan (combination treatment) in one patient, I-125 plaque brachytherapy in two patients, and enucleation in one (20%) patient. RB1 gene testing was carried out on four patients and pathological diagnosis on five patients. Genetic analysis revealed that the RB1 mutation was a mosaic c.709dupG (p.Glu237GlyfsTer4) duplication in one patient, a mosaic c.763C>T(p.Arg255Ter) mutation in another patient, while the remaining two patients were RB1 negative. At the end of the follow-up, none of the patients had developed tumor-related metastasis or died. The findings were consistent in all patients who had an adequate follow-up. This study focused on this rare lesion to distinguish it from other intraocular white lesions in adults, including choroidal osteoma, vitreoretinal lymphoma, and retinal capillary hemangioma, all of which are different clinical entities.

Conclusion

In adults, RB is typically a white, full-thickness retinal mass that is unilateral, often combining with retinal feeding vessels, subretinal infiltration, and vitreous seeds. Genetic studies on adult-onset RB are essential and still require elucidation. Despite RB being a malignant tumor, patient survival was minimally affected.

Improving Medical Students’ Awareness About Retinoblastoma: A Practical Strategy

Background

Eye salvage and survival for patients with retinoblastoma (RB) can be improved by enhancement of early diagnosis. This study aims to investigate the impact of modifying the teaching curriculum for medical students about awareness of this condition.

Methods

Medical students completed a questionnaire about RB, preluded by a photograph of a child with leukocoria. Participants were divided into group A (138 participants) and group B (151 participants) who are medical students who have completed the ophthalmology rotation before and after implementing modifications on teaching curriculum that focuses on the red flags of RB consecutively.

Results

Most participants considered leukocoria an abnormal sign. Group A had significantly lower knowledge about diagnosis for RB (P=0.0001). Participants scored higher in group B for the critical questions, such as knowing that RB is a fatal disease (P=0.041) that needs urgent treatment (P=0.042). Only three (2%) students adopted the “watch and wait” strategy in group B, compared to 16 (12%) in group A (P=0.0013). Overall, proficiency score (≥90%) was achieved by 12 (8%) students in group B, but only three (2%) students in group A. Only 41 (27%) students in group B, compared to 90 (65%) students in group A, failed to obtain a sufficiency score (≥70%) in the questionnaire.

Conclusion

Modifying the teaching curriculum of the ophthalmology rotation with an intensified focus on awareness of the life-threatening condition retinoblastoma improved medical students’ knowledge of this malignancy. This intervention is one of the modalities that can lead to a reduction in diagnosis and referral delays and improvement in outcome and survival.

Distantly Metastatic Retinoblastoma to Soft Tissue and Bone: A Challenging Diagnosis Highlighting the Utility of CRX

Distant metastasis of retinoblastoma to sites outside the central nervous system is rare; such cases may present years following primary treatment. Diagnosis may be difficult given the rarity of such events and considerable histologic mimics. We describe the clinicopathologic features of 6 cases of metastatic retinoblastoma to distant bone and soft tissue sites from 2 large academic centers. Patients were 3 female and 3 male children; median age was 9.5 years (range: 5 to 15 y) with a mean interval from primary disease diagnosis of 8.0 years (range: 0.75 to 14 y). Metastasis to bones of the lower extremities was most common, occurring in 4 of 6 cases. Tumors showed typical histologic features of retinoblastoma, with sheets of primitive round cells with minimal cytoplasm and indistinct nucleoli; however, characteristic Flexner-Wintersteiner rosettes were absent. A subset of cases demonstrated an alveolar growth pattern, and 2 cases showed higher grade cytology with nuclear anaplasia and prominent nucleoli. Immunohistochemistry for CRX and RB1 showed uniform positivity and loss of expression, respectively. Metastatic retinoblastoma outside the central nervous system may present following long disease-free intervals. Immunohistochemistry for CRX is helpful to confirm this challenging diagnosis.

Current Indications of Secondary Enucleation in Retinoblastoma Management: A Position Paper on Behalf of the European Retinoblastoma Group (EURbG)

Simple Summary

Although secondary enucleation (SE) is the treatment of choice for retinoblastoma eyes that did not respond favorably to conservative therapies, clear criteria for its indication are, however, currently missing. In this position paper on behalf of the European Retinoblastoma Group (EURbG), we discuss the available literature on SE, including its influence on metastases rate and survival, and propose guidelines to assist decision-making to interrupt eye-preserving therapies depending on the availabilities of advanced diagnostic and therapeutic modalities. Absolute indications to SE may be restricted to eyes with refractory tumor activity resisting all salvage treatments or eyes under apparent tumor control but no visual potential and irreducible complications. In contrast, eyes with an obscured optic nerve head and/or ocular complications amenable to specific surgical or medical management can be considered relative indications, provided that appropriate follow-up can be implemented and that parents are fully aware of a residual risk.

Abstract

Secondary enucleation (SE) puts an irreversible end to eye-preserving therapies, whenever their prolongation is expected to violate the presumed state of metastatic grace. At present, it must be acknowledged that clear criteria for SE are missing, leading to empiric and subjective indications commonly related to disease progression or relapse, disease persistence masking the optic nerve head or treatment-related complications obscuring the fundus view. This absence of evidence-based consensus regarding SE is explained by the continuously moving frontiers of the conservative management as a result of diagnostic and therapeutic advances, as well as by the lack of studies sufficiently powered to accurately stratify the risk of metastasis in conservatively treated patients. In this position paper of the European Retinoblastoma Group (EURbG), we give an overview of the progressive shift in the indications for SE over the past decades and propose guidelines to assist decision-making with respect to when SE becomes imperative or recommended, with corresponding absolute and relative SE indications. Further studies and validation of biologic markers correlated with the risk of metastasis are expected to set more precisely the frontiers of conservative management and thus consensual criteria for SE in the future.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

DISCUSSION

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

Adjuvant therapy of histopathological risk factors of retinoblastoma in Europe: A survey by the European Retinoblastoma Group (EURbG)

INTRODUCTION

Advanced intraocular retinoblastoma can be cured by enucleation, but spread of retinoblastoma cells beyond the natural limits of the eye is related to a high mortality. Adjuvant therapy after enucleation has been shown to prevent metastasis in children with risk factors for extraocular retinoblastoma. However, histological criteria and adjuvant treatment regimens vary and there is no unifying consensus on the optimal choice of treatment.

METHOD

Data on guidelines for adjuvant treatment in European retinoblastoma referral centres were collected in an online survey among all members of the European Retinoblastoma Group (EURbG) network. Extended information was gathered via personal email communication.

RESULTS

Data were collected from 26 centres in 17 countries. Guidelines for adjuvant treatment were in place at 92.3% of retinoblastoma centres. There was a consensus on indication for and intensity of adjuvant treatment among more than 80% of all centres. The majority of centres use no adjuvant treatment for isolated focal choroidal invasion or prelaminar optic nerve invasion. Patients with massive choroidal invasion or postlaminar optic nerve invasion receive adjuvant chemotherapy, while microscopic invasion of the resection margin of the optic nerve or extension through the sclera are treated with combined chemo- and radiotherapy.

CONCLUSION

Indications and adjuvant treatment regimens in European retinoblastoma referral centres are similar but not uniform. Further biomarkers in addition to histopathological risk factors could improve treatment stratification. The high consensus in European centres is an excellent foundation for a common European study with prospective validation of new biomarkers.

Fibroblasts from Retinoblastoma Patients Show Radiosensitivity Linked to Abnormal Localization of the ATM Protein

PURPOSE/AIM OF THE STUDY

Retinoblastoma (Rb) is a rare form of pediatric cancer that develops from retina cells. Bilateral and some unilateral forms of Rb are associated with heterozygous germline mutations of the (retinoblastoma 1) RB1 gene. RB1 mutations are also associated with a significant risk of secondary malignancy like head and neck tumors. Hence, to date, even if Rb patients are less subjected to radiotherapy to treat their primary ocular tumors, their healthy tissues may be exposed to significant doses of ionizing radiation during the treatment against their secondary malignancies with a significant risk of adverse tissue reactions (radiosensitivity) and/or radiation-induced cancer (radiosusceptibility). However, the biological role of the Rb protein in response to radiation remains misunderstood. Since the ataxia telangiectasia mutated (ATM) protein is a key protein of radiation response and since untransformed skin fibroblasts are a current model to quantify cellular radiosensitivity, we investigated here for the first time the functionality of the ATM-dependent signaling and repair pathway of the radiation-induced DNA double-strand breaks (DSB) in irradiated skin fibroblasts derived from Rb patients.

MATERIALS AND METHODS

The major biomarkers of the DSB repair and signaling, namely clonogenic cell survival, micronuclei, nuclear foci of the phosphorylated forms of the X variant of the H2A histone (γH2AX), the phosphorylated forms of the ATM protein (pATM) and the meiotic recombination 11 nuclease (MRE11) were assessed in untransformed skin fibroblasts derived from three Rb patients.

RESULTS

Skin fibroblasts from Rb patients showed significant cellular radiosensitivity, incomplete DSB recognition, delay in the ATM nucleo-shuttling and exacerbated MRE11 nuclease activity. Treatment with statin and bisphosphonates led to significant complementation of these impairments.

CONCLUSIONS

Our findings strongly suggest the involvement of the ATM kinase in the radiosensitivity/radiosusceptibility phenotype observed in Rb cases.