Conservative therapy in intraocular retinoblastoma: response/recurrence rate

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.

Intravenous Chemotherapy for Retinoblastoma in the Era of Intravitreal Chemotherapy: A Systematic Review

Purpose

The published data on ocular survival following intravenous chemotherapy of retinoblastoma (RB) seems to be skewed by evolving practice patterns induced by use of intravitreal chemotherapy (iVitc). We aimed to explore potential role of iVitc for vitreous seeding for patients treated with intravenous chemotherapy (IVC).

Methods

A literature search was performed to identify cases of RB treated with primary IVC prior to advent of iVitc by various search engines (PubMed, Medline, and Google) from 1992 to 2018. Studies were excluded if number of cases were less than 40 or lacked data related to type of recurrence and its treatment. Rates and patterns of recurrence and its management were categorized.

Results

Out of 15 studies identified, only 10 studies (797 eyes) met the inclusion criteria. The mean age at presentation was 15.3 months (range 0-192.8 months). Unilateral cases represented 25% of the cohort. The ocular survival rate with primary IVC was 63% (500/797 eyes). Of the 297 eyes (37%) that failed IVC therapy, additional 99 eyes could be salvaged with EBRT (599/797 eyes, 75%). Remaining 198 eyes were enucleated (198/797 eyes 25%). K-M survival analysis could not be done due lack of sufficient data. Recurrences that occurred (mean 12.2 months) after completion of primary IVC included relapse of retinal tumor (143 eyes [48%]), vitreous seeding (73 eyes [25%]), subretinal seeding (49 eyes [16%]), or any combination (103 eyes [35%]). Out of 73 eyes with vitreous seeding, additional 66 eyes (90%) would have been salvaged with iVitc, potentially improving ocular survival rates to 71% (500 + 66/797).

Conclusions

Evolving practice patterns of RB treatment have unfavorably skewed published ocular survival rates following IVC. With incorporation of iVitc, the ocular survival rates with IVC can be potentially improved to be non-inferior to those achieved with intra-arterial chemotherapy.

Effect of Intravenous Chemotherapy Regimen on Globe Salvage Success Rates for Retinoblastoma Based on Disease Class-A Meta-Analysis

Simple Summary

Intravenous chemoreduction (IVCRD) has been the standard of care for treatment of retinoblastoma (RB). Since survival rates exceed 95–98%, the goals of treatment have now shifted to emphasize eye salvage and vision preservation in addition to patient survival. Consequently, there has been a shift towards combining standard IVCRD with intravitreal chemotherapy or altogether replacing IVCRD with intra-arterial chemotherapy. As more data from intravitreal chemotherapy and intra-arterial chemotherapy are being published, there are claims of improved globe salvage rates resulting in more widespread use of these newer treatment modalities. However, there are no published randomized controlled trials comparing these to IVCRD head-to-head. To evaluate the relative efficacy of these new therapies, it is critical to determine the true success rates of IVCRD regimens alone. Therefore, it is both timely and essential to determine the baseline IVCRD success rates so that an evidence-based assessment of new and emerging therapies can be determined.

Abstract

To evaluate the relative efficacy of novel retinoblastoma treatments, eye classification-specific success rates for current standard-of-care intravenous chemotherapy regimens must be known. This meta-analysis included studies if: (1) patients received intravenous chemotherapy for retinoblastoma, (2) globe salvage data was reported, (3) only intravenous chemoreduction (with/without local consolidation) was used. The outcome measure was globe salvage success without need for salvage radiotherapy, subdivided by disease classification and chemotherapy regimen. Data from 27 studies (1483 eyes) were pooled. By Reese–Ellsworth classification, globe salvage rates were 85% (95%CI:73–92%) for Group I, 78% (95%CI:70–85%) for Group II, 68% (95%CI:56–78%) for Group III, 47% (95%CI:34–60%) for Group IV, and 35% (95%CI:26–45%) for Group V (Va: 35% [95%CI:21–54%]; Vb: 42% [95%CI:29–56%]; those without sub-classification: 31% [95%CI:19–47%]). By International Classification, globe salvage rates were 93% (95%CI:80–97%) for Group A, 83% (95%CI:73–89%) for Group B, 73% (95%CI:54–86%) for Group C, 40% (95%CI:31–51%) for Group D, and 19% (95%CI:5–50%) for Group E. Standard carboplatin-etoposide-vincristine out-performed two-drug regimens (odds ratio (OR) = 1.9 (95%CI:1.3–3.0) for Groups I-IV and OR = 2.1 (95%CI:1.3–3.4) for Group V; p = 0.002 for each). For eyes with diffuse vitreous seeds (Vb), an enhanced regimen out-performed standard chemotherapy (OR = 2.4 [95%CI:1.3–4.7]; p = 0.004). In conclusion, two-drug regimens were less effective for all eyes, whereas enhanced regimens were more effective for eyes with vitreous seeds. Novel therapies can now be compared to these baseline globe salvage rates.

Conservative management of retinoblastoma: Challenging orthodoxy without compromising the state of metastatic grace. "Alive, with good vision and no comorbidity"

Retinoblastoma is lethal by metastasis if left untreated, so the primary goal of therapy is to preserve life, with ocular survival, visual preservation and quality of life as secondary aims. Historically, enucleation was the first successful therapeutic approach to decrease mortality, followed over 100 years ago by the first eye salvage attempts with radiotherapy. This led to the empiric delineation of a window for conservative management subject to a "state of metastatic grace" never to be violated. Over the last two decades, conservative management of retinoblastoma witnessed an impressive acceleration of improvements, culminating in two major paradigm shifts in therapeutic strategy. Firstly, the introduction of systemic chemotherapy and focal treatments in the late 1990s enabled radiotherapy to be progressively abandoned. Around 10 years later, the advent of chemotherapy in situ, with the capitalization of new routes of targeted drug delivery, namely intra-arterial, intravitreal and now intracameral injections, allowed significant increase in eye preservation rate, definitive eradication of radiotherapy and reduction of systemic chemotherapy. Here we intend to review the relevant knowledge susceptible to improve the conservative management of retinoblastoma in compliance with the "state of metastatic grace", with particular attention to (i) reviewing how new imaging modalities impact the frontiers of conservative management, (ii) dissecting retinoblastoma genesis, growth patterns, and intraocular routes of tumor propagation, (iii) assessing major therapeutic changes and trends, (iv) proposing a classification of relapsing retinoblastoma, (v) examining treatable/preventable disease-related or treatment-induced complications, and (vi) appraising new therapeutic targets and concepts, as well as liquid biopsy potentiality.

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.

Retinoblastoma treatment burden and economic cost: impact of age at diagnosis and selection of primary therapy

Purpose

To follow the treatment history of patients with retinoblastoma to identify the trends in the number of hospital visits over time and the direct cost of medical care as determined by age at diagnosis and selected primary treatment modality.

Design

An Institutional Review Board (IRB) approved consecutive retrospective case series.

Materials and methods

Records from the Bascom Palmer Eye Institute were reviewed to identify 115 eligible patients (176 eyes) with retinoblastoma who underwent treatment at the Ocular Oncology Service between 1995 and 2010 and were available for extended follow-up evaluation.

Results

Bilateral disease was present in 53% (N = 61) of all patients, and 79% (N = 90) of patients were diagnosed in the first six months of life. Chemotherapy was used to treat 75% (N = 86) of all patients and 95% (N = 36) of patients diagnosed in the first six months of life. 100% (N = 4) of patients presenting between the age of five and nine were enucleated. Per episode of care, the lowest-cost treatment strategy was enucleation, followed by focal laser therapy, systemic chemotherapy with planned enucleation, systemic chemotherapy, and lastly, intra-arterial melphalan chemotherapy.

Conclusion

Age at diagnosis is directly associated with the type of treatment chosen for retinoblastoma. The burden of retinoblastoma treatment on children and families is significant. The direct medical cost of intra-arterial chemotherapy per episode of care is comparable to systemic chemotherapy, but current strategies utilizing multiple planned episodes of intra-arterial chemotherapy are significantly more costly and may be associated with less systemic side effects and similar favorable outcomes. At the Bascom Palmer Eye Institute, intra-arterial chemotherapy has quickly become the treatment of choice for globe conserving therapy of retinoblastoma.

The treatment of retinoblastoma with four-drug regimen including cisplatin, etoposide, vincristine, and cyclophosphamide

Over an 11-year period, 59 patients (83 eyes) were treated with four-drug chemotherapy (cisplatin, etoposide, cyclophosphamide, and vincristine) at Hacettepe University, Departments of Ophthalmology and Pediatric Oncology. We evaluated the clinical features, treatment modalities, and outcome of these patients with a median follow-up of 55 months (range 9-130 months). Enucleation was performed as a first-line treatment for 30 eyes due to iris neovascularization and neovascular glaucoma, tumor in the anterior chamber regardless of the tumor stage, and for the patients with the Reese-Ellsworth (RE) group Vb. Chemotherapy was given regardless of tumor stages according to the RE groups in all 59 patients (83 eyes). Fifty-three eyes were treated with chemoreduction (CRD) and focal treatment. The rates of globe preservation were 87% for bilateral tumors and 35% for unilateral tumors in the CRD group. The 5-year overall (OS) and enucleation-free survival (EnFS) was 86.9% and 40%, respectively, for the whole group. At 3rd year, ocular survival rate for the eyes with vitreal or subretinal seeding was 58% and without seeding was 66% (P = .78). Seeding or subretinal collection may not indicate poor prognosis under intensive chemotherapy. The intensive four-drug chemotherapy protocol might have satisfactory results in the retinoblastoma (RBL) patients.

Compliance in retinoblastoma

OBJECTIVE

To evaluate disease is advanced, compliance in retinoblastoma.

METHODS

This is a retrospective descriptive study of patients of retinoblastoma registered at our cancer center from June 2003-February 2007 to study compliance.

RESULTS

Sociodemographic data of 177 patients revealed rural:urban ratio of 2:1, median age 36 months (unilateral disease) and 24 months (bilateral disease); median symptom duration 7.2 months. Overall, 84/141 evalued cases took adequate therapy; follow-up could be achieved in 67/141 (47.5%) cases in comparison to 92.4% in Hodgkin's lymphoma (p=0.001), 62.8% in acute myeloid leukemia (p=0.036) and 72.7% in non Hodgkin's lymphoma (p=0.001). There was no significant impact of any sociodemographic factors on compliance. Amongst those offered enucleation upfront for intraocular disease, it was accepted in 86/93 (92.5%) eyes.

CONCLUSION

This is one of the largest studies in relation to sociodemographic factors and clinical spectrum, and the only study from Asia evaluating compliance with recommended therapy in retinoblastoma. In order to improve ocular and patient salvage rates in Asian countries, exact causes for poor compliance in retinoblastoma need to be closely examined through a prospective study.

Analysis of ototoxicity in young children receiving carboplatin in the context of conservative management of unilateral or bilateral retinoblastoma

BACKGROUND

Carboplatin plays an important role in the conservative management of retinoblastoma, but is associated with risk of ototoxicity in these young children whose sensory prognosis may be also compromised by their loss of vision. This retrospective study analyzed the impact of carboplatin on hearing in the context of conservative management of children with retinoblastoma.

METHODS

Data for 175 children treated at the Institut Curie between 1994 and 2002 were analyzed.

RESULTS

Median age at diagnosis was 8 months (0-60). Carboplatin was administered on 3 days (200 mg/m(2)/day) or 5 days (160 mg/m(2)/day) with etoposide and with diode-laser therapy at the dose of 560 mg/m(2) (chemothermotherapy). Median cumulative dose of carboplatin was 2,880 mg/m(2) (560-6,160). Ototoxicity was investigated by pure-tone audiometry and scored by Brock's grading scale before and after treatment. The median follow-up of hearing assessment was 5 years (1.8-11). Ototoxicity was detected in 8 children: 3 grade 1, 1 grade 2, and 2 grade 4. The two patients with grade 4 hearing-loss required a hearing aid. Two children developed bilateral high frequency hearing-loss, considered to be secondary to carboplatin but with less than Brock grade 1. Ototoxicity was observed for a median cumulative dose of carboplatin of 3,120 mg/m(2) (1,200-5,830). Only one child developed ototoxicity during treatment. All other cases were discovered after the last dose of carboplatin with a median interval of 3.7 years (0-7.6). No other risk factor for ototoxicity was able to account for these lesions.

CONCLUSION

Children receiving carboplatin require long-term audiometric follow-up.

Published international classification of retinoblastoma (ICRB) definitions contain inconsistencies--an analysis of impact

PURPOSE

To determine the impact of subtle differences (most notably in their classification of group E eyes) in two published versions of the ICRB (Philadelphia and the Children's Hospital Los Angeles).

METHODS

Analysis of a series of 96 eyes with intra-ocular retinoblastoma.

RESULTS

The disparate criteria of the 2 published ICRB schemas affected group assignment of 5.2% of the eyes (25% of the group E eyes).

CONCLUSION

Discrepancies need to be reconciled to ensure accurate and uniform application of the ICRB.

Outcomes of a two-drug chemotherapy regimen for intraocular retinoblastoma

BACKGROUND

Retinoblastoma is the most common intraocular tumor of childhood. Vision salvage rates in advanced cases are less than ideal, and the optimal treatment for intraocular retinoblastoma has not been established. We report the results of an institutional retinoblastoma treatment trial to determine the vision salvage rates and toxicity of a regimen combining carboplatin and etoposide with focal retinal therapy.

PROCEDURE

Twenty-nine patients diagnosed with retinoblastoma in 48 eyes were treated between 1992 and 2004 with at least six cycles of carboplatin and etoposide combined with focal retinal therapy.

RESULTS

The response rate of eyes after six cycles of chemotherapy was 85.4%. Twenty-two eyes were enucleated, but only seven eyes received EBRT. The vision salvage rate without EBRT was 82.6% for eyes with Reese-Ellsworth (R-E) groups I-IV tumors and 20% for eyes with R-E group V tumors. The vision salvage rate without EBRT for eyes with Murphree groups A and B tumors was 77.3% but was only 26.9% for eyes with groups C and D tumors. Acute side effects were minimal.

CONCLUSIONS

The combination of carboplatin and etoposide with focal therapy is a well-tolerated regimen that has acceptable vision salvage rates for R-E groups I-IV and Murphree groups A and B retinoblastoma. This combination avoids the use of EBRT and the toxicity of additional chemotherapy agents. However, patients with R-E group V and Murphree groups C and D retinoblastoma have poorer outcomes and require more intensive therapy.

Current management strategies for intraocular retinoblastoma

Survival rates for retinoblastoma patients have increased dramatically over the last century, with documented 5-year survival figures reaching 87-99% in developed countries. During the last decade, there has been a dramatic paradigm shift in the treatment approach for intraocular retinoblastoma, emphasising chemoreduction protocols and minimising the use of external beam radiation. The recognition of the increased risk for second non-ocular cancers with external beam radiation contributed to the growing emergence of chemotherapy. Although chemoreduction protocols vary slightly between institutions, many centres are currently treating intraocular retinoblastoma with carboplatin, vincristine and etoposide as a three-drug regimen given in two to six cycles. Clinical studies have demonstrated that systemic chemotherapy must be combined with other modalities, such as laser treatment and cryotherapy, for adequate tumour control and many eyes with advanced intraocular disease require salvage therapy with radiation or enucleation. Therefore, modern centres treating retinoblastoma continue to manage patients with a variety of modalities, individualising the therapy according to the patient's presentation and clinical course.

Chemoreduction for intraocular retinoblastoma in Malaysia

In the last decade, chemotherapy in combination with focal therapy (chemoreduction) has been increasingly used in intraocular retinoblastoma to avoid enucleation and radiotherapy. The aim of this study was to assess the feasibility and outcome of chemoreduction in Malaysian children with retinoblastoma. This was a prospective study from August 2001 to January 2006. Twenty children (25 eyes) were given 4 cycles of chemoreduction, after which the response was assessed. Fourteen eyes showed a complete response, 10 eyes showed a partial response, and 1 eye had progressive disease. Twelve eyes developed progressive disease later, 9 after an initial complete response and 3 after a partial response. Overall, progressive disease occurred in 52%. There were 2 treatment failures, in Reese-Elsworth groups 3 and 4. Both eyes required enucleation. One eye in group 5 required second line chemotherapy to achieve a complete response. No eyes were irradiated. Five children (25%) defaulted follow-up, one of whom returned with disseminated disease. In conclusion, 4 cycles of chemoreduction achieved a durable complete response in only 12% of eyes. Chemoreduction is feasible in Malaysia but requires good patient compliance and close follow-up.

Treatment of retinoblastoma patients with chemoreduction plus local therapy: experience of the AC Camargo Hospital, Brazil

To evaluate the efficacy of conservative management of intraocular retinoblastoma with chemoreduction combined with local therapy with or without plaque radiation in the preservation of the eye, and avoidance of external beam radiation therapy (EBRT) (success rate). From 1995 to 2000, 84 newly diagnosed patients with intraocular retinoblastoma were admitted to the Pediatric Department of the Hospital do Cancer A.C. Camargo, São Paulo, Brazil. All children were treated with 2 to 6 cycles of chemotherapy (carboplatin, vincristine, and etoposide) plus local therapy (cryotherapy, laser photocoagulation, and thermotherapy), or plaque radiation therapy during and/or after the chemotherapy. The Mann-Whitney test was used to compare means of quantitative variables. The chi test or the Fisher exact test were employed to verify the association between the outcome and the independent variables. For all tests alpha=5% was adopted. Success rate was higher for patients with bilateral tumors (54%) than for children with unilateral tumors (19%) (P=0.003). For patients with Reese-Ellsworth stages I, II, and III, no statistically significant differences in the success rates were noted in the group of unilateral (50%) and bilateral tumors (79.1%) (P=0.179). Among children with Reese-Ellsworth stages IV and V, the success rate was significantly higher for patients with bilateral tumors (40.7%) than for those with unilateral (0%) (P=0.012). Chemoreduction combined with local therapy, with or without plaque radiotherapy, is efficacious in avoiding enucleation and the use of external beam radiation therapy for children with intraocular retinoblastoma.