Multiagent chemotherapy as neoadjuvant treatment for multifocal intraocular retinoblastoma

Clinical characteristics, treatment and prognosis of infants with retinoblastoma: a multicenter, 10-year retrospective analysis

BACKGROUND

To summarize the characteristics and treatment, and analyze the prognosis of large number of infants with retinoblastoma (RB) in China through a multicenter, 10-year retrospective analysis.

METHODS

The data of RB infants were collected from multiple centers. The characteristics and survival prognosis were analyzed. The overall survival (OS) rate was estimated by the Kaplan-Meier method. Multivariate Cox survival analysis was to evaluate the independent risk factors affecting the prognosis of RB infants.

RESULTS

A total of 373 RB infants (202 boys and 171 girls) were included, the median age was 6.22 months (10 days to 11.93 months). The median follow-up time of RB infants was 18.4 (1.02-122.81 months). After excluding the lost to follow-up cases, the OS rate was 97.7% (345/353). Kaplan-Meier survival analysis indicated that 9 cases died and the median survival time was not reached. Univariate analysis of prognostic factors revealed eye affected, presenting signs, left eye stage and recurrence to be poor prognostic factors for OS rate in RB infants (all P < 0.05). Multivariate Cox regression analyses for OS showed recurrence (HR = 1.376, 95% CI: 0.878-2.156, P = 0.048) was an independent factor for prognosis of infants with RB. The median survival time of infants underwent chemotherapy + intra-arterial chemotherapy (IAC) + enucleation + vitrectomy was the longest than other treatments (n = 9, 47.64 months, OS = 100%, all P < 0.05). There was a history of RB in 17 infants' lineal relatives. Kaplan-merier survival analysis indicated 1 case died and the median survival time was not reached.

CONCLUSION

Recurrence is an independent factor for prognosis of RB infants, which still needs attention after treatment. Early screening, comprehensive treatments and follow-up of patients may lead to improvements of prognosis of RB infants.

Comparing efficacy and side effects of two systemic chemotherapy regimens for eye-preserving therapy in children with retinoblastoma

BACKGROUND

Eye-preserving therapy in retinoblastoma comprises systemic chemotherapy, but studies analyzing the efficacy of different chemotherapy regimens are scarce.

METHODS

The efficacy and side effects of two different eye-preserving chemotherapy regimens containing either vincristine, etoposide, and carboplatin (VEC) or cyclophosphamide, vincristine, etoposide, and carboplatin (CyVEC) were compared in a prospective non-interventional observational study including children diagnosed with retinoblastoma between 2013 and 2019 in Germany and Austria. Event-free eye survival (EFES) and overall eye survival (OES) of all 164 eyes treated with both regimens and risk factors were investigated.

RESULTS

The EFES after VEC (2-year EFES 72.3%) was higher than after CyVEC (2-year EFES 50.4%) (p_logrank  < .001). The OES did not differ significantly between the two treatment groups (p_logrank  = .77; 2-year OES VEC: 82.1% vs. CyVEC: 84.8%). Advanced International Classification of Retinoblastoma (ICRB) group was prognostic for a lower EFES (p_logrank  < .0001; 2-year EFES ICRB A/B/C 71.3% vs. ICRB D/E 43.0%) and OES (p_logrank  < .0001; 2-year OES ICRB A/B/C 93.1% vs. ICRB D/E 61.5%). The multivariate analysis showed that age at diagnosis older than 12 months and ICRB A/B/C were associated with better EFES. No second malignancies or ototoxicities were reported after a follow-up of median 3.1 years after diagnosis of retinoblastoma (range 0.1-6.9 years).

CONCLUSIONS

Despite omitting cyclophosphamide, the EFES was higher after VEC chemotherapy that contains higher doses of carboplatin compared to CyVEC. The major risk factor for enucleation was advanced ICRB tumor grouping. Randomized clinical trials on efficacy and side effects of eye-preserving chemotherapy are required to tailor treatment protocols for retinoblastoma patients.

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.

Adjuvant use of laser in eyes with macular retinoblastoma treated with primary intravenous chemotherapy

BACKGROUND

Adjuvant use of laser with systemic chemotherapy for treatment of retinoblastoma may reduce recurrence rates while also causing local side effects. Information is lacking on the effect of laser on visual outcomes.

METHODS

A retrospective review of two retinoblastoma centres in the United Kingdom was conducted. Patients were included if there was a macular tumour in at least one eye. Eyes that received chemotherapy alone were compared with eyes that received chemotherapy plus adjuvant laser.

RESULTS

A total of 76 patients and 91 eyes were included in the study. Systemic chemotherapy alone was used in 71 eyes while chemotherapy plus laser was used in 20 eyes. Demographic characteristics of both groups were similar. Macular relapse rates were similar between groups: 22/71 (31%) eyes in chemotherapy group and 9/20 (45%) eyes in laser group (p=0.29). There was no increase in vitreous relapses in the laser group (2/20 eyes), compared with the chemotherapy group 10/71 eyes (p=0.99). Survival analysis demonstrated similar time to first relapse between groups. Final visual acuity was equal between groups with 6/15 or better present in 31.1% of eyes in the chemotherapy group and 37.5% of eyes in the laser group (p=0.76). Presence of tumour at the fovea was predictive of final visual acuity, regardless of treatment group.

CONCLUSION

Adjuvant laser in the treatment of retinoblastoma is safe and does not lead to increased rate of vitreous recurrence. Final visual acuity is determined by the presence of tumour at the fovea and not the use of laser.

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.

Analysis of the short-term curative effect of 356 cases of intraocular retinoblastoma in children

IMPORTANCE

Retinoblastoma (Rb) is the most common primary malignant intraocular cancer in children. Systemic chemotherapy combined with local therapy is safe and effective for intraocular Rb.

OBJECTIVE

To summarize the short-term outcomes of patients with Rb to provide evidence for optimizing treatment protocols and improving therapeutic safety and efficacy.

METHODS

The clinical data of 356 patients (486 eyes) with intraocular Rb admitted to our center from December 2009 to April 2017 were retrospectively analyzed. The measures included drug toxicity, eye-preservation rate, and survival rate, with an emphasis on safety and short-term efficacy. The date of last follow-up was 30 November, 2017.

RESULTS

The patients comprised 226 unilateral Rb and 130 bilateral Rb. Enucleation before chemotherapy was performed in 72 patients. Among the 174 patients with unilateral Rb, enucleation after chemotherapy was performed in 80 patients (46.0%), and the eye was not enucleated in 89 (51.1%); 68 eyes were preserved (68/114, 59.6%) in Group D and 20 eyes (20/59, 33.8%) in Group E. Among the 220 eyes in patients with bilateral Rb, enucleation after chemotherapy was performed for 35 eyes; the eye-preservation rate was 91.7% in Group C, 79.1% in Group D, and 52.1% in Group E. All patients developed grade II to IV myelosuppression after chemotherapy, among whom 18 patients (5%) requiring transfusion. Fourteen patients (3.9%) died of intracranial metastasis following self-elected discontinuation of treatment (n = 7). Patients were followed up for a median of 47 (range, 1-96) months. The expected 5-year overall survival rate was 95.3% (96.7% for unilateral Rb and 92.9% for bilateral Rb, P = 0.074).

INTERPRETATION

The VEC (vincristine, etoposide, and carboplatin) regimen with local treatment was safe for intraocular Rb. Intracranial metastasis remains the most common cause of Rb-related death.

Prior non-irradiative focal therapies do not compromise the efficacy of delayed episcleral plaque brachytherapy in retinoblastoma

BACKGROUND/AIMS

Non-irradiative local therapies have shown promise in delaying or supplanting external beam radiotherapy (EBRT) and enucleation in patients with retinoblastoma. We hypothesised that prior focal therapy does not compromise the efficacy of delayed episcleral plaque brachytherapy (epBRT).

METHODS

We performed an institutional review board-approved medical record review of patients with retinoblastoma who were treated with I-125 epBRT prior to (primary) or following chemoreduction (delayed), alone and in combination with non-irradiative focal therapy. Clinical and treatment characteristics were retrieved. Treatment failure was defined as the need for subsequent EBRT and/or enucleation. Event-free and ocular survival rates were calculated from the date of plaque placement. The cumulative incidences (CIs) of treatment failure and enucleation were compared across strata using Gray's test.

RESULTS

We identified 50 patients with retinoblastoma (54 eyes), who received a total of 56 plaques between January 1986 and December 2010, with a median follow-up of 8.3 years (range, 0.8-21.2 years). The median time from diagnosis to plaque placement was 12.7 months (range, 0.1-128 months). The CI and 95% CI of treatment failure and enucleation following epBRT at 5 years was 37%±7.2% and42.2%±7.3%, respectively. The lack of prior diode or green laser therapy was predictive of increased risk for treatment failure (p=0.02 and 0.03). International Classification group C or D was predictive of decreased time to enucleation (p=0.004). The use of any focal therapy was not predictive of time to treatment failure (p=0.33).

CONCLUSIONS

The use of non-irradiative focal therapies prior to or following epBRT does not decrease the time to enucleation or treatment failure.

Systemic neoadjuvant chemotherapy for Group B intraocular retinoblastoma (ARET0331): A report from the Children's Oncology Group

PURPOSE

To evaluate a chemoreduction regimen using systemic vincristine and carboplatin (VC) and local ophthalmic therapies to avoid external-beam radiotherapy (EBRT) or enucleation in patients with Group B intraocular retinoblastoma.

PATIENTS AND METHODS

Twenty-one patients (25 eyes) were treated with six cycles of VC, accompanied by local ophthalmic therapies after cycle 1. The primary study objective was to determine the 2-year event-free survival (EFS) where an event was defined as the use of systemic chemotherapy in addition to vincristine or carboplatin, EBRT, and/or enucleation.

RESULTS

All patients had tumor regression after the first cycle of VC and only two patients had progression during therapy. There were seven treatment failures within 2 years of study enrollment, resulting in 2-year EFS of 65% and early study closure in accordance with the statistical design. The 2-year cumulative incidence of enucleation was 15%; for external beam radiation therapy, it was 10%; and for chemotherapy to control progressive disease, it was 10%. All patients sustaining a treatment failure were salvaged with additional therapy.

CONCLUSIONS

For the majority of patients with Group B intraocular retinoblastoma, chemoreduction with VC, without etoposide, in conjunction with local therapy provides excellent opportunity for ocular salvage. Local therapy given with every chemotherapy cycle and incorporation of etoposide may provide improved ocular salvage rates. Central review of group at diagnosis is critical in assigning appropriate therapies.

Focal laser treatment in addition to chemotherapy for retinoblastoma

BACKGROUND

Retinoblastoma is the most common primary intraocular malignancy of childhood. Systemic chemotherapy is a common treatment for intraocular retinoblastoma, and laser treatment is used as adjuvant therapy during or immediately after chemotherapy courses in selected cases.

OBJECTIVES

To compare the effectiveness and safety of adding focal laser therapy to systemically-delivered chemotherapy in treating intraocular retinoblastoma.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 9), MEDLINE Ovid (1946 to 20 October 2016), Embase Ovid (1980 to 20 October 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 20 October 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch); searched 20 October 2016, ClinicalTrials.gov (www.clinicaltrials.gov); searched 20 October 2016, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 20 October 2016. We did not use any date or language restrictions in the electronic searches for trials.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) of systemic chemotherapy with versus without adjuvant laser therapy for postequatorial retinoblastoma.

DATA COLLECTION AND ANALYSIS

We planned to use standard methodological procedures expected by Cochrane. We planned to meta-analyse the primary outcome, that is the proportion of eyes with recurrence of tumours within three years from treatment MAIN RESULTS: No studies met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

No evidence from randomised controlled trials was found to support or refute laser therapy in addition to systemic chemotherapy for postequatorial retinoblastoma.

Conservative treatment of retinoblastoma: a prospective phase II randomized trial of neoadjuvant chemotherapy followed by local treatments and chemothermotherapy

PurposeIntraocular retinoblastoma treatments often combine chemotherapy and focal treatments. A first prospective protocol of conservative treatments in our institution showed the efficacy of the use of two courses of chemoreduction with etoposide and carboplatin, followed by chemothermotherapy using carboplatin as a single agent and diode laser. In order to decrease the possible long-term toxicity of chemotherapy due to etoposide, a randomized neoadjuvant phase II protocol was conducted using vincristine-carboplatin vs etoposide-carboplatin.Patients and methodsThe study was proposed when initial tumor characteristics did not allow front-line local treatments. Patients included in this phase II noncomparative randomized study of neoadjuvant chemotherapy received vincristin-carboplatin (new arm) vs etoposide-carboplatin (our reference arm). They were subsequently treated by local treatments and chemothermotherapy. Primary end point was the need for secondary enucleation or external beam radiotherapy (EBRT) not exceeding 40% at 2 years.ResultsA total of 65 eyes in 55 children were included in the study (May 2004 to August 2009). Of these, 32 eyes (27 children) were treated in the arm etoposide-carboplatin and 33 eyes (28 children) in the arm vincristin-carboplatin. At 2 years after treatment, 23/33 (69.7%) eyes were treated and salvaged without EBRT or enucleation in the arm vincristin-carboplatin and 26/32 (81.2%) in the arm etoposide-carboplatin.ConclusionEven if the two treatment arms could be considered as sufficiently active according to the study decision rules, neoadjuvant chemotherapy by two cycles of vincristine-carboplatin followed by chemothermotherapy appear to offer less optimal local control than the etoposide-carboplatin combination.

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.

Successful treatment of macular retinoblastoma with superselective ophthalmic artery infusion of melphalan

PURPOSE

To report our experience with superselective ophthalmic artery infusion of melphalan (SOAIM) for macular retinoblastoma to obtain tumor control while preserving as much useful vision as possible.

METHODS

Five patients with newly diagnosed unilateral retinoblastoma involving the macula were selected within a group of patients eligible for SOAIM as the primary treatment.

RESULTS

The mean tumor basal dimension and thickness in this group of five patients with macular retinoblastoma were 11.6 and 12.3 mm, respectively. The stage at diagnosis ranged from II to VB (Reese-Ellsworth) or B to D (International Classification System). Tumor regression with SOAIM was achieved in all cases with regression patterns type I in four cases and III in one case.

CONCLUSIONS

SOAIM can be of value in the treatment of macular retinoblastoma. It may allow the salvage of the residual eyesight with a low rate of complications due to the local and systemic toxicity related to chemotherapy.

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.

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.

Carboplatin +/- topotecan ophthalmic artery chemosurgery for intraocular retinoblastoma

Purpose

Carboplatin administered systemically or periocularly can result in dramatic and prompt regression of retinoblastoma. However, both routes are rarely curative alone and have undesirable side effects. We aimed to assess the efficacy and toxicity of carboplatin +/− topotecan delivered by ophthalmic artery chemosurgery whereby chemotherapy is infused into the eye via the ophthalmic artery.

Methods

This retrospective, IRB-approved study investigated retinoblastoma patients whom received carboplatin +/− topotecan ophthalmic artery chemosurgery. Patient survival, ocular survival, hematologic toxicity, ocular toxicity, second cancer development and electroretinogram response were all evaluated.

Results

57 carboplatin +/− topotecan infusions (of 111 total) were performed in 31 eyes of 24 patients. The remaining infusions were melphalan-containing. All patients were alive and no patient developed a second malignancy at a median follow up of 25 months. The Kaplan-Meier estimate of ocular survival at two years was 89.9% (95% confidence interval [CI], 82.1–97.9%) for all eyes. Grade 3 or 4 neutropenia developed in two patients and one patient developed metastatic disease. By univariate analysis, neither increasing maximum carboplatin/topotecan dose nor cumulative carboplatin/topotecan dose was associated with statistically significant reduction in the electroretinogram responses.

Conclusion

Carboplatin +/− topotecan infusions are effective for ophthalmic artery chemosurgery in retinoblastoma: they demonstrate low hematologic and ocular toxicity and no statistically significant influence on electroretinogram responses, and used in conjunction with melphalan-containing OAC, demonstrate excellent patient survival and satisfactory ocular survival.

Current therapy and recent advances in the management of retinoblastoma

Retinoblastoma is the most common intraocular malignancy in children. The survival of retinoblastoma patients and visual outcome has improved dramatically in the developed world. This can be attributed to early tumor recognition and advances in the management of retinoblastoma. Chemoreduction followed by adjuvant consolidative treatment has replaced external beam radiotherapy as the primary modality of treatment for intraocular retinoblastoma. Further, histopathological high-risk factors have been identified in enucleated eyes, allowing use of prophylactic chemotherapy to take care of possible micrometastasis. The survival in case of extraocular retinoblastoma is still low, and the reported survival rate ranges between 50% and 70%. In developing countries, the overall survival of retinoblastoma patients remains low, primarily due to a delayed presentation, resulting in larger proportions of extraocular disease compared with the developed world, where majority of the disease is intraocular. Greater efforts need to be directed toward early tumor recognition in order to improve the survival of retinoblastoma patients in the developing world. In this article, we provide an overview of the current clinical management of retinoblastoma.

The clinical outcomes of proton beam radiation therapy for retinoblastomas that were resistant to chemotherapy and focal treatment

Purpose

To evaluate the clinical results of proton beam radiation therapy (PBRT) for treatment of retinoblastoma.

Methods

Children with retinoblastoma who were treated with chemotherapy and focal treatment such as brachytherapy and thermotherapy but showed no response or developed recurrences later received PBRT. The PBRT strategy was designed to concentrate the radiation energy to the retinoblastoma and spare the surrounding healthy tissue or organs.

Results

There were three patients who received PBRT. The first patient received PBRT because of an initial lack of tumor regression with chemotherapy and brachytherapy. This patient showed regression after PBRT. The second patient who developed recurrence of retinoblastoma as diffuse infiltrating subretinal seeding was taken PBRT. After complete regression, there was recurrence of tumor and the eye was enucleated. The third patient had unilateral extensively advanced retinoblastoma. Initial chemotherapy failed and tumor recurred. The tumor responded to PBRT and regressed significantly. However, the eye developed sudden multiple recurrences, so we had to perform enucleation.

Conclusions

PBRT for retinoblastoma was effective in cases of showing no response to other treatment modalities. However, it should be carefully applied when there was recurrence of diffuse infiltrating subretinal seeding or extensively advanced retinoblastoma initially.

Molecular pathology of retinoblastoma

Retinoblastoma (RB) is an embryonic neoplasm of retinal origin. For many years, scientists have sought the fundamental origins of tumorigenesis, with the ultimate hope of discovering a cure. Indeed, these efforts have led to a significant understanding that multiple molecular and genetic aberrations, such as uncontrolled proliferation and the inhibition of apoptosis that contribute to the canonical characteristics of tumor biology. Despite these advances, a thorough understanding, such as the precise cells, which are the targets of neoplastic transformation, especially in solid tumors, is currently lacking. The focus of this review is to emphasize the molecular defects involved in the RB tumor progression and mechanisms associated with inhibition of tumor cell apoptotic processes. This review also discusses the importance of target molecules characterization and their potential therapeutic or prognostic use in RB disease.

Rabbit model of retinoblastoma

We created a rabbit model of retinoblastoma and confirmed the tumor clinically and histopathologically. Seventeen New Zealand rabbits were immunosuppressed with cyclosporin A at doses of 10–15 mg/kg. At day 3, the animals received a 30 μl subretinal injection of 1 × 10⁶ cultured WERI retinoblastoma cells. Digital fundus images were captured before euthanasia, and the eyes were submitted for histopathology. Retinoblastoma cells grew in all the inoculated eyes and established a tumor under the retina and/or in the vitreous. New blood vessels in the tumor were observed starting at week 5. Cuffs of viable tumor cells surrounded the blood vessels with regions of necrosis present at 70–80 μm from nutrient vessels. Occasional tumor seeds in the vitreous histologically exhibited central necrosis. This rabbit model demonstrated similar fundus appearance and pathologic features to human retinoblastoma and may be used as a model to test various routes of drug delivery for retinoblastoma.

Expression of the multi-drug resistance proteins and the pregnane X receptor in treated and untreated retinoblastoma

PURPOSE

To compare the expression of pregnane xenobiotic receptor and certain multi-drug resistance proteins in retinoblastoma.

METHODS

Using tissue microarray analyses, we studied 62 pathology specimens for expression of pregnane xenobiotic receptor, multi-drug resistance 1/P glycoprotein, multi-drug resistance proteins 1, 2, and 4, and breast cancer resistant protein.

RESULTS

Comparing tumors treated with primary enucleation with tumors treated with chemotherapy and/or radiation showed no significant differences in the expression of multi-drug resistance proteins or pregnane xenobiotic receptor. Pregnane xenobiotic receptor was correlated with multi-drug resistance protein 2 expression (p < 0.001).

CONCLUSION

Our results indicate selection, rather than induction, of chemoresistant cells as a cause for treatment failure in managing retinoblastoma with primary systemic chemotherapy.

Retinoblastoma: a three-year-study at a Brazilian medical school hospital

OBJECTIVE

To present the characteristics and treatment outcomes of patients with retinoblastoma.

METHODS

A retrospective case series was conducted to review the records of all new patients diagnosed with retinoblastoma between 2003 and 2005. Eyes with early disease, or advanced disease with potential vision were treated with chemotherapy (carboplatin and etoposide) in conjunction with early local therapy (laser or cryo). Radiotherapy was used in cases where the disease did not respond to the above protocols or in recurrent cases. Eyes in the late stage of disease with no potential vision in the initial examination or eyes and where conservative treatment had failed were enucleated.

RESULTS

In total, we reviewed 28 new cases of retinoblastoma, 15 of which were unilateral and 13 of which were bilateral (46%). These data correspond to a mean of 9.3 new cases per year (0.77 case/ month). The mean age at diagnosis was 33.8 months for unilateral cases, and 19.15 months for bilateral cases (p=0.015). Leucocoria was the major presenting symptom (75%). All but one patient with unilateral disease had the affected eye enucleated due to advanced disease (mean follow-up: 39.91 months). Among the 13 bilateral cases, 13 eyes (50%) were enucleated, 11 eyes (42.4%) were saved with chemotherapy in conjunction with local therapy and 2 eyes (7.6%) were saved using external beam radiotherapy (mean follow-up: 41.91 months). In unilateral and bilateral disease, pathology data revealed choroid involvement in 50% and 30%, respectively, and optic nerve invasion in 92% and 50%, respectively.

CONCLUSION

In this population, retinoblastoma was diagnosed too late and most eyes were consequently enucleated. In cases with bilateral disease, half of the eyes were preserved.

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.

Conservative treatments of intraocular retinoblastoma

OBJECTIVE

To describe the efficacy of conservative management of retinoblastoma by an association of conservative ocular therapies and chemothermotherapy.

DESIGN

Phase II prospective nonrandomized trial.

PARTICIPANTS

Eighty-three children were included (115 eyes).

METHODS

Conservative ocular therapies and chemothermotherapy (intravenous carboplatin followed by transpupillary thermotherapy to the tumor) after chemoreduction by 2 cycles of carboplatin and etoposide.

MAIN OUTCOME MEASURES

Use of external beam therapy and ocular tumor control.

RESULTS

One hundred fifteen of the 147 affected eyes were eligible for conservative management. Nineteen children had unilateral lesions (22.8%), and 64 (77.1%) had bilateral lesions. Sixty-six children received neoadjuvant chemotherapy before ocular therapy, which consisted of one or a combination of several techniques: chemothermotherapy (65 children [86 eyes]) with a mean of 3 cycles per child, thermotherapy alone (22 children [24 eyes]), cryoapplication (49 children [58 eyes]), and iodine 125 brachytherapy (26 children [29 eyes]). Tumor control was achieved for 97 eyes (84%). At the end of the study, external beam radiotherapy (EBR) was necessary for a total of 9 children (11%) and 13 eyes (12%). Enucleation was necessary for a total of 23 eyes (20%), because of complications in 5 cases.

CONCLUSIONS

Neoadjuvant chemotherapy with 2 cycles of carboplatin and etoposide followed by ocular therapy and chemothermotherapy achieves satisfactory tumor control and permits a low need for EBR.

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.

Incidence of New Tumor Formation in Patients with Hereditary Retinoblastoma Treated with Primary Systemic Chemotherapy: Is There a Preventive Effect?

PURPOSE

To report the incidence of new tumor formation in hereditary retinoblastoma patients treated with primary systemic chemotherapy.

DESIGN

Noncomparative retrospective case series.

PARTICIPANTS

Fifty-eight consecutive patients with hereditary retinoblastoma treated with primary systemic chemotherapy.

METHODS

The charts of 58 consecutive patients with hereditary retinoblastoma treated between January 1996 and August 2005 were reviewed. Data extracted included gender, age at diagnosis, family history of retinoblastoma, laterality of disease, tumors per eye, Reese-Ellsworth grouping of affected eyes, starting and ending dates for chemotherapy, number of cycles of chemotherapy, chemotherapy regimen, need for external beam radiotherapy and/or enucleation, and development and location (macula, midzone, and periphery) of new tumors after the start of systemic chemotherapy.

MAIN OUTCOME MEASURE

New tumor formation after treatment with primary systemic chemotherapy.

RESULTS

Of the 58 patients, 48 had bilateral involvement at diagnosis. Median age at diagnosis was 6.6 months. Thirteen patients had a positive family history. Of the eyes with tumor (n = 106) at diagnosis, 52 (49%) were in Reese-Ellsworth groups I to III, whereas 54 (51%) were in group IV or V. Seven patients (12%) with a median age of 1.6 months at diagnosis formed 36 new tumors in 11 eyes after the start of chemotherapy. Median time from initiation of chemotherapy to detection of the first new tumor was 3 months (range, 1-15). Cumulative incidence of new tumor formation at 2 years was 10+/-3%. An age of <6 months at diagnosis, family history of retinoblastoma, and Reese-Ellsworth grouping of I to III were found to correlate significantly with an increased incidence of new tumor formation (P<0.001, P<0.001, and P = 0.021, respectively). Median follow-up for all patients was 5 years (range, 1-10.1).

CONCLUSION

New tumors continue to form in patients with hereditary retinoblastoma despite treatment with primary systemic chemotherapy. Younger patients and those with a positive family history are more likely to have new tumors formed. However, chemotherapy may impact small previously undetected lesions by slowing their growth and facilitating later focal consolidation.

A phase II trial of carboplatin for intraocular retinoblastoma

BACKGROUND

Retinoblastoma patients with RB1 germline mutations are at risk of developing second malignancies and external beam radiation therapy increases the risk. Carboplatin-containing chemotherapy regimens in conjunction with local therapies have been investigated for intraocular retinoblastoma, but the lack of data regarding the efficacy of single agent intravenous carboplatin prompted this phase II study.

PROCEDURE

Twenty-five patients (43 eyes) were treated with intravenous carboplatin (18.7 mg/kg for patients < 12 kg, 560 mg/m(2) for patients >/= 12 kg). Patients received a median of two cycles of carboplatin (range one to five cycles) beginning at a median age of 5 months (range 14 days to 22 months).

RESULTS

All patients were extraocular disease free during the follow-up period (median 76.3 months). Responses were noted in 33 of 36 evaluable eyes (92%). The 5-year overall ocular and ocular event-free survivals were 93.3% (95% CI, 84.4-100%) and 43.5% (95% CI, 25.8-61.3%) for eyes treated for Reese-Ellsworth (RE) group 1-3 disease and 25.0% (95% CI, 1.0-50.0%) and 8.3% (95% CI, 0-24.0%) for RE group 4-5 disease, respectively. No non-hematopoietic serious or permanent toxicities related to the chemotherapy were observed.

CONCLUSION

When used as a neoadjuvant agent, carboplatin usually leads to objective responses of intraocular retinoblastoma. The 5-year ocular event-free survival appears inferior to other protocols using more extensive chemotherapy, but with greater radiation therapy usage, overall ocular survival rate for RE group 1-3 eyes was excellent.

Diagnosis and management of retinoblastoma

BACKGROUND

Retinoblastoma is a highly malignant tumor of the eye that manifests most often in the first 3 years of life.

METHODS

Published articles were reviewed to evaluate the clinical features and current methods of diagnosis and to assess the trends in management.

RESULTS

This malignancy leads to metastatic disease and death in 50% of children worldwide but in less than 5% of children in the United States and other developed nations with advanced medical care. Over the past decade, there has been a trend away from enucleation and external beam radiotherapy and toward chemoreduction followed by focal therapies. This is largely due to more effective chemotherapeutic regimens, improved focal treatment modalities, and the desire to avoid loss of the globe and/or exposure to radiotherapy. Chemoreduction and focal therapies are most successful for eyes with minimal to moderate retinoblastoma, with enucleation needed in less than 15% of cases. Eyes with very advanced retinoblastoma require enucleation in approximately 50% of cases.

CONCLUSIONS

Progress in the clinical recognition and management of retinoblastoma has led to high survival rates. Improved methods of treatment using chemoreduction and focal treatments without the need for external beam radiotherapy allow preservation of the eye in some cases, often with visual function.

Macular Retinoblastoma: Evaluation of Tumor Control, Local Complications, and Visual Outcomes for Eyes Treated with Chemotherapy and Repetitive Foveal Laser Ablation

OBJECTIVE

To determine tumor control rates, complication rates, and visual acuity (VA) for patients with macular retinoblastoma undergoing systemic chemotherapy and foveal diode laser ablation.

DESIGN

Noncomparative retrospective case series.

PARTICIPANTS

All patients with retinoblastoma in the macula at the Bascom Palmer Eye Institute between 1991 and 2004 were evaluated. Patients included in the study were managed by the same clinician with a planned therapeutic strategy.

METHODS

Patients with Reese-Ellsworth groups I to IV disease underwent 4 to 9 cycles of systemic chemotherapy with vincristine, etoposide, and carboplatin, and patients with group V disease underwent 6 to 10 cycles with or without cyclosporine. All tumors underwent repetitive diode laser ablation (2-24 sessions) applied to the foveal and extrafoveal portions of tumors at each visit until tumors were deemed inactive for at least 6 months.

MAIN OUTCOME MEASURES

Recurrence requiring external beam radiation therapy or enucleation; VA; and complications including iris atrophy, peripheral focal lens opacity, peripheral anterior synechiae, and foveal neovascular membrane.

RESULTS

Forty-four eyes of 33 patients were treated. Eyes were classified as Reese-Ellsworth group I (1 [2%]), II (6 [12%]), III (3 [7%]), IV (5 [9%]), or V (29 [67%]). Thirty-eight eyes (86%) had successful tumor control and avoided enucleation at a median follow-up of 36 months. At 3 years, tumor control rates were 100% for Reese-Ellsworth groups I to IV and 83% for group V. All eyes requiring enucleation were in Reese-Ellsworth group V. No eyes required external beam radiation. The most common complications were iris atrophy (61%) and focal lens opacity (14%). Strabismus was noted in 16% of eyes. Snellen VA measured 20/40 or better in 36% of eyes, 20/80 or better in 57%, and 20/400 or better in 86%. An increasing number of laser applications and chemotherapy cycles was not associated with decreased VA, strabismus, or development of an afferent pupillary defect but was associated with development of local complications.

CONCLUSIONS

A unique approach to the application of diode laser therapy characterized by repetitive foveal treatments and aggressive chemotherapy resulted in tumor control rates that exceed those previously published. Furthermore, despite laser application directly to the fovea, 57% of patients retained 20/80 or better vision.

Focal Stereotactic External Beam Radiotherapy as a Vision-sparing Method for the Treatment of Peripapillary and Perimacular Retinoblastoma: Preliminary Results

AIMS

Chemotherapy with aggressive focal ablative therapy is now the mainstay of retinoblastoma therapy. Our experience presents an evolution from conventional radiotherapy by treating posterior pole tumours with focal stereotactic fractionated radiotherapy (SRT).

MATERIALS AND METHODS

A retrospective chart review was conducted of five patients (six eyes) treated with SRT at the Hospital for Sick Children and Princess Margaret Hospital, Toronto, Canada, between 1999 and 2004. The prescribed dose was 40 Gy delivered in 20 fractions once daily using 6 MV photons.

RESULTS

Five patients (six eyes) were treated. The median age at the time of SRT was 18 months. The median follow-up was 46.5 months as of September 2004. Four patients were treated for a posterior pole focal tumour by focal SRT, and one patient was treated for vitreous seeding with whole-eye SRT. In patients treated with focal SRT, the median doses to the tumour, optic chiasm and brainstem were 41.92, 0.25 and 0.07 Gy, respectively, and to the ipsilateral optic nerve, globe and lens were 9.98, 19.11 and 3.74 Gy, respectively. The median doses to the ipsilateral and contralateral orbital bone were 6.73 Gy (range 5.99-8.29 Gy) and 2.31 Gy (range 0.88-7.08 Gy), respectively. A complete response (residual inactive scar tissue) was seen in four of the five focal tumours treated, with one tumour responding with a partial response (suspicious residual scar tissue). No acute or late side-effects occurred in patients treated with focal SRT. Only the patient treated with whole-eye SRT developed late effects of cataract and corneal ulceration. One patient suffered recurrence within the radiation field 5 months after focal SRT. Control of this recurrence was successful using chemotherapy and focal therapy. No eye has been enucleated.

CONCLUSION

Vision-sparing focal SRT for localised tumour masses in critical locations can control tumours with minimal side-effects and a minimal dose to the surrounding critical normal tissue.

Socioeconomic impact of modern multidisciplinary management of retinoblastoma

OBJECTIVE

Our objective for this study was to examine the impact of the modern management of intraocular retinoblastoma on the patient and the family.

METHODS

This study comprises a retrospective, noncomparative case series of 25 consecutive patients with multifocal, intraocular retinoblastoma that was treated with primary systemic chemotherapy. Medical charts were reviewed, and the following data were extracted: patients' age and gender, laterality of disease, and Reese-Ellsworth classification of each eye as well as the number of central venous lines placed, cycles of chemotherapy received, outpatient appointments, examinations under anesthesia, focal therapies administered, computed tomography/MRI, radiation treatments, anesthetic procedures administered, and miles traveled.

RESULTS

Twenty patients with bilateral and 5 with unilateral intraocular retinoblastoma (median age: 9.3 months) had 895 outpatient appointments and underwent 698 examinations under anesthesia with 230 focal therapies, 347 days of radiotherapy, 226 computed tomography scans/MRIs, and 38 central venous line placements. A total of 1272 anesthetic procedures (median: 50) were performed with no major complication. In all, patients traveled 822312 miles (median: 22214 miles) to receive their care. The median follow-up was 82 months.

CONCLUSIONS

Successful retinoblastoma management requires close surveillance, aggressive consolidation, and numerous anesthetic procedures, all of which the patients and the families must endure. There is a significant impact on the patient, the family, and hospital resources.

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.

Effect on ocular survival of adding early intensive focal treatments to a two-drug chemotherapy regimen in patients with retinoblastoma

PURPOSE

To evaluate vincristine and carboplatin with intensive focal treatments in the management of intraocular retinoblastoma.

DESIGN

Noncomparative, retrospective interventional case series.

METHODS

SETTING

Institutional.

PATIENT POPULATION

Sixteen patients (11 bilateral, 5 unilateral) with intraocular retinoblastoma. Interventional procedures: Patients were treated with eight courses of vincristine and carboplatin. Intensive focal treatments were administered after two courses of chemotherapy.

MAIN OUTCOME MEASURES

Avoidance of external beam radiotherapy (EBRT) and eye survival.

RESULTS

Twenty eyes (74.1%) were classified as Reese-Ellsworth Group V. All eyes responded to chemotherapy. With a median follow-up of 23 months (range 10 to 33 months) and a median of 5.5 focal treatments per eye (range 0 to 19 treatments), ocular survival was 81%. Eight eyes (30%) in five patients received EBRT.

CONCLUSIONS

Vincristine and carboplatin combined with intensive focal treatments is an effective regimen for patients with intraocular retinoblastoma. This treatment regimen has outcomes comparable to those of more toxic regimens and merits further evaluation.

Continuing challenges in the management of retinoblastoma with chemotherapy

The management of retinoblastoma has gradually changed over the past 10 years. Over 95% of children with retinoblastoma in the United States are cured with modern techniques. The challenge remains, however, in maintaining the eye and vision. There is a trend away from enucleation and external beam radiotherapy toward focal conservative treatments involving primary chemoreduction in conjunction with thermotherapy and cryotherapy. This is related to earlier detection of the disease, recognition of more effective chemotherapeutic agents, more focused local treatment modalities, and, most importantly, knowledge of the long-term risks of external beam radiotherapy. Enucleation is still preferable for retinoblastoma that fills most of the eye, especially when the disease is unilateral or when there is concern for tumor invasion into the optic nerve, choroid, or orbit. The orbital integrated implant is placed after enucleation and provides acceptable prosthesis motility and appearance. External beam radiotherapy is still vital for treating advanced retinoblastoma, especially when there is diffuse vitreous or subretinal seeding after failure of other methods and preservation of vision is a priority. The most important recent advance in the management of retinoblastoma is the use of intravenous chemotherapy for tumor reduction, a technique of neoadjuvant chemotherapy termed "chemoreduction." This is followed by tumor consolidation with focal measures such as thermotherapy, cryotherapy, and plaque radiotherapy. This strategy provides reduced tumor volume and often permits consolidation with methods other than radiotherapy. It appears that vision can be preserved in some cases with these methods, avoiding some of the local complications like radiation cataract or macular edema that have been found with radiotherapy techniques. External beam radiotherapy and enucleation can now be avoided in most cases of Reese-Ellsworth groups I (minimal disease) through IV (moderate disease) retinoblastoma. The most advanced stage of retinoblastoma, Reese-Ellsworth group V, continues to provide the greatest difficulty for management, and external beam radiotherapy and enucleation are often employed in addition to chemoreduction to save the child's life. A collaborative prospective study in North America is currently under way to further study the benefits and risks of chemoreduction for minimal, moderate, and advanced retinoblastoma.

Conservative therapy in intraocular retinoblastoma: response/recurrence rate

PURPOSE

To evaluate the response/recurrence rate and the outcome in intraocular retinoblastoma treated with chemoreduction and focal therapy, the authors performed a retrospective review of their patients.

METHODS

The series included 46 newly diagnosed patients with unilateral or bilateral intraocular retinoblastoma (58 eyes) receiving carboplatin/etoposide chemotherapy associated with focal therapy (laser or cryotherapy). The mean follow-up was 53 months (range 11-125).

RESULTS

Fifty-one eyes (88%) presented with complete response after four to eight courses of chemotherapy combined with focal treatment. The response rate was 100% in group 1, 94% in group 2, 100% in group 3, 83% in group 4, and 70% in group 5 (5 vs. 1-4, P < 0.03; 5-4 vs. 1-3, P < 0.025). Twenty-nine eyes (57%) relapsed after a mean of 7 months (range 2-36). The relapse rate was 30% in group 1, 27.% in group 2, 67% in group 3, 80% in group 4, and 100% in group 5 (5 vs. 1-4, P < 0.001; 4-5 vs. 1-3, P < 0.001). Seven of 18 cases achieved a second complete response with further conservative treatment (total courses 8-14). Twenty-nine eyes (50%) were treated without external-beam radiotherapy or enucleation: 90% in group 1, 69% in group 2, 67% in group 3, 33% in group 4, and 6% in group 5 (5 vs. 1-4, P < 0.01; 5-4 vs. 1-3, P < 0.001). Ten eyes (17%) required external-beam radiotherapy and 21 eyes (36%) enucleation. The ocular salvage rate was 67%.

CONCLUSIONS

Although all groups of patients with intraocular retinoblastoma responded to carboplatin/etoposide chemotherapy associated with focal therapy, all the cases in group 5 relapsed. This approach is questionable in group 5, in which could be justified to delay aggressive treatment in a very young child.

Causes of chemoreduction failure in retinoblastoma and analysis of associated factors leading to eventual treatment with external beam radiotherapy and enucleation

PURPOSE

To evaluate the causes of chemoreduction failure in retinoblastoma and to analyze the associated factors for eventual treatment with external beam radiotherapy and enucleation.

DESIGN

Prospective noncomparative case series.

PARTICIPANTS

Seventy-one patients with 105 eyes with intraocular retinoblastoma that underwent chemoreduction therapy between October 1998 and January 2003.

INTERVENTION

A 6-treatment cycle of chemoreduction therapy with vincristine, etoposide, and carboplatin was administered at monthly intervals. Unresponsive disease was defined as persistence of retinal tumors, vitreous seeds, or subretinal seeds after the second treatment cycle, with no appreciable sign of regression. Eyes with unresponsive disease were enucleated after the second treatment. Eyes that responded to chemoreduction therapy received focal treatment, including indirect laser photocoagulation, transpupillary thermotherapy, cryotherapy, and ruthenium 106 episcleral plaque radiotherapy after the second chemoreduction treatment, if necessary, to achieve complete tumor regression. Recurrence was defined as the regrowth of retinal tumors, vitreous or subretinal seeds after an initial favorable response, and regression. Recurrent retinal tumor, vitreous seeds, or subretinal seeds were treated with focal treatments and 2 to 3 additional chemoreduction treatments. When these methods failed or were not applicable, external beam radiotherapy and/or enucleation was administered.

MAIN OUTCOME MEASURES

The use of external beam radiotherapy and enucleation for chemoreduction failure, which was defined as unresponsive or recurrent disease.

RESULTS

The mean follow-up was 25.7 months (range: 6-49). Ten of 105 eyes (9.5%) with unresponsive disease were enucleated after the second treatment. Of the remaining 95 eyes, 42 (44.2%) developed recurrence after chemoreduction. Recurrent disease failing to be treated successfully by other methods was treated with external beam radiotherapy in 26 of 95 eyes (27.4%) and enucleation in 22 of 95 eyes (23.2%). External beam radiotherapy was successful in preventing enucleation in 20 of 26 eyes (76.9%). Overall, the globe salvage rate was 69.5%, ranging from 36.1% for Reese-Ellsworth group V disease to 87.0% for groups I to IV disease. Histopathologically, 29 of 31 enucleated eyes (93.5%) had poorly differentiated or moderately differentiated retinoblastoma. Using multivariate logistic regression analysis, factors predictive of eventual treatment with external beam radiotherapy were female gender (P = 0.010), presence of subretinal seeds (P = 0.023), and a greater number of chemoreduction treatments (P = 0.027). By multivariate analysis, the factors associated with the need for eventual treatment with enucleation were recurrence of retinal tumors (P = 0.004), presence of vitreous seeds (P = 0.008), greater tumor thickness (P = 0.015), presence of subretinal fluid (P = 0.040), and older patient age (P = 0.042).

CONCLUSIONS

Chemoreduction failure in this article was defined as unresponsive or, more commonly, recurrent retinoblastoma. Older patient age, greater tumor thickness, presence of vitreous seeds and subretinal fluid at baseline, and retinal tumor recurrence after chemoreduction were factors associated with the need for enucleation.

Chemoreduction for retinoblastoma. Analysis of tumor control and risks for recurrence in 457 tumors

PURPOSE

To evaluate retinoblastoma control following chemoreduction.

DESIGN

Interventional case series.

METHODS

Prospective.

SETTING

Single center trial.

PATIENT POPULATION

457 retinoblastomas in 193 eyes of 125 patients. Nonrandomized, noncomparative study.

INTERVENTION

All patients received intravenous vincristine, etoposide, and carboplatin,. The tumors were managed with chemoreduction alone (group W) or chemoreduction combined with thermotherapy (group X), cryotherapy (group Y), or both thermotherapy and cryotherapy (group Z).

MAIN OUTCOME MEASURE

Tumor recurrence in each treatment group.

RESULTS

Of 457 retinoblastomas, 63 (14%) were in group W, 256 (56%) in group X, 127 (28%) in group Y, and 11 (2%) in group Z. The tumor was located in the macula in 33 (52%) of group W, 109 (43%) of group X, 3 (2%) of group Y, and 9 (1%) of group Z. The mean tumor thickness at initial examination was 7 mm for group W, 4 mm for group X, 2 mm for group Y, and 3 mm for group Z. Using Kaplan-Meier estimates, recurrence of the individual retinoblastoma at 7 years was found in 45% of group W and 18% for combined groups X, Y, and Z. Risk factors predictive of tumor recurrence by multivariate analysis included macular tumor location for all groups and additionally female gender for group W and increasing tumor thickness for groups X, Y, and Z.

CONCLUSIONS

Chemoreduction alone or combined with cryotherapy or thermotherapy is effective for treatment of retinoblastoma, but tumor recurrence rate is highest for those located in the macula and those with greater thickness.

Intensity-modulated Radiation Therapy for Children with Intraocular Retinoblastoma:Potential Sparing of the Bony Orbit

AIMS

We have evaluated the potential for intensity-modulated radiation therapy (IMRT) to reduce dose to surrounding normal tissues in children with retinoblastoma confined to the globe of the eye.

MATERIALS AND METHODS

Treatment planning computed tomography (CT) scans from five children were used for comparison of four radiotherapy techniques to treat the eye. IMRT, conformal, anterior-lateral photon and en face electron plans were generated using the Corvus (NOMOS) and PLUNC treatment planning systems. Doses to surrounding critical structures were compared after normalisation of target coverage.

RESULTS

The IMRT treatment technique allowed the greatest sparing of the surrounding bony orbit, with an average of 60% of the ipsilateral bony orbit treated above 20 Gy and 48% treated above 24 Gy when 45 Gy is prescribed to the globe. IMRT techniques reduced dose to the surrounding bony orbit by more than one-third compared with anterior-lateral photon and electron techniques, and by 23% compared with conformal techniques. The application of IMRT also reduced dose to other surrounding normal tissues, including the temporal lobe and contralateral orbit.

CONCLUSION

IMRT shows potential for protecting normal tissues in patients requiring external beam radiation therapy for retinoblastoma.

Treatment of intraocular retinoblastoma with vincristine and carboplatin

PURPOSE

To evaluate the efficacy of chemoreduction using vincristine and carboplatin in preventing or delaying external-beam radiotherapy (EBRT) or enucleation in patients with intraocular retinoblastoma.

PATIENTS AND METHODS

Twenty-five patients (43 eyes) with newly diagnosed intraocular retinoblastoma received primary treatment with eight courses of vincristine and carboplatin. Focal treatments were delayed until documentation of disease progression. Outcome measures for each eye were length of time to disease progression, avoidance or delay of EBRT, and globe survival. Event-free survival was defined as the length of time to EBRT or enucleation.

RESULTS

Disease in all eyes responded to chemotherapy and progressed in only two patients before completion of the eight courses of therapy. Disease in all but four eyes progressed and required focal treatments. Event-free survival estimates at 2 years were 59.2% +/- 12.0% for Reese-Ellsworth group I, II, and III eyes and 26.3% +/- 9.2% for group IV and V eyes. Nineteen eyes (44.2%) required EBRT and 13 eyes (30.2%) were enucleated. The ocular salvage rate was 83.3% for Reese-Ellsworth group I to III eyes and 52.6% for group IV and V eyes. For those patients receiving EBRT, the median time from enrollment to EBRT was 9.5 months (median age at EBRT, 21 months).

CONCLUSION

In combination with appropriate early intensive focal treatments, chemoreduction with vincristine and carboplatin, without etoposide, may be an alternative treatment for patients with early-stage intraocular retinoblastoma, although additional studies are needed. Patients with advanced intraocular disease require more aggressive treatments.

Current treatment of retinoblastoma

Chemotherapy has recently achieved a major role in the primary management of intraocular retinoblastoma. Tumor reduction by first-line chemotherapy (chemoreduction) followed by local treatments is now accepted as treatment strategy for intraocular retinoblastoma with the goal of avoiding external beam radiotherapy (EBRT) or enucleation. Although efficient in reducing tumor volume, chemotherapy cannot cure retinoblastoma. Different chemoreduction protocols are used to shrink the tumor, making it treatable with cryotherapy, laser photocoagulation, thermotherapy, and plaque radiotherapy. Systemic chemotherapy used with local ophthalmic therapies during or after the chemotherapy can eliminate the need for enucleation or external beam radiotherapy in Reese-Ellsworth group 1, 2, or 3 retinoblastoma. This combination is not sufficient to obtain tumor control in most eyes with large tumors and diffuse vitreous and subretinal seeds (Reese-Ellsworth group 4 and 5 tumors), and EBRT or enucleation is eventually required. The resultant visual acuity after globe-conserving therapies in those eyes with Reese-Ellsworth group 4 and 5 tumors is often poor. Preliminary results of a phase I/II study of subconjunctival carboplatin injection are encouraging. Enucleation is still recommended in situations such as eyes containing large tumors, long standing retinal detachment, neovascular glaucoma, pars plana tumor seeding, anterior chamber involvement or choroid, optic nerve or orbital tumor extension, and no expectation for useful vision. Chemoprophylaxis is necessary for patients with tumor extending to the surgical margin of the optic nerve and is likely beneficial in preventing metastases in patients with tumor extending beyond the lamina cribrosa. Intensified chemotherapy with autologous stem cell rescue appears effective for patients with metastatic retinoblastoma.