Low-Dose Chemoreduction for Infants Diagnosed with Retinoblastoma before 6 Months of Age

Utility of carboplatin therapeutic drug monitoring for the treatment of neonate and infant retinoblastoma patients in the United Kingdom

BACKGROUND

Retinoblastoma is the most common intra-ocular malignancy in children and frequently presents in very young patients who commonly require intravenous carboplatin. Delivering this is challenging due to a lack of uniform dosing recommendations, rapid changes in physiological function and the risk of side-effects.

METHODS

We conducted a retrospective review of neonates and infants in the UK with retinoblastoma, who have undergone carboplatin therapeutic drug monitoring (TDM). We report on the pharmacokinetic, treatment efficacy and toxicity data.

RESULTS

In total, 29 patients (median age 5 weeks at treatment onset) underwent a total of 74 TDM guided cycles of chemotherapy, involving real time sampling and dose adjustment. An additional 13 patients underwent TDM sampling to modify doses between cycles. Without the adoption of TDM guided dosing, carboplatin exposures would have been ≥20% outside the target AUC in 38/78 (49%) of treatment cycles. Excellent responses and a reassuringly low incidence of toxicities were observed following dose adjustment, despite the young patient age and the implementation of dose increases in the majority of cases.

CONCLUSIONS

Real time TDM is safe, effective and deliverable for neonates and infants receiving carboplatin for retinoblastoma and should be considered standard of care up to the age of 6 months.

Intravitreal Melphalan for Retinoblastoma: The Impact of Toxicity on Recurrence and Ultimate Globe Salvage

Introduction

Intravitreal melphalan (IVM) has emerged as an efficacious treatment for vitreous seeding in retinoblastoma. Although rarely severe, IVM-related toxicity may be treatment limiting. There is paucity of data on the impact of IVM toxicity on new tumor formation and ultimate globe salvage.

Objectives

To investigate whether the grade of retinal toxicity post-IVM impacts retinal and seeding tumor recurrence, as well as the overall ability to salvage the eye.

Methods

A single-institution retrospective chart review was performed on 47 eyes of 42 patients who received systemic intravenous chemotherapy followed by IVM as salvage treatment for persistent or recurrent vitreous seeding. Chorioretinal toxicity was graded from 0 to 5.

Results

Toxicity grade was inversely associated with the risk of recurrence, where a one-unit increase in toxicity grade correlated with nearly a 54% reduction in the odds of tumor recurrence (OR 0.46 [0.25-0.84], p = 0.01). Similarly, toxicity grade was related to enucleation, where a one-unit increase in toxicity grade was associated with a 31% reduction in the odds of undergoing enucleation (OR 0.69 [0.40-1.18], p = 0.17).

Conclusions

While retinoblastoma therapy aims to limit toxicity, especially visually significant toxicity, eyes with higher grades of post-IVM toxicity are less likely to have retinal and seeding tumor recurrence.

Efficacy of topotecan nanoparticles for intravitreal chemotherapy of retinoblastoma

Retinoblastoma (Rb) is the most common intraocular malignancy in children that accounts for approximately 4% of all pediatric malignancies. Since chemotherapy is a widely practiced treatment for Rb, there is a growing interest in developing new and effective drugs to overcome systemic and local side effects of chemotherapy to improve the quality of life and increase the chances of survival. This study sought to fabricate thiolated chitosan nanoparticles containing topotecan (TPH-TCs-NPs) with a view of enhancing drug loading and release control. This research was also designed to assess the ability of TPH-TCs-NPs to improve cell association, increase treatment efficacy in retinoblastoma cells and xenograft-rat-model of retinoblastoma, and overcome current topotecan hydrochloride (TPH) intravitreal administration challenges, including stability loss and poor cellular uptake. Modified ionic gelation method was optimized to fabricate TPH-TCs-NPs and TPH-TMC-NPs (N-trimethyl chitosan nanoparticles containing TPH). We characterized the NPs and quantified topotecan loading and release against a free TPH standard. The efficacy of TPH-NPs was quantified in human retinoblastoma cells (Y79) by XTT and flow cytometry measurement. In addition, Y79 cells were injected intravitreally in both eyes of immunodeficient wistar albino rats to create a xenograft-rat-model to compare the antitumor effectiveness of TPH-NPs and TPH by intravitreal administration. TPH-NPs complexation was confirmed by EDX, FTIR, and DSC techniques. TPH-TCs-NPs and TPH-TMC-NPs had high encapsulation efficiency (85.23 ± 2 and 73.34 ± 2% respectively). TPH-TCs-NPs showed a mean diameter, polidispersity index, and zeta potential of 25±2 nm, 0.21 ± 0.03 and +12 ± 2 mV, respectively. As a function of dose, TCs and TMC NPs were more efficacious than free topotecan (IC50s 53.17 and 85.88 nM, relative to 138.30 nM respectively, P = 0.012). Kruskal-Wallis test showed a statistically significant difference between the groups. Additionally, a significant difference between the tumor control and TPH-TCs-NPs treated group in xenograft-rat-model ( Range of P-value: 0.026 to 0.035) was shown by Bonferroni post hoc test. The current investigation demonstrated enhanced efficacy and association of TPH-TCs-NPs relative to free TPH in retinoblastoma cells and tumor in vitro and in vivo.

Neonatal retinoblastoma: A study of five cases

PURPOSE:

The purpose was to study the clinical features, treatment, and outcome of retinoblastoma (RB) in neonates.

METHODS:

This was a retrospective study of five patients with RB detected in the 1^st month of life.

RESULTS:

The mean age at diagnosis of RB was 22 days (median, 24 days; range, 14–28 days). There were one female and four males with neonatal RB. Two patients had a known family history of RB, and the tumor was detected by routine fundus screening in these children. Two patients were brought in with complaints of leukocoria and one patient with complaints of red-eye. All patients had an intraocular tumor at presentation. Four patients had bilateral involvement, whereas only one had unilateral involvement. Based on the International Classification of Intraocular Retinoblastoma, the tumors were classified as Group A (n = 2), Group B (n = 3), Group C (n = 1), Group D (n = 1), and Group E (n = 2). Macular involvement was noted in 6 (67%) eyes. The primary treatment included systemic chemotherapy with/without focal treatment in all patients. One patient subsequently underwent secondary enucleation as the globe became phthisical. One child died while on treatment due to pneumonia secondary to chemotherapy-induced neutropenia. Of the four patients who completed treatment, globe salvage was achieved in 6 (86%) eyes over a mean follow-up period of 89 months (median, 92 months; range, 29–144 months).

CONCLUSION:

Neonatal RB though rare, if detected early, has a favorable outcome of ocular and life salvage. Sporadic RB can occur in neonates, and a family history may not always be elicited.

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.

Posterior Vitreous Detachment and the Associated Risk of Retinal Toxicity with Intravitreal Melphalan Treatment for Retinoblastoma

BACKGROUND/AIMS

The presence of a posterior vitreous detachment (PVD) may play a role in the development of severe retinal toxicity following intravitreal melphalan (IVM) injection for vitreous seeding. We aimed to evaluate the incidence of PVD in retinoblastoma eyes and its association with retinal toxicity after IVM.

METHODS

We reviewed 112 eyes of 81 retinoblastoma patients with B-scan images available for review from 2010 to 2017. A cohort with vitreous seeding treated with IVM was compared to a cohort that did not undergo injection. The primary outcome measure was the presence of PVD at diagnosis and after treatment. Secondary measures included IVM-associated retinal toxicity and other ocular complications.

RESULTS

The incidence of PVD was 20% at diagnosis, and in eyes with B-scans available both at diagnosis and after treatment 18% of eyes developed a PVD over the course of therapy, more frequently after IVM (p = 0.05). Of 34 eyes receiving IVM treatment, the incidences of posterior segment toxicity and globe salvage were similar between eyes with and without PVD (p = 0.4015 and 0.52, respectively).

CONCLUSION

In this cohort of patients, there did not appear to be an association with the presence of PVD during IVM and the development of retinal toxicity.

Lurking below: massive choroidal invasion under a calcified tumor after attempted conservative therapy for retinoblastoma

BACKGROUND

In the conservative management of retinoblastoma, detection of tumor activity beneath large, calcified tumors presents a challenging aspect of care as local consolidation is limited in this area. Routine imaging modalities, including magnetic resonance imaging, B-scan ultrasound, and optical coherence tomography, are also limited in providing appropriate surveillance for recurrent disease.

MATERIALS AND METHODS

Medical records were reviewed to evaluate patients' demographic data, ophthalmic exams, imaging studies, and histopathologic reports.

RESULTS

Three patients (two females and one male) were diagnosed with retinoblastoma (two bilateral and one unilateral) and managed with intravenous chemotherapy and local consolidation. In all three cases, the initial tumors regressed to form large, predominantly calcified tumors. However, it was observed that there continued to be nodular recurrences on the surface of the calcium without visible clinical activity at the base of the calcified lesion. All three cases ultimately required enucleation for these active nodular recurrences and massive choroidal invasion was noted under the calcified tumor. Ophthalmic exams and imaging studies did not provide consistent indication of choroidal disease in these cases, and the extensive calcification prevented detection of active disease at the tumor base on fundoscopy.

CONCLUSIONS

Active choroidal disease at the base of large, calcified tumors cannot be ruled out with ophthalmologic examination and noninvasive imaging; suspicion of disease activity at the base should remain high for patients presenting with multiple recurrent nodules over a calcified tumor.

Integrated Treatment during the Intravitreal Melphalan Era: Concurrent Intravitreal Melphalan and Systemic Chemoreduction

Background

Intravitreal injection of melphalan (IVM) is safe and effective for the treatment of seeding in retinoblastoma. Current protocols require weekly injections during examination under anesthesia (EUA). To avoid additional anesthesia exposure for these children, IVM was initiated at the EUA concurrent with the 4th cycle of systemic chemoreduction in a series of 6 patients with persistent seeding.

Methods

A retrospective review was completed to assess treatment response compared to all patients at our center treated with IVM and systemic chemotherapy. Overall, 6 eyes of 6 patients were included; salvage therapy included systemic chemoreduction with vincristine, etoposide, and carboplatin and IVM for persistent seeding.

Results

IVM was initiated in all eyes at cycle 4 of their chemotherapy. Success in eradicating vitreous seeds was 100%; overall salvage rate was 67%. Anterior toxicity was observed in 2 out of 6 eyes and posterior toxicity in 4 out of 6 eyes.

Conclusion

The concurrent chemoreduction and IVM protocol demonstrated a similar efficacy of globe salvage while sparing children additional EUAs. However, the increased rates of observed melphalan-related toxicities for concurrent therapy are concerning. Further clinical experience is necessary to define the best initiation time and dosing schedule for IVM.

Long-term outcomes of Group D retinoblastoma eyes during the intravitreal melphalan era

BACKGROUND

To evaluate outcomes of Group D retinoblastoma (Rb) eyes during the intravitreal melphalan era.

PROCEDURE

Retrospective chart review of patients diagnosed with Group D Rb from 2011 to 2016 was done. Overall, 76 Group D eyes of 68 patients were included; salvage therapy included systemic chemoreduction with vincristine, etoposide, and carboplatin with local consolidation, followed by intravitreal injection of melphalan for recurrent or persistent seeding. External beam radiation was not used as a treatment modality. Primary outcome measurement was globe salvage.

RESULTS

Of 76 Group D eyes, 24 were enucleated primarily and 52 were treated with intent to salvage the globe. Systemic chemoreduction salvaged 25 of 52 eyes (48%). Tumor recurrences were diagnosed in 27 eyes (52%); five with massive retinal recurrences underwent enucleation and 22 were treated with intravitreal melphalan injection. Of the 22 injected eyes, 14 (64%) were salvaged and eight required enucleation primarily for retinal recurrences. Success in eradicating vitreous seeds was 100%. The Kaplan-Meier 3-year survival estimate for treated eyes is 76.5% (95% CI: 61.4-86.3). Median follow-up for the group of 76 Group D eyes was 29.5 months (SD 17.9 months).

CONCLUSION

During a 6-year period that included the initiation of intravitreal melphalan at our institution, the salvage rate of treated Group D eyes was 75% (39/52 eyes). Intravitreal melphalan was utilized for ocular salvage in 42% (22/52 eyes). Systemic chemoreduction combined with intravitreal melphalan for seeding demonstrated a high overall salvage rate for Group D eyes in this cohort.

Potential of Aqueous Humor as a Surrogate Tumor Biopsy for Retinoblastoma

Importance

Retinoblastoma (Rb) is one of the first tumors to have a known genetic etiology. However, because biopsy of this tumor is contraindicated, it has not been possible to define the effects of secondary genetic changes on the disease course.

Objective

To investigate whether the aqueous humor (AH) of Rb eyes has sufficient tumor-derived DNA to perform genetic analysis of the tumor, including DNA copy number alterations.

Design, Setting, and Participants

This investigation was a case series study at a tertiary care hospital (Children's Hospital Los Angeles) with a large Rb treatment center. Cell-free DNA (cfDNA) was isolated from 6 AH samples from 3 children with Rb, including 2 after primary enucleation and 1 undergoing multiple intravitreous injections of melphalan for vitreous seeding. Samples were taken between December 2014 and September 2015.

Main Outcomes and Measures

Measurable levels of nucleic acids in the AH and identification of tumor-derived DNA copy number variation in the AH. The AH was analyzed for DNA, RNA, and micro-RNA using Qubit high-sensitivity kits. Cell-free DNA was isolated from the AH, and sequencing library protocols were optimized. Shallow whole-genome sequencing was performed on an Illumina platform, followed by genome-wide chromosomal copy number variation profiling to assess the presence of tumor DNA fractions in the AH cfDNA of the 3 patients. One child's cfDNA from the AH and tumor DNA were subjected to Sanger sequencing to isolate the RB1 mutation.

Results

Six AH samples were obtained from 3 Rb eyes in 3 children (2 male and 1 female; diagnosed at ages 7, 20, and 28 months). A corroborative pattern between the chromosomal copy number variation profiles of the AH cfDNA and tumor-derived DNA from the enucleated samples was identified. In addition, a nonsense RB1 mutation (Lys→STOP) from 1 child was also identified from the AH samples obtained during intravitreous injection of melphalan, which matched the tumor sample postsecondary enucleation. Sanger sequencing of the AH cfDNA and tumor DNA with polymerase chain reaction primers targeting RB1 gene c.1075A demonstrated this same RB1 mutation.

Conclusions and Relevance

In this study evaluating nucleic acids in the AH from Rb eyes undergoing salvage therapy with intravitreous injection of melphalan, the results suggest that the AH can serve as a surrogate tumor biopsy when Rb tumor tissue is not available. This novel method will allow for analyses of tumor-derived DNA in Rb eyes undergoing salvage therapy that have not been enucleated.

Not All Seeds Are Created Equal: Seed Classification Is Predictive of Outcomes in Retinoblastoma

OBJECTIVE

Intravitreal chemotherapy has emerged as an important modality for treating vitreous seeding in retinoblastoma. A classification system has been described as predictive of response to intravitreal melphalan (IVM) in patients treated predominantly with primary intra-arterial chemotherapy. The objective of this study is to evaluate the outcomes of retinoblastoma treated with intravenous chemotherapy and IVM as salvage for vitreous seeding, and further to determine whether vitreous seed classification (dust, spheres, cloud) is predictive of the total number and dose of IVM injections required for treatment in this cohort.

DESIGN

A nonrandomized retrospective review.

PARTICIPANTS

Retinoblastoma patients treated at a single center with intravenous chemotherapy and IVM.

METHODS

Retrospective review of patients with vitreous seeding from retinoblastoma treated with intravenous chemotherapy and IVM from 2012 to 2016.

MAIN OUTCOME MEASURES

Primary outcome measure was eradication of seeds and globe salvage. Secondary measures included IVM-associated toxicity and complications.

RESULTS

Overall, 28 eyes of 25 patients were included, with a total of 110 IVM injections. By seed classification, eyes with dust (n = 15) required a median of 3 injections, spheres (n = 8) required 4 injections, and clouds (n = 5) required 6 injections. Spherical seeds were only seen in recurrent vitreous seeding. Of the 28 treated eyes, 9 were enucleated, 6 for recurrent retinal disease, resulting in an overall globe salvage rate of 68%. The salvage rate secondary to active retinoblastoma was 79%. Dust classification was the most prevalent seeding type of the 9 enucleated eyes. There was 100% regression of vitreous seeds after intravitreal injection and no eye was treated with radiation or enucleated for seeding. Twelve eyes demonstrated grade 3 or greater IVM-associated retinal or anterior segment toxicity post injection. Mean follow-up was 33 months (range, 9-51 months).

CONCLUSIONS

IVM is an effective treatment for vitreous seeding after intravenous chemotherapy for retinoblastoma. As with eyes treated with intra-arterial chemotherapy, seed classification is predictive of the total number and dose of IVM injections in eyes treated with intravenous chemotherapy. Eyes with clouds required significantly more injections than eyes with dust or spheres.

Clinical Significance of Optic Nerve Enhancement on Magnetic Resonance Imaging in Enucleated Retinoblastoma Patients

PURPOSE

The aim of this 8-year retrospective review was to determine the clinical significance of gadolinium-enhanced magnetic resonance imaging (MRI) findings in retinoblastoma patients after enucleation, particularly the presence of abnormal contrast enhancement of the transected optic nerve.

DESIGN

Retrospective chart review.

SUBJECTS

A review was done on 88 patients with retinoblastoma undergoing 90 enucleations between January 2008 and December 2015.

METHODS

These patients underwent 233 MRI scans: 90 preoperative and 143 postoperative that were included for review.

MAIN OUTCOME MEASURE

The primary outcome measure assessed was abnormal MRI findings in the preoperative and postoperative MRI scans, specifically enhancement of the optic nerve and correlations between abnormal MRI findings and clinical outcomes for the 88 patients.

RESULTS

On the preoperative MRI, 4 optic nerves out of 90 scans showed positive enhancement. Fifty orbits had ≥1 postoperative MRI. Overall, 41 of 50 orbits (82%) of enucleated patients demonstrated postoperative contrast enhancement on MRI after enucleation, at a mean interval of 10 months after surgery. The percentage of MRI scans with optic nerve enhancement was 77% from 0 to 6 months after enucleation and 68% at >24 months after surgery. Postenucleation optic nerve enhancement did not correlate with preoperative optic nerve enhancement, chemotherapy administration, or the presence of optic nerve invasion on histopathology. No child required an orbital biopsy. None of the 88 patients were found to have subsequent orbital or metastatic disease at the last clinical follow-up visit (average, 29 months; range, 1-71).

CONCLUSION

Optic nerve contrast enhancement on follow-up MRI after enucleation for retinoblastoma seems to be a common, benign radiographic finding; none of the patients in this series developed extraocular tumor relapse. The presence of postenucleation enhancement on MRI did not correlate with preoperative chemotherapy or the presence of optic nerve invasion on histopathology. Based on our findings, intervention for isolated optic nerve enhancement on MRI is not indicated in the absence of other abnormal clinical or radiographic signs. A prospective trial with a validated radiographic grading system would be helpful to clarify the MRI features to differentiate orbital recurrence from benign postoperative enhancement.

Optic Nerve Obscuration in Retinoblastoma: A Risk Factor for Optic Nerve Invasion?

Background

The objective of this study is to evaluate the risk of optic nerve invasion associated with optic nerve obscuration at diagnosis or persisting during treatment.

Methods

Retrospective review from 2011-2016 of patients with advanced retinoblastoma (Group D/E) with complete obscuration of the nerve at diagnosis and a second group of patients with persistent, complete obscuration throughout treatment.

Results

Advanced retinoblastoma was diagnosed in 102 eyes of 86 patients. The optic nerve was obscured in 69 eyes (68%) at diagnosis. Of these, 30 (43%) underwent salvage therapy and 39 (57%) primary enucleation. Histopathologic analysis of primarily enucleated eyes showed 41% prelaminar and 15% postlaminar invasion. Four eyes in the salvage group demonstrated persistent nerve obscuration; 2 were subsequently enucleated without evidence of nerve invasion. Average follow-up was 23.5 months (range 1-62 months).

Conclusions and Relevance

Optic nerve obscuration at diagnosis may be associated with postlaminar optic nerve invasion. While persistent, complete obscuration of the optic nerve by retinoblastoma during treatment is a poor prognostic sign for both globe salvage and vision, it does not appear, in this small cohort, to increase the risk of optic nerve invasion. With appropriate control of the intraocular tumor, these eyes can be salvaged.

Risk of metastasis and orbital recurrence in advanced retinoblastoma eyes treated with systemic chemoreduction versus primary enucleation

BACKGROUND

The purpose of this study was to evaluate the risk of metastatic disease and orbital recurrence in advanced retinoblastoma treated with systemic chemoreduction versus primary enucleation.

METHODS

A retrospective review of patients with Group D/E retinoblastoma was conducted with data collection from 1995 to 2015. Overall, 345 eyes (294 patients) were included (165 Group D and 180 Group E). Primary outcome measures were orbital recurrence and metastatic disease.

RESULTS

Of the 345 eyes, 139 were treated with systemic chemoreduction (102 Group D, 37 Group E) and 206 with primary enucleation (63 Group D, 143 Group E). In the chemoreduction group, one patient developed metastasis (0.7%) and one an orbital recurrence (0.7%). In the primary enucleation group, two patients developed metastases (0.9%) and one an orbital recurrence (0.5%). After systemic chemoreduction, 58 of the 139 eyes (30 Group D, 28 Group E) were secondarily enucleated for treatment failure (41.7%). The median time to secondary enucleation from diagnosis was 8.1 months. None of the eyes in the systemic chemoreduction group had high-risk pathologic features. In the primary enucleation group, 56 eyes had high-risk pathology.

CONCLUSION

Over a 20-year period, 345 eyes were treated for advanced retinoblastoma at Children's Hospital Los Angeles. Incidence of orbital recurrence and metastatic disease was <1% and did not vary by treatment modality or group classification. None of the eyes enucleated for treatment failure had high-risk pathology, and none of these patients developed metastatic disease. Globe salvage therapy with systemic chemoreduction and subsequent enucleation for poor response does not increase the risk of metastatic disease or orbital recurrence.

Long-Term Outcomes of Group B Eyes in Patients with Retinoblastoma Treated with Short-Course Chemoreduction: Experience from Children's Hospital Los Angeles/University of Southern California

BACKGROUND/AIMS

Chemoreduction protocols for retinoblastoma vary widely across institutions. Herein, we compare a 3- versus 6-cycle chemotherapy approach for group B retinoblastoma.

METHODS

A nonrandomized, retrospective review of patients diagnosed with group B retinoblastoma from 1991-2011 at Children's Hospital Los Angeles was performed. A total of 72 eyes of 63 patients were analyzed. Mean follow-up time was 82 months (range 6-272 months). Main outcome measures were globe salvage and need for external beam radiation.

RESULTS

Forty-six patients (55 eyes) were treated upfront with 3 cycles of carboplatin, etoposide, and vincristine; 17 patients (17 eyes) received 6 cycles. Thirty-seven eyes (67%) in the 3-cycle group were cured with initial chemoreduction alone. An additional 10 eyes with persistent or recurrent tumors were rescued with 3 more cycles for a total salvage rate of 85% (47/55 eyes). In the 6-cycle group, 16 of 17 eyes (94%) avoided radiation and enucleation.

CONCLUSION

The initial recurrence rate was higher for the 3-cycle group (p = 0.03). However, eyes failing short-course chemoreduction were rescued with 3 additional cycles and achieved a similar overall event-free survival rate (p = 0.16). In our cohort, this short-course approach spared 63% (29/46) of patients with group B retinoblastoma the extra 3 cycles of systemic chemotherapy.