Minimal exposure (one or two cycles) of intra-arterial chemotherapy in the management of retinoblastoma

Retinoblastoma - A comprehensive review, update and recent advances

Retinoblastoma is the most common pediatric ocular malignancy. It is triggered by a biallelic mutation in the RB1 gene or MYCN oncogene amplification. Retinoblastomas can be unilateral (60%-70%) or bilateral (30%-40%); bilateral tumors are always heritable and present at an earlier age as compared to unilateral ones (18-24 months vs. 36 months in India). High prevalence rates, delayed presentation, and inaccessibility to healthcare lead to worse outcomes in developing countries. The past few decades have seen a paradigm change in the treatment of retinoblastomas, shifting from enucleation and external beam radiotherapy to less aggressive modalities for eye salvage. Multimodality treatment is now the standard of care and includes intraarterial or intravenous chemotherapy along with focal consolidation therapies such as transpupillary thermotherapy, cryotherapy, and laser photocoagulation. Intravitreal and intracameral chemotherapy can help in controlling intraocular seeds. Advanced extraocular or metastatic tumors still have a poor prognosis. Genetic testing, counseling, and screening of at-risk family members must be incorporated as essential parts of management. A better understanding of the genetics and molecular basis of retinoblastoma has opened up the path for potential targeted therapy in the future. Novel recent advances such as liquid biopsy, prenatal diagnosis, prognostic biomarkers, tylectomy, and chemoplaque point to promising future directions.

Angiographic characteristics and treatment approach in patients undergoing intra-arterial chemotherapy for retinoblastoma

PURPOSE

To identify the specific clinical and angiographic variables that determine the success of intra-arterial chemotherapy (IAC) in a patient with retinoblastoma.

METHODS

Medical records from patients undergoing intra-arterial chemotherapy for the treatment of retinoblastoma between January 2015 and June 2020 within a large academic ocular oncology practice were retrospectively reviewed. Demographics were recorded together with clinical, ocular, and angiographic variables such as the diameter of the ophthalmic artery (OA), angle of ophthalmic artery takeoff, and branching pattern of ophthalmic vasculature.

RESULTS

Forty-four eyes from 33 patients with retinoblastoma treated with IAC were identified. Over the total 32 mean months of follow-up, these patients received 144 total catheterizations and a mean of 3.2 IAC cycles for each eye. The number of IAC cycles and the chemotherapeutic agent used did not vary significantly with worsening International Classification of Retinoblastoma (ICRB) groups (P > 0.1). Cumulative dose did not vary with the ICRB group for eyes treated with melphalan, topotecan, or carboplatin (P > 0.1). A higher ICRB group was associated with a smaller mean ophthalmic artery diameter across all procedures (P = 0.016), and femoral artery diameter did not vary significantly between ICRB groups (P = 0.906). A higher cumulative dose of IAC was significantly associated with a smaller takeoff angle of the OA (melphalan, P = 0.011; topotecan, P = 0.009; carboplatin, P = 0.031) in patients who underwent successful IAC procedures. Ophthalmic artery diameter and femoral artery diameter did not have a significant association (P > 0.1) with higher IAC doses in successful IACs. Cumulative IAC dose was not significantly associated with ophthalmic vasculature branching pattern, presence of choroidal blush, temporary OA vasospasm reported during the procedure, and OA occlusion upon microcatheter placement.

CONCLUSION

In this study, neurosurgical angioanatomy appeared to influence the cumulative dose of chemotherapy needed during IAC for retinoblastoma. In the future, these anatomic variables may be used to guide the frequency of monitoring, dosing, and estimation of recurrence risk.

Likelihood of germline mutation with solitary retinoblastoma based on tumour location at presentation

BACKGROUND/AIMS

To evaluate the likelihood of germline mutation in patients presenting with solitary retinoblastoma based on tumour location at first examination.

METHODS

Retrospective analysis of solitary unilateral retinoblastoma for likelihood of germline mutation (family history of retinoblastoma and/or genetic testing indicating germline RB1 mutation and/or development of additional new or bilateral tumours) based on tumur location at presentation (macular vs extramacular).

RESULTS

Of 480 consecutive patients with solitary retinoblastoma, 85 were in the macula (18%) and 395 were extramacular (82%). By comparison (macular vs extramacular tumours), macular tumours had smaller basal diameter (12.7 mm vs 18.9 mm, p<0.001) and smaller tumour thickness (6.1 mm vs 10.7 mm, p<0.001). Patients with macular tumours demonstrated greater likelihood for germline mutation (23% vs 12%, OR=2.18, p=0.011), specifically based on family history of retinoblastoma (13% vs 2%, OR=4.64, p=0.004), genetic testing showing germline RB1 mutation (27% vs 15%, OR=2.04 (95% CI 1.04 to 4.01), p=0.039), development of new tumours (13% vs 3%, OR=5.16 (95% CI 2.06 to 12.87), p=0.001) and/or development of bilateral disease (9% vs 2%, OR=4.98 (95% CI 1.70 to 14.65), p=0.004).

CONCLUSIONS

Among patients with solitary unilateral retinoblastoma, those presenting with macular tumour (compared with extramacular tumour) show 2.18 times greater likelihood for germline mutation and an even higher likelihood of development of subsequent tumours. Solitary macular retinoblastoma should raise an index of suspicion for likely germline mutation and multifocal disease.

Recent advancements in the management of retinoblastoma and uveal melanoma

Retinoblastoma in children and uveal melanoma in adults can pose a serious threat to both vision and life. For many decades, enucleation was often the only option to treat these intraocular malignancies. For retinoblastoma, intra-arterial chemotherapy is often utilized as the primary treatment at advanced academic centers and has dramatically improved local tumor control and eye salvage rates. For uveal melanoma, both plaque brachytherapy and proton beam irradiation have served as widely utilized therapies with a local failure rate of approximately 1–10%, depending on the series. Major recent advancements have allowed for a better understanding of the genomics of uveal melanoma and the impact of certain mutations on metastatic susceptibility. Gene expression profile stratifies uveal melanomas into two classes: low-risk (class 1) and high-risk (class 2). A loss-of-function mutation of BAP1 is associated with a class 2 gene expression profile and therefore confers worse prognosis due to elevated risk of metastasis. On the other hand, gain-of-function mutations of EIF1AX and SF3B1 correspond to a gene expression profile of class 1A and class 1B and confer a better prognosis. Preferentially expressed antigen in melanoma (PRAME) is an antigen that increases metastatic susceptibility when expressed in uveal melanoma cells. In addition to plaque brachytherapy and proton beam irradiation, both of which have demonstrated superb clinical outcomes, scientists are actively investigating newer therapeutic modalities as either primary therapy or adjuvant treatment, including a novel nanoparticle therapy and immunotherapy.

The Use of Alternative Routes for the Delivery of Intra-Arterial Chemotherapy for Retinoblastoma

BACKGROUND

The introduction of intra-arterial chemotherapy (IAC) for treatment of retinoblastoma considerably changed the paradigm by which this disease is managed, with event-free survival rates being above 70%.

OBJECTIVE

To analyze efficacy of IAC treatment using alternative approaches to ophthalmic artery catheterization (OAC), such as external carotid artery approach or balloon-assisted drug delivery.

METHODS

This is a retrospective chart review for subjects receiving IAC for retinoblastoma. The primary approach was OAC. In cases in which selective OAC was not feasible, alternative routes including catheterization of the external carotid artery or use of a balloon-assisted drug infusion were used.

RESULTS

This study included 197 consecutive patients with 207 retinoblastomas who underwent 658 IAC procedures overall. The mean age at diagnosis was 24 mo, and 54.5% of the study population was male. Success rate with IAC was 97% (639). Alternative approaches to OAC were, in total, 42 cases (6.4%)-external carotid artery catheterization and use of ICA balloon were performed in 22 (3.3%) and 20 (3%) cases, respectively. A mean of 3.1 IAC cycles were performed for each patient. In total, there were 23 technical failures of the primary OAC technique (3.4%). Periprocedural adverse events occurred in 4 procedures (0.6%). Use of an alternative technique for chemotherapy delivery other than selective OAC in at least one IAC cycle was not a predictor of enucleation.

CONCLUSION

IAC is a safe and effective treatment option for retinoblastoma. Chemotherapy delivery using alternative techniques is as effective as selective OAC.

Correlation of Technical and Adjunctive Factors with Quantitative Tumor Reduction in Children Undergoing Selective Ophthalmic Artery Infusion Chemotherapy for Retinoblastoma

BACKGROUND AND PURPOSE

Selective ophthalmic artery infusion chemotherapy has improved ocular outcomes in children with retinoblastoma. Our aim was to correlate quantitative tumor reduction and dichotomous therapeutic response with technical and adjunctive factors during selective ophthalmic artery infusion chemotherapy for retinoblastoma. An understanding of such factors may improve therapeutic efficacy.

MATERIALS AND METHODS

All patients with retinoblastoma treated by selective ophthalmic artery infusion chemotherapy at a single center during a 9-year period were reviewed. Only first-cycle treatments for previously untreated eyes were studied. Adjunctive factors (intra-arterial verapamil, intranasal oxymetazoline external carotid balloon occlusion) and technical factors (chemotherapy infusion time, fluoroscopy time) were documented by medical record review. Quantitative tumor reduction was determined by blinded comparison of retinal imaging acquired during examination under anesthesia before and 3-4 weeks after treatment. The dichotomous therapeutic response was classified according to quantitative tumor reduction as satisfactory (≥ 50%) or poor (<50%).

RESULTS

Twenty-one eyes met the inclusion criteria. Patients ranged from 2 to 59 months of age. Adjuncts included intra-arterial verapamil in 15, intranasal oxymetazoline in 14, and external carotid balloon occlusion in 14. Quantitative tumor reduction ranged from 15% to 95%. Six showed poor dichotomous therapeutic response. A satisfactory dichotomous therapeutic response was correlated with intra-arterial verapamil (P = .03) in the aggregate cohort and in a subgroup undergoing treatment with single-agent melphalan at a dose of <5 mg (P = .02). In the latter, higher average quantitative tumor reduction correlated with intra-arterial verapamil (P < .01).

CONCLUSIONS

Intra-arterial verapamil during selective ophthalmic artery infusion chemotherapy is correlated with an improved therapeutic response, particularly when treating with lower doses of single-agent melphalan.

Intra-arterial Chemotherapy as Primary Treatment for Cavitary Retinoblastoma: Excellent Response in Eight Tumors

PURPOSE

The "cavitary" form of retinoblastoma has historically demonstrated minimal treatment response with intravenous chemoreduction, showing less robust regression and less reduction in tumor size. Intra-arterial chemotherapy (IAC) has been reported to more effectively treat retinoblastoma, allowing many previously unsalvageable eyes to now be saved. The purpose was to report treatment response of cavitary retinoblastoma tumors to IAC.

DESIGN

Retrospective case series.

PARTICIPANTS

Patients presenting with cavitary retinoblastoma who were treated with IAC.

METHODS

Retrospective case series of all patients presenting with cavitary retinoblastoma between August 2014 and January 2019 who were treated with primary IAC.

MAIN OUTCOME MEASURES

Tumor regression, recurrence, resolution of vitreous and subretinal seeds, number of treatments required, globe salvage, metastasis, and death.

RESULTS

Eight cavitary retinoblastoma tumors in 6 eyes of 4 patients were treated with IAC. One hundred percent of the cavitary tumors regressed (8/8 tumors, in 6/6 eyes), and 100% of vitreous and subretinal seeds regressed, with 100% globe salvage. None of the tumors recurred, no patients developed metastases, and no patients died. Eyes were treated with a median of 4.5 cycles of IAC (range, 1-7), with fewer IAC treatments used in the later patients (1-3 treatments per eye for the most recent 3 eyes, compared with 6-7 treatments per eye for the earliest 3 eyes). Mean reduction in thickness was 73.4% (range, 59.7%-84.6%). Mean reduction in basal diameter was 45.5% (range, 24.8%-56.0%).

CONCLUSIONS

Treatment with IAC results in regression of cavitary retinoblastoma, often with greater reduction in tumor size than has been reported previously with intravenous chemotherapy (IVC). Using up-front triple therapy (e.g., melphalan 0.4 mg/kg, carboplatin 50 mg, and topotecan 2 mg) and noting certain subtle signs of early regression can help to minimize unnecessary additional cycles of treatment.

Management of retinoblastoma in older children (>5 years) using intra-arterial chemotherapy: Comparison of outcomes to prechemotherapy and intravenous chemotherapy eras

Purpose:

Intra-arterial chemotherapy (IAC) has emerged as an effective treatment for retinoblastoma (RB) however, little information exists regarding its use in older patients (>5 years). In the present study, we evaluate the use of IAC (2008–2018) for RB in older patients and compare the outcomes to those in the prechemotherapy (<1994) and intravenous chemotherapy (IVC) (1994–2007) eras.

Methods:

A retrospective analysis of all patients older than 5 years treated with IAC for RB from 2008–2018. Comparisons were made to 26 active RB cases in older children treated in the prechemotherapy era and to 12 active RB cases treated in the IVC era.

Results:

There were 13 eyes with RB in 13 older patients treated in the IAC era. The median patient age was 6.8 years. Tumor response was achieved in all 13 eyes at a median interval of 1.1 months from first IAC. Globe salvage was achieved in eight eyes with five eyes requiring enucleation. At 14 months, median follow-up after IAC, there was no metastasis or death. Compared to the prechemotherapy era, those in the IAC era demonstrated significant reduction in need for enucleation (P < 0.001) and EBRT or enucleation (P < 0.001). Compared to the IVC era, there was significant reduction in need for EBRT (P = 0.02) and EBRT or enucleation (P = 0.03) and similar avoidance of metastasis (P > 0.99) and death (P > 0.99).

Conclusion:

Older patients with RB managed in the IAC era demonstrated reduced need for EBRT or enucleation compared to those managed in the IVC or prechemotherapy eras, with no instance of metastasis or death.

Intra-Arterial Chemotherapy for Retinoblastoma in Infants ≤10 kg: 74 Treated Eyes with 222 IAC Sessions

BACKGROUND AND PURPOSE

Intra-arterial chemotherapy for retinoblastoma has dramatically altered the natural history of the disease. The remarkable outcomes associated with a high safety profile have pushed the envelope to offer treatment for patients weighing ≤10 kg. The purpose was to determine the efficacy and safety of IAC infusions performed in infants weighing ≤10 kg with intraocular retinoblastoma.

MATERIALS AND METHODS

A retrospective chart review was performed for patients diagnosed with retinoblastoma and managed with intra-arterial chemotherapy.

RESULTS

The total study cohort included 207 retinoblastoma tumors of 207 eyes in 196 consecutive patients who underwent 658 intra-arterial chemotherapy infusions overall. Of these, patient weights were ≤10 kg in 69 (35.2%) and >10 kg in 127 (64.8%) patients. Comparison (≤10 kg versus >10 kg) revealed that the total number of intra-arterial chemotherapy infusions was 222 versus 436. Periprocedural complications were not significantly different (2 [0.9%] versus 2 [0.5%]; P = .49). Cumulative radiation exposure per eye was significantly lower in infants weighing ≤10 kg (5.0 Gym² versus 7.7 Gym²; P = .01). Patients weighing ≤10 kg had a greater frequency of complete tumor regression (82.6% versus 60.9%; P = .02). Mean fluoroscopy time was not significantly different (7.5 versus 7.2; P = .71). There was a significant difference in the frequency of enucleation (16 [21.6%] versus 52 [39.1%]; P = .01). Patients weighing ≤10 kg had greater number of aborted procedures (12 [5.4%] versus 7 [1.6%]; P = .01). On multivariate analysis, weight ≤10 kg was not an independent predictor of complications or procedure failure.

CONCLUSIONS

Intra-arterial chemotherapy in patients weighing ≤10 kg is a safe and effective treatment.

Ophthalmic artery catheterization for retinoblastoma treatment: does reflux affect tumor response?

Background

Intra-arterial chemotherapy (IAC) for retinoblastoma (Rb) has been established as a primary treatment for the disease. To determine whether the presence of reflux into the ICA is associated with tumor response or with any other adverse events in pediatric retinoblastoma patients.

Methods

A retrospective chart review was performed for patients diagnosed with Rb and managed with ophthalmic artery catheterization (OAC).

Results

The total study cohort included 205 Rb tumors of 205 eyes in 194 consecutive patients who underwent 624 successful intra-arterial chemotherapy infusions using OAC. Of the 205 eyes, 65 eyes (32.7%) underwent 157 OAC procedures constituted group A (no reflux), 64 eyes (31.2%) underwent 236 OAC procedures constituted group B (variable pattern), and 74 eyes (36.1%) underwent 231 OAC procedures constituted group C (reflux). There was no significant difference in baseline characteristics between the three cohorts. Also, there was no significant difference in tumor characteristics between the three groups, except for genetic status. There was no significant difference between the three groups in terms of tumor response at completion of the treatment regimen. Complete tumor response was achieved at 70.2% in Group A, at 83.3% in Group B, and at 78.5% in group C (P=0.39). Similarly, eye enucleation occurred at 38.5% in group A, 31.8% in group B, and 31.5% in group C. None of the patients in both groups had any neurological adverse events or new onset of seizures.

Conclusions

The presence of reflux, which may complicate the procedure and prolong it, was not associated with poor outcomes in our analysis.

Contemporary management of retinoblastoma in the context of a low-resource country

Retinoblastoma (RB) is the most common ocular cancer, and it typically presents before the age of 5 years in over 90% of cases. In high resource countries, RB patients tend to survive and retain their sight. This is not the case in low-resource countries because of late presentation and delayed intervention arising mostly from sociocultural and socioeconomic challenges. RB has no gender or racial predilection; the incidence is estimated as 1:16,000-1:18,000 live-births or 11/1 million children under 5 years. Most of the world's RB cases are found in Asia and Africa while most RB treatment centres are in America and Europe. RB is easy to detect by caregivers as a glowing white 'cat eye reflex' at night or when captured on camera. Health workers at primary care level can detect RB in early life if red reflex test and/or squint (Hirschberg) tests are deployed as part of wellness checks done especially during routine immunisation and well-baby clinics in the first 24 months of life. In most cases of RB, biopsies for histological confirmation are not required for diagnosis and treatment decisions to be made. Clinical information, ophthalmic evaluation and imaging modalities are typically used. There have been significant changes in the management of RB using various treatment modalities such as enucleation with orbital implant, use of chemotherapy delivered through intravenous, intravitreal, periocular and intra-arterial routes and targeted treatment with laser, cryotherapy and brachytherapy. Algorithm for management and development of the national RB program within the context of a low-resource country is presented from review of data extracted from Mendeley library, PubMed library, Google Scholar and One Network; full-text articles were mostly retrieved through the American Academy of Ophthalmology.

USE OF FEMORAL ARTERY ULTRASOUND DURING INTRAARTERIAL CHEMOTHERAPY FOR CHILDREN UNDER 10 KG WITH RETINOBLASTOMA

PURPOSE

To demonstrate the safety and efficacy of intraarterial chemotherapy (IAC) in small infants (<10 kg) with retinoblastoma.

METHODS

Retrospective, consecutive, observational case series of patients treated with IAC. Femoral arterial access was obtained using a micropuncture kit and ultrasound guidance, which enabled direct visualization. Melphalan (1.5-5.0 mg), topotecan (0.3-2.0 mg), and/or carboplatin (30-40 mg) were used. Patients underwent adjuvant therapies including laser, cryotherapy, and intravitreal melphalan if persistent disease or recurrence was observed.

RESULTS

Fifty-nine injections were administered to 11 eyes of 6 patients. All eyes but one were classified as International Classification Groups C or D. Median patient weight at first IAC cycle was 9.2 kg (mean, 8.9 kg). Median diameter of the femoral artery at the catheterization site was 3.74 mm, measured by two independent observers. Median follow-up was 21.4 months (range 13.1-34.5 months). All eyes were salvaged.

CONCLUSION

This study confirmed the safety and efficacy of IAC in infants under 10 kg. Ultrasound guidance enabled successful catheterization of femoral arteries as small as 2.7 mm in diameter. Patients in this study appeared to require fewer injections and lower total doses of chemotherapy compared with previously reported series of comparably advanced disease in larger infants.

Recent advancements in the management of retinoblastoma and uveal melanoma

Retinoblastoma and uveal melanoma are the most common intraocular malignancies observed in pediatric and adult populations, respectively. For retinoblastoma, intra-arterial chemotherapy has dramatically improved treatment outcomes and eye salvage rates compared with traditional salvage rates of systemic chemotherapy and external beam radiation therapy. Intravitreal injections of chemotherapy have also demonstrated excellent efficacy for vitreous seeds. Uveal melanoma, on the other hand, is treated predominantly with iodine-125 plaque brachytherapy or with proton beam therapy. Major strides in uveal melanoma genomics have been made since the early 2000s, allowing ocular oncologists to better understand the metastatic risks of the tumor on the basis of specific genetic signatures. Loss-of-function mutations of the BAP1 gene are associated with the highest metastatic risk, whereas gain-of-function mutations of SF3B1 and EIF1AX often confer a better prognosis. Expression of a cancer-testis antigen called PRAME (preferentially expressed antigen in melanoma) has been shown to increase metastatic risks in both low-risk and high-risk melanomas. New therapeutic approaches, including molecular therapies and nanoparticle phototherapy, are currently being investigated as alternative treatment modalities for uveal melanoma.

Safety and efficacy of posterior sub-Tenon's carboplatin injection versus intravitreal melphalan therapy in the management of retinoblastoma with secondary vitreous seeds

AIM

To evaluate the safety and efficacy of posterior sub-Tenon's carboplatin injection compared to intravitreal melphalan injection in the management of retinoblastoma (RB) with secondary vitreous seeds. The outcome measures were vitreous seeds regression, need for other treatment modalities to achieve ocular salvage and treatment side effects.

METHODS

A prospective interventional comparative nonrandomized study included RB eyes developed secondary vitreous seeds during the period of follow up. They subdivided into two groups: study group I where posterior sub-Tenon's carboplatin (20 mg/2 mL) was injected and study group II where intravitreal melphalan (20 µg /0.1 mL) was injected. The injections repeated every 2-4wk.

RESULTS

Thirty-three eyes were included in the study. Seventeen eyes (16 patients) in study group I and 16 eyes (16 patients) in study group II. Ten eyes (30.3%) were completely salvaged following local chemotherapies. Ocular salvage was 23.5% following posterior sub-Tenon's carboplatin injection versus 37.5% following intravitreal melphalan raised to 47.1% and 75% with addition of external beam radiotherapy (EBR) with no statistically significant difference between the study groups (P=0.16). A statistically significant correlation was found between ocular salvage rate and type of vitreous seeds either dust, spheres and clouds (r=0.42, P=0.015) and eyes harbor new solid tumor growth (r=0.35, P=0.045). The mean and median follow up periods following local chemotherapy injections were 2.0y in the study group I and 2.37y in the study group II. Few complications were reported: periorbital edema in all eyes and ocular motility disturbances in 13 eyes (76.5%) following posterior sub-Tenon's carboplatin injection. Vitreous hemorrhage developed in 2 eyes (12.5%) and localized retinopathy in 5 eyes (31.25%) following intravitreal melphalan.

CONCLUSION

Local chemotherapy for treatment of RB with secondary vitreous seeds is safe and can salvage 30.3% of eyes without EBR. There is a superiority of intravitreal melphalan in ocular salvage however, no statistically significant difference between both groups.

Hypoxia inhibits growth, proliferation, and increases response to chemotherapy in retinoblastoma cells

Retinoblastoma is a malignant tumor of the retina and the most frequent intraocular cancer in children. Low oxygen tension (hypoxia) is a common phenomenon in advanced retinoblastomas, but its biological effect on retinoblastoma growth is not clearly understood. Here we studied how hypoxia altered retinoblastoma gene expression and modulated growth and response to chemotherapy. The hypoxic marker lysyl oxidase (LOX) was expressed in 8 of 12 human retinoblastomas analyzed by immunohistochemistry, suggesting that a hypoxic microenvironment is present in up to two thirds of the cases. WERI Rb1 and Y79 retinoblastoma lines were exposed to 1% or 5% pO₂, cobalt chloride (CoCl₂), or to normoxia (21% pO₂) for up to 8 days. Both 1% and 5% pO₂ inhibited growth of both lines by more than 50%. Proliferation was reduced by 25-50% when retinoblastoma cells were exposed to 1% vs 21% pO₂, as determined by Ki67 assay. Surprisingly, Melphalan, Carboplatin, and Etoposide produced greater reduction in growth and survival of hypoxic cells than normoxic ones. Gene expression profile analysis of both lines, exposed for 48 h to 1%, 5%, or 21% pO₂, showed that glycolysis and glucose transport were the most up-regulated pathways, whereas oxidative phosphorylation was the most down-regulated pathway in hypoxia as compared to normoxia. These data support a role for hypoxia in suppressing growth, proliferation, and enhancing response of retinoblastoma cells to chemotherapy, possibly by impairing energy production through activation of glycolysis and inhibition of mitochondrial respiration. Targeting glucose metabolism or enhancing delivery of chemotherapeutic agents to hypoxic regions may improve treatment of advanced retinoblastomas.

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.

INTRAARTERIAL CHEMOTHERAPY FOR RETINOBLASTOMA IN A 2-MONTH-OLD INFANT

PURPOSE

Intraarterial chemotherapy for retinoblastoma is usually reserved for infants aged 3 months or older because of the intricacy of the newborn vascular anatomy making the procedure technically challenging. The authors report a successful case of intraarterial chemotherapy performed in a 2-month-old infant using a minimal exposure approach.

METHODS

Case report.

RESULTS

A 2-month-old infant presented with leukocoria and was subsequently diagnosed with an exophytic Group D retinoblastoma in the right eye. The infant received melphalan 3 mg delivered into the ostium of the ophthalmic artery of the right eye under fluoroscopic guidance. Examination under anesthesia a month later showed complete tumor regression to a calcified Type I scar. After a second cycle of intraarterial chemotherapy, no further treatment was necessary. There were no complications.

CONCLUSION

Intraarterial chemotherapy is generally used for retinoblastoma in infants aged 3 months or older. The patient was successfully catheterized and treated at 2 months of age, with complete tumor regression after a single chemotherapy dose. Thus, in expert hands, intraarterial chemotherapy can be considered in such young infants.

Retinoblastoma Control With Primary Intra-arterial Chemotherapy: Outcomes Before and During the Intravitreal Chemotherapy Era

PURPOSE

To compare outcomes of intra-arterial chemotherapy for retinoblastoma as primary therapy before (Era I) and during (Era II) the intravitreal chemotherapy era.

METHODS

In this retrospective interventional case series at a tertiary referral center, 66 eyes of 66 patients with untreated unilateral retinoblastoma were used. intraarterial chemotherapy into the ophthalmic artery under fluoroscopic guidance was performed using melphalan in every case, with additional topotecan as necessary. Intravitreal chemotherapy using melphalan and/or topotecan was employed as needed for active vitreous seeding. Globe salvage was measured based on the International Classification of Retinoblastoma (ICRB) during two eras.

RESULTS

The two eras encompassed 2008 to 2012 (intraarterial chemotherapy alone, Era I) and 2012 to 2015 (intraarterial chemotherapy plus intravitreal chemotherapy, Era II). Over this period, there were 66 patients with unilateral untreated retinoblastoma treated with primary intra-arterial chemotherapy. A comparison of features (Era I vs Era II) revealed no significant difference in mean patient age (24 vs 24 months), ICRB groups, mean largest tumor diameter (19 vs 17 mm), mean largest tumor thickness (10 vs 10 mm), vitreous seed presence (56% vs 59%), subretinal seed presence (67% vs 62%), retinal detachment (70% vs 66%), or vitreous hemorrhage (0% vs 5%). There was no significant difference in mean number of intra-arterial chemotherapy cycles (3 vs 3.1) or intraarterial chemotherapy dosages. Following therapy, there was a significant difference (Era I vs Era II) in the need for enucleation overall (44% vs 15%, P = .012), especially for group E eyes (75% vs 27%, P = .039). Four of the eyes that initiated therapy in Era I later required intravitreal chemotherapy during Era II. The enucleation rate was 0% for groups B and C in both eras and non-significant for group D (23% vs 13%). There were no patients with stroke, seizure, limb ischemia, extraocular tumor extension, secondary leukemia, metastasis, or death.

CONCLUSIONS

The current era of retinoblastoma management using intra-arterial chemotherapy plus additional intravitreal chemotherapy (as needed for vitreous seeding) has improved globe salvage in eyes with advanced retinoblastoma. [J Pediatr Ophthalmol Strabismus. 2016;53(5):275-284.].

A review of the literature for intra-arterial chemotherapy used to treat retinoblastoma

Retinoblastoma is a malignancy of the retina that usually presents before the age of 5 years. Sporadic retinoblastoma is most often unilateral and with no hereditary influence, whereas familial retinoblastoma presents unilaterally or bilaterally in conjunction with genetic inheritance. Several treatments have been attempted with the goals of saving the child's life, salvaging the eye, and preserving vision. Alternative methods including external beam radiation, systemic chemotherapy and focal therapies have been shown to be effective but carry a risk of enucleation and other complications proportional to the severity of the tumor. Selective intra-arterial chemotherapy for retinoblastoma began in 1988 in Japan and has emerged in the last 7 years in the United States as a feasible, effective and minimally invasive treatment option. We review the retinoblastoma treatment literature focusing on intra-arterial chemotherapy.

Secondary and tertiary intra-arterial chemotherapy for massive persistent or recurrent subretinal retinoblastoma seeds following previous chemotherapy exposure: long-term tumor control and globe salvage in 30 eyes

PURPOSE

To describe the results of intra-arterial chemotherapy (IAC) for control of persistent or recurrent subretinal seeds (SRS) following previous chemotherapy for retinoblastoma.

METHODS

We reviewed the medical records of patients with massive persistent or recurrent SRS after intravenous and/or intra-arterial chemotherapy and subsequently treated with superselective ophthalmic artery infusion of melphalan (3, 5, or 7.5 mg) and/or additional topotecan (1 mg) and/or carboplatin (20 or 30 mg) as necessary from January 2009 to March 2014. The main outcome measures were SRS control and globe salvage.

RESULTS

A total of 30 eyes of 29 patients were included. Mean patient age was 19 months (median, 14 months; range, 2-58 months). Previous treatments included intravenous chemotherapy (n = 28) and intra-arterial chemotherapy (n = 5). The SRS occupied a median of 6 clock hours. Retinal detachment was present in 5 eyes (17%). Each eye received a mean of 3 IAC sessions (median, 2; range, 1-7) on a monthly basis. After a mean follow-up of 24 months (median, 18; range, 1-71 months), 27 of eyes (90%) demonstrated complete SRS regression. Overall, globe salvage was achieved in 15 eyes (50%). Fifteen eyes were enucleated because of recurrent SRS (4 eyes), recurrent SRS and vitreous seeds (3 eyes), recurrent solid tumor (1 eye), and neovascular glaucoma from total retinal detachment and/or vitreous hemorrhage (7 eyes), none of which had active tumor.

CONCLUSIONS

IAC can be an effective second- or third-line therapy in the management of massive persistent or recurrent SRS from retinoblastoma following previous chemotherapy. All eyes in this study were all facing enucleation; lasting seed control was achieved in 70%.

Minimal exposure intra-arterial chemotherapy for children with retinoblastoma and 13q syndrome

Two infants with retinoblastoma and 13q syndrome with multiorgan system anomalies were treated with targeted intra-arterial chemotherapy (IAC) using one-to-three cycles of melphalan 5 mg to avoid systemic chemotherapeutic side effects. Both patients showed good response, with tumor control and no systemic chemotherapy side effects. Of the treatment modalities currently available, IAC may represent an optimal balance between tumor extermination and adverse drug reactions in this patient population with classically reduced multiorgan reserve.

Chemotherapy in Retinoblastoma: Current Approaches

Retinoblastoma (RB) is the most common childhood malignant intraocular tumor. Although enucleation and external beam radiotherapy have been historically used, today the most commonly used eye-sparing approach is chemotherapy. Chemotherapy can be used in both intraocular and extraocular RB cases. Chemotherapeutic agents may be applied in different ways, including systemic, subconjunctival, intra-arterial and intravitreal routes. The main purposes of application of systemic therapy are to reduce the tumor size for local treatment (chemoreduction), or to reduce the risk of metastasis after enucleation surgery (adjuvant therapy). Intra-arterial chemotherapy with the current name “super-selective intra-arterial infusion therapy” could be applied as primary therapy in tumors confined to the retina or as a secondary method in tumor recurrence. The most important advantage of intra-arterial therapy is the prevention of systemic chemotherapy complications. Intravitreal chemotherapy is administered in the presence of persistent or recurrent vitreous seeding. The term “extraocular RB” includes orbital invasion and metastatic disease. Current treatment for orbital invasion is neoadjuvant chemotherapy followed by surgical enucleation and adjuvant chemotherapy and radiotherapy after surgery. In metastatic disease, regional lymph node involvement, distant metastases, and/or central nervous system (CNS) involvement may occur. Among them, CNS involvement has the worst prognosis, remaining at almost 100% mortality. In metastatic disease, high-dose salvage chemotherapy and autologous hematopoietic stem cell rescue therapy are the possible treatment options; radiotherapy could also be added to the protocol according to the side of involvement.

Ocular dysmotility after intra-arterial chemotherapy for retinoblastoma

We report the case of a 15-month-old boy with retinoblastoma who developed exotropia secondary to a right medial rectus infarct after intra-arterial chemotherapy. He had unilateral sporadic group C tumor (International Classification of Retinoblastoma) and was treated with intra-arterial melphalan. One week after the first session of intra-ophthalmic arterial melphalan chemotherapy, he was noted to have orbital congestion, exotropia, and right adduction limitation. Magnetic resonance imaging was suggestive of a right medial rectus infarct. The tumor showed a good response to intra-arterial chemotherapy but the exotropia persisted.

Intra-Arterial Chemotherapy for Retinoblastoma: A Single-Center Experience

Background: Studies conducted in recent years have reported promising results regarding the treatment of retinoblastoma with the intra-arterial use of melphalan. In the present study, we intended to report the results of intra-arterial chemotherapy with melphalan (IACT) in the treatment of newly diagnosed or relapsed-refractory retinoblastoma patients at the Department of Pediatric Oncology of Hacettepe University, Ankara, Turkey. Materials and Methods: This was a retrospective study of patients with intraocular retinoblastoma who were treated with IACT from December 2011 to May 2014. A total of 56 eyes of 46 consecutive patients (30 males and 16 females) were included in the study. Forty-four eyes received systemic chemotherapy upon diagnosis (systemic chemotherapy group, SCG), and 12 eyes were those of newly diagnosed patients (primary intra-arterial melphalan group, PIAG). The choice of the IACT dose was based on age. Tumor control and globe salvage with IACT were analyzed. Complete blood counts were examined 7 days after the IACT for systemic toxicity. Ocular toxicities such as proptosis, eyelid edema, ocular motility, and retinal and optic atrophy were assessed by an ocular oncologist with regular ophthalmologic examinations. Results: Enucleation was avoided overall in 66% (37/56) of the eyes, including 75% (9/12) in the PIAG and 64% (28/44) in the SCG patients. The 1-year enucleation-free survival rate was 56.7% at a median follow-up time of 11.9 months (range 0.27-27.6). IACT was administered in a total of 124 cycles (ranging from 1 to 7 cycles, mean 2.3). The responses were as follows: regression of the retinal tumor in 27 eyes and improvements in vitreous seeding in 5 of 15 eyes. The further treatment requirements after IACT were as follows: enucleation in 19 eyes (10 with vitreous seeding), radiotherapy in 3 eyes, systemic chemotherapy in 1 eye, and local therapy in 1 eye. No severe systemic side effects occurred. Transient swelling of the eyelids (22 patients), conjunctival chemosis (12 patients), upper eyelid ptosis (5 patients), redness over the frontal area (3 patients), limitation of ocular motility (3 patients) and mild proptosis (1 patient) were detected. Retinal pigment epithelial alterations (30 patients) and optic atrophy (3 patients) were seen in the late follow-up. Conclusions: Globe salvage and avoidance of radiotherapy may be achieved by IACT with limited toxicity. This treatment is efficient, repeatable and safe.

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

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

Superselective intra-arterial melphalan therapy for newly diagnosed and refractory retinoblastoma: results from a single institution

Background:

Intra-arterial administration of melphalan chemotherapy has shown promise in the treatment of retinoblastoma. This report describes our results using superselective intra-arterial melphalan in patients with newly diagnosed retinoblastoma and those who were treated for progression after systemic chemotherapy.

Methods:

This is a retrospective review of all retinoblastoma patients treated with intra-arterial melphalan at the University of California, San Francisco from March 2010 to August 2012. Twenty eyes (16 patients) underwent 40 intra-arterial melphalan infusions, and dose was determined by age. Patients were treated at monthly intervals and received a range of 1–5 treatments. Response to therapy, toxicity, and procedural radiation exposure was assessed.

Results:

All patients are alive without metastatic disease at a median follow-up of 14.5 (1–29) months. Treatment with enucleation or external beam radiation was avoided in 11/20 eyes (55%) overall [6/12 (50%) in newly diagnosed eyes and 5/8 (63%) in refractory/relapsed eyes]. Response rates (per the International Classification of Retinoblastoma) were as follows: 6/7 (86%) in groups A–C and 5/13 (38%) in groups D and E. Nonhematologic and hematologic toxicities were minimal and comparable with those in previous reports. The mean procedural radiation dose was 20.2 ± 11.9 mGy per eye per procedure.

Conclusion:

Superselective intra-arterial melphalan therapy is effective for less advanced eyes but further modifications to therapy are required to improve results in eyes with advanced retinoblastoma.

A clinical update and radiologic review of pediatric orbital and ocular tumors

While pediatric orbital tumors are most often managed in tertiary care centers, clinicians should be aware of the signs of intraocular and orbital neoplasms. In the pediatric population, a delay in diagnosis of orbital and intraocular lesions, even if benign, can lead to vision loss and deformity. Intraocular lesions reviewed are retinoblastoma, medulloepithelioma, and retinal astrocytic hamartoma. Orbital neoplasms reviewed are rhabdomyosarcoma, neuroblastoma metastases, optic pathway glioma, plexiform neurofibroma, leukemia, lymphoprolipherative disease, orbital inflammatory syndrome, dermoid and epidermoid inclusion cysts, and Langerhans' cell histiocytosis. Vascular lesions reviewed are infantile hemangioma and venous lymphatic malformation. In conjunction with clinical examination, high-resolution ophthalmic imaging and radiologic imaging play an important role in making a diagnosis and differentiating between benign and likely malignant processes. The radiologic imaging characteristics of these lesions will be discussed to facilitate prompt diagnosis and treatment. The current treatment modalities and management of tumors will also be reviewed.

Update on Ophthalmic Oncology 2012: Advances in Retinoblastoma and Uveal Melanoma

PURPOSE

The purpose of this article was to review the major advances in both translational and clinical research in 2 diseases, retinoblastoma and uveal melanoma, from November 2011 through October 2012.

DESIGN

Literature Review.

METHODS

A MEDLINE search was performed using the search terms "retinoblastoma" and "uveal melanoma." All relevant articles were reviewed, and articles with the most clinical relevance were reported.

RESULTS

In retinoblastoma, new clinical data are emerging every year regarding the safety and efficacy of intra-arterial chemotherapy as well as other even newer modalities such as intravitreal chemotherapy. Globe salvage rates for eyes without vitreous seeding approach 100% and are increasing to 80% for those with seeds with new methods of treatment. In uveal melanoma, our understanding of the genetic pathways underlying this disease is improving each day and leading to the initiation of clinical trials for adjuvant therapy and metastatic disease.

CONCLUSIONS

Ocular oncology is a small but dynamic field in which our knowledge is increasing every day. Exciting data emerged in the fields of both retinoblastoma and uveal melanoma this year.

Retinoblastoma frontiers with intravenous, intra-arterial, periocular, and intravitreal chemotherapy

In this report, we explore retinoblastoma diagnostic accuracy and review chemotherapy alternatives for retinoblastoma using intravenous, intra-arterial, periocular, and intravitreal routes. A review of 2775 patients referred for management of retinoblastoma, disclosed 78% with confirmed retinoblastoma and 22% with simulating lesions, termed pseudoretinoblastomas. Children ≤2 years old showed leading pseudoretinoblastomas of persistent fetal vasculature, Coats disease, and vitreous haemorrhage, whereas those >5 years showed simulators of Coats, toxocariasis, and familial exudative vitreoretinopathy. The diagnosis of retinoblastoma should be established before planning therapeutic strategy. Chemotherapy strategy depends on tumour laterality and stage of disease. If bilateral retinoblastoma, intravenous chemotherapy (IVC) is important as first-line therapy for control of intraocular disease, prevention of metastasis, and reduction in prevalence of pinealoblastoma and long-term second malignant neoplasms. Bilateral groups D and E retinoblastoma receive additional subtenon's carboplatin boost for improved local control. If unilateral disease is present, then intra-arterial chemotherapy (IAC) is often considered. IAC can be salvage therapy following chemoreduction failure. Unilateral retinoblastoma of groups D and E are managed with enucleation or globe-conserving IVC and/or IAC. Intravitreal chemotherapy is cautiously reserved for recurrent vitreous seeds following other therapies. In conclusion, the strategy for retinoblastoma management with chemotherapy depends on tumour laterality and stage of disease. Bilateral retinoblastoma is most often managed with IVC and unilateral retinoblastoma with IAC, but if advanced stage, combination IVC plus IAC or enucleation.

Single-agent, minimal dose, minimal exposure intraarterial chemotherapy for retinoblastoma in a 4-month-old infant

PURPOSE

To document minimal dose and minimal exposure of chemotherapy for unilateral retinoblastoma.

METHODS

A 4-month-old infant developed leukocoria in the right eye and was found to have unilateral sporadic retinoblastoma.

RESULTS

The right eye was classified as Group D retinoblastoma, with a single large tumor, moderate subretinal seeding, and total retinal detachment. The retinoblastoma measured 20 mm in basal dimension and 13 mm in ultrasonographic thickness. Options of enucleation, intravenous chemotherapy, and intraarterial chemotherapy were offered, but the latter was chosen because of anticipated, rapid, and more complete response with intraarterial rather than intravenous chemotherapy. After using low dose (3 mg) of single-agent melphalan delivered over 30 minutes into the ostium of the ophthalmic artery of the 4-month-old infant, a complete response with Type 1 regression (complete calcification) of the mass and resolution of all subretinal fluid was found. A second similar dose was delivered to ensure remission of all seeds and tumor with stable findings. Further chemotherapy was stopped. On 6 months of follow-up, the child displayed complete tumor control with 2 cycles of lowest dose (3 mg) intraarterial melphalan. There were no complications.

CONCLUSION

In infants younger than 6 months, low dose of only 3-mg single-agent melphalan could be sufficient to control retinoblastoma with minimal exposure.

Validating a nonhuman primate model of super-selective intraophthalmic artery chemotherapy: comparing ophthalmic artery diameters

PURPOSE

Superselective intraophthalmic artery chemotherapy (SSIOAC) is being used for treatment of retinoblastoma; however, the hemodynamic consequences and toxicities are not fully known. We developed a nonhuman primate (NHP) model of SSIOAC and reported our clinical observations. For validation, we compared ophthalmic artery (OA) diameters between NHPs and children (<6 years).

METHODS

Endovascular cannulation of the right OA was performed three times each in six adult male Rhesus macaques. Angiographic OA images were obtained and measured, and postmortem OAs were histologically sectioned and measured. Retrospectively, computed tomography (CT) and magnetic resonance (MR) angiography images of the head in children and adolescents (as an adult reference) were used to measure the OA luminal diameter at its origin.

RESULTS

The median angiographic diameter of treated NHP OA origins (n = 6) was 1.06 mm (range 0.94-1.56). Histologic measurements (8 of 12 NHP OAs) gave a median diameter of 1.09 mm (range 0.95-1.41). In 98 children (from 169 consecutive CT and MR angiography studies; median age 1.01 years, range 0.01-5.74), 186 OAs were measurable at the origin (median luminal diameter 1.28 mm, range 0.82-2.00; P = 0.16 for the angiographic NHP diameters versus pediatric cohort). Angiographic measurements of 34 OAs (of 20 consecutive studies of adolescents; median age 16.55 years, range 14.40-18.18) gave a median luminal diameter of 1.45 mm (origin, range 1.13-1.66; P < 0.0001, adolescent versus pediatric).

CONCLUSIONS

Measurements of the OA luminal diameter at its origin were similar between our NHP and pediatric cohort, validating our NHP model for testing both the hemodynamic consequences and toxicities of SSIOAC.

Pearls and pitfalls of intraarterial chemotherapy for retinoblastoma

Retinoblastoma is a deadly eye cancer in children, leading to death in 50%-70% of children in undeveloped nations who are diagnosed with it. This malignancy is the most common intraocular tumor in childhood worldwide. The good prognosis in developed nations is related to early detection and advanced treatments. With the advent of intraarterial chemotherapy, neurosurgeons have taken a central role in the treatment of this pediatric condition. Intraarterial chemotherapy is a novel treatment for retinoblastoma whereby chemotherapeutic agents are precisely delivered into the ophthalmic artery, minimizing systemic toxicity. This procedure has shown impressive results and has allowed a dramatic decrease in the rate of enucleation (eye removal) in advanced and refractory retinoblastoma. Recent reports have raised some concerns about the risk of ocular vasculopathy, radiation-related toxicity, and the potential for metastatic disease after intraarterial chemotherapy. In the authors' experience of more than 3 years, tumor control is excellent with globe salvage at 67% and vascular events less than 5%, mostly related to improvement in technique. The role of this novel approach in the management of retinoblastoma has yet to be defined. As more centers are adopting the technique, the topic will decidedly become the focus of intensive future research. In this paper, the authors review and discuss current data regarding intraarterial chemotherapy for retinoblastoma.

Two-dose exposure of intra-arterial chemotherapy for group D retinoblastoma

The authors present a case of group D unilateral sporadic retinoblastoma treated with only two intra-arterial chemotherapy cycles using melphalan, which resulted in tumor regression, resolution of subretinal fluid, and, most importantly, salvage of the life, and the eye.