Chemoreduction and local ophthalmic therapy for intraocular retinoblastoma

MR Imaging of Adverse Effects and Ocular Growth Decline after Selective Intra-Arterial Chemotherapy for Retinoblastoma

This retrospective multicenter study examines therapy-induced orbital and ocular MRI findings in retinoblastoma patients following selective intra-arterial chemotherapy (SIAC) and quantifies the impact of SIAC on ocular and optic nerve growth. Patients were selected based on medical chart review, with inclusion criteria requiring the availability of posttreatment MR imaging encompassing T2-weighted and T1-weighted images (pre- and post-intravenous gadolinium administration). Qualitative features and quantitative measurements were independently scored by experienced radiologists, with deep learning segmentation aiding total eye volume assessment. Eyes were categorized into three groups: eyes receiving SIAC (Rb-SIAC), eyes treated with other eye-saving methods (Rb-control), and healthy eyes. The most prevalent adverse effects post-SIAC were inflammatory and vascular features, with therapy-induced contrast enhancement observed in the intraorbital optic nerve segment in 6% of patients. Quantitative analysis revealed significant growth arrest in Rb-SIAC eyes, particularly when treatment commenced ≤ 12 months of age. Optic nerve atrophy was a significant complication in Rb-SIAC eyes. In conclusion, this study highlights the vascular and inflammatory adverse effects observed post-SIAC in retinoblastoma patients and demonstrates a negative impact on eye and optic nerve growth, particularly in children treated ≤ 12 months of age, providing crucial insights for clinical management and future research.

Recent progress in retinoblastoma: Pathogenesis, presentation, diagnosis and management

Retinoblastoma, the primary ocular malignancy in pediatric patients, poses a substantial threat to mortality without prompt and effective management. The prognosis for survival and preservation of visual acuity hinges upon the disease severity at the time of initial diagnosis. Notably, retinoblastoma has played a crucial role in unraveling the genetic foundations of oncogenesis. The process of tumorigenesis commonly begins with the occurrence of biallelic mutation in the RB1 tumor suppressor gene, which is then followed by a cascade of genetic and epigenetic alterations that correspond to the clinical stage and pathological features of the tumor. The RB1 gene, recognized as a tumor suppressor, encodes the retinoblastoma protein, which plays a vital role in governing cellular replication through interactions with E2F transcription factors and chromatin remodeling proteins. The diagnosis and treatment of retinoblastoma necessitate consideration of numerous factors, including disease staging, germline mutation status, family psychosocial factors, and the resources available within the institution. This review has systematically compiled and categorized the latest developments in the diagnosis and treatment of retinoblastoma which enhanced the quality of care for this pediatric malignancy.

A multi-institutional feasibility study of intra-arterial chemotherapy in children with retinoblastoma. A Children's Oncology Group study (COG ARET12P1)

BACKGROUND

Intra-arterial chemotherapy (IA) as a treatment to salvage the eye with advanced retinoblastoma is increasingly utilized based on successes reported by institutions around the world mainly through retrospective studies.

OBJECTIVE

To study the feasibility of delivering melphalan directly into the ophthalmic artery in a multi-institutional prospective study in children with newly diagnosed unilateral group D retinoblastoma.

METHODS

The Children's Oncology Group (COG) initiated study ARET12P1 in 2014 and was open to nine institutions. Eligible patients older than six months of age were enrolled. The feasibility of delivering three injections of melphalan into the ophthalmic artery every 28 days was assessed.

RESULTS

Nine institutions participated in this trial. Fourteen patients were enrolled, two of whom were unevaluable for feasibility. Four patients experienced a feasibility failure. In two patients, the ophthalmic artery could not be accessed for the second IA injection, in one the artery could not be accessed for the first injection, and one patient experienced grade 4 hypotension during the procedure.

CONCLUSION

Delivery of prescribed therapy within the context of this study did not meet the feasibility goals of the study with only a 67% feasibility success rate. These results should caution centers that plan to initiate this treatment and suggest investment in training to achieve technical expertise or referral to centers with expertise.

Incidence and Risk Factors for Neutropenia After Intra-Arterial Chemotherapy for Retinoblastoma

Importance

Intra-arterial chemotherapy (IAC) has quickly gained popularity as a mainstay of treatment for retinoblastoma. Intra-arterial chemotherapy has been described as having several advantages over systemic chemotherapy, including reducing systemic toxicity and neutropenia; however, studies on the risk of neutropenia after IAC remain limited.

Objective

To estimate the incidence of neutropenia after IAC, as well as identify risk factors associated with the development of neutropenia.

Design, Setting, and Participants

This case series included pediatric patients with unilateral or bilateral retinoblastoma who were treated with IAC at a single quaternary care center from July 13, 2013, to January 6, 2023.

Exposure

All patients were treated with IAC and underwent multiple IAC cycles depending on treatment response. The primary chemotherapy agent used was melphalan, but topotecan or carboplatin could be used along with melphalan. Melphalan doses were kept to 0.4 mg/kg or less per cycle. After each IAC cycle, complete blood cell counts were obtained within 10 to 12 days and repeated until the absolute neutrophil count (ANC) was greater than or equal to 1000/μL.

Main Outcomes and Measures

The primary outcome was the minimum ANC after each IAC cycle. The secondary outcome was the development of severe (grade 3 or 4) neutropenia (ANC <1000/μL). Regression analyses were used to identify associations between variables and outcomes. Receiver operating characteristic curves were used to calculate threshold dose for each chemotherapy agent potentially associated with the development of severe neutropenia.

Results

A total of 64 eyes of 49 patients (mean [SD] age, 1.7 [1.2] years; 25 females [51.0%]) with retinoblastoma were treated with 171 cycles of IAC. The mean (SD) nadir ANC was 1325.3 (890.7)/μL and occurred a median (IQR) of 10 (10-14) days (range, 6-28 days) after IAC administration. The frequency distribution of post-IAC neutropenia grades 0, 1, 2, 3, 4, and missing was 31 (18.1% of cycles), 25 (14.6%), 40 (23.4%), 37 (21.6%), 26 (15.2%), and 12 (7.0%), respectively. Factors weakly correlated with a lower ANC were higher melphalan dose (β = -2356 [95% CI, -4120.6 to -611.2]; adjusted R2 = 0.251; P = .01) and higher topotecan dose (β = -4056 [95% CI, -7003.6 to -1344.5]; adjusted R2 = 0.251; P = .006).

Conclusions and Relevance

In this case series of patients with retinoblastoma, the incidence of severe neutropenia after IAC was nearly 40%, which is higher than previously reported. Extended laboratory monitoring may aid in capturing previously overlooked cases of neutropenia. Topotecan may be associated with the development of neutropenia; limiting topotecan doses, especially in the setting of a high melphalan dose, may be beneficial in reducing the risk of neutropenia.

A comparison of high risk pathological features between primary and secondary enucleation for retinoblastoma

AIM

To compare the risk and pattern of High-Risk Pathologic Features (HRPF) in retinoblastoma between primary and secondary enucleation.

METHODS

A retrospective analysis of 121 eyes from 118 patients who underwent enucleation at the King Hussein Cancer Center (KHCC) Amman, Jordan, between November 2009 and January 2020. Demographic information, tumor stage, time from diagnosis-to-enucleation, results of pathology, metastasis, and mortality were retrieved.

RESULTS

Patients in the secondary group (49/121 eyes, 40%) were considerably younger at diagnosis (p = 0.0014), had bilateral disease (p = 0.0001), and had less-progressed disease at presentation (p = 0.016) compared to the primary enucleation. Primarily enucleated eyes were more-likely to have massive choroidal invasion (p = 0.0315) and post-laminar optic nerve invasion (p = 0.027), in spite of the finding that the overall prevalence of HRPF was similar between the two groups (35.5 percent vs. 37.5 percent; p = 0.585). The likelihood of anterior chamber invasion, was considerably higher in secondary enucleated eyes (p = 0.013). We evaluated primary and secondary enucleation for each subgroup (D and E) of the International Intraocular Retinoblastoma Classification (IIRC) and found the prevalence of HRPF was comparable (p = 0.58, 1.0, respectively). The difference in time between diagnosis-to-enucleation in secondary enucleation did not predict HRPF (p = 0.50). There was no discernible difference between primary and secondary enucleated eyes in terms of metastasis or survival (p = 0.156 and 0.44, respectively).

CONCLUSION

Systemic chemotherapy has the ability to reduce the extent of tumor expansion that has been pathologically identified. Primary and secondary enucleated eyes are comparable in low metastatic risk only when strict examination and management guidelines are followed.

Signaling pathways driving ocular malignancies and their targeting by bioactive phytochemicals

Ocular cancers represent a rare pathology. The American Cancer Society estimates that 3,360 cases of ocular cancer occur annually in the United States. The major types of cancers of the eye include ocular melanoma (also known as uveal melanoma), ocular lymphoma, retinoblastoma, and squamous cell carcinoma. While uveal melanoma is one of the primary intraocular cancers with the highest occurrence in adults, retinoblastoma remains the most common primary intraocular cancer in children, and squamous cell carcinoma presents as the most common conjunctival cancer. The pathophysiology of these diseases involves specific cell signaling pathways. Oncogene mutations, tumor suppressor mutations, chromosome deletions/translocations and altered proteins are all described as causal events in developing ocular cancer. Without proper identification and treatment of these cancers, vision loss, cancer spread, and even death can occur. The current treatments for these cancers involve enucleation, radiation, excision, laser treatment, cryotherapy, immunotherapy, and chemotherapy. These treatments present a significant burden to the patient that includes a possible loss of vision and a myriad of side effects. Therefore, alternatives to traditional therapy are urgently needed. Intercepting the signaling pathways for these cancers with the use of naturally occurring phytochemicals could be a way to relieve both cancer burden and perhaps even prevent cancer occurrence. This research aims to present a comprehensive review of the signaling pathways involved in various ocular cancers, discuss current therapeutic options, and examine the potential of bioactive phytocompounds in the prevention and targeted treatment of ocular neoplasms. The current limitations, challenges, pitfalls, and future research directions are also discussed.

Highly Efficient Photodynamic Therapy with Mitochondria-Targeting Aggregation-Induced Emission Photosensitizer for Retinoblastoma

Retinoblastoma (RB) is an aggressive eye cancer in infancy and childhood, lethal by metastasis if left untreated. Currently, the survival rate and the chance of saving vision depend on the severity of the disease. In this work, a highly efficient photodynamic ophthalmic therapy for RB is reported by employing an isoquinolinium-based aggregation-induced-emission (AIE) photosensitizer (PS) TPE-IQ-2O for photodynamic inactivation (PDI). TPE-IQ-2O is an efficient mitochondria-targeting photosensitizer as an efficient guided photodynamic therapy (PDT) agent against cancer cells. Maximizing cancer-selectively damage to tumors with minimized side effects on normal tissue is essential for effective anticancer PDT and provides long-lasting protection against metastasis. In addition, TPE-IQ-2O can effectively reduce the degree of tissue inflammation by inhibiting the expression of related inflammatory factors. TPE-IQ-2O also exhibits excellent biocompatibility with a neglectable hemolysis effect on mouse red blood cells and almost no killing effect on mammalian cells, which enables its potential applications in the treatment of RB.

Stereotactic Gamma Knife® Radiosurgery of Intraocular Retinoblastoma: Six-Year Experience

Background

External beam radiotherapy for resistant retinoblastoma is now seen as a last resort to saving the eye because of the risk of severe side effects: secondary cancers and cosmetic problems of orbital bone growth retardation. To reduce such complications, treatment modalities have shifted towards new radiation therapy techniques. No information on single fraction Gamma Knife® radiosurgery (GKRS) for intraocular retinoblastoma exists.

Materials and methods

Eighteen children (19 eyes) with retinoblastoma were treated with GKRS. The mean age at the time of treatment was 35 months (from 12 to 114 months). Before GKRS, all routes of chemotherapy delivery were held in all cases. The eligibility criteria for GKRS were retinoblastomas not amenable either to systemic or local chemotherapy and local ophthalmological treatment, retinoblastomas too large for conventional local methods, and inability to perform intraarterial chemotherapy. Conventional external beam radiotherapy was excluded in the presented cases, given the possible complications mentioned above. In every case, eye removal was suggested to the child's parents, but they flatly refused. GKRS was proposed as the last chance to save the eye (in four cases, it was performed on the only eye). The median prescribed dose was 22 Gy (interquartile range [IQR]: 18-35 Gy), and the median prescribed isodose was 50% (IQR: 36-90%).

Results

Local control was achieved in 79% of cases (complete tumor regression in 69%, incomplete regression in 10%). Two eyes (10.5%) could not be preserved and had to be enucleated due to the tumor recurrence. Two eyes (10.5%) developed secondary complications (total vitreous hemorrhage, retinal detachment, and iris neovascularization), making adequate tumor control nearly impossible. Overall, 15 eyes (79%) were preserved, and four eyes (21%) were enucleated after GKRS with no signs of tumor recurrence and metastasis in the mean follow-up of 41 months. No acute radiation side effects occurred in any patient after GKRS. Ten children (10 eyes, 53%) were diagnosed with vitreous hemorrhage from mild to severe. Three eyes presented with optic neuropathy one year after GKRS, and four eyes developed retinopathy. Radiation-induced cataract occurred in two eyes. There were no cases of secondary glaucoma or keratopathy in our study. All patients and eyes treated by GKRS were stable within 41 months (from seven to 74 months).

Conclusions

Single fraction Gamma Knife® radiosurgery may be a reasonable salvage treatment for resistant and recurrent retinoblastoma as an alternative approach to enucleation in selected cases. GKRS should be considered in retinoblastoma management.

Intra-Arterial Chemotherapy as Primary Treatment for Advanced Unilateral Retinoblastoma in China

Purpose

This study aimed to evaluate the efficacy and complications of intra-arterial chemotherapy (IAC) as a primary treatment for advanced unilateral retinoblastoma in Chinese patients.

Methods

This study was a retrospective review of patients with advanced unilateral retinoblastoma treated with IAC as the primary treatment. The IAC procedures were performed using a balloon-assisted technique. The clinical status and treatment complications were recorded at each visit. Kaplan–Meier analysis was performed to estimate recurrence-free survival and ocular survival.

Results

In total, 116 eyes of 116 patients with advanced unilateral retinoblastoma were enrolled, including 66 eyes (57%) in group D and 50 eyes (43%) in group E. All treated eyes received a mean of 3 cycles of IAC (range, 3–5), and 66% of the eyes were combined with local consolidation therapy. The median follow-up time was 39 months (range, 22–57 months). The 3-year recurrence-free survival and ocular survival rates were 68.8% (95% CI, 59.2–76.6%) and 88.5% (95% CI, 80.9–93.2%), respectively. Moreover, the 3-year ocular survival rate in group D was significantly higher than that in group E (96.9%, 76.3%; P < 0.01). The common ocular complication was vitreous hemorrhage (19.8%). No deaths or severe systemic complications occurred.

Conclusion

Primary intra-arterial chemotherapy is effective for the treatment of advanced unilateral retinoblastoma, especially in group D, with acceptable toxicity.

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.

Case Report: Phototherapeutic Keratectomy for Band Keratopathy Secondary to Chemo-Laser-Cryotherapy for Retinoblastoma

Purpose: To report the clinical outcomes of phototherapeutic keratectomy (PTK) for pediatric band keratopathy after treatment for retinoblastoma.

Methods: A 5-year-old boy presented with a 2-year history of poor visual acuity and a horizontal gray-white band across the central cornea in the right eye. He was diagnosed with band keratopathy after chemo-laser-cryotherapy for retinoblastoma. The band keratopathy was treated via PTK using the Mel-90 excimer laser with an optical treatment zone of 7.0 mm and ablation depth of 120 μm. The patient was followed at 1 week and 3 months postoperatively.

Results: Surgery and postoperative follow-up were uneventful. At the 3-month follow-up, the uncorrected distant visual acuity of the right eye improved to 20/125, and the corrected distance visual acuity improved to 20/70 with a refraction of +10.00 D/−2.50 DC × 15. The clarity of the ablated area was evidently improved. The central corneal thickness decreases from 612 to 584 μm. The optical coherence tomography showed the thin band of hyperreflectivity in the ablated area disappeared, corneal transparency improved and the corneal surface smoothened.

Conclusions: PTK is a safe and effective procedure to treat band keratopathy following treatment of retinoblastoma in children. Early intervention can reduce the risk of developing deprivation amblyopia.

Developmental Delay and School Performance Among Retinoblastoma Survivors: Development/school morbidity among retinoblastoma survivors

PURPOSE

The purpose of this study was to describe the academic performance of childhood retinoblastoma (RB) survivors.

DESIGN

Retrospective cohort study.

METHODS

Retrospective chart review of children followed in a survivorship clinic.

RESULTS

A total of 73 patients with RB (median age at diagnosis: 9.97 months; range: 0.29-65.1) were followed for a median of 6.4 years (0.2-1.76). A total of 48 patients (65.8%) had unilateral RB; 43 patients (63.0%) received systemic chemotherapy; and 57 patients (78.1%) underwent enucleation. At last follow-up, 5 children (6.8%) had bilateral visual acuity (VA) <20/70. Seventeen subjects (23.3%) reported school difficulties, and 10 subjects (13.7%) had an individualized education program (IEP). Multivariate analysis revealed that a history of receiving chemotherapy" Multivariate analysis revealed that a history of receiving chemotherapy was associated with self-reported school difficulties (odds ratio [CI]: 5.44; 95% confidence interval [CI]: 1.36-21.69; P = .016), and undergoing an IEP (OR: 11.47; 95% CI: 1.34-98.16; P = .03). The degree of visual impairment and history of enucleation did not influence the risk of self-reported school difficulties or the implementation of an IEP. Among unilateral RB patients, chemotherapy was an independent risk factor for self-reported school difficulties (OR: 12.8; 95% CI: 1.45-113; P = .009) and implementation of an IEP (OR: 15.2; 95% CI: 0.78-292; P = .02).

CONCLUSIONS

Academic difficulties in childhood RB survivors are associated with chemotherapy treatment, a risk factor independent of VA.

The Predictive Value of the Eighth Edition of the Clinical TNM Staging System for the Likelihood of Eye Salvage for Intraocular Retinoblastoma by Systemic Chemotherapy and Focal Therapy

BACKGROUND

The American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) cTNM staging is emerging as a universal staging for all cancers, including retinoblastoma.

METHODS

Here we evaluated the predictive value of the eighth edition AJCC/UICC cTNM staging in comparison with the International Intraocular Retinoblastoma Classification for eye globe salvage by primary systemic chemotherapy and focal therapy (CRD) using logistic regression model for the probability of treatment failure.

RESULTS

The eye salvage rate for 565 treated eyes was 95% (n=139/147) for T1 tumors (98% for T1a and 93% for T1b), 56% (n=230/410) for T2 (81% for T2a and 53% for T2b), and 0% for T3 tumors, and was 98%, 93%, 76%, and 44% for group A, B, C, and D tumors, respectively. As estimated by odds ratios, T2 were 13.6-fold more likely to fail treatment than T1, and T1b, T2a, and T2b were 2.8-, 9.4-, and 35.1-fold more likely to fail treatment than T1a, respectively. Group B, C, and D tumors were 2.8-, 12.7-, and 50.1-fold more likely to fail treatment than group A tumors, respectively. Eye salvage rate was 62% for eyes with focal seeds (3 mm close to the tumor), and 42% for eyes with diffuse seeds (clouds more than 3 mm from tumor edge) (P<0.0001).

CONCLUSION

Both, the eighth edition cTNM classification and the International Intraocular Retinoblastoma Classification systems, can effectively predict eye salvage rates for retinoblastoma by CRD. Eyes with higher cT stages are more likely to experience treatment failure. Because the cT2b group is very heterogeneous, our findings suggest further division of this group based on the severity of vitreous/subretinal seeds, this should be revised in the next edition of cTNM system.

Long non-coding RNA XIST promotes retinoblastoma cell proliferation, migration, and invasion by modulating microRNA-191-5p/brain derived neurotrophic factor

Long non-coding RNA (lncRNA) X–inactive specific transcript (XIST) is oncogenic in multiple cancers. Herein, the present study is aimed at delving into how XIST functions in retinoblastoma (RB) and investigating its underlying mechanism. In this study, XIST, miR-191-5p, BDNF mRNA, and BDNF expression levels in RB tissues or cell lines were examined by quantitative real-time polymerase chain reaction (qRT-PCR) or Western blot. The models of gain-of-function and loss-of-function were established by the transfection of pcDNA3.1-XIST, XIST siRNA, and miR-191-5p mimics and inhibitors into SO-Rb50 and Y79 cells, respectively. RB cell proliferation, migration, invasion, and apoptosis were detected employing cell counting kit-8 (CCK-8), Transwell, and terminal deoxynucleotidyl transferased UTP nick end labeling (TUNEL) assays. The regulatory relationships among XIST, miR-191-5p, and BDNF were affirmed utilizing bioinformatics analysis, luciferase reporter assay, qRT-PCR, as well as Western blot. We reported that, XIST expression was markedly elevated in RB tissue and RB cells. XIST overexpression accelerated RB cell proliferation, migration, and invasion, and attenuated RB cell apoptosis but miR-191-5p exerted the opposite effects. Besides, BDNF expression was inhibited by miR-191-5p in both mRNA and protein levels. XIST indirectly improved BDNF expression by repressing miR-191-5p expression as a competitive endogenous RNA. In conclusion, XIST expression is abnormally elevated in RB tissues and XIST can modulate proliferation, migration, invasion, and apoptosis of RB cells by regulating miR-191-5p/BDNF axis.

Rare tumors: Retinoblastoma, nasopharyngeal cancer, and adrenocorticoid tumors

The role of surgery, chemotherapy, and radiation therapy for retinoblastoma has evolved considerably over the years with the efficacy of intraarterial chemotherapy and the high incidence of secondary malignant neoplasms following radiation therapy. The use of spot scanning intensity-modulated proton therapy may reduce the risk of secondary malignancies. For pediatric nasopharyngeal carcinoma, the current standard of care is induction chemotherapy followed by chemoradiation therapy. For adrenocortical carcinoma, the mainstay of treatment is surgery and chemotherapy. The role of radiation therapy remains to be defined.

Response criteria for intraocular retinoblastoma: RB-RECIST

Standardized guidelines for assessing tumor response to therapy are essential for designing and conducting clinical trials. The Response Evaluation Criteria In Solid Tumors (RECIST) provide radiological standards for assessment of solid tumors. However, no such guidelines exist for the evaluation of intraocular cancer, and ocular oncology clinical trials have largely relied on indirect measures of therapeutic response-such as progression-free survival-to evaluate the efficacy of treatment agents. Herein, we propose specific criteria for evaluating treatment response of retinoblastoma, the most common pediatric intraocular cancer, and emphasize a multimodal imaging approach for comprehensive assessment of retinoblastoma tumors in clinical trials.

Feasibility of Proton Beam Therapy as a Rescue Therapy in Heavily Pre-Treated Retinoblastoma Eyes

Simple Summary

A variety of therapies are available for the treatment of retinoblastomas. Nevertheless, despite exhaustion of all therapeutic methods, refractory or recurrent courses of the disease occur. In eyes with a function worthy of preservation radiation therapy may become unavoidable. Proton beam therapy, compared to conventional photon-based radiotherapy, is a highly conformal form of radiation therapy with a high biological effectiveness with a simultaneously reduced probability of radiation-related side-effects and induction of secondary primary malignancies. The aim of our retrospective study was to evaluate the efficacy of proton beam therapy as rescue therapy in 15 heavily pretreated retinoblastoma eyes. In our retrospective series of a highly negatively selected patient population, we were able to preserve 60% of the eyes with a manageable side effect profile. A cataract, as the most common long-term complication, was evident in 44.4% of the preserved eyes. There was no in-field second tumor manifestation during follow-up, therefore the preliminary data of this study and series published by others suggest that the risk is significantly lower after proton beam therapy compared to conventional external beam radiation therapy using photons.

Abstract

Despite the increased risk of subsequent primary tumors (SPTs) external beam radiation (EBRT) may be the only therapeutic option to preserve a retinoblastoma eye. Due to their physical properties, proton beam therapy (PBT) offers the possibility to use the effectiveness of EBRT in tumor treatment and to decisively reduce the treatment-related morbidity. We report our experiences of PBT as rescue therapy in a retrospectively studied cohort of 15 advanced retinoblastoma eyes as final option for eye-preserving therapy. The average age at the initiation of PBT was 35 (14–97) months, mean follow-up was 22 (2–46) months. Prior to PBT, all eyes were treated with systemic chemotherapy and a mean number of 7.1 additional treatments. Indication for PBT was non-feasibility of intra-arterial chemotherapy (IAC) in 10 eyes, tumor recurrence after IAC in another 3 eyes and diffuse infiltrating retinoblastoma in 2 eyes. Six eyes (40%) were enucleated after a mean time interval of 4.8 (1–8) months. Cataract formation was the most common complication affecting 44.4% of the preserved eyes, yet 77.8% achieved a visual acuity of >20/200. Two of the 15 children treated developed metastatic disease during follow-up, resulting in a 13.3% metastasis rate. PBT is a useful treatment modality as a rescue therapy in retinoblastoma eyes with an eye-preserving rate of 60%. As patients are at lifetime risk of SPTs consistent monitoring is mandatory.

Dosimetric comparison of different radiotherapy techniques for the treatment of Retinoblastoma

Aim:

This study aims to compare the dosimetric parameters among four different external beam radiotherapy techniques used for the treatment of retinoblastoma.

Materials and methods:

Computed tomography (CT) sets of five retinoblastoma patients who required radiotherapy to one globe were included. Four different plans were generated for each patient using three dimensional conformal radiotherapy (3DCRT), intensity modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and VMAT using flattening filter free (VMAT-FFF) beam techniques. Plans were compared for target coverage and organs at risk (OARs) sparing.

Results:

The target coverage of planning target volume (PTV) for all the four modalities were clinically acceptable with a V95 of 95 ± 0%, 97·6 ± 1·87%, 99·3 ± 0·5% and 99·17 ± 0·45% for 3DCRT, IMRT, VMAT and VMAT-FFF respectively. The VMAT and IMRT plans had better target coverage than the 3DCRT plans (p = 0·001 and p = 0·07 respectively). IMRT and VMAT plans were also found superior to 3DCRT plans in terms of OAR sparing like brainstem, optic chiasm, brain (p < 0·05). VMAT delivered significantly lower dose to the brainstem and contralateral optic nerve in comparison to IMRT. Use of VMAT-FFF beams did not show any benefit over VMAT in target coverage and OAR sparing.

Conclusion:

VMAT should be preferred over 3DCRT and IMRT for treatment of retinoblastoma owing to better target coverage and less dose to most of the OARs. However, IMRT and VMAT should be used with caution because of the increased low dose volumes to the OARs like contralateral lens and eyeball.

Modern treatment of retinoblastoma: A 2020 review

Retinoblastoma management remains complex, requiring individualized treatment based on International Classification of Retinoblastoma (ICRB) staging, germline mutation status, family psychosocial factors and cultural beliefs, and available institutional resources. For this 2020 retinoblastoma review, PubMed was searched for articles dated as early as 1931, with an emphasis on articles from 1990 to the present day, using keywords of retinoblastoma, chemotherapy, intravenous chemotherapy, chemoreduction, intra-arterial chemotherapy, ophthalmic artery chemosurgery, intravitreal chemotherapy, intracameral chemotherapy, cryotherapy, transpupillary thermotherapy, laser, radiation, external beam radiotherapy, plaque radiotherapy, brachytherapy, and enucleation. We discuss current treatment modalities as used in the year 2020, including intravenous chemotherapy (IVC), intra-arterial chemotherapy (IAC), intravitreal chemotherapy (IvitC), intracameral chemotherapy (IcamC), consolidation therapies (cryotherapy and transpupillary thermotherapy [TTT]), radiation-based therapies (external beam radiotherapy [EBRT] and plaque radiotherapy), and enucleation. Additionally, we present a consensus treatment algorithm based on the agreement of three North American retinoblastoma treatment centers, and encourage further collaboration amongst the world's most expert retinoblastoma treatment centers in order to develop consensus management plans and continue advancement in the identification and treatment of this childhood cancer.

A single-arm study of systemic and sub-Tenon chemotherapy for Groups C and D intraocular retinoblastoma: A Children's Oncology Group study (ARET 0231)

BACKGROUND

Eyes with Group D intraocular retinoblastoma have low salvage rates. A pilot study showed safety and efficacy of sub-Tenon's fascia carboplatin with systemic chemotherapy supporting further study.

METHODS

Children with newly diagnosed bilateral intraocular retinoblastoma with at least one remaining Group C or D eye were treated with six courses of carboplatin/etoposide/vincristine (CEV) with sub-Tenon's fascia carboplatin for Group C/D eyes during courses 2-4. Local ophthalmic therapy started at course 3. The primary study objective was to determine the 1-year failure rate of Group D eyes.

RESULTS

The study closed prematurely due to poor accrual and 22 of 30 patients were evaluable for failure rate, contributing 25 Group D and four Group C eyes. Among the 25 Group D eyes, there were 13 failures within the first year of study enrollment including eight needing external beam radiotherapy (EBR) and five needing enucleation, resulting in 1-year failure rate of 52%. The failure rate was significantly lower than the historical rate of 70% (P = .039). The 1-year eye preservation rate for Group D eyes was 80% (20/25). One-year failure rate for Group C eyes was 25% (1/4); 1-year preservation rate was 100% without need for EBR. Systemic toxicity included Grade 3 hearing loss in two subjects, infections, neutropenia, and thrombocytopenia. Ocular toxicities included periorbital fat atrophy (13/29 = 45% eyes), optic nerve atrophy (1/29 = 3% eyes), and restrictive fibrosis (1/29 = 3% eyes).

CONCLUSIONS

Sub-Tenon's fascia carboplatin plus CEV was partially effective in Group D intraocular retinoblastoma but had unacceptable ocular toxicities.

Expression Changes and Impact of the Extracellular Matrix on Etoposide Resistant Human Retinoblastoma Cell Lines

Retinoblastoma (RB) represents the most common malignant childhood eye tumor worldwide. Several studies indicate that the extracellular matrix (ECM) plays a crucial role in tumor growth and metastasis. Moreover, recent studies indicate that the ECM composition might influence the development of resistance to chemotherapy drugs. The objective of this study was to evaluate possible expression differences in the ECM compartment of the parental human cell lines WERI-RB1 (retinoblastoma 1) and Y79 and their Etoposide resistant subclones via polymerase chain reaction (PCR). Western blot analyses were performed to analyze protein levels. To explore the influence of ECM molecules on RB cell proliferation, death, and cluster formation, WERI-RB1 and resistant WERI-ETOR cells were cultivated on Fibronectin, Laminin, Tenascin-C, and Collagen IV and analyzed via time-lapse video microscopy as well as immunocytochemistry. We revealed a significantly reduced mRNA expression of the proteoglycans Brevican, Neurocan, and Versican in resistant WERI-ETOR compared to sensitive WERI-RB1 cells. Also, for the glycoproteins α1-Laminin, Fibronectin, Tenascin-C, and Tenascin-R as well as Collagen IV, reduced expression levels were observed in WERI-ETOR. Furthermore, a downregulation was detected for the matrix metalloproteinases MMP2, MMP7, MMP9, the tissue-inhibitor of metalloproteinase TIMP2, the Integrin receptor subunits ITGA4, ITGA5 and ITGB1, and all receptor protein tyrosine phosphatase β/ζ isoforms. Downregulation of Brevican, Collagen IV, Tenascin-R, MMP2, TIMP2, and ITGA5 was also verified in Etoposide resistant Y79 cells compared to sensitive ones. Protein levels of Tenascin-C and MMP-2 were comparable in both WERI cell lines. Interestingly, Fibronectin displayed an apoptosis-inducing effect on WERI-RB1 cells, whereas an anti-apoptotic influence was observed for Tenascin-C. Conversely, proliferation of WERI-ETOR cells was enhanced on Tenascin-C, while an anti-proliferative effect was observed on Fibronectin. In WERI-ETOR, cluster formation was decreased on the substrates Collagen IV, Fibronectin, and Tenascin-C. Collectively, we noted a different ECM mRNA expression and behavior of Etoposide resistant compared to sensitive RB cells. These findings may indicate a key role of ECM components in chemotherapy resistance formation of RB.

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.

Feasibility and results of an intraarterial chemotherapy program for the conservative treatment of retinoblastoma in Argentina

BACKGROUND

The feasibility and results of intraarterial chemotherapy, also termed ophthalmic artery chemosurgery (OAC), for retinoblastoma in less developed countries have seldom been reported.

PROCEDURE

A retrospective evaluation of a program of OAC in Argentina from 2010 to 2015.

RESULTS

Ninety-seven eyes from 81 patients (61 bilateral) were analyzed. In 35 eyes, OAC was given as primary therapy and in 62 it was used for the treatment of tumors with partial response or those relapsing after systemic chemoreduction with focal therapy or external-beam radiotherapy. Twenty-two primarily treated eyes had group D and 13 groups B/C. A total of 400 procedures were carried out. Chemotherapy used included combinations of melphalan, carboplatin, and topotecan. There was no mortality associated with OAC. Toxicity included fever and neutropenia in five (1.25%), hypotension and bradycardia during anesthesia in two and femoral thrombosis in one, eyelid edema in nine, and neutropenia or thrombocytopenia in 28 cycles. With a median follow-up of 48.7 months (range 12-79), the 3-year probability of event-free survival (pEFS) (enucleation and/or radiotherapy were considered events) was comparable for patients who received first-line therapy and those treated at relapse (0.65 vs. 0.63, P = 0.5). In the former, the pEFS was 0.91 and 0.43 for groups B/C and D, respectively (P = 0.01). Two patients died of extraocular dissemination after refusal of enucleation.

CONCLUSIONS

OAC was feasible with low toxicity. pEFS improved in all groups compared to the previous experience with systemic chemotherapy reducing the use of radiotherapy. The overall mortality associated with OAC is comparable to our previous experience with systemic chemoreduction.

MicroRNA‑874 prohibits the proliferation and invasion of retinoblastoma cells by directly targeting metadherin

MicroRNAs (miRNAs/miRs) serve important roles in regulating gene expression by directly binding to the 3'‑untranslated regions of target genes. Multiple miRNAs are dysregulated in retinoblastoma (RB) and their dysregulation is closely related to RB malignancy. Therefore, exploring the detailed roles of miRNAs in RB is valuable to facilitate the development of effective therapeutic targets for patients with this disease. miRNA‑874‑3p (miR‑874) has been recently reported to be downregulated in several types of human cancer and serves an essential role in cancer progression. However, the expression pattern and detailed roles of miR‑874 in RB, as well as the underlying molecular mechanisms in RB, have not been clearly elucidated. Therefore, this study detected miR‑874 expression in RB tissues and cell lines. The biological roles of miR‑874 in RB were determined and the underlying mechanisms of its actions in RB cells were also examined. This study revealed that miR‑874 expression was aberrantly underexpressed in RB tissues and cell lines. However, returning miR‑874 expression restricted the proliferative and invasive abilities of RB cells. In terms of the underlying mechanism, metadherin (MTDH) was validated as a direct target gene of miR‑874 in RB cells. MTDH inhibition could imitate the inhibitory roles of miR‑874 overexpression in RB cells. Furthermore, forced MTDH expression partially reversed the suppressive effects of miR‑874 on RB cells. In conclusion, this study revealed that miR‑874 may inhibit RB progression by directly targeting MTDH. Restoration of miR‑874 expression may be a novel strategy for preventing the rapid growth and metastasis of RB cells.

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.

Intravitreal chemotherapy in retinoblastoma: expanded use beyond intravitreal seeds

BACKGROUND/AIMS

Ophthalmic artery chemosurgery (OAC) has changed the face of retinoblastoma treatment and led to a higher rate of globe salvage. The introduction of intravitreal chemotherapy (IVitC) has further enhanced globe salvage with increased success in treatment of intravitreal seeds. Our group has seen success at treating non-vitreous disease that is refractory to OAC using IVitC. This study was undertaken to quantify and report on this success.

METHODS

A retrospective review was used to identify patients treated with IVitC for indications other than vitreous seeds from two centres. The indication, prior and concurrent treatment, response time and duration of treatment were documented. Kaplan-Meier estimates were used to evaluate ocular and recurrence-free survival. Ocular toxicity was evaluated using the 30 Hz flicker electroretinogram (ERG). Continuous and categorical variables were compared with Student's t-test and χ² test, respectively.

RESULTS

Fifty-six eyes from 52 retinoblastoma patients were identified. There were no disease-related or treatment-related deaths. One patient developed a second primary malignancy (pinealoblastoma) and subsequent leptomeningeal spread. Ninety-eight per cent of the eyes showed clinical regression. Recurrence was seen in 14.3%. Of the recurrences, five occurred in retinal tumours and three in subretinal seeds. The Kaplan-Meier estimated risk of recurrence in all patients treated was 83.5% (95% CI 7.9 to 14.1) at 10 months. The mean change in ERG over treatment course was -17.7 μV.

CONCLUSIONS

Intravitreal chemotherapy is successful for the treatment of subretinal seeds and recurrent retinal tumours and could be considered as adjunctive therapy in globe-sparing treatment of retinoblastoma.

Clinical and genetic associations for carboplatin-related ototoxicity in children treated for retinoblastoma: A retrospective noncomparative single-institute experience

BACKGROUND

Children with retinoblastoma treated with carboplatin chemotherapy risk moderate to severe, irreversible hearing loss. Based on published evidence, we hypothesized that ototoxicity risk is associated with clinical parameters and variants in candidate genes in drug metabolism pathways (methyltransferases [thiopurine S-methyltransferase, TPMT] and [catechol-O-methyltransferase, COMT], and drug transporter ABCC3).

PROCEDURE

We retrospectively reviewed clinical records of patients with retinoblastoma treated with carboplatin chemotherapy regarding age (at diagnosis and chemotherapy initiation), chemotherapy sessions (cycles number, drug doses, and cumulative carboplatin dose), and hearing loss (defined as ototoxicity ≥grade 2 by at least one classification system). Blood samples were genotyped for genetic variants in TPMT (rs12201199, rs1800460), COMT (rs4646316, rs9332377), and ABCC3 (rs1051640) by quantitative PCR and confirmed by allele-specific PCR. Univariate statistical tests, receiver-operating characteristic analysis, and Kaplan-Meier curves were used to examine the association between hearing loss, clinical factors, and variants in candidate genes.

RESULTS

Audiometric data and stored DNA were available for 71 patients with retinoblastoma (88% carried an RB1 pathogenic variant allele). Median carboplatin cumulative dose was 1,400 mg/m² (260-5,148 mg/m² ). Ototoxicity occurred in 18 patients (25%), strongly associated with age at diagnosis (P = 0.01) and age at chemotherapy initiation (OR = 4.99, P = 0.008). The highest likelihood ratio of hearing loss was associated with chemotherapy initiation <4.25 months of age. Ototoxicity was not associated with any tested genetic variants.

CONCLUSIONS

We observed a 25% prevalence of ototoxicity in patients with retinoblastoma treated with carboplatin, higher than previously published. Age at chemotherapy initiation was associated with carboplatin-induced ototoxicity, with children <4.25 months of age at highest risk.

Downregulation of NIMA-related kinase-7 inhibits cell proliferation by inducing cell cycle arrest in human retinoblastoma cells

NIMA-related kinase-7 (Nek7) is a centrosomal kinase involved in various types of cancer, including gallbladder cancer and hepatocellular carcinoma. However, the biological function and the potential underlying mechanism of Nek7 in retinoblastoma remain largely unknown. Therefore, the present study investigated the effects of Nek7 in retinoblastoma cells. The expression of Nek7 was initially determined and observed to be commonly upregulated in retinoblastoma cell lines (Y79, SO-RB50 and WERI-RB1) as compared with that in normal retinal pigment epithelium cells. Next, the endogenous expression of Nek7 was efficiently knocked down in Y79 and SO-RB50 cells using a lentivirus-mediated RNA interference approach, as confirmed by reverse transcription-quantitative polymerase chain reaction and western blot analysis. Loss-of-function assays, including MTT, colony formation and flow cytometry, indicated that knockdown of Nek7 significantly inhibited cell growth, impaired the colony formation ability and induced cell cycle arrest at G0/G1 phase. Furthermore, mechanistic studies demonstrated that silencing of Nek7 resulted in reduced cyclin-dependent kinase 2, cyclin D1 and cyclin E levels in vitro. In conclusion, the present study highlights the crucial role of Nek7 in promoting retinoblastoma cell proliferation, and Nek7-silencing may serve as a novel therapeutic target for retinoblastoma.

Challenges and differences in external radiation therapy for retinoblastoma: from standard techniques to new developments

AIMS

The purpose of this study is to calculate the treatment plans and to compare the dose distributions and dose-volume histograms (DVH) for 6 external radiotherapy techniques for the treatment of retinoblastoma as well as intensity-modulated radiotherapy (IMRT) and fractionated stereotactic radiotherapy (Cyberknife).

METHODS

Treatment plans were developed using 6 techniques, including an en face electron technique (ET), an anterior and lateral wedge photon technique (LFT), a 3D conformal (6 fields) technique (CRT), an inverse plan IMRT, tomotherapy, and conventional focal stereotactic external beam radiotherapy with Cyberknife (SBRT). Dose volume analyses were carried out for each technique.

RESULTS

All techniques except electron provided similar target coverage. When comparing conformal plan with IMRT and SBRT, there was no significant difference in planning target volume dose distribution. The mean volume of ipsilateral bony orbit received more than 20 Gy, a suggested threshold for bone growth inhibition. The V20 Gy was 73% for the ET, 57% for the LFT, 87% for the CRT, 65% for the IMRT, 66% for the tomotherapy, and 2.7% for the SBRT.

CONCLUSIONS

This work supports the potential use of IMRT and SBRT to spare normal tissues in these patients.

MicroRNA‑382 inhibits cell proliferation and invasion of retinoblastoma by targeting BDNF‑mediated PI3K/AKT signalling pathway

It has previously been demonstrated that multiple microRNAs (miRNAs or miRs) are aberrantly expressed in retinoblastoma (RB) and contribute to RB initiation and progression. miR‑382 has been revealed to be aberrantly expressed and therefore exhibits a key role in the progression of various types of cancer. However, the expression pattern, functional roles and underlying molecular mechanism of miR‑382 in RB remain unknown. The present study investigated the expression levels of miR‑382 and its effects on RB cells and the underlying regulatory mechanism of its action. It was demonstrated that miR‑382 was downregulated in RB tissues and cell lines. Upregulation of miR‑382 inhibited RB cell proliferation and invasion in vitro. Additionally, brain‑derived neurotrophic factor (BDNF) was identified as a novel target of miR‑382 in RB. BDNF was upregulated in RB tissues and negatively associated with miR‑382 expression levels. Furthermore, BDNF overexpression rescued the tumour‑suppressing effects on RB cells induced by miR‑382. miR‑382 inactivated the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signalling pathway in RB. These findings suggested that miR‑382 serves as a tumour suppressor in RB, in part, by targeting the BDNF‑mediated PI3K/AKT signalling pathway. The results of the present study suggest a potential therapeutic strategy for treating RB patients in the future.

Clinical outcome and regression patterns of retinoblastoma treated with systemic chemoreduction and focal therapy: A prospective study

Purpose:

To prospectively study the clinical outcome and regression patterns of early retinoblastoma (Groups A and B) after systemic chemotherapy and focal consolidation in Indian children.

Materials and Methods:

Group A eyes were treated with focal therapy (transpupillary thermotherapy/cryotherapy) and Group B with systemic chemoreduction and focal therapy. Outcome measures were efficacy and safety of treatment, risk factors for treatment failure, regression patterns, and factors predictive of regression patterns.

Results:

Of 119 eyes (216 tumors), 14 (11.8%) were Group A and 105 (88.2%) were Group B eyes. The mean follow-up was 22.6 months. Tumor control was achieved in 111/119 eyes (93.3% overall, 100% Group A, 92.4% Group B). Eight Group B eyes (6.7%) had treatment failure. No serious systemic side-effects were noted. Risk factors for failure included larger tumors (P = 0.001) and proximity to posterior pole (P = 0.014). Regression patterns were Type 4 (50.2%), Type 3 (31.7%), Type 1 (11.1%), and Type 2 (7%). Factors predictive of Type 4 regression were smaller tumors, anterior location, younger age; Type 3 regression was associated with larger tumors, macular location, and older age.

Conclusions:

Systemic chemoreduction and focal therapy provided effective tumor control in Indian children. Factors predictive of regression patterns included age, tumor size and its location, and the modality of treatment.

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.

MicroRNA-320 inhibits cell proliferation, migration and invasion in retinoblastoma by targeting specificity protein 1

Research into the expression and function of microRNAs (miRNAs/miR) in human cancer has provided novel insights into the molecular mechanisms underlying carcinogenesis and cancer progression. Aberrant miRNA expression has been reported in retinoblastoma (RB) and several other types of human cancer. The present study demonstrated that miR‑320 is significantly downregulated in RB tissues and cell lines. Furthermore, overexpression of miR‑320 was demonstrated to inhibit proliferation, migration and invasion of RB cells. Bioinformatic analysis identified specificity protein 1 (SP1) as a potential target gene of miR‑320. Luciferase reporter assay confirmed that the SP1 3'‑untranslated region contains a direct binding site for miR‑320, and restoration of miR‑320 expression decreased the mRNA and protein expression levels of SP1. Notably, SP1 silencing induced a similar effect on the proliferation, migration and invasion of RB cells as that observed with miR‑320 overexpression, further supporting the hypothesis that SP1 is a direct functional target of miR‑320 in RB. In conclusion, these findings indicate that miR‑320 may be an effective therapeutic target for the treatment of RB.

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.

microRNA-497 overexpression decreases proliferation, migration and invasion of human retinoblastoma cells via targeting vascular endothelial growth factor A

The expression level and roles of microRNA-497 (miR-497) have been frequently reported in previous studies on cancer. However, its expression, function and associated molecular mechanisms in retinoblastoma remain unknown. In the present study, miR-497 expression levels in human retinoblastoma tissues, normal retinal tissues and retinoblastoma cell lines were determined using reverse transcription-quantitative polymerase chain reaction. In addition, a Cell Counting Kit-8 assay, cell migration assay, cell invasion assay, western blot analysis and Dual-Luciferase reporter assay were used to explore the expression, functions and molecular mechanisms of miR-497 in human retinoblastoma. It was demonstrated that miR-497 was significantly downregulated in retinoblastoma tissues and cell lines compared with normal retinal tissues. Ectopic expression of miR-497 decreased the proliferation, migration and invasion of retinoblastoma cells. Furthermore, VEGFA was verified as a potential direct target of miR-497 in vitro. Taken together, the results indicate that miR-497 functions as a tumor suppressor in the carcinogenesis and progression of retinoblastoma via targeting VEGFA. miR-497 should be investigated as a potential therapeutic target for the treatment of retinoblastoma.

Ocular Salvage and Vision Preservation Using a Topotecan-Based Regimen for Advanced Intraocular Retinoblastoma

Purpose To evaluate topotecan-based therapy for advanced intraocular retinoblastoma. Patients and Methods Twenty-seven patients with bilateral retinoblastoma (male patients, n = 14; median age, 8.4 months) received chemotherapy: two courses of topotecan plus vincristine followed by three alternating administrations of carboplatin and vincristine for two courses and topotecan plus vincristine for one course, with optional periocular carboplatin. Focal therapy was applied after cycle 2. Event-free survival was defined as avoidance of external-beam radiotherapy (EBRT) and enucleation. Results Of 54 eyes, 42 were Reese-Ellsworth group IV to V, and 37 were International Classification of Retinoblastoma group C to E. Eleven eyes were enucleated: one at diagnosis, nine with progressive disease including three eyes treated with EBRT, and one that developed neovascular glaucoma after completion of therapy. One patient was removed from protocol with prolonged infection in course 1; 26 patients (51 eyes) were analyzed. At 10 years, cumulative incidence of EBRT was 5.9% (SE ± 3), and event-free survival was 69.2% (SE ± 27.2). Ocular survival for Reese-Ellsworth group IV to V eyes was 77.5% (SE ± 21.2); it was 74.3% (SE ≥ 18.8) for International Classification group C to E eyes. Vision testing (median age, 7 years; range, 5 to 10 years) documented 20/70 vision or better in one eye of 23 patients; 19 (76%) of 25 patients demonstrated 20/40 vision or better in one eye. All patients experienced thrombocytopenia (41 episodes in 275 courses; 15%). There were 29 episodes of febrile neutropenia (10%). Grade 3 diarrhea was present in nine of 27 patients, and one patient had an allergic reaction to carboplatin. All patients are alive at median follow-up 7.4 years (range, 2.7 to 10 years). Conclusion Topotecan combined with vincristine, carboplatin, and aggressive focal therapies is an effective regimen for the treatment of advanced retinoblastoma and results in globe salvage with vision. Toxicities were anticipated and managed with appropriate supportive care.

Long-term audiologic follow-up of carboplatin-treated children with retinoblastoma

BACKGROUND

Children treated for retinoblastoma with carboplatin have an increased risk for ototoxicity. Impaired hearing may have major consequences for these children, because they often suffer from reduced vision. Previous studies have shown limited information on the incidence and severity of carboplatin-induced ototoxicity and the used audiologic methods. The frequency of audiological testing is often limited and the audiologic follow-up time is relatively short.

OBJECTIVE

The aim of this study was to determine the long-term effects of carboplatin ototoxicity in children with retinoblastoma.

MATERIALS AND METHODS

In this retrospective non-randomized single center cohort study, we reviewed audiologic results of 25 patients. Experienced audiologists analyzed the pure-tone audiograms.

RESULTS

All patients had normal hearing prior to therapy and had a mean age of 11 months at first carboplatin administration. The mean audiologic follow-up was 12.0 years with a median of 11.6 (IQR 4.8) years. Three patients were excluded: two passed away and one could not participate in the audiologic tests. One of the 22 included patients developed sustained low-grade bilateral high-frequency hearing loss between 2 and 7 years after the last carboplatin dose. In one patient it was not possible to make a reliable conclusion due to a conductive hearing loss component. Twenty patients had normal hearing.

CONCLUSIONS

We observed no clear effect between carboplatin administration in young children and clinical significant ototoxicity in the long term. One child showed low-grade bilateral high-frequency hearing loss.

The Evolution of Radiation Therapy for Retinoblastoma: The MD Anderson Cancer Center Experience

Purpose

The role of radiation therapy (RT) for retinoblastoma (Rb) has significantly evolved from first-line to salvage therapy. The objectives of our study were to evaluate efficacy of proton RT (PRT) and other advanced RT techniques for Rb and to observe evolving trends in RT use.

Materials and Methods

An analysis of patients with Rb who received RT between 1990 and 2012 was conducted. Thirty-nine patients with 70 affected eyes were identified. Of these, 47 eyes were treated with RT with photon or electron RT (ERT), PRT, or brachytherapy (BRT). The clinical history, treatment details, and tumor outcomes were reviewed for all patients.

Results

Radiation therapy was first-line treatment in 14 eyes, second-line in 4, postoperative in 4, and salvage in 25. Median length of follow-up was 8 years for all patients, and 10, 3, and 5 years for ERT, PRT, and BRT, respectively. Overall survival was 97.4%. In total, 16 (34.0%) eyes required enucleation after RT. Median PRT dose was 36 Gy (RBE) (range, 36-45 Gy [RBE]), ERT dose was 45 Gy (range, 36-46 Gy), and BRT dose was 45 Gy (range, 36-45 Gy). A higher proportion of PRT patients (93.8%) than ERT patients (51.9%) were treated in the salvage setting (P < .01). Among patients with International Classification for Intraocular Retinoblastoma stage D and E disease, 6 of 11 (54.5%) ERT patients required enucleation and 5 of 13 (38.5%) PRT patients required enucleation.

Conclusion

This study represents a large series of patients treated with PRT, ERT, and BRT for Rb and reports favorable efficacy and toxicity. Patients treated with salvage PRT are typically heavily pretreated and have advanced disease. Despite more advanced disease, patients treated with PRT with lower RT doses achieve comparable salvage and enucleation-free rates to ERT. Chemoreduction followed by focal treatments should be standard of care when clinically feasible, with PRT considered in the salvage setting.

Comparison of high-risk histopathological features in eyes with primary or secondary enucleation for retinoblastoma

AIMS

To compare high-risk histopathology of eyes with primary versus secondary enucleation from patients with retinoblastoma.

PATIENTS AND METHODS

A retrospective histopathology review identified 207 eyes enucleated from 202 patients between March 1997 and August 2013. Our review considered high-risk histopathological features to include extraocular disease or invasion of the anterior chamber, iris, ciliary body, choroid (massive), postlaminar optic nerve or sclera.

RESULTS

Most eyes (144, 70%) were primarily enucleated; 63 (30%) were secondarily enucleated after neoadjuvant therapy. The primary enucleation group had more advanced disease (Reese-Ellsworth group V: 95% vs 59%; International Classification Group D/E: 97% vs 59%; p<0.001). The incidence of high-risk histopathology features was similar between groups (32% vs 21%, n=59; p=0.132). The type of prior therapy was not associated with high-risk histopathology features. Time to enucleation was longer for secondarily enucleated eyes with high-risk features. Choroid and postlaminar optic nerve invasion were more frequent in eyes primarily enucleated (p<0.001). Forty-six of the 59 (78%) patients with high-risk features received adjuvant chemotherapy and/or external beam radiation therapy. Three patients who received primary enucleation and adjuvant therapy died of metastatic recurrence.

CONCLUSIONS

Despite the more favourable classification of eyes treated with neoadjuvant therapy, the risk of high-risk histopathology features at enucleation was comparable with eyes undergoing primary enucleation. Delayed enucleation was associated with these features, and the majority of patients required further adjuvant therapy. Caution must be exercised in treating recalcitrant intraocular retinoblastoma to promptly pursue definitive enucleation in an effort to minimise further treatment exposures and metastases.

[Genetic analysis results of patients with a retinoblastoma refractory to systemic chemotherapy]

OBJECTIVE

To analyze the genetic alterations identified in the RB1 gene in retinoblastoma patients who do not respond to systemic chemotherapy.

METHODS

A genetic analysis was performed on 115 patients with retinoblastoma, 40 of whom had received systemic chemotherapy, and 29 of them had bilateral disease. Descriptive and retrospective study. Non-responders were considered as patients who are finally enucleated.

RESULTS

Patients with deletion type mutations are those with less preservation of the eyeball (Pearson Chi-square, P=.055). Patients with an impaired nonsense-frameshift type are more likely to preserve the eyeball. Of the 3 patients who had undergone bilateral enucleation, 2 of them had deletions and one missense alteration. Survival analysis (Kaplan-Meier curve) shows that patients with deletion type mutations are more resistance to chemotherapy, are suffering higher rates of enucleation, and for a shorter period of time (log rank [Mantel-Cox] with a significance level of P=.053), which are also associated with increased rate of being bilateral.

CONCLUSIONS

Patients with a genotype show increased resistance to chemotherapy should be evaluated more closely and treated with various therapeutic weapons early. Patients that have deletions in the RB1 gene are at increased risk of chemoresistance. It is likely that other genetic alterations other than RB1 gene may be related to tumor aggressiveness and treatment resistance.

Management of retinoblastoma: opportunities and challenges

Nano-delivery systems have significantly evolved over the last decade for the treatment of cancer by enabling site-specific delivery and improved bioavailability. The widely investigated nanoparticle systems are biodegradable polyesters, dendrimers, liposomes, mesoporous silica and gold nanoparticles. These particles when conjugated with different targeting motifs enhance the therapeutic efficiency of the drug molecules and biocompatibility. However, the application of such systems towards the treatment of retinoblastoma (RB), a rapidly spreading childhood eye cancer, still remains in its infancy. Nanoparticle-based systems that have been investigated for RB therapy have displayed improved drug delivery to the most restricted posterior segment of the eyes and have increased intra-vitreal half-life of the chemotherapy agents highlighting its potential in treatment of this form of cancer. This review focuses on the challenges involved in the treatment of RB and highlights the attempts made to develop nano-dimensional systems for the treatment of RB.

Retinoblastoma. Fifty years of progress. The LXXI Edward Jackson Memorial Lecture

PURPOSE

To review the progress made in understanding the genetic basis, molecular pathology, and treatment of retinoblastoma since the previous Jackson lecture on the topic was published 50 years ago.

DESIGN

Perspective based on personal experience and the literature.

METHODS

The literature regarding retinoblastoma was reviewed since 1963. Advances in understanding the biology and treatment of retinoblastoma provided context through the author's clinical, pathologic, and research experiences.

RESULTS

Retinoblastoma was first identified in the 1500s and defined as a unique clinicopathologic entity in 1809. Until the mid-1900s, knowledge advanced sporadically, with technological developments of ophthalmoscopy and light microscopy, and with the introduction of surgical enucleation, chemotherapy, and radiation therapy. During the last 50 years, research and treatment have progressed at an unprecedented rate owing to innovations in molecular biology and the development of targeted therapies. During this time period, the retinoblastoma gene was discovered; techniques for genetic testing for retinoblastoma were developed; and plaque brachytherapy, chemoreduction, intra-arterial chemotherapy, and intraocular injections of chemotherapeutic agents were successfully introduced.

CONCLUSIONS

Nearly all patients with retinoblastoma in developed countries can now be cured of their primary cancer--a remarkable achievement for a childhood cancer that once was uniformly fatal. Much of this success is owed to deciphering the role of the Rb gene, and the benefits of targeted therapies, such as chemoreduction with consolidation as well as intra-arterial and intravitreal chemotherapies. Going forward, the main challenge will be ensuring that access to care is available for all children, particularly those in developing countries.

High-dose chemotherapy with autologous stem cell rescue for treatment of retinoblastoma: report of five cases

RB is a primarily pediatric cancer arising from the retina, initiated by biallelic loss of the RB1 gene. We report five children with bilateral RB (n = 3), extra-ocular disseminated RB, or disseminated relapsed RB, who were treated with tandem high-dose chemotherapy and autologous stem cell rescue. All patients received at least 2.2 × 10(6) /kg CD34(+) (median, 3.9 × 10(6) /kg) cells. The preparative regimen for course 1 was carboplatin, thiotepa, etoposide, and for course 2, CM and melphalan. ANC of at least 0.5 × 10(9) /L occurred at a median of 11 days (range, 10-12) and 15 days (range, 12-16) after the first and second procedure, respectively. Platelet engraftment occurred at a median of 13 days (range, 12-17) and 15 days (range, 14-22) after the first and second procedure, respectively. All of the five patients treated remain alive and disease free at the last follow-up time, ranging between 21 and 44 months after completion of autologous transplant. Additional therapy was required in one patient, in whom enucleation had to be performed because of early disease relapse, refractory to local therapy. Intensification of chemotherapy with repeated high-dose chemotherapy and autologous rescue appears an acceptable choice in selected cases with bilateral or extra-ocular disease, either recurrent or refractory.

Expression of P-glycoprotein in human retinoblastoma and its clinical significance

Retinoblastoma is the most common malignant intraocular tumor of childhood. Drug resistance and relapses are major problems with chemotherapy, which is regarded as the mainstay of globe preserving treatment in retinoblastoma. P-glycoprotein (P-gp) expression has been reported to be associated with chemoresistance and poor prognosis in various malignancies. We analyzed P-gp expression in retinoblastoma specimens, enucleated either primarily or after neoadjuvant chemotherapy by immunohistochemistry and immunoblotting, and correlated with the histopathological findings. Variables were statistically analyzed by Fischer's exact and chi-square tests. Tumor tissues were collected from enucleated eyes of 24 children. Fifteen of these were primarily enucleated (group I), and nine (group II) had received chemotherapy prior to enucleation. P-gp was expressed in 4/15 (26.7 %) eyes in group I and in 5/9 (55.6 %) eyes in group II. P-gp was highly expressed in group II as compared to group I. There was no correlation between P-gp expression and tumor differentiation, invasion, or laterality. In conclusion, there was markedly high expression of P-gp in eyes with retinoblastoma enucleated after chemotherapy. This may possibly play a role in chemoresistance or it may be that chemotherapy might have induced high expression. These findings may have important implications for the treatment of retinoblastoma patients but need further prospective investigations in a larger patient population.

Chebulagic acid from Terminalia chebula causes G1 arrest, inhibits NFκB and induces apoptosis in retinoblastoma cells

Background

Plants are the valuable source of natural products with important medicinal properties. Most of the approved anti cancer drugs have a natural product origin or are natural products. Retinoblastoma is the most common ocular cancer of children. Although chemotherapy is the preferred mode of therapy, a successful treatment for retinoblastoma requires enucleation. Chebulagic acid (CA) from Terminalia chebula was shown to have anti-proliferative properties in the studies on cancerous cell lines. Due to anti cancer properties of CA and due to limitation in treatment options for retinoblastoma, the present study is undertaken to understand the role of CA on the proliferation of retinoblastoma cells.

Methods

Anti proliferative potential of CA was determined by MTT assay. The expression levels of various cell death mediators in retinoblastoma cells with CA treatment were assessed by Western blotting. Flowcytometer analysis was used to estimate the mitochondrial membrane potential (MMP) and to determine the percentage of cells undergoing apoptosis.

Results

The present study showed CA inhibited the proliferation of retinoblastoma cells in a dose dependent manner. CA modulated MMP, induced release of Cytochrome c, activated caspase 3 and shifted the ratio of BAX and Bcl2 towards cell death. G1 arrest, noticed in CA treated cells, is mediated by the increase in the expression of CDK inhibitor p27. CA treatment also decreased the levels of NFκB in the nucleus. This decrease is mediated by suppression in degradation of IκBα.

Conclusion

CA has shown significant anti proliferative potential on retinoblastoma cells. Our findings clearly demonstrate that CA induces G1 arrest, inhibits NFκB and induces apoptosis of retinoblastoma cells.

A 10-year experience of outcome in chemotherapy-treated hereditary retinoblastoma

PURPOSE

The aim is to report the 10-year retrospective experience of systemic chemotherapy for a population-based group of patients with hereditary retinoblastoma at a national referral centre. The outcomes include control rates, treatment side-effects, adjuvant therapy, failure rate, survival, secondary cancers and visual acuity.

METHODS

All patients (n = 24, 46 eyes) diagnosed with retinoblastoma and treated with systemic chemotherapy at a national referral centre during 2001-2011 were included. Data were extracted from medical records.

RESULTS

The patients were followed for a mean of 60 months (range 13-144). Four-six cycles of VEC was administered to all newly diagnosed group B/C/D/E eyes with bilateral disease and 83% (38 of 46) responded to the treatment. None of the patients discontinued chemotherapy because of adverse reactions. Altogether 26% (12 of 46) of the eyes received second-line therapy (other than thermotherapy, cryotherapy and chemotherapy). The failure rate was 35% (16 of 46) and mortality rate 0%. None of the patients developed CNS manifestations (metastases or trilateral retinoblastoma). One of the patients developed a second primary tumour (osteosarcoma) 4 years following retinoblastoma diagnosis. Altogether 17% (4 of 24) patients received radiation therapy, 28% (13 of 46) of the eyes had to be enucleated, and one patient underwent bilateral enucleation. The age-correlated visual acuity was mean of 73% of expected visual acuity.

CONCLUSION

Group A/B retinoblastomas have a distinct chemotherapy response, while group C/D/E tumours do not respond as well. The success rate was 65%; while patients have a good prognosis for life, approximately one-third of all hereditary cases received radiation therapy or underwent enucleation.