Risk factors for extraocular relapse following enucleation after failure of chemoreduction in retinoblastoma

Correlation of clinical and radiological predictors of retinoblastoma with high-risk histopathological features

INTRODUCTION

Retinoblastoma (RB) tumors having high-risk histopathologic features (HRFs) have an increased risk of metastasis and disease relapse. However, RB has not been studied widely in Pakistan. Therefore, we evaluated the association of clinical, histopathologic, and radiological findings with HRFs in patients with RB who were treated at the Indus Health & Hospital Network in Karachi, Pakistan.

METHODS

We enrolled treatment-naïve patients with RB who received upfront enucleation from September 2017 to February 2021. We evaluated enucleated eyes with the Intraocular Classification of Retinoblastoma system and classified HRFs as invasion of the anterior chamber, including the iris and ciliary body, or massive invasion of the choroid, sclera, or optic nerve (postlaminar and/or up to the transection line).

RESULTS

Of 117 patients with RB treated at our institution during the study period, 54 received upfront enucleation. Unilateral disease was present in 92.6% of cases. The most frequent disease signs and symptoms included the presence of vitreous seeds (30.6%) and leukocoria (100%), respectively. The most frequent HRFs and radiological findings comprised massive choroidal invasion (15.1%) and anterior chamber enhancement (66.7%), respectively. The majority (62.9%) of patients did not exhibit any HRFs. Female sex, pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma had significant predictive ability for HRF occurrence.

CONCLUSION

Pseudohypopyon, iris neovascularization, buphthalmos, and glaucoma are important clinical factors that should be taken into consideration before the management of RB. Early recognition of high-risk histopathological and radiological features is essential for appropriate treatment of RB.

Current Indications of Secondary Enucleation in Retinoblastoma Management: A Position Paper on Behalf of the European Retinoblastoma Group (EURbG)

Simple Summary

Although secondary enucleation (SE) is the treatment of choice for retinoblastoma eyes that did not respond favorably to conservative therapies, clear criteria for its indication are, however, currently missing. In this position paper on behalf of the European Retinoblastoma Group (EURbG), we discuss the available literature on SE, including its influence on metastases rate and survival, and propose guidelines to assist decision-making to interrupt eye-preserving therapies depending on the availabilities of advanced diagnostic and therapeutic modalities. Absolute indications to SE may be restricted to eyes with refractory tumor activity resisting all salvage treatments or eyes under apparent tumor control but no visual potential and irreducible complications. In contrast, eyes with an obscured optic nerve head and/or ocular complications amenable to specific surgical or medical management can be considered relative indications, provided that appropriate follow-up can be implemented and that parents are fully aware of a residual risk.

Abstract

Secondary enucleation (SE) puts an irreversible end to eye-preserving therapies, whenever their prolongation is expected to violate the presumed state of metastatic grace. At present, it must be acknowledged that clear criteria for SE are missing, leading to empiric and subjective indications commonly related to disease progression or relapse, disease persistence masking the optic nerve head or treatment-related complications obscuring the fundus view. This absence of evidence-based consensus regarding SE is explained by the continuously moving frontiers of the conservative management as a result of diagnostic and therapeutic advances, as well as by the lack of studies sufficiently powered to accurately stratify the risk of metastasis in conservatively treated patients. In this position paper of the European Retinoblastoma Group (EURbG), we give an overview of the progressive shift in the indications for SE over the past decades and propose guidelines to assist decision-making with respect to when SE becomes imperative or recommended, with corresponding absolute and relative SE indications. Further studies and validation of biologic markers correlated with the risk of metastasis are expected to set more precisely the frontiers of conservative management and thus consensual criteria for SE in the future.

Stem-Cell Therapy Following High-Dose Chemotherapy in Advanced Retinoblastoma: A Systematic Review

PURPOSE

To analyze the risk and benefit of high-dose chemotherapy followed by stem cell transplantation (HDCT-SCT) treatment in patients with advanced retinoblastoma.

DESIGN

Systematic review.

METHODS

A comprehensive literature search from 4 online databases, including PubMed, Scopus, EBSCO, and Cochrane was done for original studies evaluating the use of HDCT followed by SCT in the treatment of patients with advanced retinoblastoma. The last search was performed on April 15, 2020.

RESULTS

A total of 35 studies consisting of 160 patients were considered suitable for inclusion. After HDCT-SCT treatment, 108/160 (67.5%) patients were alive with no evidence of disease at the last follow-up. The incidence of secondary malignancy in our data was also relatively low, which was 16/160 (10%) patients. The side effects were mainly hematological and gastrointestinal toxicities. The prognosis for metastatic cases especially the one to the central nervous system (CNS) remains poor, as shown in our data that 22 of 44 (50%) patients died due to the evidence of disease, and 12 of 44 (27%) patients acquired CNS relapse and died.

CONCLUSIONS

HDCT-SCT is a promising treatment option in patients with advanced retinoblastoma. The use of HDCT-SCT in CNS metastases needs to be carefully considered, possibly by adding thiotepa or topotecan to improve tumor control. Further randomized clinical trials are needed to draw firm conclusion regarding its safety and efficacy.

Bone metastasis of retinoblastoma five years after primary treatment

Purpose

Histopathological, immunohistochemistry- and molecular pathology-based diagnostics to distinguish metastasis of retinoblastoma from subsequent primary malignancy in patients with heritable retinoblastoma.

Observations

An eight year-old girl presented with tibial pain and bone lesion five years after multimodal treatment of bilateral retinoblastoma, initially clinically suspicious of osteomyelitis. Histopathological examination of bone biopsy specimen revealed a highly proliferative small blue round cell tumor mimicking Ewing's sarcoma of bone. Immunohistochemistry confirmed the diagnosis of a distant metastasis of the previous retinoblastoma. Other subsequent primary malignancies presenting as small blue round cell tumors, such as sarcomas or leukemia, were excluded by immunohistochemistry and molecular methods.

Conclusions and importance

In countries with early diagnosis of retinoblastoma, distant metastases of retinoblastoma are extremely rare, whereas subsequent primary malignancies are common in survivors of heritable retinoblastoma. Immunohistochemistry and molecular pathology are essential components of diagnostic pathway. In retinoblastoma patients, distant metastases including osseous lesions should be included in the differential diagnosis of small blue round cell tumors.

Management of advanced uni- or bilateral retinoblastoma with macroscopic optic nerve invasion

BACKGROUND

Retinoblastoma with macroscopic optic nerve (ON) invasion depicted by imaging at diagnosis remains a major problem and carries a poor prognosis. We sought to describe the treatment and outcome of these high-risk patients.

METHODS

Retrospective mono-institutional clinical, radiological, and histological review of patients with uni- or bilateral retinoblastoma with obvious ON invasion, defined by radiological optic nerve enlargement (RONE) depicted by computed tomography scan or magnetic resonance imaging (MRI), was performed.

RESULTS

Between 1997 and 2014, among the 936 patients with retinoblastoma treated at Institut Curie, 11 had detectable RONE. Retinoblastoma was unilateral in 10 and bilateral in one. Median age at diagnosis was 28 months (range, 11-96). ON enlargement extended to the orbital portion in three patients, to the optic canal in five, to the prechiasmatic portion in two, and to the optic chiasm in one. Nine patients received neoadjuvant chemotherapy and partial response was obtained in all. Enucleation was performed in 10/11 patients-by an anterior approach in three and by anterior and subfrontal approaches in seven. Three patients had a positive ON resection margin (2/3 after primary enucleation). All enucleated patients received adjuvant treatment (conventional chemotherapy: 10, high-dose chemotherapy: seven, radiotherapy: five). Leptomeningeal progression occurred in four patients. Seven are in first complete remission (median follow up: 8 years [3.5-19.4]).

CONCLUSION

Neoadjuvant chemotherapy and microscopic complete resection have a pivotal role in the management of retinoblastoma with RONE. MRI is recommended for initial and pre-operative accurate staging. Surgery should be performed by neurosurgeons in case of posterior nerve invasion. Radiotherapy is required in case of incomplete resection.

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

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

Metastatic retinoblastoma of the parotid and submandibular glands: a rare case report

Background

Retinoblastoma is the most common intraocular malignancy occurring in children. It can metastasize to the regional lymph nodes, central nervous system and distant organs usually the bones and bone marrow and very rarely to the soft tissue. Here, we report a case of unilateral retinoblastoma in a 4-year-old girl accompanied by a large metastasis of the parotid and submandibular glands that developed about 6 months previously and gradually increased in size 5 months after enucleation of the left eye.

Case presentation

A 4-year-old girl with a history of unilateral retinoblastoma presented with a large, painful and worsening mass (about 20 × 23 cm) of the left side of the neck. Following surgery, the orbital tumour was completely resected, and the large tumour invasion range in the left side of the neck was not resected completely. Histopathological examination revealed retinoblastoma of the orbit and the parotid and submandibular glands. After chemotherapy and additional local radiotherapy on the parotid and submandibular glands, the tumour was inactive and stable.

Conclusions

Delayed detection and inappropriate management contribute to poor outcomes. Fundus examinations, education regarding the early signs of RB, and optimization of the therapeutic strategy for RB may play important roles in ocular health.

9.4T and 17.6T MRI of Retinoblastoma: Ex Vivo evaluation of microstructural anatomy and disease extent compared with histopathology

BACKGROUND

Retinoblastoma is the most common intraocular tumor in childhood with a good prognosis in terms of mortality, but detailed information about tumor morphology and disease extent in retinoblastoma is important for treatment decision making.

PURPOSE

To demonstrate ultrahigh-field MRI tumor morphology and tumor extent in retinoblastoma correlating with in and ex vivo images with histopathology.

STUDY TYPE

Prospective case series.

POPULATION

Six retinoblastoma patients (median age 5.5 months, range 2-14) were prospectively included in this study. Median time between diagnosis and enucleation was 8 days (range 7-19).

FIELD STRENGTH/SEQUENCE

In vivo pre-enucleation at 1.5T MRI with a circular surface coil. Ex vivo imaging (FLASH T₁ -weighted and RARE T₂ -weighted) was performed at field strengths of 9.4T and 17.6T.

ASSESSMENT

After ex vivo imaging, the eyes were histopathologically analyzed and morphologically matched with MRI findings by three authors (two with respectively 14 and 4 years of experience in ocular MRI and one with 16 years of experience in ophthalmopathology).

RESULTS

Small submillimeter morphological aspects of intraocular retinoblastoma were successfully depicted with higher-resolution MRI and matched with histopathology images. With ex vivo MRI a small subretinal tumor seed (300 μm) adjacent to the choroid was morphologically matched with histopathology. Also, a characteristic geographical pattern of vital tumor tissue (400 μm) surrounding a central vessel interspersed with necrotic areas correlated with histopathology images. Tumor invasion into the optic nerve showed a higher signal intensity on T₁ -weighted higher-resolution MRI.

DATA CONCLUSION

Higher-resolution MRI allows for small morphological aspects of intraocular retinoblastoma and extraocular disease extent not visible on currently used clinical in vivo MRI to be depicted.

LEVEL OF EVIDENCE

4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1487-1497.

Preclinical platform of retinoblastoma xenografts recapitulating human disease and molecular markers of dissemination

Translational research in retinoblastoma - a pediatric tumor that originates during the development of the retina - would be improved by the creation of new patient-derived models. Using tumor samples from enucleated eyes we established a new battery of preclinical models that grow in vitro in serum-free medium and in vivo in immunodeficient mice. To examine whether the new xenografts recapitulate human disease and disseminate from the retina to the central nervous system, we evaluated their histology and the presence of molecular markers of dissemination that are used in the clinical setting to detect extraocular metastases. We evaluated GD2 synthase and CRX as such markers and generated a Taqman real-time quantitative PCR method to measure CRX mRNA for rapid, sensitive and specific quantification of local and metastatic tumor burden. This approach was able to detect 1 human retinoblastoma cell in 100.000 mouse brain cells. Our research adds novel preclinical tools for the discovery of new retinoblastoma treatments for clinical translation.

Disparities in Retinoblastoma Presentation, Treatment, and Outcomes in Developed and Less-Developed Countries

Retinoblastoma (RB) is the most common intraocular malignancy in children. In the past century, RB survival rates in developed countries (DCs) have improved from <5% to as high as 99%. In contrast, in less developed countries (LDCs) where the tumor burden is greatest, survival rates remain poor, with some countries reporting survival rates as low as 0-5%. In addition, there are disparities between DCs and LDCs in RB presentation, treatment modalities, and prognosis. These disparities are due to many underlying causes, including delays in diagnosis, access to medical care, patient and physician familiarity with the disease, availability and cost of treatment, and patient acceptance of enucleation. It is our belief that attempts to extend the improvements in prognosis achieved in DCs to various LDCs must be culturally sensitive and tailored to each country's specific challenges, and thus, a "one-size-fits-all" approach to improving patient outcomes in LDCs is unlikely to work well. We discuss several culturally sensitive approaches that have been successfully implemented in various LDCs, including those that make use of telemedicine and "twinning" with centers of excellence around the world.

Diagnostic Accuracy of Intraocular Tumor Size Measured with MR Imaging in the Prediction of Postlaminar Optic Nerve Invasion and Massive Choroidal Invasion of Retinoblastoma

Purpose To assess the correlation of intraocular retinoblastoma tumor size measured with magnetic resonance (MR) imaging in the prediction of histopathologically determined metastatic risk factors (postlaminar optic nerve invasion and massive choroidal invasion). Materials and Methods The ethics committee approved this retrospective multicenter study with a waiver of informed consent. The study population included 370 consecutive patients with retinoblastoma (375 eyes) who underwent baseline MR imaging, followed by primary enucleation from 1993 through 2014. Tumor sizes (maximum diameter and volume) were measured independently by two observers and correlated with histopathologic risk factors. Receiver operating characteristic curves were used to analyze the diagnostic accuracy of tumor size, and areas under the curve were calculated. Logistic regression analysis was performed to evaluate potential confounders. Results Receiver operating characteristic analysis of volume and diameter, respectively, yielded areas under the curve of 0.77 (95% confidence interval [CI]: 0.70, 0.85; P < .0001) and 0.78 (95% CI: 0.71, 0.85; P < .0001) for postlaminar optic nerve invasion (n = 375) and 0.67 (95% CI: 0.57, 0.77; P = .0020) and 0.70 (95% CI: 0.59, 0.80; P = .0004) for massive choroidal tumor invasion (n = 219). For the detection of co-occurring massive choroidal invasion and postlaminar optic nerve invasion (n = 219), volume and diameter showed areas under the curve of 0.81 (95% CI: 0.70, 0.91; P = .0032) and 0.83 (95% CI: 0.73, 0.93; P = .0016), respectively. Conclusion Intraocular tumor size shows a strong association with postlaminar optic nerve invasion and a moderate association with massive choroidal invasion. These findings provide diagnostic accuracy measures at different size cutoff levels, which could potentially be useful in a clinical setting, especially within the scope of the increasing use of eye-salvage treatment strategies. (©) RSNA, 2015 Online supplemental material is available for this article.

Risk definition and management strategies in retinoblastoma: current perspectives

This manuscript focuses on high-risk factors of metastatic disease in retinoblastoma and evaluation of the current treatments of retinoblastoma. Presence of histopathologic high-risk factors is associated with a higher risk of local recurrence and systemic metastasis. Currently, globe-sparing therapies, including systemic chemotherapy, intra-arterial chemoreduction, intravitreal chemotherapy, focal consolidation, and combination therapies, are being used and investigated actively. Major advances are being made in the diagnosis and management of retinoblastoma that will lead to improved morbidity and mortality rates in patients with retinoblastoma. By saving the globes, fronting with some high-risk factors for metastasis would be inevitable. International multi-institutional prospective studies could resolve current uncertainties regarding the main tumor treatment regimens for each patient and indications for chemoprophylaxis for high-risk-factor-bearing retinoblastoma cases.

Management of retinoblastoma in children: current status

In recent years, there have been dramatic changes in the management of intraocular retinoblastoma. Intraocular retinoblastoma is a highly curable malignancy and current treatments are aimed to preserve vision while reducing the late effects such as treatment-induced secondary malignancies. The advent of intra-arterial chemotherapy changed the treatment paradigm from systemic treatment with chemotherapy to local treatment, and new questions emerged. While intra-arterial chemotherapy achieved encouraging results, only experience from major referral centers is reported, so its indications, advantages and risks are still to be elucidated. Many factors should be considered when choosing the appropriate conservative therapy. When the disease has extended outside the eye, the chances of cure are significantly lower and treatment should be tailored by the presence of pathology risk factors such as invasion of the choroid, the optic nerve, and the sclera. Adjuvant therapy is decided upon this information. Children with overt extraocular disease are treated with higher dose neoadjuvant therapy followed by delayed enucleation and adjuvant therapy.

Very late relapse of bilateral retinoblastoma

Retinoblastoma usually recurs within the first few years after treatment completion. We report a rare case of very late relapse in a 6-month-old girl who was diagnosed with bilateral retinoblastoma. The patient achieved first remission after treatment with neoadjuvant chemotherapy, enucleation of the right eye, local laser therapy of the left eye, and adjuvant chemotherapy. Extraocular relapse with multiple metastases occurred 13 years and 8 months after treatment. The patient is currently in second complete remission after receiving high-dose chemotherapy and autologous stem cell transplantation. In conclusion, long-term follow-up is needed for early detection of recurrent retinoblastoma.

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.

Intra-arterial chemotherapy is more effective than sequential periocular and intravenous chemotherapy as salvage treatment for relapsed retinoblastoma

BACKGROUND

Treatment of eyes with retinoblastoma failing systemic chemoreduction and external beam radiotherapy is seldom efficacious. This study compares the efficacy and toxicity of intra-arterial ophthalmic artery chemotherapy (IAO) to our historical cohort of sequential periocular and systemic chemotherapy in such patients.

PATIENTS AND METHODS

Eighteen eyes (15 consecutive patients) were retrospectively evaluated. Eight eyes received IAO for a median of four cycles (range: 2-9) including melphalan alone (n = 3) or after topotecan and carboplatin (n = 4) or topotecan and carboplatin without melphalan (n = 1). Ten eyes received a median of two cycles (range: 1-3) of periocular topotecan (n = 9) or carboplatin (n = 1) followed by intravenous topotecan and cyclophosphamide in three patients if at least stable disease was achieved. Both groups were comparable for disease extension and prior therapy.

RESULTS

No extraocular dissemination or second malignancy occurred and all patients are alive. The probability of enucleation-free eye survival at 12 months was 0.87 (95% CI: 0.42-0.97) for the IAO group, compared to 0.1 (95% CI: 0.06-0.35) for the periocular group (P < 0.01). Ocular toxicity was mild and similar in both groups (mostly mild orbital edema). Systemic toxicity was low for IAO and periocular injection, but children who received sequentially intravenous chemotherapy (n = 12 cycles) had five episodes of grade 4 neutropenia, three of which resulted in hospitalizations. No case in the IAO group presented these complications.

CONCLUSIONS

IAO is significantly superior to sequential periocular-intravenous topotecan-containing regimens in eyes with relapsed intraocular retinoblastoma with a more favorable toxicity profile.

Retinoblastoma: value of dynamic contrast-enhanced MR imaging and correlation with tumor angiogenesis

BACKGROUND AND PURPOSE

Noninvasive evaluation of retinoblastoma treatment response has become more important due to increased use of eye-sparing treatments. We evaluated the relation between DCE-MR imaging and histopathologic parameters to determine the value of DCE-MR imaging in assessing tumor angiogenesis and prognostic features.

MATERIALS AND METHODS

Fifteen consecutive patients with retinoblastoma (mean age, 24 months; range, 2-70 months) undergoing enucleation as the primary treatment (15 eyes) were scanned at 1.5T by using dedicated surface coils. Pretreatment DCE-MR imaging of the most affected eye was evaluated by 2 observers by using curve-pattern analysis, with the first 5 minutes of each curve and the full time-series described as κ(5min) and κ(17min), respectively. Assessed histopathologic and immunologic parameters included optic nerve invasion, choroid invasion, MVD, tumor necrosis, and expression of VEGF and Flt-1.

RESULTS

The median value of κ(5min) was 1.28 (range, 0.87-2.07) and correlated positively with MVD (P = .008). The median value of κ(17min) was 1.33 (range, 0.35-3.08) and correlated negatively with tumor necrosis (P = .002). Other histopathologic and immunohistopathologic parameters did not correlate with DCE-MR imaging parameters. Interobserver agreement was 0.53 for κ(5min) and 0.91 for κ(17min).

CONCLUSIONS

In retinoblastoma, the early phase of the DCE time curve positively correlates with MVD, while the presence of late enhancement is correlated with necrosis. Thus, the potential for DCE-MR imaging to noninvasively assess tumor angiogenesis and necrosis in retinoblastoma is promising and warrants further investigation.

Abnormal orbital growth in children submitted to enucleation for retinoblastoma treatment

Enucleation is typically performed for the treatment of advanced retinoblastoma in children. After enucleation, the orbit undergoes abnormal development. In this study, orbital asymmetry was calculated using computed tomography measurements obtained from patients who experienced enucleation for unilateral retinoblastoma. Influence factors analyzed included: type of treatment, use of orbital implants, and patient's age at diagnosis. A total of 42 children underwent enucleation with a mean follow-up period of 4.8 years. For 28 patients, treatment included enucleation alone, 14 patients received enucleation plus radiation therapy. Thirty patients kept orbital implants long term. The mean orbital volume asymmetry for treated versus contralateral orbits was 16.8%. Mean asymmetry in orbital volume was greater for patients who underwent enucleation combined to radiation therapy (23.7% vs. 13.3%, P=0.05) and for patients without long-term maintenance of the prosthetic implants (29.3% vs. 11.8%, P<0.01). In conclusion, orbital volume is abnormally affected in children after enucleation of 1 eye for the treatment of retinoblastoma, and computed tomography can precisely quantify the asymmetry that develops. Orbital implants improve volumetric growth after enucleation, with 2-fold greater orbital asymmetry achieved without an implant.

Guidelines for imaging retinoblastoma: imaging principles and MRI standardization

Retinoblastoma is the most common intraocular tumor in children. The diagnosis is usually established by the ophthalmologist on the basis of fundoscopy and US. Together with US, high-resolution MRI has emerged as an important imaging modality for pretreatment assessment, i.e. for diagnostic confirmation, detection of local tumor extent, detection of associated developmental malformation of the brain and detection of associated intracranial primitive neuroectodermal tumor (trilateral retinoblastoma). Minimum requirements for pretreatment diagnostic evaluation of retinoblastoma or mimicking lesions are presented, based on consensus among members of the European Retinoblastoma Imaging Collaboration (ERIC). The most appropriate techniques for imaging in a child with leukocoria are reviewed. CT is no longer recommended. Implementation of a standardized MRI protocol for retinoblastoma in clinical practice may benefit children worldwide, especially those with hereditary retinoblastoma, since a decreased use of CT reduces the exposure to ionizing radiation.

A study of pathologic risk factors in postchemoreduced, enucleated specimens of advanced retinoblastomas in a developing country

CONTEXT

Advanced cases of retinoblastoma are treated with chemoreduction followed by enucleation. Further adjuvant therapy is recommended in patients with known pathologic risk factors (PRFs).

OBJECTIVES

To determine the PRFs in enucleated specimens after chemoreduction and their association for adverse events of recurrence, metastasis, or death.

DESIGN

This was a retrospective study of 77 enucleation specimens from patients treated between January 2000 and September 2008 with prior chemoreduction that were accessioned in the pathology department of a tertiary referral cancer center with an average follow-up of 24 months. Various PRFs were noted and their association with the development of an adverse event was recorded.

RESULTS

Of 77 patients, (male to female ratio, 51∶26), the incidence of overall PRF was 51.9%, and retrolaminar optic nerve invasion (32.5%), optic nerve cut margin (12.9%), massive choroidal invasion (26%), scleral invasion (23.4%), vitreous seedings (44.2%), and anterior segment invasion (20.8%). Undifferentiated tumor (>60%) was seen in 60.3% of cases (41 of 68 patients with differentiation available). Adverse event occurred in 18 of 72 patients with available follow-up (25%). Retrolaminar optic nerve invasion, optic nerve cut margin involvement, and scleral invasion were independent prognostic factors predicting the occurrence of an adverse event. Undifferentiated tumor (>60%) was a significant risk factor in univariate analysis, which is the unique feature in this study.

CONCLUSIONS

Classic PRF with the addition of a predominant presence from the undifferentiated component were associated with adverse outcomes in retinoblastoma treated with anterior chemotherapy. The latter may represent chemoresistant clones and more intensive adjuvant chemotherapy may be warranted in these patients.

Retinoblastoma: Recent trends A mini review based on published literature

Retinoblastoma (RB) is the most common intraocular malignancy in children. Recently, there have been significant advances made in the molecular pathology and the management of the disease. Last decade has witnessed better understanding of the genetics of RB, the discovery of new tumor markers expressed by the RB tumors, the identification of high-risk histopathological factors following enucleation, and newer methods of treatment including periocular chemotherapy and superselective intraarterial chemotherapy. All these advances have translated in improved survival rates for the affected children, improved rates of eye salvage, and improved visual outcomes. This article briefly reviews these advances.Method of Literature Search: Literature on the Medline database was searched using the PubMed interface. The search strategy included MeSH and natural language terms using the keywords mentioned. Reference lists in retrieved articles and textbooks were also searched for relevant references.

Strategies to manage retinoblastoma in developing countries

Survival of retinoblastoma is >90% in developed countries but there are significant differences with developing countries in stage at presentation, available treatment options, family compliance, and survival. In low-income countries (LICs), children present with advanced disease, and the reasons are socioeconomic and cultural. In middle-income countries (MICs), survival rates are better (>70%), but there is a high prevalence of microscopically disseminated extraocular disease. Programs for eye preservation have been developed, but toxicity-related mortality is higher. Although effective treatment of microscopically extraocular disease improved the outcome, worldwide survival will be increased only by earlier diagnosis and better treatment adherence.

Results of a prospective study for the treatment of unilateral retinoblastoma

BACKGROUND

Few prospective studies about the management of unilateral retinoblastoma with pathology risk factors (PRFs) have been published.

METHODS

Patients (n = 114) were divided into four groups: Group 1 (initial chemoreduction) (n = 17). Groups 2 and 3, included patients initially enucleated with no, or lower risk PRFs: (n = 65) and with higher risk PRFs (n = 30), respectively. The later included postlaminar optic nerve involvement (PLONI) (n = 23), tumor at resection margin of optic nerve (n = 5) or isolated scleral invasion (n = 2). Group 3 received adjuvant chemotherapy including a total eight cycles of carboplatin and etoposide, alternating with cyclophosphamide, idarubicin, and vincristine. Orbital radiotherapy (45 Gy) was given to patients with invasion to the resection margin. Group 4 included patients with metastatic disease (n = 2). They were given neoadjuvant therapy followed by surgery and high-dose chemotherapy and autologous stem cell rescue.

RESULTS

Five-year event-free survival is 0.94 (1 for Group 1, 0.94 for Group 2, 0.96 for Group 3, and 0 for Group 4). Events included. Group 2: Systemic relapse (n = 2) and combined orbital and CNS relapse (n = 1). Relapsing patients had PLONI (n = 2) and isolated focal choroidal invasion (n = 1). Group 3: CNS relapse (n = 1) in a patient with tumor at the resection margin of optic nerve. Group 4: CNS relapse (n = 2). Only one relapsed patient survived. Eight of 17 eyes treated conservatively were preserved.

CONCLUSIONS

The survival of patients with unilateral retinoblastoma was excellent and 60% were spared from adjuvant treatment. Our intensive regimen was likely to be effective for prevention of metastasis in patients with higher risk PRFs.

High-dose chemotherapy with autologous hematopoietic stem cell rescue for stage 4B retinoblastoma

BACKGROUND

Stage 4b retinoblastoma (central nervous system metastatic disease) has been lethal in virtually all cases reported. Here we describe a series of eight patients treated with intensive chemotherapy, defined as the intention to include high-dose chemotherapy with autologous hematopoietic stem cell rescue.

PROCEDURE

Induction chemotherapy included cyclophosphamide and/or carboplatin with a topoisomerase inhibitor. High-dose chemotherapy regimens were carboplatin and thiotepa with or without etoposide (n = 3) or carboplatin, etoposide, and cyclophosphamide (n = 2).

RESULTS

Seven patients had leptomeningeal disease and one patient had only direct extension to the CNS via the optic nerve. Three patients had stage 4b disease at the time of original diagnosis of the intra-ocular retinoblastoma; five had later onset at a median of 12 months (range 3-69 months). One patient died of toxicity (septicemia and multi-organ system failure) during induction and two had disease progression prior to high-dose chemotherapy. Five patients received high-dose chemotherapy at a median of 6 months (range 4-6) post-diagnosis of stage 4b disease. Two patients survive event-free at 40 and 101 months; one was irradiated following recovery from the high-dose chemotherapy.

CONCLUSIONS

Intensive multimodality therapy may be beneficial for some patients with stage 4b retinoblastoma. Longer follow-up will determine whether it has been curative.

Contrast-enhancement of the anterior eye segment in patients with retinoblastoma: correlation between clinical, MR imaging, and histopathologic findings

BACKGROUND AND PURPOSE

AES contrast-enhancement is recognized in a substantial number of retinoblastoma-affected eyes. We retrospectively investigated the histopathologic basis of AES contrast-enhancement on MR images in retinoblastoma.

MATERIALS AND METHODS

Pretreatment contrast-enhanced MR images were obtained from 42 children with retinoblastoma. Forty-two enucleated eyes were included in this study, AES enhancement was evaluated by using a 3-point score, and these data were correlated with clinical, MR imaging, and histopathologic findings. Additionally, 14 specimens were immunohistochemically analyzed for CD31, VEGF, and Flt-1 expression. Statistical correlations with AES enhancement were assessed by using a linear-by-linear association test and univariate and multivariate ordinal regressions.

RESULTS

The degree of abnormal AES enhancement was moderate in 15 (36%) eyes and strong in 14 (33%) eyes, whereas 13 (31%) eyes showed normal AES enhancement. In multivariate analysis, the degree of AES enhancement showed statistically significant correlations with iris surface-vessel count (P = .05) and optic nerve invasion (P = .04) in the enucleated eye and with tumor volume (P = .02) as detected on MR imaging. No significant associations between AES enhancement and VEGF expression in the iris were observed. Flt-1 (P = .04) staining in iris stroma and IA as detected with CD31 staining (P = .009) both yielded a statistically significant positive correlation with abnormal AES enhancement.

CONCLUSIONS

The degree of abnormal AES enhancement on MR imaging in retinoblastoma reflects angiogenesis in the iris. AES enhancement is also a hallmark of advanced retinoblastoma because its degree correlates with tumor volume and optic nerve invasion.

Proceedings of the consensus meetings from the International Retinoblastoma Staging Working Group on the pathology guidelines for the examination of enucleated eyes and evaluation of prognostic risk factors in retinoblastoma

Retinoblastoma is the most common intraocular malignant childhood tumor in need of prospective clinical trials to address important unanswered questions about biology, treatment, and prognostic factors. Currently, there is controversy about the definitions for choroidal invasion and an inconsistency in the handling of eyes with retinoblastoma. The International Retinoblastoma Staging Working Group (IRSWG) composed of 58 participants from 24 countries on 4 continents had a series of Internet meetings to discuss the staging and tissue handling guidelines to reach consensus for adequate processing, establishing definitions of histopathologic risk factors, and reporting of enucleated eyes with retinoblastoma to serve as the basis for clinical trials and studies to validate the proposed criteria. The meetings were facilitated by the International Outreach Program of the St. Jude Children's Research Hospital through Cure4Kids. The retinoblastoma guidelines from the Children's Oncology Group, the French Society for Pediatric Cancers, the Association of Directors of Anatomic and Surgical Pathology, and some published data were the basis for this consensus document. Discussions of the feasibility, practicality, and efficacy of the guidelines and criteria resulted in this report. The consensus definitions reached included definition of massive choroidal invasion stated as a maximum diameter of invasive tumor focus of 3 mm or more that may reach the scleral tissue. Focal choroidal invasion is defined as a tumor focus of less than 3 mm and not reaching the sclera. Optic nerve invasion is classified as prelaminar, laminar, retrolaminar, or tumor at surgical margin, and the measurement of the depth of invasion should also be recorded. These guidelines also address handling of the enucleated eye with retinoblastoma in an efficient, practical, and feasible manner for a meaningful diagnosis. The consensus criteria reached by the IRSWG should be validated through prospective clinical trials and studies.

Frontiers in the management of retinoblastoma

PURPOSE

To provide an overview of the current clinical management of retinoblastoma by discussing the trends in the categorization, treatment, and recent advances in molecular diagnostics as well as therapy for retinoblastoma.

DESIGN

Literature review and commentary.

METHODS

Selected articles from the medical literature and the authors' clinical and research experience were reviewed critically.

RESULTS

Retinoblastoma has evolved from a deadly childhood cancer to a largely curable cancer within the past 40 years. Current treatment strategies aim to salvage the eye and provide the best visual outcome possible. Using the international classification system to stratify intraocular retinoblastoma into treatment groups, the multicenter Children's Oncology Group treatment protocols use 2- to 3-drug chemoreduction with focal consolidative therapy for most categories of disease. Furthermore, collaborative efforts are being directed toward a better understanding of genotype-phenotype relationships in retinoblastoma that will be useful in the multidisciplinary management of this disease. Molecular targeting therapy is emerging as a potential strategy to individualize therapy. Finally, improvements in local drug delivery methods and vehicles are providing solutions for the problem of systemic toxicity from existing chemotherapy regimens.

CONCLUSIONS

The management of retinoblastoma has become a prototype for other ophthalmic diseases and systemic cancers in which genetic information and molecular targets are being used to design more elegant treatment strategies.

Predictive factors of invasion in eyes with retinoblastoma enucleated after eye salvage treatments

BACKGROUND

The impact of chemotherapy, focal therapies, radiation and co-existing ocular morbidities on histology of eyes with retinoblastoma enucleated following chemoreduction is not well known.

PROCEDURE

Twenty-five eyes (23 patients) with retinoblastoma enucleated after failing eye-salvage therapy were evaluated. Reasons for enucleation (tumor progression, subretinal or vitreous seeds) and co-morbid conditions (neovascular glaucoma, cataract, vitreous hemorrhage and retinal detachment) were documented. All specimens were reviewed for evidence of ciliary body, choroidal, optic nerve, and scleral invasion.

RESULTS

The median age at diagnosis was 14 months (range, 1-37 months). Twenty eyes were classified as Reese-Ellsworth Group IV-V at diagnosis. Twenty-four eyes had recurrent disease at enucleation; one eye was enucleated for neovascular glaucoma and vitreous hemorrhage. Co-existing ocular morbidities at enucleation included vitreous hemorrhage (n = 6), retinal detachment (n = 9), neovascular glaucoma (n = 9) and cataracts (n = 3). Histologic findings included choroidal invasion (n = 7), ciliary body invasion (n = 4), optic nerve invasion (n = 6) and scleral invasion (n = 3). The median time from diagnosis to enucleation was 11 months. Co-existing retinal detachment and vitreous hemorrhage significantly increased the likelihood of optic nerve invasion (P = 0.014 and P = 0.011, respectively). Prolonged time to enucleation was significantly associated with the likelihood of choroidal (P = 0.010) and ciliary body (P = 0.021) invasion as well as invasion of multiple sites.

CONCLUSION

In eyes with retinoblastoma enucleated after chemoreduction, co-existing ocular morbidities and time to enucleation are predictive of extra-retinal extension.

Persistence of retinal function after selective ophthalmic artery chemotherapy infusion for retinoblastoma

PURPOSE

To assess potential retinal viability by electroretinography following selective ophthalmic artery chemotherapy infusion for retinoblastoma.

METHODS

Uncontrolled prospective case series. Patients with advanced retinoblastoma were offered elective ophthalmic artery chemotherapy infusion treatment under an IRB-approved protocol as an alternative to enucleation. The ophthalmic artery was cannulated under fluoroscopic control, and chemotherapeutic agents (melphalan and occasionally carboplatin) were directly infused at doses resulting in very high local tissue concentrations, but low systemic drug levels. Eyes were examined under anesthesia at 1-month intervals, and re-treated as indicated, up to a maximum of six infusions. Electroretinograms were obtained during examination under anesthesia, using ERG-jet contact lens electrodes and a hand-held mini-ganzfeld stimulator. The ERG protocol was similar to ISCEV standards except for briefer adaptation times as necessary to reduce the total anesthesia duration.

RESULTS

We report initial results in the first ten patients attempted. Nine eyes were successfully cannulated and perfused. ERG data for these nine patients are reported. [Clinical results have been published elsewhere.] Follow up ranged from 3 to 14 months. Extensive, often total, retinal detachments were present in many of the treated eyes. While regression of tumor mass and vitreous seeds was observed in nearly all the patients, retinal detachment occasionally persisted. ERG responses were extinguished in these eyes. Eyes with largely attached retinas, notwithstanding the presence of large tumors at baseline, remained free of detachment after treatment. Normal or near-normal ERGs in these eyes were repeatedly obtained. Recovery of ERG amplitudes was observed in three patients following treatment.

CONCLUSIONS

Retinal function can persist and even recover following selective ophthalmic artery chemotherapy infusion for retinoblastoma. Further work is indicated to determine optimal dosing regimens, maximal tolerated dosage, and subsequent visual function in these patients.