Trilateral retinoblastoma: neuroimaging characteristics and value of routine brain screening on admission

Diagnostic Imaging for Retinoblastoma Cancer Staging: Guide for Providing Essential Insights for Ophthalmologists and Oncologists

Retinoblastoma is the most common cause of all intraocular pediatric malignancies. It is caused by the loss of RB1 tumor suppressor gene function, although some tumors occur due to MYCN oncogene amplification with normal RB1 genes. Nearly half of all retinoblastomas occur due to a hereditary germline RB1 pathogenic variant, most of which manifest with bilateral tumors. This germline RB1 mutation also predisposes to intracranial midline embryonal tumors. Accurate staging of retinoblastoma is crucial in providing optimal vision-, eye-, and life-saving treatment. The AJCC Cancer Staging Manual has undergone significant changes, resulting in a universally accepted system with a multidisciplinary approach for managing retinoblastoma. The authors discuss the role of MRI and other diagnostic imaging techniques in the pretreatment assessment and staging of retinoblastoma. A thorough overview of the prevailing imaging standards and evidence-based perspectives on the benefits and drawbacks of these techniques is provided. Published under a CC BY 4.0 license. Test Your Knowledge questions for this article are available in the supplemental material.

Subsequent Malignant Neoplasms in Retinoblastoma Survivors

Retinoblastoma (Rb) is a pediatric malignant eye tumor. Subsequent malignant neoplasms (SMNs) and trilateral Rb (TRb) are the leading cause of death in heritable Rb patients in developed countries. The high rate of SMNs in heritable Rb patients is attributed to the presence of a mutation in the RB1 tumor suppressor gene. In addition, Rb therapy choices also influence SMN incidence in this patient group. The incidence rates and age of occurrence for the most frequent SMNs and TRb will be discussed. In addition, the impact of genetic predisposition and Rb treatments on the development of SMNs will be evaluated. Furthermore, screening and other prevention methods will be reviewed.

Clinical Features and Survival of Chinese Children With Trilateral Retinoblastoma During 2006-2019: A Retrospective Multicenter Study

PURPOSE

To summarize the clinical features and survival of Chinese patients with trilateral retinoblastoma (TRb), which may help guide early diagnosis and more effective treatments.

DESIGN

Retrospective case series.

METHODS

Clinical records of patients with TRb were reviewed to identify clinical characteristics and outcomes. TRb was diagnosed mainly based on imaging findings of an enlarged solid pineal or sellar mass. Mutation screening was performed using peripheral blood leucocyte DNA from 3 patients.

RESULTS

Fourteen patients with TRb were identified from among 3,789 patients with retinoblastoma (0.4%). Thirteen patients had bilateral retinoblastoma and 1 patient had unilateral disease. The follow-up results revealed that 2 patients survived, 3 patients were lost to follow-up, and 9 patients died. The mean overall survival was 9.8 months (95% confidence interval: 2.3-17.2), and the 2-year survival rate was 18.8% (95% confidence interval: 2.9-45.1) based on Kaplan-Meier estimates. Cox regression multivariate analysis showed metastasis at TRb diagnosis was an independent variable of overall survival (hazard ratio: 15.8; 95% confidence interval: 0.24-5.29; P = .032). Three germline mutations in the RB1 gene were detected via next-generation sequencing.

CONCLUSIONS

TRb is a rare intracranial mid-line neuroblastic disease. Increased awareness of this disease could guide early detection, which has been associated with improved outcomes.

Genetic syndromes predisposing to pediatric brain tumors

The application of high-throughput sequencing approaches including paired tumor/normal sampling with therapeutic intent has demonstrated that 8%-19% of pediatric CNS tumor patients harbor a germline alteration in a classical tumor predisposition gene (NF1, P53). In addition, large-scale germline sequencing studies in unselected cohorts of pediatric neuro-oncology patients have demonstrated novel candidate tumor predisposition genes (ELP1 alterations in sonic hedgehog medulloblastoma). Therefore, the possibility of an underlying tumor predisposition syndrome (TPS) should be considered in all pediatric patients diagnosed with a CNS tumor which carries critical implications including accurate prognostication, selection of optimal therapy, screening, risk reduction, and family planning. The Pediatric Cancer Working Group of the American Association for Cancer Research (AACR) recently published consensus screening recommendations for children with the most common TPS. In this review, we provide an overview of the most relevant as well as recently identified TPS associated with the most frequently encountered pediatric CNS tumors with an emphasis on pathogenesis, genetic testing, clinical features, and treatment implications.

Retinoblastoma: What the Neuroradiologist Needs to Know

Retinoblastoma is the most common primary intraocular tumor of childhood. Accurate diagnosis at an early stage is important to maximize patient survival, globe salvage, and visual acuity. Management of retinoblastoma is individualized based on the presenting clinical and imaging features of the tumor, and a multidisciplinary team is required to optimize patient outcomes. The neuroradiologist is a key member of the retinoblastoma care team and should be familiar with characteristic diagnostic and prognostic imaging features of this disease. Furthermore, with the adoption of intra-arterial chemotherapy as a standard of care option for globe salvage therapy in many centers, the interventional neuroradiologist may play an active role in retinoblastoma treatment. In this review, we discuss the clinical presentation of retinoblastoma, ophthalmic imaging modalities, neuroradiology imaging features, and current treatment options.

MRI-based diagnosis and treatment of pediatric brain tumors: is tissue sample always needed?

Traditional management of newly diagnosed pediatric brain tumors (PBTs) consists of cranial imaging, typically magnetic resonance imaging (MRI), and is frequently followed by tissue diagnosis, through either surgical biopsy or tumor resection. Therapy regimes are typically dependent on histological diagnosis. To date, many treatment regimens are based on molecular biology. The scope of this article is to discuss the role of diagnosis and further treatment of PBTs based solely on MRI features, in light of the latest treatment protocols. Typical MRI findings and indications for surgical biopsy of these lesions are described.

A Potential Role For Apparent Diffusion Coefficient in the Diagnosis of Trilateral Retinoblastoma

We attempted to investigate the potential role for apparent diffusion coefficient (ADC) to diagnose trilateral retinoblastoma (TRb) by retrospectively reviewing brain magnetic resonance images of retinoblastoma patients. Observations: The median ADC measured 620.95 for TRb (n=6) and 1238.5 for normal pineal gland in bilateral retinoblastoma (n=8). Monitoring ADC trends aided in establishing the appropriate diagnoses in 3 patients (2 TRb, 1 benign pineal cyst). Conclusions: Our results provide baseline reference data and describe the importance of downward trending ADC which should prompt consideration of TRb. Unchanged high/nonrestricted values (>1000) may distinguish those with benign pineal tissue and obviate invasive neurosurgical procedures.

Screening for Pineal Trilateral Retinoblastoma Revisited: A Meta-analysis

TOPIC

To determine the age up to which children are at risk of trilateral retinoblastoma (TRb) developing, whether its onset is linked to the age at which intraocular retinoblastomas develop, and the lead time from a detectable pineal TRb to symptoms.

CLINICAL RELEVANCE

Approximately 45% of patients with retinoblastoma-those with a germline RB1 pathogenic variant-are at risk of pineal TRb developing. Early detection and treatment are essential for survival. Current evidence is unclear regarding the usefulness of screening for pineal TRb and, if useful, the age up to which screening should be continued.

METHODS

We conducted a study according to the Meta-analysis of Observational Studies in Epidemiology guidelines for reporting meta-analyses of observational studies. We searched PubMed and Embase between January 1, 1966, and February 27, 2019, for published literature. We considered articles reporting patients with TRb with survival and follow-up data. Inclusion of articles was performed separately and independently by 2 authors, and 2 authors also independently extracted the relevant data. They resolved discrepancies by consensus.

RESULTS

One hundred thirty-eight patients with pineal TRb were included. Of 22 asymptomatic patients, 21 (95%) were diagnosed before the age of 40 months (median, 16 months; interquartile range, 9-29 months). Age at diagnosis of pineal TRb in patients diagnosed with retinoblastoma at 6 months or younger versus older than 6 months were comparable (P = 0.44), suggesting independence between the ages at diagnosis of intraocular retinoblastoma and pineal TRb. The laterality of intraocular retinoblastoma and its treatment were not associated with the age at which pineal TRb was diagnosed. The lead time from asymptomatic to symptomatic pineal TRb was approximately 1 year. By performing a screening magnetic resonance imaging scan every 6 months after the diagnosis of heritable retinoblastoma (median age, 6 months) until 36 months of age, at least 311 and 776 scans would be required to detect 1 case of asymptomatic pineal TRb and to save a single life, respectively.

CONCLUSIONS

Patients with retinoblastoma are at risk of pineal TRb developing for a shorter period than previously assumed, and the age at diagnosis of pineal TRb is independent of the age at diagnosis of retinoblastoma. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) level of evidence for these conclusions remains low.

Drug Repurposing for Retinoblastoma: Recent Advances

Retinoblastoma is the intraocular malignancy that occurs during early childhood. The current standard of care includes chemotherapy followed by focal consolidative therapies, and enucleation. Unfortunately, these are associated with many side and late effects. New drugs and/or drug combinations need to be developed for safe and effective treatment. This compelling need stimulated efforts to explore drug repurposing for retinoblastoma. While conventional drug development is a lengthy and expensive process, drug repurposing is a faster, alternate approach, where an existing drug, not meant for treating cancer, can be repurposed to treat retinoblastoma. The present article reviews various attempts to test drugs approved for different purposes such as calcium channels blockers, non-steroidal antiinflammatory drugs, cardenolides, antidiabetic, antibiotics and antimalarial for treating retinoblastoma. It also discusses other promising candidates that could be explored for repurposing for retinoblastoma.

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.

Neoplastic Meningitis: A Study from a Tertiary Care Hospital from Coastal India

Introduction:

Neoplastic involvement of cerebrospinal fluid (CSF) secondary to known or unknown primaries elsewhere is a poor prognostic factor and is equivalent to stage IV disease.

Aim:

The aim of the study is to analyse the cytological features of neoplastic meningitis in a tertiary care center.

Materials and Methods:

A retrospective study of 400 consecutive CSF samples was done in the cytology laboratory of our hospital. The fluid obtained by spinal tap was sent for microbiological, biochemical and cytological evaluation. Smears that showed the presence of malignant cells were included in this study.

Results:

Out of 400 cases, 36 (9%) showed neoplastic meningitis. Of which, 13 cases (36%) revealed leukemic infiltration, 2 (6%) lymphomatous infiltration and 21 (58%) carcinomatous meningitis. The leukemia cases included seven cases of acute lymphoblastic leukemia and six cases of acute myeloid leukemia. Among the carcinomatous meningitis cases, eight were metastasis from carcinoma breast, six from lung carcinoma and one each from malignancies of gallbladder, stomach and retinoblastoma. Four cases were metastatic adenocarcinoma from unknown primary. Pleocytosis was a significant finding seen in 58% cases (n = 21). Elevated protein and hypoglychorrhachia was noted in 68% cases (n = 18).

Conclusion:

A combined diagnostic approach including biochemical, microbiological and pathological evaluation was useful in eliminating infectious meningitis and confirming neoplastic meningitis in these cases. Cytology should be performed on cerebrospinal specimens from all patients with known or suspected malignancy with meningismus. Detection of malignant cells on cytological examination of CSF is the diagnostic gold standard for neoplastic meningitis.

Blood Flow in Monocular Retinoblastoma Assessed by Color Doppler and Correlations With High-Risk Pathologic Features

Purpose

To use color Doppler to analyze blood flow in the retrobulbar central retinal artery (CRA) and central retinal vein (CRV) in monocular retinoblastoma.

Methods

This prospective study included patients with group D and E retinoblastomas managed with only enucleation. Peak blood velocities were assessed in the CRA and CRV of tumor-containing eyes (CRAv and CRVv, respectively). The resistivity index in the CRA (RIa) and pulse index in the CRV (PIv) were calculated and related to optic nerve invasion (ONi), choroid invasion (mCHi), and tumor volume. RIa and PIv were also calculated for healthy eyes.

Results

In total, 25 patients with a mean age of 30.8-months old were included. The means (SD) for CRAv, CRVv, RIa, and PIv were 26.94 (12.32) cm/s, 16.2 (9.56) cm/s, 0.88 (0.12) and 0.79 (0.29), respectively. Tumor volume was significantly correlated with CRAv (P = 0.025) and RIa (P = 0.032). ONi was present in 19 eyes and correlated with a smaller PIv (P < 0.001). A PIv less than 0.935 had a sensitivity of 89.5% and specificity of 83.3% for predicting ONi. mCHi was not correlated with flow values. Healthy eyes had a significantly lower RIa (P < 0.001) and lower PIv than eyes with (P = 0.009) and without (P < 0.001) ONi.

Conclusions

In advanced-stage monocular retinoblastoma, tumor volume was directly correlated with CRAv and RIa, and lower PIv was correlated with optic nerve invasion when a predictive cut-off value of less than 0.935 was applied. Comparisons with healthy eyes showed that tumor-containing eyes were associated with higher RIa and PIv values.

Trilateral retinoblastoma: A systematic review of 211 cases

We conducted a systematic review of 72 studies to characterize trilateral retinoblastomas. Kaplan-Meier analysis was used to estimate survival, and statistical significance was assessed by using a log-rank test. We analyzed 211 cases of trilateral retinoblastomas. The average age of onset of retinoblastoma was 0.79 ± 1.38 years, and the average latency period between the onset of retinoblastomas and trilateral retinoblastomas was 1.49 ± 1.76 years. The brain tumors were found before the retinoblastoma diagnosis in 6 cases (3.1%), concurrently in 61 cases (32.1%), and after the retinoblastoma diagnosis in 123 cases (64.7%). Pineal tumors were found in 155 cases (73.4%) and sellar tumors in 46 cases (21.8%). The overall median survival was 10.3 months (95% CI, 8.5-13) and the 5-year survival rate was 15.7%. Central nervous system symptoms were variable and associated with shorter survival in univariate and multivariate analyses. The survival time in patients who received high-dose chemotherapy with stem cell transplant was significantly longer (p = 0.0067) than that of with or without conventional chemotherapy. Twelve long-term survivors were reported, and of these, six patients were treated with high-dose chemotherapy with stem cell transplant and six patients were treated with conventional chemotherapy. It is important that survivors continue to undergo regular medical surveillance in order to detect trilateral retinoblastoma at a potentially curative stage. Trilateral retinoblastoma patients with an irradiation history had shorter survival than those without irradiation history for retinoblastoma. High-dose chemotherapy should be considered as a potential treatment option for trilateral retinoblastomas.

Pineal cysts-A benign association with familial retinoblastoma

Patients with familial/heritable retinoblastoma (RB) are at increased risk of developing second malignancies throughout life, including a pineoblastoma (trilateral RB [TRB]) in early childhood. Current guidelines recommend regular surveillance brain imaging for those with heritable RB until 5 years of age. The presence of pineal cysts has been reported in patients with RB. Pineal cysts are thought to arise due to focal degeneration of the pineal gland and can be found incidentally. The finding of pineal abnormalities including cysts in children with RB on imaging is disconcerting, as it raises the possibility of an underlying malignancy, specifically a pinealoblastoma. The authors reviewed the imaging findings and clinical significance of pineal cysts in 69 patients diagnosed with RB at our center between December 1999 and November 2015. Twenty-six patients had pineal cysts found on brain magnetic resonance imaging (MRI) scans performed either at diagnosis or follow-up. Thirty-eight of 69 patients had underlying heritable RB. Nineteen of 38 familial RB patients had a pineal cyst compared with 3 out of 26 with sporadic RB (P = .004). In the majority, the imaging characteristics and size of the cysts remained stable or resolved. In this cohort, pineal cysts were detected at significantly increased frequency in heritable RB. This may be a benign association or may reflect abnormal underlying biology of pineal tissue in individuals highly susceptible to malignancy. Imaging characteristics can be helpful in distinguishing between benign and malignant lesions. The presence of a pineal cyst in patients with unilateral disease may be a useful indicator of underlying heritable RB.

MRI-based assessment of the pineal gland in a large population of children aged 0-5 years and comparison with pineoblastoma: part II, the cystic gland

Introduction

Pineal cysts are a common incidental finding on brain MRI with resulting difficulties in differentiation between normal glands and pineal pathologies. The aim of this study was to assess the size and morphology of the cystic pineal gland in children (0–5 years) and compare the findings with published pineoblastoma cases.

Methods

In this retrospective multicenter study, 257 MR examinations (232 children, 0–5 years) were evaluated regarding pineal gland size (width, height, planimetric area, maximal cyst(s) size) and morphology. We performed linear regression analysis with 99 % prediction intervals of gland size versus age for the size parameters. Results were compared with a recent meta-analysis of pineoblastoma by de Jong et al.

Results

Follow-up was available in 25 children showing stable cystic findings in 48 %, cyst size increase in 36 %, and decrease in 16 %. Linear regression analysis gave 99 % upper prediction bounds of 10.8 mm, 10.9 mm, 7.7 mm and 66.9 mm², respectively, for cyst size, width, height, and area. The slopes (size increase per month) of each parameter were 0.030, 0.046, 0.021, and 0.25, respectively. Most of the pineoblastomas showed a size larger than the 99 % upper prediction margin, but with considerable overlap between the groups.

Conclusion

We presented age-adapted normal values for size and morphology of the cystic pineal gland in children aged 0 to 5 years. Analysis of size is helpful in discriminating normal glands from cystic pineal pathologies such as pineoblastoma. We also presented guidelines for the approach of a solid or cystic pineal gland in hereditary retinoblastoma patients.

Electronic supplementary material

The online version of this article (doi:10.1007/s00234-016-1683-0) contains supplementary material, which is available to authorized users.

MRI-based assessment of the pineal gland in a large population of children aged 0-5 years and comparison with pineoblastoma: part I, the solid gland

Introduction

Differentiation between normal solid (non-cystic) pineal glands and pineal pathologies on brain MRI is difficult. The aim of this study was to assess the size of the solid pineal gland in children (0–5 years) and compare the findings with published pineoblastoma cases.

Methods

We retrospectively analyzed the size (width, height, planimetric area) of solid pineal glands in 184 non-retinoblastoma patients (73 female, 111 male) aged 0–5 years on MRI. The effect of age and gender on gland size was evaluated. Linear regression analysis was performed to analyze the relation between size and age. Ninety-nine percent prediction intervals around the mean were added to construct a normal size range per age, with the upper bound of the predictive interval as the parameter of interest as a cutoff for normalcy.

Results

There was no significant interaction of gender and age for all the three pineal gland parameters (width, height, and area). Linear regression analysis gave 99 % upper prediction bounds of 7.9, 4.8, and 25.4 mm², respectively, for width, height, and area. The slopes (size increase per month) of each parameter were 0.046, 0.023, and 0.202, respectively. Ninety-three percent (95 % CI 66–100 %) of asymptomatic solid pineoblastomas were larger in size than the 99 % upper bound.

Conclusion

This study establishes norms for solid pineal gland size in non-retinoblastoma children aged 0–5 years. Knowledge of the size of the normal pineal gland is helpful for detection of pineal gland abnormalities, particularly pineoblastoma.

Electronic supplementary material

The online version of this article (doi:10.1007/s00234-016-1684-z) contains supplementary material, which is available to authorized users.

Blood flow velocity in monocular retinoblastoma assessed by color Doppler

OBJECTIVE

To analyze the flow of retrobulbar vessels in retinoblastoma by color Doppler imaging.

METHODS

A prospective study of monocular retinoblastoma treated by enucleation between 2010 and 2014. The examination comprised fundoscopy, magnetic resonance imaging, ultrasonography and color Doppler imaging. The peak blood velocities in the central retinal artery and central retinal vein of tumor-containing eyes (tuCRAv and tuCRVv, respectively) were assessed. The velocities were compared with those for normal eyes (nlCRAv and nlCRVv) and correlated with clinical and pathological findings. Tumor dimensions in the pathological sections were compared with those in magnetic resonance imaging and ultrasonography and were correlated with tuCRAv and tuCRVv. In tumor-containing eyes, the resistivity index in the central retinal artery and the pulse index in the central retinal vein were studied in relation to all variables.

RESULTS

Eighteen patients were included. Comparisons between tuCRAv and nlCRAv and between tuCRVv and nlCRVv revealed higher velocities in tumor-containing eyes (p < 0.001 for both), with a greater effect in the central retinal artery than in the central retinal vein (p = 0.024). Magnetic resonance imaging and ultrasonography measurements were as reliable as pathology assessments (p = 0.675 and p = 0.375, respectively). A positive relationship was found between tuCRAv and the tumor volume (p = 0.027). The pulse index in the central retinal vein was lower in male patients (p = 0.017) and in eyes with optic nerve invasion (p = 0.0088).

CONCLUSIONS

TuCRAv and tuCRVv are higher in tumor-containing eyes than in normal eyes. Magnetic resonance imaging and ultrasonography measurements are reliable. The tumor volume is correlated with a higher tuCRAv and a reduced pulse in the central retinal vein is correlated with male sex and optic nerve invasion.

Trilateral retinoblastoma: a systematic review and meta-analysis

BACKGROUND

About 5% of children with retinoblastoma from germline mutation of the RB1 gene are at risk of developing trilateral retinoblastoma--intraocular retinoblastoma combined with a histologically similar brain tumour, most commonly in the pineal gland. We aimed to provide a systematic overview of published data for trilateral retinoblastoma, and to analyse how survival has changed.

METHODS

We searched Medline and Embase for scientific literature published between Jan 1, 1966, and April 14, 2014, that assessed trilateral retinoblastoma cases. We undertook a meta-analysis of survival with the Kaplan-Meier method and Cox proportional hazards regression, stratified on the basis of the original study, to account for between-study heterogeneity.

FINDINGS

We included 90 studies, with 174 patients with trilateral retinoblastoma. 5-year survival after pineal trilateral retinoblastoma increased from 6% (95% CI 2-15) in patients diagnosed before 1995, to 44% (26-61; p<0·0001) in those diagnosed from 1995 onwards. Before 1995, no patients with non-pineal trilateral retinoblastoma survived, but from 1995 onwards, 5-year survival was 57% (30-77; p=0·035). Hazard ratios (HR) adjusted for the presence of leptomeningeal metastases and trilateral retinoblastoma location, suggested that both conventional (HR 0·059, 95% CI 0·016-0·226; p<0·0001) and high-dose chemotherapy with stem-cell rescue (0·013, 0·002-0·064; p<0·0001) most strongly contributed to this improvement. Absence of leptomeningeal metastases (HR 2·13, 95% CI 0·98-4·60; p=0·055) were associated with improved survival. Non-pineal trilateral retinoblastomas were larger than pineal tumours (median 30 mm [range 6-100] vs 22 mm [7-60]; p=0·012), but both had similar outcomes since 1995.

INTERPRETATION

Our results suggest that improvements in overall survival are attributable to improved chemotherapy regimens and early detection of pineal trilateral retinoblastoma. As such, successful treatment of trilateral retinoblastoma should include screening at least at the time of retinoblastoma diagnosis and chemotherapy, which would preferably be a high-dose regimen with autologous stem-cell rescue.

FUNDING

None.

The management of pineal tumors as a model for a multidisciplinary approach in neuro-oncology

The management of pineal tumors is a model for multidisciplinarity. Apart from an emergency situation that requires immediate shunting of cerebrospinal fluid (CSF), the initial discussion should involve at least a radiologist, a surgeon, a neurologist and an oncologist. The initial decision is whether obtaining a histological proof is obligatory. It depends on age and ethnicity, site (mono- or bifocality), presence of markers in serum as well as CSF, and/or of malignant cells in the CSF. In cases of marker elevation indicating a germ cell tumor, front line chemotherapy can avoid dangerous immediate surgery. When histological proof is required, the extent of surgery should be discussed, aiming either only at obtaining tissue or removal. If a germ cell tumor is detected, treatment will include a cisplatin-containing chemotherapy followed by focal or ventricular irradiation. Tumors of the pineal parenchyma will be treated according to grade, either by surgery alone (pinealocytoma) or chemo-radiotherapy (pinealoblastomas). Similarly, gliomas will be treated depending on their grade with several different possible lines in low grade, and usually radio-chemotherapy in high grade. A careful balance between improved survival rates and decreased long-term side effects will guide the decisions of all these specialists.

[Retinoblastoma: recent advances]

Retinoblastoma is the most common intraocular malignancy of infancy with an incidence of 1/15,000 to 1/20,000 births. Sixty percent of retinoblastomas are unilateral, with a median age at diagnosis of two years, and in most cases are not hereditary. Retinoblastoma is bilateral in 40% of cases, with an earlier median age at diagnosis of one year. All bilateral and multifocal unilateral forms are hereditary and are part of a genetic cancer predisposition syndrome. All children with a bilateral or familial form, and 10 to 15% of children with an unilateral form, constitutionally carry an RB1 gene mutation. The two most frequent symptoms revealing retinoblastoma are leukocoria and strabismus. Diagnosis is made by fundoscopy, with ultrasound and magnetic resonance imaging (MRI) contributing both to diagnosis and assessment of the extension of the disease. Treatment of patients with retinoblastoma must take into account the various aspects of the disease (unilateral/bilateral, size, localization…), the risk to vision and the possible hereditary nature of the disease. The main prognostic aspects are still premature detection and adapted coverage by a multi-disciplinary specialized team. Enucleation is still often necessary in unilateral disease; the decision for adjuvant treatment is taken according to the histological risk factors. The most important recent therapeutic advances concern the conservative treatment which is proposed for at least one of the two eyes in most bilateral cases: laser alone or in combination with chemotherapy, cryotherapy or brachytherapy. Recently, the development of new conservative techniques of treatment, such as intra-arterial selective chemotherapy perfusion, aims at preserving visual function in these children and decreasing the number of enucleations and the need for external beam radiotherapy. The vital prognosis related to retinoblatoma is now excellent in industrialized countries, but long-term survival is still related to the development of secondary tumors, mainly secondary sarcoma. Retinoblastoma requires multi-disciplinary care as well as a long term specialized follow-up. Early counseling of patients and their family concerning the risk of transmission of the disease and the risk of development of secondary tumors is necessary.

Diffusion-weighted imaging to assess treatment response in a child with trilateral retinoblastoma

Trilateral retinoblastoma (TRb) is a rare condition in which children with bilateral retinoblastoma develop primary midline intracranial neuroblastic tumors. The intracranial lesions are difficult to follow after treatment due to residual mass-like enhancement that may represent persistent tumor or treated disease. We highlight a case where close evaluation of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) characteristics accurately depicted the extent of treated disease versus residual tumor after chemotherapy.