Neonatal Retinoblastoma

From 7% to 10% of all retinoblastomas and from 44% to 71% of familial retinoblastomas in developed countries are diagnosed in the neonatal period, usually through pre- or post-natal screening prompted by a positive family history and sometimes serendipitously during screening for retinopathy of prematurity or other reasons. In developing countries, neonatal diagnosis of retinoblastoma has been less common. Neonatal retinoblastoma generally develops from a germline mutation of RB1, the retinoblastoma gene, even when the family history is negative and is thus usually hereditary. At least one-half of infants with neonatal retinoblastoma have unilateral tumors when the diagnosis is made, typically the International Intraocular Retinoblastoma Classification (Murphree) Group B or higher, but most germline mutation carriers will progress to bilateral involvement, typically Group A in the fellow eye. Neonatal leukokoria usually leads to the diagnosis in children without a family history of retinoblastoma, and a Group C tumor or higher is typical in the more advanced involved eye. Almost all infants with neonatal retinoblastoma have at least one eye with a tumor in proximity to the foveola, but the macula of the fellow eye is frequently spared. Consequently, loss of reading vision from both eyes is exceptional. A primary ectopic intracranial neuroblastic tumor known as trilateral retinoblastoma is no more common after neonatal than other retinoblastoma. For many reasons, neonatal retinoblastoma may be a challenge to eradicate, and the early age at diagnosis and relatively small tumors do not guarantee the preservation of both eyes of every involved child. Oncology nurses can be instrumental in contributing to better outcomes by ensuring that hereditary retinoblastoma survivors receive genetic counseling, by referring families of survivors to early screening programs when they are planning for a baby, and by providing psychological and practical support for parents when neonatal retinoblastoma has been diagnosed.

A Case of Anterior Chamber Cholesterolosis Due to Coats' Disease and a Review of Reported Cases

Purpose:

To present the case of an 18 month old boy with Coats' disease who was found to have anterior chamber cholesterolosis.

Methods:

Case presentation and review of reported cases.

Results:

An 18 month old boy presented with unilateral stage 3B Coats' disease without other clinical findings. Two weeks after presentation he returned with xanthocoria due to anterior chamber cholesterolosis. He subsequently developed hyphema, neovascular glaucoma, and was enucleated. His case is compared to all previously reported cases of Coats' disease leading to anterior chamber cholesterolosis.

Conclusion:

The presentation of anterior chamber cholesterolosis in Coats' disease can range from the incidental finding in an asymptomatic patient to acute angle closure glaucoma with pain and acutely decreased vision. Clinicians should be aware of this potential complication of Coats' disease as it denotes a poor visual prognosis.

Hemodynamic and Anatomic Variations Require an Adaptable Approach during Intra-Arterial Chemotherapy for Intraocular Retinoblastoma: Alternative Routes, Strategies, and Follow-Up

BACKGROUND AND PURPOSE

Intra-arterial chemotherapy for retinoblastoma is not always a straightforward procedure, and it may require an adaptable approach. This study illustrates strategies used when the ophthalmic artery is difficult to catheterize or not visible, and it ascertains the effectiveness and safety of these strategies.

MATERIALS AND METHODS

A retrospective study was performed on a series of 108 eyes affected by intraocular retinoblastoma and selected for intra-arterial chemotherapy (follow-up range, 6-82 months). We recognized 3 different patterns of drug delivery: a fixed pattern through the ophthalmic artery, a fixed pattern through branches of the external carotid artery, and a variable pattern through either the ophthalmic or the external carotid artery.

RESULTS

We performed 448 sessions of intra-arterial chemotherapy, 83.70% of them through the ophthalmic artery and 16.29% via the external carotid artery. In 24.52% of eyes, the procedure was performed at least once through branches of the external carotid artery. In 73 eyes, the pattern of drug delivery was fixed through the ophthalmic artery; for 9 eyes, it was fixed through branches of the external carotid artery; and for 17 eyes, the pattern was variable. Statistical analysis did not show any significant difference in the clinical outcome of the eyes (remission versus enucleation) treated with different patterns of drug delivery. Adverse events could not be correlated with any particular pattern.

CONCLUSIONS

Alternative routes of intra-arterial chemotherapy for intraocular retinoblastoma appear in the short term as effective and safe as the traditional drug infusion through the ophthalmic artery.

MRI helps depict clinically undetectable risk factors in advanced stage retinoblastomas

This study compared high-resolution MRI with histology in advanced stage retinoblastomas in which ophthalmoscopy and ultrasonography did not give an exhaustive depiction of the tumour and/or its extension. MRI of orbits and head in 28 retinoblastoma patients (28 eyes) treated with primary enucleation were evaluated. Iris neoangiogenesis, infiltrations of optic nerve, choroid, anterior segment and sclera suspected at MR and histology were compared. Abnormal anterior segment enhancement (AASE) was also correlated with histologically proven infiltrations. Brain images were also evaluated. Significant values were obtained for: prelaminar optic nerve (ON) sensitivity (0.88), positive predictive value (PPV) (0.75) and negative predictive value (NPV) (0.71); post-laminar ON sensitivity (0.50), specificity (0.83), PPV (0.50) and NPV (0.83); overall choroid sensitivity (0.82), and massive choroid NPV (0.69); scleral specificity (1), and NPV (1). AASE correlated with iris neoangiogenesis in 14 out of 19 eyes, and showed significant values for: overall ON PPV (0.65), prelaminar ON sensitivity (0.65), and PPV (0.61), post-laminar ON NPV (0.64); overall choroid sensitivity (0.77), PPV (0.59) and NPV (0.73); scleral NPV (0.83); anterior segment sensitivity (1), and NPV (1). Odds ratios (OR) and accuracy were significant in scleral and prelaminar optic nerve infiltration. Brain examination was unremarkable in all cases. High-resolution MRI may add important findings to clinical evaluation of advanced stage retinoblastomas.

Two masquerade presentations of retinoblastoma

Masquerade syndromes are disorders occurring with intraocular inflammation misdiagnosed as uveitis. The underlying causes may be benign or malignant conditions, and one of the most important diagnoses to take into consideration in children is retinoblastoma. We present two cases with uncertain early misdiagnosis whose definite diagnosis eventually was retinoblastoma.

A 6-year-old boy with Cornelia de Lange syndrome and Coats disease: case report and review of the literature

Cornelia de Lange syndrome (CdLS) can result in multiple congenital abnormalities and numerous ocular findings. We report the case of a 6-year-old boy with history of CdLS who presented with Coats disease. The findings in this case are compared to those found in the two previously reported cases of concomitant CdLS and Coats disease. The low incidence of these two disorders makes it highly unlikely that the connection is random in these 3 cases. The number of patients with both Cornelia de Lange syndrome and Coats disease is likely underestimated due to the difficulty in examining the peripheral retina in this patient population.

Transorbital anastomotic pathways between the external and internal carotid systems in children affected by intraocular retinoblastoma

PURPOSE

It is well known that many anastomoses can join the external carotid system and the ophthalmic artery. However, their frequency has never been reported. Since they can be relevant for interventional radiologists operating in the orbit, we decided to illustrate and determine the frequency of the anastomoses that can be found in children.

METHODS

A retrospective study of 443 angiographic procedures (via ophthalmic artery and/or external carotid artery) carried out on 97 children affected by intraocular retinoblastoma was made to investigate the arterial anatomy of 106 orbits.

RESULTS

Anastomoses were observed in 44.33 % of orbits. However, their true frequency is likely much higher as the rate of visualization increased up to 91.11 % of orbits when the angiographic study was extended to the external carotid artery. In order of frequency we detected the following anastomoses: lacrimal artery-middle meningeal artery, lacrimal artery-anterior deep temporal artery, ophthalmic artery-middle meningeal artery, ophthalmic artery-facial artery, supraorbital artery-superficial temporal artery, supratrochlear artery-superficial temporal artery, supraorbital artery-middle meningeal artery, dorsal nasal artery-infraorbital artery, supraorbital artery-zygomaticoorbital artery, lacrimal artery-zygomaticoorbital artery.

CONCLUSION

When properly searched, anastomoses between the ophthalmic artery and the external carotid artery are almost constant in children. Depending on the clinical scenario, they can represent dangers or valuable alternative routes for collateral circulations and intraarterial chemotherapy.

Identification of Intraorbital Arteries in Pediatric Age by High Resolution Superselective Angiography

PURPOSE

Angiography is a powerful tool to identify intraorbital arteries. However, the incidence by which these vessels can be identified is unknown. Our purpose was to determine such incidence and which angiographic approach is best for the identification of each artery.

METHODS

A retrospective study of 353 angiographic procedures (via ophthalmic artery and/or external carotid artery) carried out on 79 children affected by intraocular retinoblastoma was made to investigate the arterial anatomy in 87 orbits. For each intraorbital artery two parameters were calculated: the angiographic incidence, as the percentage of times a given artery was identified, and the visibility index, as the ratio between the angiographic incidence and the true anatomic incidence.

RESULTS

All collaterals of the ophthalmic artery could be spotted. Most of them were identified with a high angiographic incidence; some of them were less easily identified because too thin or because frequently shielded. The visibility index paralleled the angiographic incidence of most arteries. However, the lacrimal and meningolacrimal arteries had a higher visibility index suggesting that their identification was more frequent than the angiographic incidence alone could suggest. Statistical analysis demonstrated that the lacrimal artery and some muscular branches had higher chances to be identified if the angiography of the ophthalmic artery was accompanied by the study of the external carotid system.

CONCLUSION

This work provides an objective measure of how powerful angiography is to identify intraorbital arteries as well as useful references for professionals who need to operate in the orbit.

Detection of calcifications in retinoblastoma using gradient-echo MR imaging sequences: comparative study between in vivo MR imaging and ex vivo high-resolution CT

BACKGROUND AND PURPOSE

Intratumoral calcifications are very important in the diagnosis of retinoblastoma. Although CT is considered superior in detecting calcification, its ionizing radiation, especially in patients with hereditary retinoblastoma, should be avoided. The purpose of our study was to validate T2*WI for the detection of calcification in retinoblastoma with ex vivo CT as the criterion standard.

MATERIALS AND METHODS

Twenty-two consecutive patients with retinoblastoma (mean age, 21 months; range, 1-71 months) with enucleation as primary treatment were imaged at 1.5T by using a dedicated surface coil. Signal-intensity voids indicating calcification on T2*WI were compared with ex vivo high-resolution CT, and correlation was scored by 2 independent observers as poor, good, or excellent. Other parameters included the shape and location of the signal-intensity voids. In 5 tumors, susceptibility-weighted images were evaluated.

RESULTS

All calcifications visible on high-resolution CT could be matched with signal-intensity voids on T2*WI, and correlation was scored as excellent in 17 (77%) and good in 5 (23%) eyes. In total, 93% (25/27) of the signal-intensity voids inside the tumor correlated with calcifications compared with none (0/8) of the signal-intensity voids outside the tumor. Areas of nodular signal-intensity voids correlated with calcifications in 92% (24/26), and linear signal-intensity voids correlated with hemorrhage in 67% (6/9) of cases. The correlation of signal-intensity voids on SWI was better in 4 of 5 tumors compared with T2*WI.

CONCLUSIONS

Signal-intensity voids on in vivo T2*WI correlate well with calcifications on ex vivo high-resolution CT in retinoblastoma. Gradient-echo sequences may be helpful in the differential diagnosis of retinoblastoma. The combination of funduscopy, sonography, and high-resolution MR imaging with gradient-echo sequences should become the standard diagnostic approach for retinoblastoma.

Assessment of early-stage optic nerve invasion in retinoblastoma using high-resolution 1.5 Tesla MRI with surface coils: a multicentre, prospective accuracy study with histopathological correlation

OBJECTIVES

To assess the accuracy of high-resolution (HR) magnetic resonance imaging (MRI) in diagnosing early-stage optic nerve (ON) invasion in a retinoblastoma cohort.

METHODS

This IRB-approved, prospective multicenter study included 95 patients (55 boys, 40 girls; mean age, 29 months). 1.5-T MRI was performed using surface coils before enucleation, including spin-echo unenhanced and contrast-enhanced (CE) T1-weighted sequences (slice thickness, 2 mm; pixel size <0.3 × 0.3 mm(2)). Images were read by five neuroradiologists blinded to histopathologic findings. ROC curves were constructed with AUC assessment using a bootstrap method.

RESULTS

Histopathology identified 41 eyes without ON invasion and 25 with prelaminar, 18 with intralaminar and 12 with postlaminar invasion. All but one were postoperatively classified as stage I by the International Retinoblastoma Staging System. The accuracy of CE-T1 sequences in identifying ON invasion was limited (AUC = 0.64; 95 % CI, 0.55 - 0.72) and not confirmed for postlaminar invasion diagnosis (AUC = 0.64; 95 % CI, 0.47 - 0.82); high specificities (range, 0.64 - 1) and negative predictive values (range, 0.81 - 0.97) were confirmed.

CONCLUSION

HR-MRI with surface coils is recommended to appropriately select retinoblastoma patients eligible for primary enucleation without the risk of IRSS stage II but cannot substitute for pathology in differentiating the first degrees of ON invasion.

KEY POINTS

• HR-MRI excludes advanced optic nerve invasion with high negative predictive value. • HR-MRI accurately selects patients eligible for primary enucleation. • Diagnosis of early stages of optic nerve invasion still relies on pathology. • Several physiological MR patterns may mimic optic nerve invasion.

Successful treatment of macular retinoblastoma with superselective ophthalmic artery infusion of melphalan

PURPOSE

To report our experience with superselective ophthalmic artery infusion of melphalan (SOAIM) for macular retinoblastoma to obtain tumor control while preserving as much useful vision as possible.

METHODS

Five patients with newly diagnosed unilateral retinoblastoma involving the macula were selected within a group of patients eligible for SOAIM as the primary treatment.

RESULTS

The mean tumor basal dimension and thickness in this group of five patients with macular retinoblastoma were 11.6 and 12.3 mm, respectively. The stage at diagnosis ranged from II to VB (Reese-Ellsworth) or B to D (International Classification System). Tumor regression with SOAIM was achieved in all cases with regression patterns type I in four cases and III in one case.

CONCLUSIONS

SOAIM can be of value in the treatment of macular retinoblastoma. It may allow the salvage of the residual eyesight with a low rate of complications due to the local and systemic toxicity related to chemotherapy.

Superselective ophthalmic artery infusion of melphalan for intraocular retinoblastoma: preliminary results from 140 treatments

PURPOSE

To report our experience in superselective ophthalmic artery infusion of melphalan (SOAIM) for intraocular retinoblastoma.

METHODS

  From June 2008 to October 2010, 38 patients (18 women, 20 men; age range at first treatment, 7 months to 22 years) with 41 eyes with retinoblastoma were scheduled for SOAIM, for 17 newly diagnosed retinoblastomas Tumour, Node and Metastasis (TNM) 7th Edition 1a (n = 1), 1b (n = 1), 2a (n = 7), 2b (n = 4) and 3a (n = 4) and 24 retinoblastomas with partial remission/relapse TNM 7th Edition 1b (n = 13), 2a (n = 1) and 2b (n = 10). Eight patients (ten eyes) have been treated by SOAIM alone. Follow-up was 6-27 months in 28 patients (30 eyes).

RESULTS

Ophthalmic artery cannulation failed in two patients. Thirty-six patients underwent 140 treatments by internal (n = 112) or external (n = 28) carotid arteries. No major procedural complications occurred. Two patients have been lost to follow-up. Remaining 34 patients (37 eyes) had no metastatic disease. Four patients suffered permanent ocular complications: chorioretinal dystrophy (n = 2), ptosis (n = 1) and strabismus/exotropia (n = 1). Eight (22%) eyes in eight (24%) patients underwent enucleation: 7/16 (43%) newly diagnosed retinoblastomas and 1/22 (4.5%) retinoblastomas undergoing partial remission/relapse. For all treated eyes, Kaplan-Meier eye enucleation-free rates (K-M) were 85.4% (95% CI, 73.3-97.5%), 74.4% (95% CI, 57-91.8%) and still stable at 6, 12 months and 2 years, respectively. For eyes with partial remission/relapse, and eyes at presentation, K-M at 2 years were 95.5% (95% CI, 86.9-100%) and 45.6% (95% CI, 16.6-74.6%), respectively.

CONCLUSION

Superselective ophthalmic artery infusion of melphalan was safe and powerful, especially following other therapies. Superselective ophthalmic artery infusion of melphalan should be added to focal therapies spectrum. In selected cases, melphalan should be combined with other chemotherapeutic agents.

Bilateral retinoblastoma: clinical presentation, management and treatment

Management of retinoblastoma (Rb), the most common intraocular malignant tumor in childhood, is tailored to each individual case and based on the overall situation. We present a case of bilateral Rbs in a 4-month-old girl, referred to our center for bilateral leukocoria. In the right eye, the optic disc was partially visible, and three large foci of retinoblastoma were noted adjective in the vitreous cavity with satellite retinal detachment. The macula was obscured by the tumors. The tumor was therefore classified as group D (International classification of retinoblastoma), and thus underwent intravenous chemotherapy with the standard three-agent protocol of ifosfamide, carboplatin and etoposide (ICE protocol) delivered monthly for six cycles, regressing with a type I calcified pattern. The left eye presented three multifocal yellow-white retinal masses, with a total retinal detachment, and secondary glaucoma. The lesions were classified as group E and, therefore, taking the results obtained by Shields et al. in group E tumors into consideration, underwent enucleation. This case clearly shows that this cancer is curable if detected at a stage in which it is still contained within the retina, subretinal space or vitreous, and that the management of Rb relies on an experienced team of ocular oncologists, pediatricians and pediatric ophthalmologists working together for the single goal of saving the child's life.

Epigenetic and copy number variation analysis in retinoblastoma by MS-MLPA

Retinoblastoma is the most common primary intraocular malignancy in children. Two step inactivation of RB1 (M1-M2) represents the key event in the pathogenesis of retinoblastoma but additional genetic and epigenetic events (M3-Mn) are required for tumor development. In the present study, we employed Methylation Specific Multiplex Ligation Probe Assay to investigate methylation status and copy number changes of 25 and 39 oncosuppressor genes, respectively. This technique was applied to analyse 12 retinoblastomas (5 bilateral and 7 unilateral) and results were compared to corresponding normal retina. We identified hypermethylation in seven new genes: MSH6 (50%), CD44 (42%), PAX5 (42%), GATA5 (25%), TP53 (8%), VHL (8%) and GSTP1 (8%) and we confirmed the previously reported hypermethylation of MGMT (58%), RB1 (17%) and CDKN2 (8%). These genes belong to key pathways including DNA repair, pRB and p53 signalling, transcriptional regulation, protein degradation, cell-cell interaction, cellular adhesion and migration. In the same group of retinoblastomas, a total of 29 copy number changes (19 duplications and 10 deletions) have been identified. Interestingly, we found deletions of the following oncosuppressor genes that might contribute to drive retinoblastoma tumorigenesis: TP53, CDH13, GATA5, CHFR, TP73 and IGSF4. The present data highlight the importance of epigenetic changes in retinoblastoma and indicate seven hypermethylated oncosuppressors never associated before to retinoblastoma pathogenesis. This study also confirms the presence of copy number variations in retinoblastoma, expecially in unilateral cases (mean 3 ± 1.3) where these changes were found more frequently respect to bilateral cases (mean 1.4 ± 1.1).

Analysis of aqueous humour proteins in patients with retinoblastoma

BACKGROUND

To investigate aqueous humour protein composition from retinoblastoma patients.

DESIGN

Prospective, hospital-based study.

PARTICIPANTS

Eighteen retinoblastoma patients (Reese-Ellsworth stage V or ABC classification group E RB) undergoing ocular enucleation, and 10 normal subjects undergoing cataract surgery. Five of 18 patients presented with associated secondary glaucoma whereas 13 had no secondary glaucoma; 5 of 13 patients with no secondary glaucoma received chemotherapeutical treatment with melphalan.

METHODS

Aqueous humour samples were collected by limbal paracentesis of the anterior chamber after ocular enucleation in patients and after the stab peripheral corneal incision in controls. Total protein concentration according to Bradford method and sodium dodecyl sulphate-polyacrylamide gel electrophoresis of the samples were performed.

MAIN OUTCOME MEASURE

Aqueous humour protein concentration.

RESULTS

Aqueous humour protein concentration was significantly higher in retinoblastoma patients than controls (P < 0.01); patients with secondary glaucoma presented the highest values (P < 0.05 vs. controls); patients treated with melphalan presented a significant decrease (P < 0.01) versus non-treated; controls did not significantly differ from treated patients. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis pattern in retinoblastoma patients who did not receive any treatment was very different either from treated or from controls.

CONCLUSION

This study represents a preliminary step towards a more accurate two dimensional electrophoresis (2DE) pattern, which will be combined with mass spectrometry analysis to clarify the potential role of specific proteins in tumour development and progression; although these results suggest that aqueous humour protein pattern in retinoblastoma is characteristic, several aspects of the study are still under investigation.

Downregulation and aberrant promoter methylation of p16INK4A: a possible novel heritable susceptibility marker to retinoblastoma

RB loss has long been recognized as the causative genetic alteration underlying retinoblastoma but it is increasingly evident that other alterations are required for the tumor to develop. Therefore, we set out to identify additional inheritable susceptibility markers and new potential preventive and therapeutic targets for retinoblastoma. We focused on the p16INK4A tumor suppressor gene because of its possible role in retinoblastoma pathogenesis and its involvement in predisposition to familial cancer. p16INK4A expression was analyzed in tumor samples from retinoblastoma patients by immunohistochemistry and in peripheral blood cells from both patients and their parents by real-time quantitative reverse transcription-PCR (qRT-PCR). Since promoter methylation is a common mechanism regulating p16INK4A expression, the methylation status of its promoter was also analyzed in blood samples from patients and their parents by methylation-specific PCR. A downregulation of p16INK4A was observed in 55% of retinoblastoma patients. Interestingly, in 56% of the cases showing p16INK4A downregulation at least one of the patients' parents bore the same alteration in blood cells. Analysis of p16INK4A promoter methylation showed hypermethylation in most patients with p16INK4A downregulation and in the parents with the same alteration in p16INK4A expression. The finding that p16INK4A was downregulated both in patients and their parents suggests that this alteration could be a novel inheritable susceptibility marker to retinoblastoma. The observation that p16INK4A downregulation seems to be due to its promoter hypermethylation opens the way for the development of new preventive and therapeutic strategies using demethylating agents.

Growth of congenital malignant teratoid medulloepithelioma of the ciliary body: a case study

The purpose of this study was to describe the growth pattern of congenital malignant teratoid medulloepithelioma of the ciliary body by reporting clinical and imaging findings with pathological correlation. An 11-month-old little girl presented with a whitish-pink iris mass in the right eye resulting from a small ciliary body mass consistent with medulloepithelioma at both clinical and computed tomography (CT) findings. At CT, the lesion showed heterogeneous attenuation, without intraocular calcifications. Eleven months later, clinical and ultrabiomicroscopy showed a clear enlargement of the mass, which invaded the pupil. At magnetic resonance imaging (MRI), the lesion showed T1-weighted hyperintensity and T2-weighted slight hypointensity when compared to the vitreous and a notch in the anterolateral aspect of the ipsilateral lens. After intravenous gadolinium administration, the lesion showed intense homogeneous enhancement, and there was leakage of gadolinium in the anterior chamber, resulting from impairment of blood-aqueous barrier. Biopsy revealed a malignant teratoid medulloepithelioma. The eye was then enucleated, and histology confirmed the diagnosis. Systemic chemotherapy and radiotherapy were not performed, since there was no extraocular extension. The 57-month clinical and MRI follow-up did not show disease relapse. This uncommon case displays the natural history of congenital malignant teratoid medulloepithelioma of the ciliary body. While the tumour might have been successfully treated by local excision at diagnosis, the delay in surgical treatment led to tumour overgrowth with consequent need for enucleation. The most important prognostic feature is extraocular extension, which carries a risk of local recurrence, eventually resulting in intracranial extension and/or lymphatic spread.

Is CT still useful in the study protocol of retinoblastoma?

BACKGROUND AND PURPOSE

Intralesional calcium deposition is considered a key element for differentiating retinoblastoma from simulating lesions. Our aim was to assess whether MR imaging associated with ophthalmologic investigations (ophthalmoscopy and ultrasonography) could replace CT in the detection of diagnostic intralesional calcifications in retinoblastoma.

MATERIALS AND METHODS

Ophthalmoscopic findings, MR images, CT scans, and histologic examination of 28 retinoblastomas from 23 consecutive children (11 males, 12 females; age range at admission, 1-35 months; mean age, 11 months; median age, 9 months) were retrospectively evaluated. Ultrasonography was performed in 18 patients with 21 retinoblastomas. MR imaging included T2-weighted spin-echo and gradient-echo images, fluid-attenuated inversion recovery images, and T1-weighted spin-echo images with and without contrast enhancement. Clinical data were integrated with MR imaging data to evaluate the utility of both approaches to discover calcifications; particularly, a correlation between intralesional signal-intensity void spots on MR imaging and hyperattenuating areas on CT scans was performed.

RESULTS

Ophthalmoscopy detected calcifications in 12 of 28 eyes (42.85%). Ultrasonography detected calcifications in 20 of 21 eyes (95.23%). CT showed hyperattenuating intralesional areas consistent with calcifications in 27 of 28 eyes (96.42%). MR imaging showed intralesional signal-intensity void spots in 25 of 28 eyes (89.28%). All spots detected with MR imaging matched the presence of calcifications on CT scans. Gradient-echo T2*-weighted and fast spin-echo T2-weighted images showed the highest degree of correlation with CT. When we put together ophthalmoscopy, ultrasonography, and MR imaging data, no calcifications detected on CT were missed, and the differential diagnosis was thorough.

CONCLUSIONS

A combination of clinical data and MR images may remove potentially harmful ionizing radiation from the study protocol of retinoblastoma.

Genomic differences between retinoma and retinoblastoma

INTRODUCTION

Genomic copy number changes are involved in the multi-step process transforming normal retina in retinoblastoma after RB1 mutational events. Previous studies on retinoblastoma samples led to a multi-step model in which after two successive RB1 mutations, further genomic changes accompany malignancy: 1q32.1 gain is followed by 6p22 gain, that in turn is followed by 16q22 loss and 2p24.1 gain. Retinoma is a benign variant of retinoblastoma that was initially considered a tumor regression, but recent evidences suggest that it rather represents a pre-malignant lesion. Genetic studies on retinoma tissue have rarely been performed.

MATERIALS AND METHODS

We investigated by Real-Time qPCR, copy number changes of candidate genes located within the 4 hot-spot regions (MDM4 at 1q32.1, MYCN at 2p24.1, E2F3 at 6p22 and CDH11 at 16q22) in retina, retinoma and retinoblastoma tissues from two different patients.

RESULTS

Our results demonstrated that some copy number changes thought to belong to early (MDM4 gain) or late stage (MYCN and E2F3 gain) of retinoblastoma are already present in retinoma at the same (for MDM4) or at lower (for MYCN and E2F3) copy number variation respect to retinoblastoma. CDH11 copy number is not altered in the two retinoma samples, but gain is present in one of the two retinoblastomas.

DISCUSSION

Our results suggest that MDM4 gain may be involved in the early transition from normal retina to retinoma, while MYCN and E2F3 progressive gain may represent driving factors of tumor progression. These results also confirm the pre-malignant nature of retinoma.