Intraocular medulloepithelioma clinical features and management of 11 cases

AIMS

To describe the clinical features, imaging characteristics, histopathology, treatment and outcomes of intraocular medulloepithelioma.

METHODS

Medical records of 11 patients with clinically or histopathologically confirmed medulloepithelioma were retrieved and reviewed. Clinical features, diagnostic challenges, imaging characteristics, management, histopathology and prognosis were assessed.

RESULTS

The median age of the patients at initial diagnosis was 4 years, with the most common manifestations being leukocoria (five eyes), loss of vision (four eyes), ocular pain (one eye) and ophthalmic screening (one eye). The clinical signs include a grey-white ciliary body lesion, cataract or lens subluxation, secondary glaucoma and evident cysts. The ultrasound biomicroscopy (UBM) imaging most commonly displays ciliary body mass with intratumoural cysts (nine eyes). Three patients underwent surgery for cataract or glaucoma while the tumours were incidentally found. Two of the three patients managed by eye preserve treatments eventually required enucleation because of local tumour recurrence or phthisis. One patient treated with intra-arterial chemotherapy and cryotherapy had successful tumour regression and globe salvage.

CONCLUSIONS

Initial misdiagnosis, delay in diagnosis and subsequent misdirected management is not uncommon in medulloepithelioma. The presence of multiple cysts in the tumour and retrolental neoplastic cyclitic membrane detected by UBM can offer certain information. Selective intra-arterial melphalan may prevent further tumour growth, but longer follow-up is necessary until treatment efficacy is fully evaluated.

A Review of Pediatric Ophthalmic Tumors

Tumors of the eye, orbit, and ocular adnexa can arise in the pediatric population. These entities can be both vision- and life-threatening and may be associated with systemic disease. Given their relative rarity, pediatricians must be aware of these conditions and understand what findings warrant immediate referral to an ophthalmologist for initiation of further testing. We aimed to review these conditions and highlight clinical features to promote awareness and expedite diagnosis. Tumors are subdivided into the following categories for review: anterior tumors of the eyelid and ocular surface, orbital tumors, and intraocular tumors.

An advanced case of pediatric ciliary body medulloepithelioma with detailed literature review

INTRODUCTION AND IMPORTANCE

Medulloepithelioma is the second most common primary intraocular malignant tumor in children but is often diagnosed late, which worsens the prognosis.

CASE PRESENTATION

We are reporting a 6-year-old boy presenting with a ciliary body (CB) teratoid malignant medulloepithelioma (TMM), which was missed at the initial presentation. We added our case to the 97 previously reported cases in our literature review that were confirmed by cytological or histopathological examination.

DISCUSSION

Medulloepithelioma has a wide age range at presentation with a mean of 5.3 ± 4.1 years, and slight male predominance (M: F ratio of 1.15). Clinically, the main symptoms/ signs are reduced visual acuity, lens changes, or a pupil "mass." Almost all reported medulloepitheliomas were unilateral (98 %). Histopathologically, non-teratoid malignant medulloepithelioma (NTMM) (35.7 %) and TMM (34.5 %) were the commonest. Enucleation was the main treatment modality because of the large tumor size of 72.7 %. A combination of chemotherapy and/or radiotherapy was used in 15.1 % and brachytherapy for small lesions in 14.1 %. Orbital exenteration was needed in 3 cases because of orbital invasion.

CONCLUSION

A CB medulloepithelioma tumor can be easily missed, diagnosed late, with less chance for globe salvaging. The malignant types are more common and may result in orbital invasion, requiring even more extensive surgery. Therefore, when facing a child with lens changes, a pupil "mass," or raised intraocular pressure, pediatricians and general ophthalmologists must have an earlier suspicion and be aware of this rare entity to improve outcomes and reduce loss of vision or other disease-related morbidity.

The role of EZH2 in ocular diseases: a narrative review

EZH2, acting as a catalytic subunit of PRC2 to catalyze lysine 27 in histone H3, induces the suppression of gene expression. EZH2 can regulate cell proliferation and differentiation of retinal progenitors, which are required for physiological retinal development. Meanwhile, an abnormal level of EZH2 has been observed in ocular tumors and other pathological tissues. This review summarizes the current knowledge on EZH2 in retinal development and ocular diseases, including inherited retinal diseases, ocular tumors, corneal injury, cataract, glaucoma, diabetic retinopathy and age-related retinal degeneration. We highlight the potential of targeting EZH2 as a precision therapeutic target in ocular diseases.

Malignant teratoid intraocular ciliary body medulloepithelioma in a 5-year-old male with corresponding somatic copy number alteration profile of aqueous humor cell-free DNA

BACKGROUND

Intraocular, ciliary body, medulloepithelioma (CBME) is a rare tumor of the nonpigmented ciliary body epithelium, typically presenting in childhood. We describe a case of CBME.

MATERIALS AND METHODS

Ocular examination and imaging guided diagnostic and treatment decisions. Aqueous humor (AH) liquid biopsy was collected from the affected eye at eventual enucleation. Whole genome sequencing (WGS) was employed to determine somatic copy number alterations (SCNA) in AH cell-free DNA (cfDNA). Tumor sample was analyzed using various assays to evaluate for oncogenic mutations and SCNAs. Histopathology determined diagnosis.

RESULTS

A 5-year-old male with glaucoma and cataract in the left eye (OS) experienced worsening left eye pain and redness. There was no light perception OS and the eye was hypotonus. Anterior segment exam showed complete cataract and rubeosis iridis. Ocular B-scan ultrasound OS revealed an intraocular lesion with calcifications and retinal detachment. Orbital MRI suggested left globe hypercellularity. An infiltrative lesion involving the ciliary body was seen in the left eye on examination under anesthesia. Left eye enucleation was performed in the setting of pain, blindness, and tumor, with anterior chamber paracentesis for AH liquid biopsy collection. SCNA profile of AH cfDNA demonstrated loss of copy of chromosomes 4, 6, and 9. Tumor was negative for clinically significant mutations or SCNAs. Histopathology diagnosed malignant teratoid CBME.

CONCLUSIONS

We present a case of CBME and include the unique SCNA profile of AH cfDNA from the enucleated eye. This case suggests utility of AH liquid biopsy in distinguishing between differential diagnoses for intraocular mass lesions.

Extracranial medulloepithelioma: a review of the literature

PURPOSE

Medulloepithelioma is a rare, malignant tumor that typically arises in the periventricular region of the cerebral hemispheres or the ciliary body of the eye. Even rarer still is the extracranial manifestation of medulloepithelioma with only 12 cases reported to date. Our purpose is to report a case of an intradural, extra-medullary medulloepithelioma and review the limited literature about diagnosis and treatment of this extremely rare pathology.

METHODS

PubMed was queried using search terms "peripheral medulloepithelioma" and "pre-sacral medulloepithelioma." Medulloepitheliomas which were intraocular or occurred in reproductive organs were excluded. Patients' age, sex, the symptomatic period prior to diagnosis, primary tumor site, stage, treatment regimen, pathologic description, and survival outcomes were collected.

RESULTS

We present a case of extracranial medulloepithelioma in an 8-year-old male. Morphology of the neoplasm was representative of medulloepithelioma but there was no amplification of C19MC. Additionally, the neoplasm stained positive for CD99. Twelve other cases of extracranial medulloepithelioma were found in literature review.

CONCLUSIONS

The rarity of extracranial medulloepithelioma makes for a challenging diagnosis. Designing an optimal treatment strategy is difficult because of a scarcity of cases and wide variety in locations and treatments. Our case provides an example of treatment including resection, intense induction chemotherapy, consolidation with high-dose chemotherapy and stem cell rescue, craniospinal proton radiation therapy, and metronomic chemotherapy.

Systemic adjuvant chemotherapy for advanced malignant ocular medulloepithelioma

BACKGROUND

Ocular medulloepithelioma (diktyoma) is a rare and potentially malignant paediatric tumour of the non-pigmented ciliary epithelium. Adjuvant chemotherapy can be given in advanced cases, but the indications and regimens remain to be defined. The aim was to identify whether adjuvant chemotherapy offers treatment benefit in advanced ocular medulloepithelioma.

METHODS

This was a retrospective case series of subjects referred to a single specialist ocular oncology centre for advanced ocular medulloepithelioma subsequently treated with enucleation, including those needing adjuvant systemic vincristine, etoposide and carboplatin. A case-note review was performed for included subjects meeting referral criteria. The outcomes were histopathology characteristics, recurrence, metastases and survival.

RESULTS

Between March 2010 and June 2017, four male patients (mean age 31 months) underwent enucleation for ocular medulloepithelioma. Adjuvant chemotherapy was commenced in 3 patients (75%) due to malignant histopathological features. With a mean follow-up time of 81.5 months (median 71 months, range 49-135 months) none of the patients have had recurrence, metastases or death from the tumour.

CONCLUSIONS

This series is unique in reporting the management of advanced malignant ocular medulloepithelioma with adjuvant systemic vincristine, etoposide and carboplatin for advanced tumours with malignant features. This regimen appears to be safe and may be effective in preventing metastatic spread.

Co-activation of Sonic hedgehog and Wnt signaling in murine retinal precursor cells drives ocular lesions with features of intraocular medulloepithelioma

Intraocular medulloepithelioma (IO-MEPL) is a rare embryonal ocular neoplasm, prevalently occurring in children. IO-MEPLs share histomorphological features with CNS embryonal tumors with multilayered rosettes (ETMRs), referred to as intracranial medulloepitheliomas. While Sonic hedgehog (SHH) and WNT signaling pathways are crucial for ETMR pathogenesis, the impact of these pathways on human IO-MEPL development is unclear. Gene expression analyses of human embryonal tumor samples revealed similar gene expression patterns and significant overrepresentation of SHH and WNT target genes in both IO-MEPL and ETMR. In order to unravel the function of Shh and Wnt signaling for IO-MEPL pathogenesis in vivo, both pathways were activated in retinal precursor cells in a time point specific manner. Shh and Wnt co-activation in early Sox2- or Rax-expressing precursor cells resulted in infiltrative ocular lesions that displayed extraretinal expansion. Histomorphological, immunohistochemical, and molecular features showed a strong concordance with human IO-MEPL. We demonstrate a relevant role of WNT and SHH signaling in IO-MEPL and report the first mouse model to generate tumor-like lesions with features of IO-MEPL. The presented data may be fundamental for comprehending IO-MEPL initiation and developing targeted therapeutic approaches.

Medulloepithelioma in newborn: Advanced clinical status

We report three cases of congenital medulloepithelioma, which is an extremely rare clinical pattern of a tumor rare by definition. The aim of this study is to underline the clinical features of advanced medulloepithelioma in newborns.

Subconjunctival Mass as Rare Presentation of Even Rarer Intraocular Medulloepithelioma: A Case Report

Medulloepithelioma is a rare childhood embryonal tumor arising from the non-pigmented ciliary epithelium of the pars plicata. We report a case of an 11-year-old male who presented with painless loss of vision of the right eye for the last three years and progressively increasing mass on the superior aspect of the globe for the last three months. On ocular examination, a firm, non-tender mass of 4cm × 3cm was noted in the superior aspect of the globe. CT-Scan of the orbit was suggestive of a foreign body with a haemorrhage or infection. The patient underwent enucleation with minimal manipulation. Histopathological examination of the enucleated globe revealed medulloepithelioma.

The intraocular medulloepithelioma presentation is often late and masquerading, which may lead to extraocular extension and metastasis and ultimately unfavorable prognosis.

Successful treatment of ciliary body medulloepithelioma with intraocular melphalan chemotherapy: a case report

Background

Intraocular medulloepithelioma is commonly treated with primary enucleation. Conservative treatment options include brachytherapy, local resection and/or cryotherapy in selected cases. We report for the first time the use of targeted chemotherapy to treat a ciliary body medulloepithelioma with aqueous and vitreous seeding.

Case presentation

A 17-month-old boy with a diagnosis of ciliary body medulloepithelioma with concomitant seeding and neovascular glaucoma in the right eye was seen for a second opinion after parental refusal of enucleation. Examination under anesthesia showed multiple free-floating cysts in the pupillary area associated with iris neovascularization and a subluxated and notched lens. Ultrasound biomicroscopy revealed a partially cystic mass adjacent to the ciliary body between the 5 and 9 o’clock meridians as well as multiple nodules in the posterior chamber invading the anterior vitreous inferiorly. Fluorescein angiography demonstrated peripheral retinal ischemia. Left eye was unremarkable. Diagnosis of intraocular medulloepithelioma with no extraocular invasion was confirmed and conservative treatment initiated with combined intracameral and intravitreal melphalan injections given according to the previously described safety-enhanced technique. Ciliary tumor and seeding totally regressed after a total of 3 combined intracameral (total dose 8.1 μg) and intravitreal (total dose 70 μg) melphalan injections given every 7–10 days. Ischemic retina was treated with cryoablation as necessary. Three years later, ab interno trabeculotomy followed by 360° gonioscopy-assisted transluminal trabeculotomy 6 months later was performed for uncontrolled intraocular pressure despite antihypertensive drugs combined to cyclophotocoagulation and 7 intravitreal anti-VEGF injections for recurrent iris neovascularization. Cataract was removed at the same operative time. The child has remained disease- and metastasis-free at a 5-year follow-up since the last melphalan injection (25-month follow-up after the combined lensectomy-trabeculotomy) with a controlled intraocular pressure under topical quadritherapy and a best corrected Snellen visual acuity of 0.08.

Conclusions

We report for the first time complete regression of a non-infiltrating ciliary body medulloepithelioma with seeding achieved with only a small number of intracameral and intravitreal melphalan injections. Concomitant secondary neovascular glaucoma and cataract needed appropriate management to allow long-term eye and vision preservation.

An update on the central nervous system manifestations of DICER1 syndrome

DICER1 syndrome is a rare tumor predisposition syndrome with manifestations that predominantly affect children and young adults. The syndrome is typically caused by heterozygous germline loss-of-function DICER1 alterations accompanied on the other allele by somatic missense mutations occurring at one of a few mutation hotspots within the sequence encoding the RNase IIIb domain. DICER1 encodes a member of the microRNA biogenesis machinery. The syndrome spectrum is highly pleiotropic and features a unique constellation of benign and malignant neoplastic and dysplastic lesions. Pleuropulmonary blastoma (PPB), the most common primary lung cancer in children, is the hallmark tumor of the syndrome. Other manifestations include ovarian Sertoli-Leydig cell tumor, cystic nephroma arising in childhood, multinodular goiter, thyroid carcinoma, anaplastic sarcoma of the kidney, embryonal rhabdomyosarcoma, and nasal chondromesenchymal hamartoma, in addition to other rare entities. Several central nervous system (CNS) manifestations have also been defined, including metastases of PPB to the cerebrum, pituitary blastoma, pineoblastoma, ciliary body medulloepithelioma, and most recently primary DICER1-associated CNS sarcomas and ETMR-like infantile cerebellar embryonal tumor. Macrocephaly is a recently reported non-neoplastic, haploinsufficient phenotype. In this manuscript, we review the CNS manifestations of DICER1 syndrome.

Intraocular medulloepithelioma - A review of clinical features, DICER 1 mutation, and management

Intraocular medulloepithelioma is a nonhereditary neoplasm of childhood arising from primitive medullary epithelium. It most often involves the ciliary body. Most patients present between 2 and 10 years of age with loss of vision, pain, leucocoria, or conjunctival congestion. The mass appears as a grey-white ciliary body lesion with intratumoral cysts. Presence of a neoplastic cyclitic membrane with extension to retrolental region is characteristic. Secondary manifestations like cataract and neovascular glaucoma may be present in up to 50% and 60% patients, respectively. These could be the first signs for which, unfortunately, about 50% patients undergo surgery before recognition of the hidden tumor. Systemic correlation with pleuropulmonary blastoma (DICER1 gene) has been documented in 5% cases. Histopathology shows primitive neuroepithelial cells arranged as cords closely resembling the primitive retina. Histopathologically, the tumor is classified as teratoid (containing heteroplastic elements) and nonteratoid (containing medullary epithelial elements), each of which are further subclassified as benign or malignant. Retinoblastoma-like and sarcoma-like areas may be seen within the tissue. The treatment modality depends on tumor size and extent of invasion. For small localized tumors (≤3-4 clock hours), conservative treatments with cryotherapy, plaque radiotherapy, or partial lamellar sclerouvectomy (PLSU) have been used. Plaque brachytherapy is generally preferred for best tumor control. Advanced and extensive tumors require enucleation. Rare use of intra-arterial and intravitreal chemotherapy has been employed. Systemic prognosis is favorable, but those with extraocular extension and orbital involvement show risk for local recurrence and metastatic disease, which can lead to death.

Ocular non-teratoid medulloepithelioma with teratoid metastases in ipsilateral intraparotid lymph nodes

PURPOSE

To describe a rare presentation of a case of intraocular non-teratoid medulloepithelioma with teratoid metastases in ipsilateral intraparotid lymph nodes.

CASE DESCRIPTION

A 9-year-old male child with previous history of ciliary body non-teratoid medulloepithelioma presented with a swelling in the right pre-auricular region for 1 month. Magnetic resonance imaging and positron emission tomography-computed tomography showed a right intraparotid mass with enlarged ipsilateral cervical lymph nodes. A core biopsy was taken from the lesion, which on microscopy showed a tumor composed of small round cells arranged in cords, tubules lined by multilayered cells, and in cribriform pattern. These cells were embedded in a hypocellular, loose myxoid matrix. Based on the histopathological characteristics and previous history, a diagnosis of medulloepithelioma metastastic to ipsilateral parotid gland was made. The patient underwent right total conservative parotidectomy and bilateral neck dissection. Histopathological examination revealed metastatic medulloepithelioma in five out of eight intraparotid lymph nodes, with extranodal extension into the adjacent parotid parenchyma. Foci of hyaline cartilage were identified within the tumor, leading to a diagnosis of metastatic teratoid medulloepithelioma.

CONCLUSION

Intraparotid lymph node metastases from intraocular medulloepithelioma is a rare possibility and we recommend that the parotid should be evaluated in cases of intraocular medulloepithelioma at initial presentation as well as during the follow-up period. Also, metastasis should be considered in all pediatric patients with solitary mass lesions showing unconventional histology for a primary parotid neoplasm.

Intraocular Medulloepithelioma: AIRP Best Cases in Radiologic-Pathologic Correlation

Editor's Note.-RadioGraphics continues to publish radiologic-pathologic case material selected from the American Institute for Radiologic Pathology (AIRP) "best case" presentations. The AIRP conducts a 4-week Radiologic Pathology Correlation Course, which is offered five times per year. On the penultimate day of the course, the best case presentation is held at the American Film Institute Silver Theater and Cultural Center in Silver Spring, Md. The AIRP faculty identifies the best cases, from each organ system, brought by the resident attendees. One or more of the best cases from each of the five courses are then solicited for publication in RadioGraphics. These cases emphasize the importance of radiologic-pathologic correlation in the imaging evaluation and diagnosis of diseases encountered at the institute and its predecessor, the Armed Forces Institute of Pathology (AFIP).

Pediatric Intraocular Immature Teratoma Associated With Sacrococcygeal Teratoma

Intraocular teratomas are rare neoplasms with only three previously reported cases. We present the fourth case of intraocular teratoma and the second associated with sacrococcygeal teratoma. While the nature of the association between intraocular teratomas and sacrococcygeal teratomas is unclear, it suggests a need for careful ophthalmologic follow-up of infants with congenital sacrococcygeal teratomas.

Malignant Ciliary Body Medulloepithelioma With Brain and Parotid Metastasis

A 12-year-old girl with malignant ciliary medulloepithelioma and parotid metastasis was treated with semi-exenteration of the orbit and external beam radiotherapy. She had brain metastasis 7 months later and was treated with salvage chemotherapy. The patient was disease free at 11 months of follow-up. In aggressive cases, exenteration combined with radiotherapy and chemotherapy are necessary for disease control. [J Pediatr Ophthalmol Strabismus. 2017;54:e18-e22].

[Malignant medulloepithelioma mimicking retinoblastoma - clinical and morphological case analysis and cell culture experience]

The paper presents clinical and morphological case analysis of primary intraocular malignant medulloepitelioma (medulloblastoma) of rare localization (central part of the retina with optic nerve involvement) that simulated retinoblastoma in a 2-year-old child. Histological features of the tumor are given in details (tubular and mesh structures of the tumor, rosettes, ribbons, cells with hyperchromic nuclei, and cellular polymorphism). An experience of creating a primary intraocular malignant medulloepitelioma cell culture, as yet exclusive in the Russian Federation, is described. Culture sensitivity for particular drugs (oxaliplatin, irinotecan, ifosfamide, and ascorbic acid at different concentrations) was evaluated by MTT-assay. Of the four products, IC50 (3.3 mg/ml) was obtained only for ascorbic acid. Despite the relative rarity of primary intraocular malignant medulloepitelioma, its differential diagnosis should be carried out, with retinoblastoma in mind in the first place. The obtained data on the effectiveness of ascorbic acid against intraocular malignant medulloepitelioma cells can be used to supplement the existing chemotherapeutic protocols in pediatric ocular and neuro-oncology.

Somatic mutations of DICER1 and KMT2D are frequent in intraocular medulloepitheliomas

Intraocular medulloepithelioma (IO-MEPL) is an uncommon embryonal neuroepithelial neoplasm of the eye. Little is known about the cytogenetics, molecular biology, and pathogenesis of this tumor. In the present study we investigated the mutational landscape of 19 IO-MEPL using targeted next-generation sequencing. Routinely prepared paraffin-embedded samples were assessed with high-coverage genome sequencing on the Illumina NextSeq 500 platform using a customized gene panel set covering the coding region of 130 genes. This revealed several notable genomic alterations, including mutations of DICER1 (6 tumors) and KMT2D (also known as MLL2; 5 tumors)-which are frequently recurrent and mutually exclusive molecular events for IO-MEPL. Non-recurrent mutations in the cancer-associated genes BRCA2, BRCA1, NOTCH2, CDH1, and GSE1 were also identified. IO-MEPL samples harboring a DICER1 mutation disclosed few chromosomal alterations and formed a separate DNA methylation cluster, indicating potential differences in genetic and epigenetic events arising perhaps from the presence of this aberration in the tumor genome. The high proportion of recurrent somatic DICER1 and KMT2D mutations in this series of sporadic IO-MEPL points to their likely important roles in the molecular pathogenesis of these rare embryonal tumors, and perhaps suggests the existence of distinct molecular variants of IO-MEPL. Although the precise role of these recurrent mutations in the development of IO-MEPL, and their relationship to pro-oncogenic molecular mechanisms, have yet to be determined, unraveling their roles could eventually be exploited for nonsurgical therapies of these neoplasms.

Comparative integrated molecular analysis of intraocular medulloepitheliomas and central nervous system embryonal tumors with multilayered rosettes confirms that they are distinct nosologic entities

Intraocular medulloepithelioma (IO MEPL) is an uncommon embryonal neuroepithelial neoplasm of the eye. These ocular neoplasms have been compared with intracranial medulloepitheliomas or other histologic variants of CNS embryonal tumor with multilayered rosettes (CNS ETMR) due to their morphological mimicry. We performed comprehensive molecular analysis to explore the histogenetic and biologic relationships between 22 IO MEPL and 68 CNS ETMR. Routinely prepared paraffin-embedded samples were assessed for genome-wide methylation profiles using the Illumina Methylation 450k BeadChip array. We identified strong cytogenetic and epigenetic differences between ocular neoplasms and CNS ETMR. None of the IO MEPL cases displayed the ETMR-specific amplification of the C19MC locus. Instead, cytogenetic analysis of the IO MEPL showed numerous copy number aberrations which involved either whole chromosomes or chromosomal arms; recurrent aberrations in these tumors affected chromosomes 1p, 4, 8 and 16p. DNA methylation patterns were also strikingly different between these two tumor entities, suggesting that they do not share common origins and biological behaviors. Comparative cluster analysis of 198 pediatric CNS tumors and 22 IO MEPL revealed a clear demarcation of the CNS ETMR and IO MEPL profiles from other CNS entities. In conclusion, although IO MEPL shares some histopathological features with CNS ETMR, they manifest striking molecular diversity at the cytogenetic and epigenetic levels. Consequently they deserve a separate nosologic designation in future tumor classifications, where CNS MEPL could be designated as a histological variant of CNS ETMR.

MicroRNA profiling in intraocular medulloepitheliomas

Purpose

To study the differential expression of microRNA (miRNA) profiles between intraocular medulloepithelioma (ME) and normal control tissue (CT).

Material and Methods

Total RNA was extracted from formalin fixed paraffin embedded (FFPE) intraocular ME (n=7) and from age matched ciliary body controls (n=8). The clinical history and phenotype was recorded. MiRNA profiles were determined using the Affymetrix GeneChip miRNA Arrays analyzed using expression console 1.3 software. Validation of significantly dysregulated miRNA was confimed by quantitaive real-time PCR. The web-based DNA Intelligent Analysis (DIANA)-miRPath v2.0 was used to perform enrichment analysis of differentially expressed (DE) miRNA gene targets in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway.

Results

The pathologic evaluation revealed one benign (benign non-teratoid, n=1) and six malignant tumors (malignant teratoid, n=2; malignant non-teratoid, n = 4). A total of 88 miRNAs were upregulated and 43 miRNAs were downregulated significantly (P<0.05) in the tumor specimens. Many of these significantly dysregulated miRNAs were known to play various roles in carcinogenesis and tumor behavior. RT-PCR validated three significantly upregulated miRNAs and three significantly downregulated miRNAs namely miR-217, miR-216a, miR-216b, miR-146a, miR-509-3p and miR-211. Many DE miRNAs that were significant in ME tumors showed dysregulation in retinoblastoma, glioblastoma, and precursor, normal and reactive human cartilage. Enriched pathway analysis suggested a significant association of upregulated miRNAs with 15 pathways involved in prion disease and several types of cancer. The pathways involving significantly downregulated miRNAs included the toll-like receptor (TLR) (p<4.36E-16) and Nuclear Factor kappa B (NF-κB) signaling pathways (p<9.00E-06).

Conclusions

We report significantly dysregulated miRNAs in intraocular ME tumors, which exhibited abnormal profiles in other cancers as well such as retinoblastoma and glioblastoma. Pathway analysis of all dysregulated miRNAs shared commonalities with other cancer pathways.

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.

New insights into the development of infantile intraocular medulloepithelioma

PURPOSE

To define the maturational sequence of 3 infantile intraocular medulloepitheliomas.

DESIGN

Retrospective clinicohistopathologic and immunohistochemical study.

METHODS

Immunoreactivity of paraffin sections for CRX (cone-rod homebox transcription factor) and NeuN (biomarker for neuronal differentiation) were investigated together with other biomarkers, including S100, glial fibrillary acidic protein, epithelial membrane antigen, and various cytokeratins.

RESULTS

Three infants (aged 1, 6, and 8 months) had iris neovascularization, 2 had anterior ciliary body tumors, and 1 a posterior tumor associated with a retinochoroidal coloboma. Each tumor displayed a premedullary monolayer of cuboidal epithelium that was S100(+), NeuN(-), and CRX(-) and that transitioned into a multilaminar medullary epithelium forming neurotubules with adluminal cells that were CRX(+). NeuN first appeared in ablumenal neurotubular cells in 1 tumor and was also discovered among neuroblast-appearing cells in another. The third tumor associated with a coloboma was CRX(-) and NeuN(-).

CONCLUSIONS

A simple premedullary epithelial monolayer appears to be the fundamental source for the tumor and its multilaminar medullary epithelium. CRX(+) and NeuN(+) cells within the multilayered medullary layer approximate expression patterns similar to those found in retinal development and differentiation. Discovery of these biomarkers in the neoplastic ciliary epithelium in a small number of tumors indicates preliminarily that the most anterior layers of the optic cup have a retained retinal and neuroglial differentiation potentiality. The third case was CRX(-) and NeuN(-) and possibly arose from embryonic pigment epithelium at the edge of the retinochoroidal coloboma. These immunohistochemical findings offer histogenetic and potential diagnostic insights.

Neovascular glaucoma in a child: an unusual presentation of medulloepithelioma

A healthy 12 month old infant without significant medical history presented with left eye redness for one week. Ophthalmic examination showed elevated intraocular pressure with iris neovascularization in the affected eye with increased optic nerve cupping. Scleral depression revealed a ciliary body mass in the supratemporal quadrant. A large, non-pigmented, vascular mass was noted; biopsy results showed multilayered cords, tubules, and sheets resembling primitive medullary epithelium arising from the ciliary body. The patient was diagnosed with medulloepithelioma. The patient underwent enucleation of the affected eye. Medulloepithelioma is a rare but important cause of neovascular glaucoma in the pediatric population. This case will focus on the characteristics of medulloepthelioma and the differential diagnosis for a non-pigmented ciliary body mass in a child.

Peripheral medulloepithelioma: a rare tumor with a potential target therapy

Background

Medulloepithelioma (ME) is a rare embryonal tumor predominantly located in the eye or in the central nervous system without an established treatment.

Case presentation

We report of a case of a localized peripheral ME treated with conventional and high dose chemotherapy, surgery and local radiotherapy. At relapse, the tumor tissue revealed a different molecular signature compared to the initial tumor mass. This molecular signature revealed a high expression of platelet derived growth factor receptor (PDGFR). Sorafenib plus irinotecan and temozolomide was started with a 5 month progression free survival.

Conclusion

Our experience suggests a possible role of sorafenib or different PDGFR inhibitors in ME. Targeting treatment could represent an adjuvant and/or alternative therapy for ME and other rare tumors.

Ocular glioneuroma with medulloepitheliomatous differentiation in a goldfish (Carassius auratus)

An intraocular mass in the left eye causing chronic severe exophthalmia in an adult female goldfish ( Carassius auratus) is described. The fish shared an aquarium with another goldfish found dead with gross and microscopic lesions consistent with mycobacteriosis. Histological examination of the left eye, histochemical (periodic acid–Schiff [PAS], Alcian blue, Ziehl–Neelsen) and immunohistochemical tests (glial fibrillary acidic protein, human neuronal protein, vimentin, and cytokeratin AE1/AE3) were carried out on the intraocular mass. Neoplastic cells forming an unencapsulated highly cellular proliferation partially covered by an intact corneal epithelium were stained with Alcian blue, which demonstrated an abundant hyaluronic acid–rich extracellular matrix. Multifocally, there were cyst-like dilatations bordered by neuroepithelial cells, which were PAS-positive. The complex neoplastic proliferation was composed of glial-like cells, neuronal-like cells (immunoreactive to glial fibrillary acidic protein and human neuronal protein, respectively) and neuroepithelium, which suggested a retinal origin.

Imaging features of medulloepithelioma: report of four cases and review of the literature

BACKGROUND

Intraocular medulloepithelioma is a childhood tumor arising from the nonpigmented primitive ciliary neuroepithelium. Although rarer than retinoblastoma, it remains the second most common primary intraocular neoplasm in children. The rarity of intraocular medulloepithelioma creates the challenge in establishing a clinical diagnosis, and radiologically the tumor is often confused with other intraocular masses.

OBJECTIVE

To describe the clinical, imaging and pathological features of intraocular medulloepithelioma with emphasis on the role of imaging to enable its differentiation from more common intraocular pathology.

MATERIALS AND METHODS

We retrospectively analyzed the clinical, histopathological and imaging data of four children with intraocular medulloepithelioma.

RESULTS

All four children had medulloepithelioma arising from the ciliary body. The children were imaged with US (n = 3), MRI (n = 4), whole-body (99m)Tc-MDP scintigraphy (n = 2) and CT (n = 1). All four children had enucleation of the involved eye. One tumor was a malignant teratoid variant, two tumors were malignant nonteratoid variants and one was a nonteratoid variant of uncertain malignant potential. None of the tumors had extraocular extension on histopathology or imaging. Two children had associated retinal detachment on US and MRI examinations. All tumors were iso/hyperintense to vitreous on T1-weighted and hypointense on T2-weighted MRI and showed marked contrast enhancement of the solid components. No calcifications were identified on US or CT examinations.

CONCLUSION

Our findings are consistent with previously reported cases of medulloepithelioma. This series emphasizes the roles of various imaging modalities, with pathological correlation, in differentiating the tumor from other ciliary body masses, in detecting tumor extension and in identifying associated ocular complications. In this series we also describe the results of postsurgical follow-up for tumor recurrence.

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

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

Mechanisms controlling arrangements and movements of nuclei in pseudostratified epithelia

During development, cells undergo complex rearrangements that contribute to the final tissue architecture. A characteristic arrangement found in rapidly expanding, highly proliferative tissues is pseudostratified epithelium, which features notably elongated cells with varied nuclear positions along the cell axis. Although anomalies in its structure are implicated in diseases like microcephaly, how pseudostratification is formed and maintained remains elusive. In this review, we focus on a typical feature of pseudostratified epithelia called interkinetic nuclear migration (INM), which describes dynamic movements of nuclei within the elongated cell bodies. We provide an overview of cytoskeletal components underlying INM in different systems, discuss current understanding of its kinetics and timing, and evaluate how conflicting results could be explained through developmental and evolutionary considerations.