Pigmented malignant medulloepithelioma of the ciliary body

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.

Pigmented ciliary body medulloepithelioma in a newborn infant

Ciliary body medulloepithelioma is a nonpigmented tumor which presents during the first decade of life. It is rarely seen in newborn infants. We report a pigmented medulloepithelioma in a newborn infant, which showed a rapid growth. Ciliary body medulloepithelioma should be considered in the differential diagnosis in a newborn infant presenting with leukocoria.

TUMORS OF THE NONPIGMENTED EPITHELIUM OF THE CILIARY BODY: The Lorenz E. Zimmerman Tribute Lecture

BACKGROUND

In 1970, Dr. Lorenz Zimmerman delivered the Norman McAlister Gregg Lecture entitled "The remarkable polymorphism of tumors of the ciliary epithelium." Therein, he proposed a classification of these tumors that included congenital lesions (mainly medulloepithelioma) and acquired lesions (mainly adenoma and adenocarcinoma). The classification was based on histopathologic observations without detailed clinical information.

METHODS

Review of the published literature and personal experience with tumors of the nonpigmented ciliary body epithelium.

RESULTS

Since 1970, further observations through clinical examination and advanced testing with ultrasound biomicroscopy, anterior segment optical coherence tomography, and magnetic resonance imaging have expanded our knowledge regarding tumors of the nonpigmented ciliary body epithelium. Regarding medulloepithelioma, we have learned of the common associated features of neovascular glaucoma, retrolenticular neoplastic or vascular cyclitic membrane, intralesional cysts, response to radiotherapy, and association with Dicer-1 mutation. Regarding adenoma/adenocarcinoma, improved management with surgical resection (sparing globe) can be achieved. Fuchs adenoma, also termed coronal adenoma, is commonly found histopathologically, despite its rare clinical visualization, and should be added to the Zimmerman classification.

CONCLUSION

Since Zimmerman's report on histopathologic features of tumors of the nonpigmented ciliary body epithelium, there have been numerous publications and further observations on the clinical features and management of these intriguing neoplasms.

Intraocular Medulloepitheliomas and Embryonal Tumors With Multilayered Rosettes of the Brain: Comparative Roles of LIN28A and C19MC

PURPOSE

To compare immunohistochemical and genetic overlaps and differences between intraocular medulloepitheliomas and embryonal tumors with multilayered rosettes of the brain.

DESIGN

Retrospective histopathologic, immunohistochemical, and genetic analysis of 20 intraocular medulloepitheliomas.

METHODS

(1) Review of clinical data and hematoxylin-eosin-stained sections with (2) immunohistochemical staining of paraffin sections using a polyclonal antibody against the protein LIN28A, and (3) fluorescence in situ hybridization (FISH) testing for the amplification of the genetic locus 19q13.42 involving the C19MC cluster of miRNA. Ten retinoblastomas served as controls and to determine the specificity of these biomarkers for intraocular medulloepitheliomas.

RESULTS

Nineteen of the 20 intraocular medulloepitheliomas were either diffusely or focally LIN28A positive (weak, moderate, or strong). The most intense positivity correlated with aggressive behavior such as intraocular tissue invasion or extraocular extension. None of the cases studied by FISH harbored an amplicon for C19MC. The 10 retinoblastomas were LIN28A and C19MC negative.

CONCLUSION

LIN28A has a putative role in oncogenesis and is found only in embryonic cells and malignancies. Intraocular medulloepitheliomas and embryonal tumors with multilayered rosettes of the brain both display LIN28A positivity. Only the latter, however, display amplification of the 19q13.42 locus involving C19MC, implying that other causative factors are at play in intraocular medulloepitheliomas. More aggressive tumor behavior within the eye can be partially predicted by LIN28A staining intensity.

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.

Pigmented malignant teratoid medulloepithelioma of ciliary body - An extremely rare intraocular tumor in adult

Malignant teratoid medulloepithelioma of ciliary body is an extremely rare tumor usually occurring in children younger than 5 years of age and is usually amelanotic. Here, we report a very rare case of pigmented malignant teratoid medulloepithelioma in a 20-year old male patient who presented initially with pain, redness and proptosis of right eyeball. The right eyeball was enucleated. A histopathological diagnosis of orbital teratoma was made and no further treatment was given. Four months later, the patient developed another swelling in the same area. A review of the previous histopathology slides revealed a pigmented malignant teratoid medulloepithelioma. No nerve involvement was seen. MRI did not show any intracranial extension. The mass along with rest of the orbital tissue was removed. No adjuvant chemotherapy or radiotherapy was given due to the lack of intracranial extension. The patient was symptom free at 2-year follow-up and the repeat MRI also showed no evidence of recurrence.

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.