Malignant teratoid medulloepithelioma manifesting as a black epibulbar mass with expulsive hemorrhage

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.

Pigmented malignant medulloepithelioma of the ciliary body

Medulloepitheliomas are usually amelanotic. Pigmented medulloepitheliomas are unusual and only two cases have been reported. We report an additional case of pigmented malignant medulloepithelioma of the ciliary body with histopathologic correlation.

Spontaneous expulsive suprachoroidal hemorrhage

PURPOSE

To present a 90-year-old patient with spontaneous expulsive suprachoroidal hemorrhage (SESCH). This unique case suggests a mechanism of SESCH, which is still under debate.

METHODS

The patient, who had corneal inflammatory disease and diabetes mellitus, atherosclerosis, and glaucoma, presented with active ocular bleeding and expulsion of intraocular tissues. Almost the entire cornea was absent, except for several small and irregular areas in its periphery. Histopathologic evaluation of the eviscerated contents was performed.

RESULTS

Clinicopathologic evaluation revealed acute inflammation of the corneal remains as well as intraocular inflammation. Inflammatory necrosis of choroidal vessels was evident.

CONCLUSION

The findings point to the assumption that choroidal bleeding, secondary to vascular inflammatory necrosis, was the initial event in this case of spontaneous expulsive suprachoroidal hemorrhage. Presumedly, the intraocular pressure level was very high owing to continuous bleeding, which could result in a very large, rather than localized, tearing of the peripherally inflamed cornea.

Bilateral ectopia lentis as a presenting feature of medulloepithelioma

Ectopia lentis may be a feature of numerous systemic and ocular disorders. Kivela and Tarkkanen described an 8-year-old girl with medulloepithelioma who presented with ectopia lentis and a mass behind the temporal iris. Shields reported 2 children with medulloepithelioma who had ectopia lentis associated with neovascular glaucoma. To date, there has been no report of a child with ectopia lentis as the only presentation of an intraocular tumor. We present 2 children with malignant medulloepitheliomas who presented in this fashion.

Congenital neoplasms of the nonpigmented ciliary epithelium (medulloepithelioma)

BACKGROUND

Most reports on intraocular medulloepithelioma have been single case descriptions. The authors reviewed ten patients with intraocular medulloepithelioma, discuss some little known clinical features of this entity, and make diagnostic and therapeutic recommendations.

PATIENTS AND METHODS

The records of the authors' patients with histopathologically confirmed medulloepithelioma were reviewed, and the clinical features, diagnostic problems, management, histopathology, and prognosis were assessed.

RESULTS

Of the ten patients, nine were children, ranging in age from 2 months to 10 years, and one patient was 58 years of age at the time of clinical presentation. In seven patients, there was a delay in diagnosis, ranging from 3 to 28 months, and four patients underwent surgery for cataract, glaucoma, or other secondary conditions while the tumor was unsuspected. All patients had a nonpigmented ciliary body mass and a notched or subluxated lens, and six had neovascular glaucoma and evident cysts in the mass. The authors' initial management was enucleation in four patients and local resection in six. Of the six patients managed by local resection, five eventually required enucleation, four because of local tumor recurrence and one because of ocular inflammation and discomfort. Pathologically, nine tumors were classified as malignant (5 teratoid, 4 nonteratoid) and one as benign. In one patient (the adult), metastasis to the parotid gland developed.

CONCLUSION

Intraocular medulloepithelioma generally occurs in the first decade of life as a nonpigmented ciliary body mass. It has a tendency to cause secondary neovascular glaucoma, a characteristic lens notch and subluxation, and a neoplastic cyclitic membrane. Enucleation is the best treatment for advanced cases. For smaller circumscribed lesions, local resection may be attempted, but such treatment is followed frequently by local recurrence. Although most medulloepitheliomas are cytologically malignant, distant metastasis is uncommon.

Central nervous system medulloepithelioma: a series of eight cases including two arising in the pons

Medulloepithelioma is an uncommon childhood tumor of the central nervous system (CNS) whose histopathological appearance has been confused with medulloblastoma and other childhood primitive neuroectodermal tumors (PNETs), but which has a vastly different clinical course. The authors have reviewed the clinical features and treatment responses of eight children with these rare tumors, the largest series to date. In this series, the medulloepitheliomas were equally distributed between supratentorial and infratentorial primary sites. Four patients underwent gross- or near-total resections, one patient's tumor was partially resected, and one patient had biopsy only. Biopsy and ablative surgery were not attempted in two children with pontine tumors. Treatment included both radiation and chemotherapy (four patients), radiation alone (one patient), chemotherapy alone (one patient), and no post-operative treatment (two patients). Six patients died with a mean survival of 10 months and two are disease free with neurological impairment. Both long-term survivors underwent gross-total resections of their tumors. Postmortem examination revealed diffuse CNS tumor dissemination in four patients. Medulloepithelioma, often confused with less aggressive PNETs, can mimic intrinsic brainstem glioma, responds poorly to treatment, and is prone to CNS dissemination at the time of tumor progression.

Dracunculiasis of the orbit and eyelid. Light and electron microscopic observations of two cases

Dracunculiasis, an infection caused by the nematode parasite, Dracunculus medinensis, usually affects the skin and subcutaneous tissue. The authors studied two cases of dracunculiasis involving the orbit and eyelid in African children. In the first case, the patient presented with proptosis and the clinical diagnosis was Burkitt's lymphoma. In the second patient, the eyelid lesion was diagnosed as a dermoid cyst. Histopathologically, the orbital lesion showed a degenerated and partially calcified worm within a large intraconal abscess. The eyelid lesion contained a well-preserved gravid female worm filled with larvae. The results of transmission and scanning electron microscopic studies are discussed.

Recurrent medulloepithelioma of the ciliary body. Immunohistochemical characteristics

A predominantly benign medulloepithelioma of the ciliary body was diagnosed in an 8-year-old girl and resected by iridocyclectomy. It recurred twice during 30 months. Highly malignant histopathologic features developed, and the eye finally perforated and had to be enucleated. No recurrence or metastases have subsequently developed. Histologically, the tumor was a nonteratoid medulloepithelioma consisting of elements resembling embryonic retina, nonpigmented ciliary epithelium, and neuroblasts, but had also areas of obvious glial and neuronal differentiation as judged by immunohistochemistry. The neuroepithelial tumor cells were positive for neuron-specific enolase, vimentin, and often for S-100 protein. The neuroblastic cells were generally positive for neuron-specific enolase and synaptophysin, but were intermixed with glia-like tumor cells positive for vimentin, glial fibrillary acidic protein, and S-100 protein. The results suggest that even a nonteratoid medulloepithelioma may be, unlike retinoblastoma, a truly multipotential tumor.