Malignant Teratoid Medulloepithelioma with Rhabdomyosarcomatous Differentiation

Area of Science:

• Ophthalmology
• Pathology
• Oncology

Background:

• Intraocular malignant teratoid medulloepithelioma is a rare and aggressive eye tumor.
• Understanding its clinicopathologic features and genetic underpinnings is crucial for diagnosis and treatment.

Purpose of the Study:

• To identify and report the clinicopathologic features of two cases of intraocular malignant teratoid medulloepitheliomas.
• To investigate the presence of rhabdomyosarcomatous differentiation and DICER1 mutations in these tumors.

Main Methods:

• Review of clinical and pathological findings in two patients who underwent enucleation for intraocular tumors.
• Routine eye sectioning and immunohistochemical staining (neuron-specific enolase, S-100, desmin, myogenin).
• Mutational analysis for DICER1 mutations.

Main Results:

• Two pediatric female patients (ages 3 and 14) presented with intraocular tumors filling the posterior compartments.
• Tumors showed both neuroepithelial (NSE, S-100 positive) and mesenchymal (rhabdoid cells, desmin, myogenin positive) components.
• Both tumors harbored DICER1 mutations and were classified as malignant teratoid medulloepithelioma with rhabdomyosarcomatous differentiation.

Conclusions:

• Intraocular medulloepitheliomas can exhibit rhabdomyosarcomatous differentiation.
• DICER1 mutations are associated with this specific subtype of intraocular tumor.