Malignant teratoid medulloepithelioma with retinoblastic and rhabdomyoblastic differentiation

• Published in: Journal of AAPOS Vol. 17; no. 3; pp. 328 - 331
• Main Authors: Earl, James B., MD, PhD, Minckler, Don S., MD, MS, Lee, Thomas C., MD, Murphree, A. Linn, MD
• Format: Journal Article
• Language: English
• Published: United States Mosby, Inc 01.06.2013
• Subjects: Biomarkers, Tumor - analysis; Biopsy, Fine-Needle; Cell Differentiation; Diagnosis, Differential; Eye Enucleation; Female; Gestational Age; Humans; Infant; Neoplasms, Neuroepithelial - chemistry; Neoplasms, Neuroepithelial - pathology; Ophthalmology; Persistent Hyperplastic Primary Vitreous - diagnostic imaging; Retinal Neoplasms - chemistry; Retinal Neoplasms - pathology; Retinoblastoma - chemistry; Retinoblastoma - pathology; Rhabdomyosarcoma - chemistry; Rhabdomyosarcoma - pathology; Tomography, X-Ray Computed; Ultrasonography
• ISSN: 1091-8531; 1528-3933
• DOI: 10.1016/j.jaapos.2013.02.005

We describe an unusual case of malignant teratoid medulloepithelioma in which distinct populations of tumor cells with different immunohistochemical staining patterns existed within the same eye. A neuroblastic population exhibited atypical features of retinoblastoma, including organization into pseudo-Flexner-Wintersteiner and Homer-Wright rosettes. Other populations evolved in strikingly different patterns, with large fields of cells resembling astrocytes and intervening streams of spindle cells that suggested smooth muscle. The spindle cell population was negative for smooth muscle antigen but stained positively for desmin, myoglobin, and myogenin. Under high magnification, the desmin, myoglobin, and myogenin-staining cells exhibited striations consistent with skeletal muscle differentiation.