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Updated: Apr 21, 2026
Establishment and Propagation of Human Retinoblastoma Tumors in Immune Deficient Mice
Published on: August 4, 2011
Malignant transformation of retinocytoma into retinoblastoma
Yusuf Uysal1, Carol L Shields, Jerry A Shields
1From the *Ocular Oncology Service and the †Department of Pathology, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania.
Purpose:
To describe presumed malignant transformation of a single retinocytoma into retinoblastoma in a child with multifocal retinocytomas.
Methods:
A 7-year-old boy presented with a white fundus lesion in the left eye. Ophthalmic evaluation showed one retinocytoma (spontaneously regressed retinoblastoma/arrested retinoblastoma) in each eye and one active endophytic retinoblastoma in the left eye. The left eye was enucleated.
Results:
Histopathologic examination disclosed a small predominantly endophytic retinoblastoma with extensive vitreous seeding in association with a basal focus of well differentiated tumor with photoreceptor differentiation, suggestive of retinocytoma. The findings were consistent with malignant transformation of retinocytoma into retinoblastoma.
Conclusion:
Patients presumed to have retinocytoma at clinical evaluation should have lifelong follow-up for the remote possibility of malignant transformation.
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