Malignant transformation of retinocytoma into retinoblastoma.
OBJECTIVE
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.


CONCLUSIONS
Patients presumed to have retinocytoma at clinical evaluation should have lifelong follow-up for the remote possibility of malignant transformation.
From the *Ocular Oncology Service and the †Department of Pathology, Wills Eye Hospital, Thomas Jefferson University, Philadelphia, Pennsylvania.
Yusuf
Y
Uysal
Carol L
CL
Shields
Jerry A
JA
Shields
Ralph C
RC
Eagle