Retinocytoma characterized by four characteristic features

Retinocytoma is a rare benign tumor with characteristic clinical features. Arun Singh, MD, director, Department of Ophthalmic Oncology, Cole Eye Institute, Cleveland, OH, United States, described how to differentiate this retinal pathology from other pathologies.

The differential diagnosis should include toxoplasmosis and trauma, according to Dr. Singh, who also emphasized the importance of a family history of retinoblastoma and retinocytoma.

The most important diagnostic feature of retinocytoma is the presence of a translucent retinal mass, which occurs in 90%; other frequent features are calcification, and retinal pigment epithelial changes, and chorioretinal atrophy.

"These are the four hallmark features of the disease," he said.

The tumor is diagnosed in five clinical settings, according to Dr. Singh.

"The clinical settings that prompt a diagnosis of retinocytoma are that it is sporadic condition, it occurs in patients with apparently normal parents who have multiple children with retinocytoma, it occurs in association with retinoblastoma in the same or the fellow eye, it occurs in a child with a small or medium-sized tumor that is unresponsive to chemotherapy and does not grow, and it occurs in the setting of low penetrance retinoblastoma," Dr. Singh said.

The mechanisms of retinocytoma are not clear. Dr. Singh suggested that it might stop at the N2 level and not fully transform into retinoblastoma.

"This retinal pathology is usually single, the tumor should always be suspected when two siblings have retinoblastoma, it is rare to have trilateral disease, there are four common clinical features, and there are five clinical settings in which retinocytoma can occur," Dr. Singh summarized.