Observations on 17 Patients With Retinocytoma

OBJECTIVE: To study the clinical features and natural history of 17 patients with retinocytoma. DESIGN: A retrospective case series. SETTING: Tertiary referral center. PATIENTS: Data on 17 patients with retinocytoma were reviewed for clinical features. The natural history of retinocytoma and its risk for malignant transformation were also evaluated. RESULTS: Among 920 consecutive patients who had retinoblastoma, retinocytoma, or both, we identified 24 tumors in 17 patients (1.8%) with clinical features compatible with retinocytoma. The median age at diagnosis was 15 years (range, 4-45 years). Of the 24 tumors, the retinocytoma was bilateral in 3 cases (13%) and the family history of retinoblastoma was positive in 3 cases (13%). Seventeen (71%) of the tumors were extramacular in location, and 7 (29%) were located in the macular area. Ophthalmoscopic features characteristic of retinocytoma included the presence of a translucent retinal mass in 21 (88%), calcification in 15 (63%), and retinal pigment epithelial alteration in 13 (54%) of the 24 tumors. A combination of all 3 features was observed in 8 (33%) of the 24 tumors. In 13 (54%) of the tumors, a zone of chorioretinal atrophy could be observed. In 1 patient, subtle tumor regression was documented photographically. Only 1 retinocytoma (4%) underwent malignant transformation into retinoblastoma. At the last follow-up visit, none of the patients had developed a pineoblastoma or another second malignant neoplasm. CONCLUSIONS: Retinocytoma is a rare benign retinal tumor that has characteristic clinical features. The areas of chorioretinal atrophy were suggestive of tumor regression. In our series, the risk for malignant transformation of retinocytoma into retinoblastoma was 4%; therefore, patients with a presumed diagnosis of retinocytoma should be closely observed.