The role of chemotherapy in orbital involvement of retinoblastoma. The experience of a single institution with 33 patients.

Abstract

Orbital involvement is a rare occurrence in retinoblastoma but still carries a bad prognosis. The aim of this study was to define more clearly the role of chemotherapy in this advanced disease. Between 1977 and 1991, 33 patients were treated at the Services de Pédiatrie at Institut Curie (Paris, France) for orbital involvement of retinoblastoma, which was isolated in 20 patients and associated with metastases in 13 patients (outside the central nervous system [CNS], 6; within the CNS, 7). Treatment included chemotherapy for 33 patients, irradiation of the orbit for 23 patients, and intrathecal chemotherapy and/or CNS irradiation in selected patients. The plateau phase of the survival curve was reached at 15 months, with a survival of 34% plus or minus 8%. The disease free interval was longer when patients had no CNS disease (P < 0.05). Twenty of the 21 recurrences (95%) occurred within 1 year after diagnosis of orbital involvement. Intensive chemotherapy using cyclophosphamide, platinum compounds, epipodophyllotoxins, doxorubicin, and vincristine was effective in orbital involvement of retinoblastoma even with associated extra-CNS metastases. However, associated CNS disease still carries a bad prognosis, and long term follow-up is necessary to evaluate the risk of a second tumor.