Outcomes of a two-drug chemotherapy regimen for retinoblastoma

Abstract

9064 Background: Retinoblastoma is the most common intraocular tumor of childhood in the U.S. and has an overall survival rate of over 90%. The optimal treatment regimen for intraocular retinoblastoma has not yet been established. Current treatment regimens for retinoblastoma involve combinations of chemotherapy with focal therapy. We report here the results of an institutional retinoblastoma treatment trial to determine the vision- and globe-salvage rates and associated toxicity of a regimen combining carboplatin and etoposide with focal therapy. Methods: 29 patients diagnosed with either bilateral retinoblastoma or unilateral retinoblastoma in infants under 12 months of age were treated prospectively with carboplatin and etoposide plus focal therapy between 1992 and 2004 at Children’s Memorial Hospital in Chicago. External beam radiation therapy (EBRT) and enucleation were utilized as needed. Results: The regression rate after 6 cycles of chemotherapy was 85.4%. 7 eyes received EBRT and 22 eyes were enucleated. The overall vision salvage rate without EBRT was 50%, with a vision salvage rate of eyes with Reese-Ellsworth (R-E) groups I-IV tumors of 82.6%. The vision salvage rate of eyes with R-E group V tumors was 20%. The vision salvage rate for eyes with Murphree groups A and B was 77.3%, but only 26.9% for groups C and D. The 10-year estimated EBRT/enucleation-free survival rate was 47%. There were no treatment related mortalities and minimal long-term side effects, with one case of secondary malignancy. Conclusions: The combination of carboplatin and etoposide with focal therapy is a well-tolerated regimen that avoids EBRT and has acceptable vision salvage rates for R-E groups I-IV and Murphree groups A and B retinoblastoma. Patients with R-E group V and Murphree groups C and D retinoblastoma do less well with chemotherapy and require more intensive or novel approaches to therapy. No significant financial relationships to disclose.