There were 2 boys and 2 girls in the study group; their ages at treatment were 6 months, 5 months, 15 months, and 19 months. One child had a family history of retinoblastoma and all had bilateral disease at initial diagnosis. The macula was involved with the tumor in all cases. Pretreatment electroretinography (ERG) was performed on 6 of the 8 eyes; flicker potentials were 22.1 μV, 22.4 μV, 33.4 μV, 71.7 μV, and 105.5 μV, and “barely detectable” in 1 case. Follow-up ranged from 8 to 17 months (mean, 12.75 months), and 2 of the patients were followed up for more than 1 year. Melphalan was used alone in 2 patients and melphalan plus topotecan was used in 2 patients. Sessions were performed at 3- to 4-week intervals, and the total number of sessions ranged from 1 to 3 (mean, 2.5). One patient had only 1 session. No patient received external beam radiation or plaque therapy. The total doses of melphalan per tandem session (adding the dose from the right and left eyes) was 4 mg in 1 session, 5 mg in 8 sessions, and 5.5 mg in 1 session; for topotecan, doses were 0.3 mg in 3 sessions, 0.5 mg in 1 session, and 1 mg in 1 session. Topotecan was added for the eyes with more advanced disease.