RESUMEN
Objective: Description of melphalan's toxicity in retinoblastoma treatment. Methods: Clinical case report. Results: We presented a case of unilateral retinoblastoma with vitreous seeding at diagnosis, in which the use of intravitreal melphalan produced many adverse reactions. Conclusions: Vitreous seedings have been one of the most important challenges in retinoblastoma treatment. Intravitreal melphalan has achieved the regression of vitreous seedings in a large percentage of cases. It is a safe treatment; however, it can produce toxicity, even with the standard dose of 20-30 µg, which has been poorly documented. Exhaustive follow-up of patients is recommended for an early diagnosis of possible adverse effects. Abbreviations: OS = left eye, RI = magnetic resonance imaging, OCT = optical coherence tomography.