Outcomes of Intravenous Chemotherapy (Chemoreduction) for Retinoblastoma Based on Patient Age in 964 Eyes of 554 Patients.

Abstract

To evaluate retinoblastoma control after intravenous chemotherapy (chemoreduction) by patient age at presentation. Retrospective case series. This study included 964 eyes of 554 patients treated with chemoreduction at Ocular Oncology Service at Wills Eye Hospital. Patients received 6 monthly cycles of standard chemoreduction. Additional therapies for tumor control were performed as needed. Of 964 eyes, a comparison by age group (<6 months vs. 6-12 months vs. 13-24 months vs. >24 months) revealed more advanced age group with higher frequency of group E tumor (15% vs. 25% vs. 32% vs. 39%, P < 0.001). By treatment outcomes, complete tumor control was achieved with chemoreduction alone more often in less advanced age group (46% vs. 30% vs. 17% vs. 8%, P < 0.001). Additional treatment after chemoreduction was needed more often in more advanced age group with external beam radiotherapy (EBRT; 9% vs. 16% vs. 20% vs. 15%, P = 0.006) or enucleation (12% vs. 18% vs. 26% vs. 37%, P < 0.001). Over time (1994-1998 vs. 1999-2003 vs. 2004-2008 vs. 2009-2013 vs. 2014-2019), the paradigm for additional required treatment after chemoreduction shifted toward less EBRT (27% vs. 24% vs. 14% vs. 7% vs. 2%, P < 0.001) and more intra-arterial (0% vs. 0% vs. 1% vs. 25% vs. 48%, P < 0.001) and intravitreal (0% vs. 0% vs. 3% vs. 10% vs. 20%, P < 0.001) chemotherapy. Chemoreduction is a safe and effective treatment method for patients with retinoblastoma, demonstrating the best tumor control in the younger age groups.