Systemic neoadjuvant chemotherapy for Group B intraocular retinoblastoma (ARET0331): A report from the Children’s Oncology Group

Systemic neoadjuvant chemotherapy for Group B intraocular retinoblastoma (ARET0331): A report from the Children’s Oncology Group
Group B retinoblastoma currently treated with systemic chemotherapy (carboplatin, vincristine, etoposide) and local ophthalmic therapies with the goal of avoiding enucleation and external beam radiation and the long term morbidity and mortality associated with these therapies. However, patients still exposed to etoposide thus concerns about secondary leukemia. Goal of this study was to demonstrate that the removal of etoposide would not significantly alter EFS.
Multicentre, single arm trial comparing the 2-year EFS of vincristine and carboplatin compared to the historical 2-year EFS of 96% with 3 drug therapy. Twenty-one patients (25 eyes) were treated with six cycles of VC, accompanied by local ophthalmic therapies after cycle 1. All examinations under anaesthesia were reviewed centrally to confirm group B retinoblastoma.
All patients had tumor regression after the first cycle of VC and only two patients had progression during therapy. There were seven treatment failures resulting in a 2-year EFS of 65% and early study closure in accordance with the statistical design. All treatment failures were local and salvaged with additional therapy (OS 100%). The 2-year cumulative incidence of enucleation and radiation therapy was 15% and 10% respectively. Suggested explanations for altered EFS were removal of etoposide, multicentre study (instead of single institution w/ significant retinoblastoma expertise), or due to delay of local ophthalmic therapy until after cycle 1.
Single arm study of small cohort with short follow up.
Removal of etoposide in treatment of Group B intraocular retinoblastoma resulted in worse EFS compared to 3 drugs, however OS was 100%.