• Ocular Pathology/Oncology

    This international retrospective study evaluated the risk of extraocular extension in retinoblastoma patients after intravitreal chemotherapy.

    Study design

    Researchers reviewed medical records from 655 patients who received intravitreal chemotherapy injections at 10 international retinoblastoma centers during an 18-year period.


    Between 1999 to 2017, 3,553 intravitreal injections of melphalan, topotecan, or methotrexate were administered to 704 eyes of 655 patients. There were no cases of extraocular extensions throughout the study period.

    All clinics used at least 2 safety measures to reduce extraocular extensions, with 8 centers using 3 or more. These precautions included lowering IOP (pre-injection ocular massage and/or paracentesis), cryotherapy, ocular surface irrigation, ultrasound biomicroscopy surveillance of injection sites and subconjunctival chemotherapy.

    Based on the sample size, the authors estimate that the risk of extraocular extension in patients receiving intravitreal injections is no greater than 0.08%. 


    In addition to the limiting nature of retrospective studies, investigators did not disclose the average follow-up time. 

    Clinical significance

    Findings from this large, multicenter study show that extraocular extension of retinoblastoma is unlikely when using least 2 prophylactic techniques