Intravitreal chemotherapy may enable globe retention in retinoblastoma cases
Intravitreal chemotherapy may be used to control tumors in the presence of vitreous seeding in patients with retinoblastoma, a study found.
“The presence of vitreous and/or subretinal seeds in retinoblastoma at diagnosis significantly reduces the prognosis for tumor control and eye salvage. In such eyes, ocular survival barely reaches 50% when external beam radiotherapy is used as first-line treatment,” the study authors said.
The retrospective study included 23 eyes of 23 heavily pretreated patients who had retinoblastoma and active vitreous seeding. Median patient age at initial injection was 29 months.
All patients underwent intravitreal injection of 20 µm to 30 µm melphalan every 7 to 10 days. Patients received up to eight injections until complete seed fragmentation or complete response to treatment was observed.
An anterior chamber paracentesis was performed before injection, and 0.1 mL to 0.15 mL of aqueous fluid was drawn and subjected to cytopathological analysis.
A 32-gauge needle mounted on a tuberculin syringe was inserted perpendicularly 2.5 mm to 3.5 mm from the limbus at the meridian opposite the seeds and through the conjunctiva and sclera until the needle tip broached the center of the vitreous cavity.
Study results showed that vitreous seeding was localized in 13 eyes and diffuse in 10 eyes. Six eyes had subretinal seeding in addition to vitreous seeding.
Enucleation was avoided in 87% of cases. Complete remission was achieved in all retained eyes at a median follow-up interval of 22 months.
The estimated ocular survival rate at 2 years was 84.14%.