Intravitreal injection of melphalan for intraocular retinoblastoma

To investigate the safety and efficacy of intravitreal injection of melphalan for retinoblastoma.

A retrospective chart review of all patients who were administered intravitreal injections of melphalan for retinoblastoma between 1990 and 2011. A total of 264 eyes of 250 patients were included. All ocular adverse events, systemic prognosis, ocular prognosis, and visual acuity were investigated.

The total number of intravitreal injections administered was 1,067; each eye received between one and 25 injections. A postoperative subconjunctival tumor developed in one eye. None of the eyes suffered infections or uveitis, and all other adverse events including chorioretinal atrophy displayed incidences of less than 1.5 %. At 5 postoperative years, the cumulative incidence of cataract surgery was 3.1 % among the eyes that were treated without ocular hyperthermia. Distant metastasis or intracranial invasion occurred in 11 patients, all of whom had high-risk pathological factors for metastasis such as optic nerve invasion, but refused to receive adjuvant chemotherapy. Sixty-eight percent of the eyes achieved complete vitreous seed remission, but recurrence occurred in 19 % of these eyes after 10.0 ± 4.9 months. In addition, 47 and 27 % of the eyes without primary macular tumors retained visual acuity of >0.5 and >1.0, respectively.

The risk of extraocular tumor spreading following intravitreal injections is low, and other adverse events are rare. Sixty-eight percent of the treated eyes achieved complete vitreous seed remission, and about half of them retained practical levels of vision. The intravitreal injection of melphalan is a safe and effective treatment for vitreous seeds.