Risk Factors for Tumor Recurrence Following Primary Intravenous Chemotherapy (Chemoreduction) for Retinoblastoma in 869 Eyes of 551 Patients.

PURPOSE

To identify risk factors for retinoblastoma recurrence following chemoreduction.

METHODS

This was a retrospective review of patients with retinoblastoma treated from 1994 to 2019 using chemoreduction with analysis for recurrence using Kaplan-Meier, Cox regression, and logistic regression.

RESULTS

There were 869 eyes of 551 patients with retinoblastoma treated with chemoreduction. Follow-up in 556 eyes revealed main solid tumor recurrence (n = 355, 64%), subretinal seed recurrence (n = 244, 44%), vitreous seed recurrence (n = 162, 29%), and/or new tumor (n = 118, 21%) requiring management with focal therapy (transpupillary thermotherapy, cryotherapy) (n = 294, 53%), intra-arterial chemotherapy (n = 125, 22%), intravitreal chemotherapy (n = 36, 6%), plaque radiotherapy (n = 120, 22%), external beam radiotherapy (n = 57, 10%), and/or enucleation (n = 49, 9%). Of all recurrences, 62% were detected by 1 year, 86% by 2 years, 94% by 3 years, 98% by 5 years, 99% by 10 years, and 100% by 15 years. Risk factors for recurrence on multivariate analysis included younger patient age at presentation (odds ratio [OR] = 1.02 [1.00 to 1.04] per 1 month decrease, P = .02), greater International Classification of Retinoblastoma group (OR = 1.24 [1.05 to 1.47] per 1 more advanced group, P = .01), shorter tumor distance to optic disc (OR = 1.11 [1.01 to 1.21] per 1 mm decrease, P = .03), and presence of subretinal seeds (OR = 1.66 [1.09 to 2.53], P = .02).

CONCLUSIONS

Retinoblastoma recurrence after chemoreduction is usually detected within the first 3 years following treatment. Younger patients with more advanced, posteriorly located tumors and subretinal seeds at presentation are at increased risk, but recurrence can often be managed with globe-sparing therapy. [J Pediatr Ophthalmol Strabismus. 2020;57(4):224-234.].