Long-term outcomes of Group D eyes in bilateral retinoblastoma patients treated with chemoreduction and low-dose IMRT salvage.

BACKGROUND: To evaluate outcomes of Group D eyes of bilateral retinoblastoma patients treated with primary chemoreduction and external beam radiation as salvage. PROCEDURE: Retrospective chart review of patients diagnosed with bilateral retinoblastoma and designated Group D in at least one eye from January 1, 2000 to December 31, 2009. Overall, 62 Group D eyes of 49 patients were included; 13 had bilateral Group D disease. Primary chemoreduction with vincristine, etoposide, and carboplatin with local consolidation was administered, followed by external beam radiation in the form of intensity-modulated radiation therapy (IMRT) as salvage for recurrent tumor. Primary outcome measure was globe salvage.
RESULTS: Of 62 Group D eyes, 7 were enucleated primarily; 55 were treated with systemic chemoreduction, and local therapy. Chemoreduction cured 26 of 55 eyes (47%). Recurrences were found in 29 eyes; 5 underwent enucleation and 24 were treated with IMRT at a dose of 24 Gy (2 eyes) or 36 Gy (22 eyes). Of the 24 irradiated eyes, 19 (79%) were salvaged and 5 required enucleation. Final visual acuity ranged from 20/20 to light perception with 10 eyes having 20/80 or better visual acuity. Average follow-up was 54.2 months.
CONCLUSION: Kaplan-Meier estimates of eye survival of Group D eyes in bilateral patients at 12 months is 82% (95% confidence interval [CI] 70.1-89.7%); at 60 months eye survival is estimated to be 68% (95% confidence interval [CI] 55.4-82.8%). Systemic treatment for retinoblastoma demonstrated a high rate of globe preservation with acceptable complications and many eyes retaining functional vision.