Long-Term Outcomes of Group B Eyes in Patients with Retinoblastoma Treated with Short-Course Chemoreduction: Experience from Children's Hospital Los Angeles/University of Southern California

Abstract

Background/Aims: Chemoreduction protocols for retinoblastoma vary widely across institutions. Herein, we compare a 3- versus 6-cycle chemotherapy approach for group B retinoblastoma. Methods: A nonrandomized, retrospective review of patients diagnosed with group B retinoblastoma from 1991-2011 at Children's Hospital Los Angeles was performed. A total of 72 eyes of 63 patients were analyzed. Mean follow-up time was 82 months (range 6-272 months). Main outcome measures were globe salvage and need for external beam radiation. Results: Forty-six patients (55 eyes) were treated upfront with 3 cycles of carboplatin, etoposide, and vincristine; 17 patients (17 eyes) received 6 cycles. Thirty-seven eyes (67%) in the 3-cycle group were cured with initial chemoreduction alone. An additional 10 eyes with persistent or recurrent tumors were rescued with 3 more cycles for a total salvage rate of 85% (47/55 eyes). In the 6-cycle group, 16 of 17 eyes (94%) avoided radiation and enucleation. Conclusion: The initial recurrence rate was higher for the 3-cycle group (p = 0.03). However, eyes failing short-course chemoreduction were rescued with 3 additional cycles and achieved a similar overall event-free survival rate (p = 0.16). In our cohort, this short-course approach spared 63% (29/46) of patients with group B retinoblastoma the extra 3 cycles of systemic chemotherapy.

Risk of metastasis and orbital recurrence in advanced retinoblastoma eyes treated with systemic chemoreduction versus primary enucleation

“…It has been theorized that treatment with systemic chemoreduction may decrease the incidence of trilateral disease developing in a predisposed population (e.g., those with germline mutations in the retinoblastoma gene) . One patient in our series was treated with primary enucleation for a Group E eye and three cycles of systemic chemoreduction for the contralateral Group B eye . In this single case, the three cycles were not protective against the development of a pinealoblastoma.…”

“…Systemic chemoreduction consists of intravenous carboplatin 780 mg/m 2 (13 mg/kg for children <36 months) × 2 days, etoposide 150 mg/m 2 (5 mg/kg for <36 months) × 2 days, and vincristine 1.5 mg/m 2 (0.05 mg/kg for <36 months) × 1 day, for 6 cycles every 28 days (i.e., CEV). Infants less than 6 months of age at diagnosis receive a modified dosing regimen with a 50% decrease in all agents for the first cycle, with subsequent doses modified by clinical response and toxicity . At our institution, vincristine is omitted for patients less than 2 months of age due to concern for paralytic ileus.…”

Optic Nerve Obscuration in Retinoblastoma: A Risk Factor for Optic Nerve Invasion

“…Globe salvaging treatment for Group E retinoblastoma is done only if the patient has bilateral disease wherein the contralateral eye will also require systemic therapy for salvage. The treatment paradigms at our center have been described previously [9,10,11]. …”

Posterior Vitreous Detachment and the Associated Risk of Retinal Toxicity with Intravitreal Melphalan Treatment for Retinoblastoma

“…In brief, Group B eyes are treated with 3 cycles [18], Group C eyes with 4–6 cycles, and Group D and E eyes with 6 cycles of intravenous chemoreduction. Infants < 6 months of age at diagnosis receive a modified dosing regimen, which has been described [19].…”