The Essential Role Of External Beam Radiation Therapy In The Management Of Advanced-Stage Retinoblastoma

Purpose/Objective(s)Retinoblastoma (RB), the most common intraocular malignancy in children, was historically treated with definitive external beam radiation therapy (EBRT). Over the last 15 years, chemoreduction with intensive focal therapy has been shown to achieve excellent control while avoiding radiation-induced morbidity and mortality (due to secondary malignancy). However in the setting of residual disease after enucleation or diffuse vitreous or subretinal seeding, EBRT still plays an important role. We evaluated our institutional long term outcomes for advanced stage RB in the setting of modern treatment techniques.Materials/MethodsThe charts of 31 patients (42 eyes) with RB, 22 of which had bilateral disease (11 receiving bilateral radiation therapy), who received EBRT from June 1992 to March 2012 were analyzed. Cox and logistic regression models were used to identify outcome predictors.ResultsThe median follow-up was 139 months. For the entire cohort, 10-year overall survival (OS) and progression free survival (PFS) were 89.5% and 78.7% respectively. The overall eye preservation rate (EPR) was 81.25% (6/32 eyes). Ten-year local control (LC) was 80.95%. Of the 42 eyes, 1 was Group III (Reese-Ellsworth), 3 were Group IV, and 38 were Group V. Twenty-eight eyes (67%) were treated with a relative lens sparing (RLS) technique. Ten eyes (24%) were treated with a modified lens sparing (MLS) technique. Four eyes were treated with other techniques: Electron beam = 1, I-125 eyeplaque = 1, and mixed beam = 2. Thirteen (31%) eyes received <45 Gy, and 29 (69%) received ≥45 Gy. Seventeen (55%) patients received chemotherapy. No difference in toxicity was found for either dose (OR = 0.76, 95% CI, 0.17-3.42, p = 0.72) or technique, comparing MLS vs RLS (OR = 1.87, 95% CI, 0.36-9.63, p = 0.46). No difference in EPR was found for either dose (OR = 2.25, 95% CI, 0.37-13.67, p = 0.38) or technique, comparing MLS vs RLS (OR = 2.57; 95% CI, 0.25-26.85, p = 0.43). Additionally, there was no difference in LC, PFS, or OS by radiation dose group. There was one radiation induced malignancy.ConclusionsPoster Viewing Abstract 3035; TableOutcomePrognostic factorsCategoryHR (95% CI)P valueLRRDose ≥4500Yes vs no1.80 (0.20, 16.11).599PFSDose ≥4500Yes vs no1.99 (0.24, 16.53).525OSDose ≥4500Yes vs no0.66 (0.11, 3.95).649 Open table in a new tab Purpose/Objective(s)Retinoblastoma (RB), the most common intraocular malignancy in children, was historically treated with definitive external beam radiation therapy (EBRT). Over the last 15 years, chemoreduction with intensive focal therapy has been shown to achieve excellent control while avoiding radiation-induced morbidity and mortality (due to secondary malignancy). However in the setting of residual disease after enucleation or diffuse vitreous or subretinal seeding, EBRT still plays an important role. We evaluated our institutional long term outcomes for advanced stage RB in the setting of modern treatment techniques. Retinoblastoma (RB), the most common intraocular malignancy in children, was historically treated with definitive external beam radiation therapy (EBRT). Over the last 15 years, chemoreduction with intensive focal therapy has been shown to achieve excellent control while avoiding radiation-induced morbidity and mortality (due to secondary malignancy). However in the setting of residual disease after enucleation or diffuse vitreous or subretinal seeding, EBRT still plays an important role. We evaluated our institutional long term outcomes for advanced stage RB in the setting of modern treatment techniques. Materials/MethodsThe charts of 31 patients (42 eyes) with RB, 22 of which had bilateral disease (11 receiving bilateral radiation therapy), who received EBRT from June 1992 to March 2012 were analyzed. Cox and logistic regression models were used to identify outcome predictors. The charts of 31 patients (42 eyes) with RB, 22 of which had bilateral disease (11 receiving bilateral radiation therapy), who received EBRT from June 1992 to March 2012 were analyzed. Cox and logistic regression models were used to identify outcome predictors. ResultsThe median follow-up was 139 months. For the entire cohort, 10-year overall survival (OS) and progression free survival (PFS) were 89.5% and 78.7% respectively. The overall eye preservation rate (EPR) was 81.25% (6/32 eyes). Ten-year local control (LC) was 80.95%. Of the 42 eyes, 1 was Group III (Reese-Ellsworth), 3 were Group IV, and 38 were Group V. Twenty-eight eyes (67%) were treated with a relative lens sparing (RLS) technique. Ten eyes (24%) were treated with a modified lens sparing (MLS) technique. Four eyes were treated with other techniques: Electron beam = 1, I-125 eyeplaque = 1, and mixed beam = 2. Thirteen (31%) eyes received <45 Gy, and 29 (69%) received ≥45 Gy. Seventeen (55%) patients received chemotherapy. No difference in toxicity was found for either dose (OR = 0.76, 95% CI, 0.17-3.42, p = 0.72) or technique, comparing MLS vs RLS (OR = 1.87, 95% CI, 0.36-9.63, p = 0.46). No difference in EPR was found for either dose (OR = 2.25, 95% CI, 0.37-13.67, p = 0.38) or technique, comparing MLS vs RLS (OR = 2.57; 95% CI, 0.25-26.85, p = 0.43). Additionally, there was no difference in LC, PFS, or OS by radiation dose group. There was one radiation induced malignancy. The median follow-up was 139 months. For the entire cohort, 10-year overall survival (OS) and progression free survival (PFS) were 89.5% and 78.7% respectively. The overall eye preservation rate (EPR) was 81.25% (6/32 eyes). Ten-year local control (LC) was 80.95%. Of the 42 eyes, 1 was Group III (Reese-Ellsworth), 3 were Group IV, and 38 were Group V. Twenty-eight eyes (67%) were treated with a relative lens sparing (RLS) technique. Ten eyes (24%) were treated with a modified lens sparing (MLS) technique. Four eyes were treated with other techniques: Electron beam = 1, I-125 eyeplaque = 1, and mixed beam = 2. Thirteen (31%) eyes received <45 Gy, and 29 (69%) received ≥45 Gy. Seventeen (55%) patients received chemotherapy. No difference in toxicity was found for either dose (OR = 0.76, 95% CI, 0.17-3.42, p = 0.72) or technique, comparing MLS vs RLS (OR = 1.87, 95% CI, 0.36-9.63, p = 0.46). No difference in EPR was found for either dose (OR = 2.25, 95% CI, 0.37-13.67, p = 0.38) or technique, comparing MLS vs RLS (OR = 2.57; 95% CI, 0.25-26.85, p = 0.43). Additionally, there was no difference in LC, PFS, or OS by radiation dose group. There was one radiation induced malignancy. ConclusionsPoster Viewing Abstract 3035; TableOutcomePrognostic factorsCategoryHR (95% CI)P valueLRRDose ≥4500Yes vs no1.80 (0.20, 16.11).599PFSDose ≥4500Yes vs no1.99 (0.24, 16.53).525OSDose ≥4500Yes vs no0.66 (0.11, 3.95).649 Open table in a new tab