Other Late Effects

Diminished orbital growth. Orbital growth is somewhat diminished after enucleation. However, the impact of enucleation on orbital volume may be minimized after placement of an orbital implant.[31] Asymmetry of orbital size that develops after enucleation is greater in younger children and infants, but enucleation after age 3 years does not result in orbital asymmetry.[32]

Visual-field deficits. Patients with retinoblastoma demonstrate a variety of long-term visual-field defects after treatment for their intraocular disease. These defects are related to tumor size, location, and treatment method.[33] One study of visual acuity after treatment with systemic chemotherapy and local ophthalmic therapy was conducted in 54 eyes of 40 children. After a mean follow-up of 68 months, 27 eyes (50%) had a final visual acuity of 20/40 or better, and 36 eyes (67%) had a final visual acuity of 20/200 or better. The clinical factors that predicted visual acuity of 20/40 or better were a tumor margin of at least 3 mm from the foveola and optic disc and an absence of subretinal fluid.[34]

Strabismus. In a study of 42 survivors of retinoblastoma (64 eyes) who underwent successful conservative treatment, 69% of patients were noted to have strabismus at final follow-up (mean, 93.7 months). Exotropia was the most common type of strabismus reported. Conservative treatments included intravenous chemotherapy (62 eyes), intra-arterial chemotherapy (10 eyes), brachytherapy (11 eyes), transpupillary thermotherapy (22 eyes), cryotherapy (47 eyes), and external-beam radiation therapy (4 eyes). On multivariate analysis, only foveal involvement was found to be a significant risk factor for developing strabismus (P < .001).[35]

Hearing loss. Because systemic carboplatin is now commonly used in the treatment of retinoblastoma, concern has been raised about hearing loss related to therapy. For more information about treatment, see the sections on Treatment of Intraocular Retinoblastoma and Treatment of Extraocular Retinoblastoma. While two large studies that included children treated with six cycles of carboplatin-containing therapy (18.6 mg/kg per cycle) showed an incidence of treatment-related hearing loss of lower than 1%,[36,37] a separate series documented some degree of hearing loss in 17% of patients.[38] In the latter study, younger age (younger than 6 months at the time of treatment) and higher carboplatin systemic exposures correlated with an increased risk of ototoxicity.[38,39]

Neurocognitive functioning. Early studies of intellectual functioning in survivors of retinoblastoma suggested above average intelligence among survivors of bilateral disease compared with unaffected siblings and the general population, especially in those who were blind as a result of their disease.[40-42] Later studies have yielded mixed results with conflicting findings, in part, resulting from the low test-retest reliability of measures used to assess cognitive outcomes at a very young age, as well as temporal differences in treatment exposures.

Neurocognitive functioning. Early studies of intellectual functioning in survivors of retinoblastoma suggested above average intelligence among survivors of bilateral disease compared with unaffected siblings and the general population, especially in those who were blind as a result of their disease.[40-42] Later studies have yielded mixed results with conflicting findings, in part, resulting from the low test-retest reliability of measures used to assess cognitive outcomes at a very young age, as well as temporal differences in treatment exposures.

Serial assessment of cognitive and adaptive functioning in a group of survivors younger than 6 years revealed declines in developmental functioning over time, with the most pronounced declines observed in patients with 13q deletions.[43]

Neurocognitive functioning. Early studies of intellectual functioning in survivors of retinoblastoma suggested above average intelligence among survivors of bilateral disease compared with unaffected siblings and the general population, especially in those who were blind as a result of their disease.[40-42] Later studies have yielded mixed results with conflicting findings, in part, resulting from the low test-retest reliability of measures used to assess cognitive outcomes at a very young age, as well as temporal differences in treatment exposures. › Serial assessment of cognitive and adaptive functioning in a group of survivors younger than 6 years revealed declines in developmental functioning over time, with the most pronounced declines observed in patients with 13q deletions.[43]

Further longitudinal follow-up of this cohort identified improvement in adaptive functioning in all treatment groups and improvement in cognitive functioning in survivors who were treated with enucleation alone between the ages of 5 years and 10 years.[44]

Neurocognitive functioning. Early studies of intellectual functioning in survivors of retinoblastoma suggested above average intelligence among survivors of bilateral disease compared with unaffected siblings and the general population, especially in those who were blind as a result of their disease.[40-42] Later studies have yielded mixed results with conflicting findings, in part, resulting from the low test-retest reliability of measures used to assess cognitive outcomes at a very young age, as well as temporal differences in treatment exposures. › Serial assessment of cognitive and adaptive functioning in a group of survivors younger than 6 years revealed declines in developmental functioning over time, with the most pronounced declines observed in patients with 13q deletions.[43]

At age 10 years, overall functioning was generally within the average range, although estimated intelligence quotient was significantly below the normative mean for children who were treated with enucleation alone.[44]

Neurocognitive functioning. Early studies of intellectual functioning in survivors of retinoblastoma suggested above average intelligence among survivors of bilateral disease compared with unaffected siblings and the general population, especially in those who were blind as a result of their disease.[40-42] Later studies have yielded mixed results with conflicting findings, in part, resulting from the low test-retest reliability of measures used to assess cognitive outcomes at a very young age, as well as temporal differences in treatment exposures.

A study of very long-term adult survivors of retinoblastoma, who were on average 33 years postdiagnosis, demonstrated largely average cognitive functioning across domains of intelligence, memory, attention, and executive function.[45]