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Retinoblastoma is the most common [[malignant]] intraocular [[tumor]] in children. Retinoblastoma may be classified into several subgroups based on the International Retinoblastoma Staging System (IRSS). On gross pathology, viable tumor [[cells]] near [[blood vessels]] and zones of necrosis in avascular areas are characteristic findings of retinoblastoma. On [[microscopic]] [[histopathological]] analysis, a small round-cell tumor of neuroepithelial origin, Flexner-Wintersteiner rosettes, and Homer-Wright rosettes are characteristic findings of retinoblastoma. Retinoblastoma can be bilateral or unilateral, spontaneous or [[familial]]. In 30% to 40% of cases, retinoblastoma is accompanied by a germinal mutation in the ''RB1'' [[gene]]. The incidence of retinoblastoma in the United States is approximately 0.43 cases per 100,000 children under 15 years of age. The median age at diagnosis of retinoblastoma is 18 months. The average age at diagnosis of retinoblastoma for children with bilateral and unilateral disease is 12 months and 24 months respectively. Retinoblastoma affects males and females equally. There is no racial predilection to the development of retinoblastoma. Common risk factors in the development of retinoblastoma are advanced paternal age, positive [[family history]], and [[viral]] exposure. The hallmark of retinoblastoma is [[leukocoria]] which is an abnormal appearance of the [[retina]] as viewed through the [[pupil]], also known as amaurotic cat's eye reflex. A positive family history of retinoblastoma may be present. Less common symptoms of retinoblastoma include deterioration of vision, a red and irritated eye, eye [[pain]], [[proptosis]], and [[fever]]. Common physical examination findings of retinoblastoma include [[leukocoria]], [[strabismus]], [[proptosis]], [[anisocoria]], [[orbital cellulitis]], [[hyphema]], [[heterochromia iridis]], poor vision, unilateral [[mydriasis]], [[rubeosis iridis]], vitreous [[hemorrhage]], and findings of chalky white-gray retinal mass on fundoscopic examination. The optimal therapy for retinoblastoma depends on several factors such as tumor size, [[tumor]] location, presence or absence of [[vitreous]] or subretinal seeds, and patient age. The various treatment modalities for retinoblastoma include, [[enucleation]], external beam [[radiation therapy]], radioactive plaques (I-125 [[brachytherapy]]), [[cryotherapy]], [[laser photocoagulation]], [[thermotherapy]], and [[chemotherapy]] (which includes systemic, intra-arterial, and [[intravitreal]]). When the retinoblastoma is too large to be treated by other treatment modalities, surgery may be used. In these situations, [[enucleation]] may help to prevent [[metastasis]]. | Retinoblastoma is the most common [[malignant]] intraocular [[tumor]] in children. Retinoblastoma may be classified into several subgroups based on the International Retinoblastoma Staging System (IRSS). On gross pathology, viable tumor [[cells]] near [[blood vessels]] and zones of necrosis in avascular areas are characteristic findings of retinoblastoma. On [[microscopic]] [[histopathological]] analysis, a small round-cell tumor of neuroepithelial origin, Flexner-Wintersteiner rosettes, and Homer-Wright rosettes are characteristic findings of retinoblastoma. Retinoblastoma can be bilateral or unilateral, spontaneous or [[familial]]. In 30% to 40% of cases, retinoblastoma is accompanied by a germinal mutation in the ''RB1'' [[gene]]. The incidence of retinoblastoma in the United States is approximately 0.43 cases per 100,000 children under 15 years of age. The median age at diagnosis of retinoblastoma is 18 months. The average age at diagnosis of retinoblastoma for children with bilateral and unilateral disease is 12 months and 24 months respectively. Retinoblastoma affects males and females equally. There is no racial predilection to the development of retinoblastoma. Common risk factors in the development of retinoblastoma are advanced paternal age, positive [[family history]], and [[viral]] exposure. The hallmark of retinoblastoma is [[leukocoria]] which is an abnormal appearance of the [[retina]] as viewed through the [[pupil]], also known as amaurotic cat's eye reflex. A positive family history of retinoblastoma may be present. Less common symptoms of retinoblastoma include deterioration of vision, a red and irritated eye, eye [[pain]], [[proptosis]], and [[fever]]. Common physical examination findings of retinoblastoma include [[leukocoria]], [[strabismus]], [[proptosis]], [[anisocoria]], [[orbital cellulitis]], [[hyphema]], [[heterochromia iridis]], poor vision, unilateral [[mydriasis]], [[rubeosis iridis]], vitreous [[hemorrhage]], and findings of chalky white-gray retinal mass on fundoscopic examination. The optimal therapy for retinoblastoma depends on several factors such as tumor size, [[tumor]] location, presence or absence of [[vitreous]] or subretinal seeds, and patient age. The various treatment modalities for retinoblastoma include, [[enucleation]], external beam [[radiation therapy]], radioactive plaques (I-125 [[brachytherapy]]), [[cryotherapy]], [[laser photocoagulation]], [[thermotherapy]], and [[chemotherapy]] (which includes systemic, intra-arterial, and [[intravitreal]]). When the retinoblastoma is too large to be treated by other treatment modalities, surgery may be used. In these situations, [[enucleation]] may help to prevent [[metastasis]]. | ||
==Historic Perspective== | ==Historic Perspective== | ||
Retinoblastoma was first described in 1809 by James Wardrop. | [[Retinoblastoma]] was first described in 1809 by Dr. James Wardrop. Then, Dr. Flexner, in 1891, was the first to discover the rosette structure within the [[tumor]].In 1953, Dr. Kupfer was the first [[ophthalmologist]] who tried a combination of [[chemotherapy]] and [[radiotherapy]] for the treatment of the [[tumor]]. | ||
==Classification== | ==Classification== | ||
Retinoblastoma may be classified into several subgroups based on the International Retinoblastoma Staging System (IRSS). | Retinoblastoma may be classified into several subgroups based on the International Retinoblastoma Staging System (IRSS). |
Revision as of 12:57, 16 May 2019
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1],Associate Editor(s)-in-Chief: Simrat Sarai, M.D. [2]
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Overview
Retinoblastoma is the most common malignant intraocular tumor in children. Retinoblastoma may be classified into several subgroups based on the International Retinoblastoma Staging System (IRSS). On gross pathology, viable tumor cells near blood vessels and zones of necrosis in avascular areas are characteristic findings of retinoblastoma. On microscopic histopathological analysis, a small round-cell tumor of neuroepithelial origin, Flexner-Wintersteiner rosettes, and Homer-Wright rosettes are characteristic findings of retinoblastoma. Retinoblastoma can be bilateral or unilateral, spontaneous or familial. In 30% to 40% of cases, retinoblastoma is accompanied by a germinal mutation in the RB1 gene. The incidence of retinoblastoma in the United States is approximately 0.43 cases per 100,000 children under 15 years of age. The median age at diagnosis of retinoblastoma is 18 months. The average age at diagnosis of retinoblastoma for children with bilateral and unilateral disease is 12 months and 24 months respectively. Retinoblastoma affects males and females equally. There is no racial predilection to the development of retinoblastoma. Common risk factors in the development of retinoblastoma are advanced paternal age, positive family history, and viral exposure. The hallmark of retinoblastoma is leukocoria which is an abnormal appearance of the retina as viewed through the pupil, also known as amaurotic cat's eye reflex. A positive family history of retinoblastoma may be present. Less common symptoms of retinoblastoma include deterioration of vision, a red and irritated eye, eye pain, proptosis, and fever. Common physical examination findings of retinoblastoma include leukocoria, strabismus, proptosis, anisocoria, orbital cellulitis, hyphema, heterochromia iridis, poor vision, unilateral mydriasis, rubeosis iridis, vitreous hemorrhage, and findings of chalky white-gray retinal mass on fundoscopic examination. The optimal therapy for retinoblastoma depends on several factors such as tumor size, tumor location, presence or absence of vitreous or subretinal seeds, and patient age. The various treatment modalities for retinoblastoma include, enucleation, external beam radiation therapy, radioactive plaques (I-125 brachytherapy), cryotherapy, laser photocoagulation, thermotherapy, and chemotherapy (which includes systemic, intra-arterial, and intravitreal). When the retinoblastoma is too large to be treated by other treatment modalities, surgery may be used. In these situations, enucleation may help to prevent metastasis.
Historic Perspective
Retinoblastoma was first described in 1809 by Dr. James Wardrop. Then, Dr. Flexner, in 1891, was the first to discover the rosette structure within the tumor.In 1953, Dr. Kupfer was the first ophthalmologist who tried a combination of chemotherapy and radiotherapy for the treatment of the tumor.
Classification
Retinoblastoma may be classified into several subgroups based on the International Retinoblastoma Staging System (IRSS).
Pathophysiology
On gross pathology, viable tumor cells near blood vessels and zones of necrosis in avascular areas are characteristic findings of retinoblastoma. On microscopic histopathological analysis, a small round-cell tumor of neuroepithelial origin, Flexner-Wintersteiner rosettes, and Homer-Wright rosettes are characteristic findings of retinoblastoma. Retinoblastoma can be bilateral or unilateral, spontaneous or familial. In 30% to 40% of cases retinoblastoma is accompanied by a germinal mutation in the RB1 gene.
Causes
Retinoblastoma is caused by a mutation in the RB1 gene.
Differential Diagnosis
Retinoblastoma must be differentiated from other diseases that cause leukocoria such as congenital cataract, persistent fetal vasculature, Coats disease, coloboma of choroid or optic disc, toxocariasis, astrocytic hamartoma, retinopathy of prematurity, vitreous hemorrhage, uveitis, retinal dysplasia, and medulloepithelioma.
Epidemiology and Demographics
The incidence of retinoblastoma in the United States is approximately .43 cases per 1000,000 children under 15 years of age. The median age at diagnosis of retinoblastoma is 18 months. The average age at diagnosis of retinoblastoma for children with unilateral disease and bilateral disease is 24 months and 12 months respectively. Retinoblastoma affects males and females equally. There is no racial predilection to the development of retinoblastoma.
Risk factors
Common risk factors in the development of retinoblastoma are advanced paternal age, positive family history, and viral exposure.
Screening
According to the United States Preventive Services Task Force, screening for retinoblastoma is not recommended in the general population. However, children with an increased risk of retinoblastoma such as those with a known 13q deletion or family history should be evaluated by an ophthalmologist shortly after birth. Dilated fundus examinations are recommended in siblings and offspring of patients with retinoblastoma.
Natural history,Complications and Prognosis
If left untreated, retinoblastoma may progress to develop seeding in the eye, leading to retinal detachment, necrosis and invasion of the orbit, optic nerve invasion, and central nervous system invasion. The majority of untreated patients die of intracranial extension and disseminated disease within one year. Spontaneous regression of the tumor is a rare occurrence but may occur in a small number of cases. Common complications of retinoblastoma include metastasis, tumor recurrence, trilateral retinoblastoma, and subsequent neoplasms. Prognosis is generally good, and the survival rate of patients with retinoblastoma with treatment is approximately 95% in the United States.
History and Symptoms
The hallmark of retinoblastoma is leukocoria which is an abnormal appearance of the retina as viewed through the pupil, also known as amaurotic cat's eye reflex. A positive family history of retinoblastoma may be present. Less common symptoms of retinoblastoma include deterioration of vision, a red and irritated eye, eye pain, proptosis, and fever.
Physical Examination
Common physical examination findings of retinoblastoma include leukocoria, strabismus, proptosis, anisocoria, orbital cellulitis, hyphema, heterochromia iridis, poor vision, unilateral mydriasis, rubeosis iridis, vitreous hemorrhage, and findings of chalky white-gray retinal mass on fundoscopic examination.
Laboratory Tests
There are no diagnostic lab findings associated with retinoblastoma.
Chest X Ray
There are no chest x-ray findings associated with retinoblastoma.
CT scan
Head and neck CT scan may be diagnostic of retinoblastoma. Findings on CT scan suggestive of retinoblastoma include retrolental mass that is usually calcified and a dense vitreous due to hemorrhage.
MRI scan
On head and neck MRI, retinoblastoma is characterized by isointense to hypointense mass on T1-weighted MRI and hyperintense mass on T2-weighted MRI.
Ultrasound
On ultrasound, retinoblastoma is characterized by echogenic soft-tissue masses with variable shadowing due to calcifications and heterogeneity due to necrosis and/or hemorrhage.
Other Imaging Studies
Other imaging studies for retinoblastoma include wide-field fundus photography and spectral domain optical coherence tomography.
Other Diagnostic Studies
Other diagnostic studies for retinoblastoma include fluorescein angiography, bone marrow aspiration, lumbar puncture, bone scan, and genetic testing.
Medical therapy
The optimal therapy for retinoblastoma depends on several factors such as tumor size, tumor location, presence or absence of vitreous or subretinal seeds, and patient age. The various treatment modalities for retinoblastoma include enucleation, external beam radiation therapy, radioactive plaques (I-125 brachytherapy), cryotherapy, laser photocoagulation, thermotherapy, and chemotherapy (which includes systemic, intra-arterial, and intravitreal).
Surgical therapy
The feasibility of surgery depends on the tumor size, tumor location, and presence or absence of vitreous or subretinal seeds at diagnosis. When the retinoblastoma is too large to be treated by other treatment modalities, surgery may be used. In these situations, enucleation may help to prevent metastasis.
Primary Prevention
There are no primary preventive measures available for retinoblastoma.
Secondary Prevention
Secondary prevention strategies following retinoblastoma include cessation of smoking, reduction in sun exposure, and reduction in exposure to ionizing radiation.
References