A familial malignant ocular embryonic tumor develops
in the retina because of a defect in a regulatory gene. Prognosis is good.
Association with other primary malignancies is frequent.
This 2-year-old boy with bilateral retinoblastoma shows typical
leukocoria (white “cat's eye” reflex).
The funduscopy in a preterm baby reveals two
Estimated at 1:16,000 to 23,000 live births in the
United States. Over 90% are diagnosed before the age of 5 years. Nonwhite
individuals present with a prevalence four times greater than whites.
Bilateral cases occur in 20%.
In general, 5 to 10% of cases are
inherited, 20 to 30% are new germinal mutations, and 60 to 70% are
sporadic (unilateral mainly). Most (90%) bilateral cases are familial.
Retinoblastoma gene (Rb) gene is located at 13q14.1-q14.2.
Usually develop in posterior portion of retina
with multiple foci. Typically invade locally and grow forward into vitreous
or backward into optic nerve. Rarely metastasize until very late. Rb gene is
thought to have a suppressor function. Retinoblastoma would occur by loss or
inactivation of both alleles of this gene. There is a high incidence of
second primary tumors, suggesting a key role in the etiology of several
other primary malignancies (osteogenic sarcoma, pinealoma, leukemia, lymphoma,
and Ewing sarcoma).
Clinical features and careful ophthalmologic
examination. CT and MRI assessment of the eye and orbit is also recommended.
Median age at diagnosis is 11 months for bilateral disease and 23 months for
Early presenting feature is leukocoria (white
“cat's eye” reflex), a yellowish-white reflex in the pupil caused by tumor
behind the lens. Other common findings include diminishing or absent vision
and strabismus. In more advanced disease, there may be pupillary
irregularity, hyphema, and pain. Severe disease may have ptosis, raised
intracranial pressure, and bone metastasis. Treatment includes cryotherapy,
laser ablation, local radiation, and, finally, enucleation. Overall survival
is greater than 90%. There is a high risk of other malignancies,
particularly osteogenic sarcoma and other germ cell tumors. Retinoblastoma
may occur in association with other “13q-syndromes,” which are typically
characterized by growth delay, mental retardation, and minor facial
These patients often come to the
operating room for examination, laser therapy, cryotherapy,
radiotherapy, or staging. A review of the chemotherapy and steroid administration must be
obtained. Overall, medical condition must be reviewed.
There are no specific considerations in
isolated form. With multiple and frequent general anesthesia, good rapport
with patient and family is important. If laser ablation is used,
considerations include laser safety and immobility during laser use. All
anesthesia considerations associated to radiotherapy treatment must be