Ch. 502 - Retinoblastoma & Ch. 505.1 - Hemangiomas Flashcards
The most common benign tumors of infancy
Hemangiomas
Hmeangiomas occur in approx ___% of term infants
5-10
Risk of hemangioma is 3-5x higher in boys vs girls
Girls
The risk for hemangiomas is doubled in term vs preterm
Preterm
Risk for hemangioma is higher in offspring of women who had
Chorionic villus sampling
Hemangiomas grow rapidly within ___ year/s
1
Slowing of growth of hemangioma is noted within
Next 5 years after year 1
Involution of hemangioma takes place at ___ y/o
10-15
More than 50% of all hemangiomas are located in the
Head and neck
T/F Most hemangiomas are solitary
T
Presence of more than 1 hemangioma increases the likelihood of
Visceral hemangiomas
Primary site of visceral involvement of hemangiomas
Liver
Other sites of visceral hemangiomas besides the liver
Brain, intestine, lung
Infantile hemangiomas can be diff. from other lesions by the expression of
GLUT1
T/F Most hemangiomas require no therapy
T
Common complication of hemangioma that leads to secondary infection
Ulceration
Large hepatic hemangiomas or hemangioendotheliomas may result in
Hepatomegaly, anemia, thrombocytopenia, and high-output heart failure
Characterized by rapidly enlarging lesion, thrombocytopenia, microangiopathic haemolytic anemia, and coagulopathy as a result of platelet andRBC trapping and activation of the clotting system within the vasculature of the hemangioma
Kasabach-Merritt Syndrome
T/F Kasabach-Merritt syndrome is associated with infantile hemangiomas but not with kaposiform hemangioendotheliomas
F, other way around
T/F Midline hemangioma in the lumbosacral area indicates the need for an MRI to search for underlying asymptomatic neurologic abnormalities
T
MC intraocular tumor in children
Retinoblastoma (Rb)
Rb progresses to metastatic disease and death in ___% of children worldwide
> 50
Rb accounts for ___% of all pediatric malignancies
4
Median age of diagnosis of Rb
2 y/o
More than 90% of Rb cases are diagnosed in children by what age
Younger than 5 y/o
T/F Majority of Rb are unilateral
T, 66-75%
T/F Bilateral Rb is more common in older children
F, younger particularly less than 1 y/o
T/F Bilateral Rb is always heritable
T
T/F There is a possible risk of Rb in children conceived by in vitro fertilization
T
Hereditary vs Sporadic: Diagnosed at a younger age
Hereditary
Hereditary vs Sporadic: Multifocal
Hereditary
Hereditary vs Sporadic: Unilateral
Sporadic
Hereditary vs Sporadic: Unifocal
Sporadic
Hereditary vs Sporadic: Loss of function of RB1 gene
Both
Hereditary vs Sporadic: 2 mutational events
Both
Hereditary vs Sporadic: First mutation through germinal cells then second mutation subsequently in somatic retinal cells
Hereditary
Hereditary vs Sporadic: 2 mutations occur in somatic retinal cells
Sporadic
RB1 gene is located on what chromosome
13q14
RB1 gene encodes for
Retinoblastoma protein, a tumor suppressor protein
Model of oncogenesis in which 2 mutational events are required for tumor development (as in Rb)
Knudson’s “two-hit” model of oncogenesis
T/F All first-degree relatives of children with known or suspected hereditary Rb should have retinal exam
T
Cell formation found histologically in Rb tumors
Flexner-Wintersteiner rosettes
Why Rb tumors have necrotic and calcified areas
Tend to outgrow their blood supply
Endophytic vs exophytic Rb: Arise from the inner surface of the retina
Endophytic
Endophytic vs exophytic Rb: Grow from the outer retinal layer
Exophytic
Endophytic vs exophytic Rb: Can cause retinal detachment
Exophytic
Endophytic vs exophytic Rb: Vitreous seeding
Endophytic
Type of Rb tumor that grows intraretinally and remain flat
Diffuse infiltrating type
Type of Rb tumor that can cause iris neovascularization
Diffuse infiltrating type
T/F Rb tumors can be both endophytic and exophytic
T
Means by which Rb tumors can spread
Direct extension, hematogenous, lymphatic
Route by which Rb can spread to the CNS
Choroid > optic nerve > lamia cribrosa > CNS
Rb classically presents with ___
Leukocoria
Often the initial presenting complaint in patients with Rb
Strabismus
T/F Majority of Rb can be detected by routine ophtha screening in the context of a positive family history
F, only approx 10%
Characteristic ophtha finding in Rb
Chalky, white-gray retinal mass with a soft friable consistency
T/F Imaging studies are diagnostic for Rb
F
T/F Biopsy is done to confirm Rb
F, contraindicated!
Rb disease in which both eyes and the pineal region is involved
Trilateral Rb
Trilateral Rb is seen in ~___% of patients with hereditary Rb
60
T/F Metastatic disease is often present at diagnosis
F, rarely present
Treatment of Rb is determined by
Size and location of tumors
Primary goal of Rb treatment
CURE
Secondary goal of Rb treatment
Preserving vision and the eye itself; decreasing risk of late side effects (mainly secondary malignancies)
Indication for enucleation in Rb
No potential for salvage of useful vision (unresponsive and/or recurrent)
Treatment for bilateral Rb
Chemoreduction + focal therapy (laser photocoagulation or cryotherapy
Treatment for large Rbs
Multiagent therapy, VEC (vinc, etop, carboplatin)
Treatment for large Rb if multi agent chemo fails
External-beam irradiation
T/F In general, Rb has poor prognosis
F, poor only if Rb has spread outside the eye
Routine ophtha exam in children with Rb should continue until
Older than 7 y/o
T/F Trilateral Rb is universally fatal
T
Germline RB1 mutations are at significant risk for development of second malignancies, especially
1) Osteosarcoma 2) Soft tissue sarcomas 3) Malignant melaoma
Factors that increase risk of second malignancy in Rb
1) Germline RB1 mutation 2) Radiation therapy
Adverse of effects of radiation therapy in Rb
1) Second malignancy 2) Cataracts 3) Orbital growth deformities 4) Lacrimal dysfunction 5) Late retinal vascular injury
