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Retinoblastoma
Retinoblastoma
Mario Cotton
Kristin Gartman
Kristen Ryan
Stephen F. Austin State University
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Retinoblastoma
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RETINOBLASTOMA
What Is Retinoblastoma?
Retinoblastoma (reh-tin-oh-blast-oma) is a childhood cancer arising from
immature retinal cells in one or both eyes and can strike from the time a child is in the
womb up to 5 years of age. This cancer is curable if caught early enough. However,
87% of the children stricken with this disease worldwide die, mostly in developing
countries. In developed countries, 97% of those who do live have moderate to severe
visual impairment.
Retinoblastoma is a relatively uncommon tumor of childhood that accounts for
about 3% of the cancers in children under the age of 15. The tumors originate in the
retina, the light sensitive layer of the eye, which enables the eye to see. When the
tumors are present in one eye, it is referred to as unilateral retinoblastoma, and when it
occurs in both eyes it is referred to as bilateral retinoblastoma. 60% of the cases involve
only one eye (unilateral); the rest affect both eyes (bilateral). 90% of retinoblastoma
patients have no family history of the disease and only 10% of newly diagnosed patients
have other family members with retinoblastoma.
Early diagnosis and intervention is critical to the successful treatment of this disease.
Common signs of retinoblastoma include:
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a white "glow" or "glint" in the pupil of one or both eyes in dim lighting
white pupil in a color photo
crossed or misaligned eyes
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If you notice a white glow in any of your children’s photos, please contact your
pediatrician or ophthalmologist immediately and have their eyes examined. Request
pupil dilation of both eyes. If your physician is unable or unwilling to do the pupil
dilation, please insist on a referral.
Although it is rare, retinoblastoma can spread or metastasize outside of the eye
to the brain, the central nervous system (brain and spinal cord), and the bones. In these
cases, chemotherapy is prescribed by a pediatric oncologist and is administered through
the peripheral blood vessels or into the brain for months to years after initial diagnosis
of metastatic disease.
Symptoms
The white reflection often picked up in photographs is called leukokoria; when a
tumor is present in the eye it prevents the lights of a camera's flash from reaching the
back of the eye for processing by the retina. The flash can create a white eye effect due
to the tumour or tumors instead of the familiar red eye effect that we often see in a
healthy eye. Leukocoria (white pupil) and misaligned eyes (strabismus) are the most
common signs of retinoblastoma. In other cases, the child may have developed
neovascular glaucoma and may be in pain. Longstanding glaucoma can cause
enlargement of the eye (buphthalmos). Children with neovascular glaucoma and
enlargement of the eye are at greater risk for extraocular spread of their retinoblastoma.
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A family history of retinoblastoma can be very important. Retinoblastoma was
the first cancer to be directly associated with a genetic abnormality (Deletions or
mutation of the q14 band of chromosome 13). Retinoblastoma can occur sporadically
(without a family history) or it can be inherited (with
a family history).
If a genetic mutation is found there is a 45-50% chance that the parents will have
another child with retinoblastoma. If there is no family history and no mutation is
found, the risk of having a second child with retinoblastoma is 2-5%. The average age of
children first diagnosed with retinoblastoma is 18 months.
Treatment of Retinoblastoma
The treatment of retinoblastoma is customized for each patient. Almost all
parents choose some form of treatment for their child. No treatment may mean that the
child would die. Goals of treatment from most to least important ranking are: saving
life, maintaining the eye and vision, and preserving cosmetic appearance.
Enucleation (ee-nuke-lee-a-shon) is the most common form of treatment for
retinoblastoma. During an enucleation, the eye is surgically removed. This is necessary
because it is the only way to remove the cancer completely.
The removal of the eye is done under general anesthesia (the child is asleep). A
parent may accompany the child to the operating room on the day of surgery and may
be present until the child is anesthetized.
The eyebrow, lids, and muscles of the eye are all left in place. Blinking, tearing,
and movement of the brow are not affected from this surgery. The operation takes less
than an hour and is not painful. Children go home the same day and are usually
examined in the office on the following day when post-operative instructions and care
are explained.
A ball of plastic, rubber, or coral is placed where the eye had been so there is no
cavity or hole. When both eyes are involved, sometimes the more involved or "worse"
eye is enucleated, while the other eye may be treated with one of the vision-preserving
treatments, such as external-beam radiation, plaque therapy, cryotherapy, laser
treatment, and chemoreduction which are described below.
External beam radiation has been used since the early 1900's as a way to save the
eye(s) and vision. The radiation treatment is performed on an outpatient basis five times
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per week over a 3 to 4 week stretch. Immediately after treatment, the skin may be
sunburned or a small patch of hair may be lost in the back of the head from the beam
exit position. Following external beam radiation, long-term effects can include cataracts,
radiation retinopathy (bleeding and exudates of the retina), impaired vision, and
temporal bone suppression (bones on the side of the head which do not grow
normally).
Radioactive plaques are disks of radioactive material that were developed in the
1930's to radiate retinoblastoma. The child must be hospitalized for this procedure, and
undergoes two separate operations (one to insert the plaque and one to remove it) over
3 to 7 days. No pregnant visitors or health care professionals may visit or care for the
child, and children under twelve years old are not permitted to visit. Following the
plaque, long-term effects including cataracts, radiation retinopathy, and impaired
vision may occur.
Laser therapy, sometimes called photocoagulation or laser hyperthermia (which
are two different techniques), is a non-invasive treatment for retinoblastoma. Lasers vey
effectively destroy smaller retinoblastoma tumors. This type of treatment is usually
done by focusing light through the pupil onto and surrounding the cancers in the eye.
Laser treatment is done under local or general anesthesia, usually does not have any
post-operative pain associated with it, and does not require any post-operative
medications.
Cryotherapy is another treatment which is performed under local or general
anesthesia and freezes smaller retinoblastoma tumors. Cryotherapy usually has to be
repeated many times to successfully destroy all of the cancer cells. Cryotherapy causes
the lids and eye to swell for 1 to 5 days; sometimes the swelling is so much that the
children are unable to open their lids for a few days. Eye drops or ointment can be
given to reduce the swelling.
Chemoreduction is the treatment of retinoblastoma with chemotherapy.
Chemotherapy is given intravenously to your child, passes through the blood stream,
and causes the tumors to shrink within a few weeks if successful. Children may require
as many as twenty treatments with re-examinations of the eye under anesthesia every 3
weeks.
Frequency
United States
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It is estimated that around 250-500 new cases of retinoblastoma occur in the
United States yearly.
International
Worldwide, the incidence of retinoblastoma is recorded to be about 11 cases per
million children younger than 5 years. A more commonly used estimate is 1 case of
retinoblastoma per 18,000-30,000 live births, depending on the country.
In the Philippines, unpublished reports have estimated the incidence to be
greater than 1 case of retinoblastoma per 18,000 live births.
Mortality/Morbidity
Survival rates for patients with retinoblastoma range from a reported 86-92%.
However, this must be kept in the context of the retinoblastoma cancers. In actuality,
the survival rate drops with each decade of life for patients with the genomic mutation.
The genomic mutation is a gene mutation within every cell of the individual's body.
These patients typically present with either bilateral disease or unilateral-multifocal
(one eye with multiple distinctly separate tumor foci) disease. These individuals have a
predisposition for developing second cancers later in life.
Mortality in these individuals is consequently much higher than those with
somatic mutations (ie, affecting one retinal cell only and unilateral-unifocal disease).
The greatest predictor of death is extraocular extension, either directly through the
sclera or via extension along the optic nerve. Several of these topics are discussed
further in later sections of this article.
Race
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There seems to be no racial predilection for retinoblastoma.
No difference in incidence exists among blacks and whites.
Sex
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Age
Studies show that there appears to be no significant difference in the incidence of
retinoblastoma by sex for children aged 0-14 years.
The estimated boys-to-girls ratio is reportedly 1.12:1.
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Retinoblastoma is diagnosed at an average of 18 months with 90% diagnosed before
patients reach age 5 years.
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Children who are affected bilaterally are diagnosed at an average age of 13
months, while patients with unilateral retinoblastoma are diagnosed at an
average age of 24 months.
When a known family history of retinoblastoma exists, patients with bilateral
retinoblastoma are diagnosed at an average age of 11 months.
A few cases of retinoblastoma in adults (aged 20 y and older) have been reported
in the literature. Some theorize that these lesions arise from a previously existing
retinocytoma that underwent malignant transformation.
Good info for Parents
Side Effects of Cancer and Cancer Treatment
Cancer and cancer treatment can cause a variety of side effects; some are easily
controlled and others require specialized care. Below are some of the side effects that
are more common to retinoblastoma and its treatments.
Fatigue. Fatigue is extreme exhaustion or tiredness, and is the most common
problem that people with cancer experience. More than half of patients experience
fatigue during chemotherapy or radiation therapy, and up to 70% of patients with
advanced cancer experience fatigue. Patients who feel fatigue often say that even a
small effort, such as walking across a room, can seem like too much. Fatigue can
seriously impact family and other daily activities, can make patients avoid or skip
cancer treatments, and may even impact the will to live.
Nausea and vomiting. Vomiting, also called emesis or throwing up, is the act of
expelling the contents of the stomach through the mouth. It is a natural way for the
body to rid itself of harmful substances. Nausea is the urge to vomit. Nausea and
vomiting are common in patients receiving chemotherapy for cancer and in some
patients receiving radiation therapy. Many patients with cancer say they fear nausea
and vomiting more than any other side effects of treatment. When it is minor and
treated quickly, nausea and vomiting can be quite uncomfortable but cause no serious
problems. Persistent vomiting can cause dehydration, electrolyte imbalance, weight
loss, depression, and avoidance of chemotherapy.
After Treatment
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All children cured of cancer, including those with retinoblastoma, require lifelong, follow-up care. Once a child has been free of retinoblastoma for two to four years
following treatment, and is considered cured, the emphasis during periodic follow-up
visits changes. Pediatric oncologists will focus on the quality of the child's life,
including developmental and emotional concerns.
Most young children adapt well to the loss of one eye if enucleation took place.
Rarely, both eyes will require removal to save the child's life. If both eyes are removed,
the local educational system is required to provide special services. Parents are
encouraged to investigate the school's services and advocate on their child's behalf.
Based on the therapy the child received and whether the child has the genetic
form of retinoblastoma, the doctor will determine what evaluations are needed to check
for long-term effects. This may include imaging studies (CT scan or MRI) and blood
tests. Counseling will also be provided in the case of children who have an increased
risk of additional tumors later in life, such as those with retinoblastoma in both eyes
and those with one eye affected and who have a family history of the disease. Annual
visits to specialized ophthalmologic and medical oncologists are necessary in order to
fully monitor the child's recovery and to increase the probability that a second cancer
will be detected in its earliest stages.
Children who have had cancer can also enhance the quality of their future by
following established guidelines for good health into and through adulthood, including
not smoking, maintaining a healthy weight, and avoiding drinking alcohol in excess.
Questions to Ask the Doctor
Regular communication with your child's doctor is important in making
informed decisions about his or her health care. Consider asking the following
questions of your child's doctor:
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Does my child have the genetic form of retinoblastoma?
What is the stage of the disease?
What are the treatment options?
What clinical trials are open for my child?
What treatment do you recommend? Why?
What is the likelihood that the recommended treatment can save my child's
vision?
What can I expect chemotherapy to accomplish in the treatment of my child's
cancer?
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What are the relative benefits and risks of radiation treatment in treating my
child?
What are the common side effects of each treatment, in the short term and long
term?
What follow-up tests will my child need, and when will they be needed?
Retinoblastoma Tidbits
Cancer Facts:
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Cancerous growths have been discovered in dinosaurs!
Retinoblastoma was documented in children more than 2,000 years ago
Retinoblastoma Facts:
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More than 95% of patients treated for retinoblastoma in the U.S. are cured
More than 90% of patients retain at least one eye
More than 80% of the children keep 20/20 vision
Complete blindness is unusual in children who have been successfully treated
for retinoblastoma
Did you Know?
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Retinoblastoma is a cancer
Retinoblastoma is the most common eye cancer in children
Retinoblastoma is about as common as hemophilia
Retinoblastoma affects boys as commonly as girls
The average age for diagnosis of retinoblastoma when one eye is involved is 2.5
years
There are 350 new cases of retinoblastoma per year in the U.S. and about 5,000
worldwide
Retinoblastoma affects all races equally
Diagnostic Facts:
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Retinoblastoma is diagnosed with the indirect ophthalmoscope, ultrasound,
CT/MRI scans
Biopsies are rarely necessary
Anesthesia for examination and treatment may be necessary as often as every 2
weeks
Examination of the parents may help in the diagnosis of the child
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Retinoblastoma
Patient Information Resources
Candlelighters Childhood Cancer Foundation
P.O. Box 498
Kensington, MD 20895
Toll Free: 800-366-2223
Phone: 301-962-3520
www.candlelighters.org
Children's Hospice International
901 N. Pitt St., Ste. 230
Alexandria, VA 22314
Toll Free: 800-24-CHILD (800-242-4453)
Phone: 703-684-0330
www.chionline.org
The Eye Cancer Network
Eye Care Foundation
115 E. 61st Street
New York, NY 10021
Phone: 212-832-8170
www.eyecancer.com
Make-A-Wish Foundation
3550 N Central Ave., Ste. 300
Phoenix, AZ 85012
Toll Free: 800-722-9474
www.wish.org
National Childhood Cancer Foundation
440 E Huntington Dr.
P.O. Box 60012
Arcadia, CA 91006-6012
Toll Free: 800-458-6223 (US and Canada only)
Phone: 626-447-1674
www.nccf.org
www.CureSearch.org
National Children's Cancer Society
1015 Locust, Ste. 600
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Retinoblastoma
St. Louis, MO 63101
Toll Free: 800-532-6459
www.nationalchildrenscancersociety.org
Outlook: Life Beyond Childhood Cancer
www.outlook-life.org
The Children's Cause for Cancer Advocacy
1010 Wayne Ave., Ste. 770
Silver Spring, MD 20910
Phone: 301-562-2765
www.childrenscause.org
The Starlight Starbright Foundation
1850 Sawtelle Blvd., Ste. 450
Los Angeles, CA 90064
Phone: 310-479-1212
www.slsb.org
National Organization for Rare Disorders (NORD)
55 Kenosia Ave.
P.O. Box 1968
Danbury, CT 06813-1968
Phone: 203-744-0100
www.rarediseases.org
Rare Cancer Alliance
1649 N. Pacana Way
Green Valley, AZ 85614
Phone: 206-600-5327 www.rare-cancer.org
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References
About Retinoblastoma. (n.d.). Retrieved July 30, 2008, from
www.chect.org.uk
Abramson, David H., MD, FACS & Servodidio, Camille, RN, MPH. (1997-2002). A
Parent’s Guide to Understanding Retinoblastoma. Retrieved July 30, 2008, from
www.retinoblastoma.com
Adventura, Marichelle L., MD, Roque, Manolette R., MD, MBA, DPBO, FPAO, Aaberg,
Thomas M., Jr, MD & Roque, Barbara, L., MD. (2006, February 16).
Retinoblastoma. Retrieved July 30, 2008, from
www.emedicine.com/oph/topic346.htm
Finger, Paul T., MD. (1998-2008). Retinoblastoma. Retrieved July 30, 2008, from
http://www.eyecancer.com/Patient/Condition.aspx?nID=53&Category=Retinal+T
umors&Condition=Retinoblastoma
Retinoblastoma – Childhood. (2006-2008). Retrieved July 30, 2008, from
http://www.cancer.net/patient/Cancer+Types/Retinoblastoma+-+Childhood
What is retinoblastoma? (n.d.). Retrieved July 30, 2008, from
http://www.retinoblastoma.net/whatisrb.html