Summary

Key Points

• Retinoblastoma is a disease in which malignant (cancer) cells form in the tissues of the retina.
• Retinoblastoma occurs in heritable and nonheritable forms.
• Treatment for both forms of retinoblastoma should include genetic counseling.
• A child who has heritable retinoblastoma has an increased risk of trilateral retinoblastoma and other cancers.
• Signs and symptoms of retinoblastoma include “white pupil” and eye pain or redness.
• Tests that examine the retina are used to detect (find) and diagnose retinoblastoma.
• Certain factors affect prognosis (chance of recovery) and treatment options.

Retinoblastoma is a disease in which malignant (cancer) cells form in the tissues of the retina.

The retina is the nerve tissue that lines the inside of the back of the eye. The retina senses light and sends images to the brain by way of the optic nerve.

Although retinoblastoma may occur at any age, it usually occurs in children younger than 5 years, most often younger than 2 years. The cancer may be in one eye (unilateral) or in both eyes (bilateral). Retinoblastoma rarely spreads from the eye to nearby tissue or other parts of the body.

Risk Factors

Retinoblastoma occurs in heritable and nonheritable forms.

A child is thought to have the heritable form of retinoblastoma when one of the following is true:

• There is a family history of retinoblastoma.
• There is a certain mutation (change) in the RB1 gene. The mutation in the RB1 gene may be passed from the parent to the child or it may occur at the time of conception.
• There is more than one tumor in the eye or there is a tumor in both eyes.
• There is a tumor in one eye and the child is younger than 1 year.

After diagnosis and treatment in a child with heritable retinoblastoma, new tumors may continue to form for a few years. Regular eye exams to check for new tumors are usually done every 2 to 4 months for at least 28 months.

Nonheritable retinoblastoma is retinoblastoma that is not the heritable form. Most cases of retinoblastoma are the nonheritable form.

Treatment for both forms of retinoblastoma should include genetic counseling.

Parents should receive genetic counseling (a discussion with a trained professional about genetic diseases) to discuss whether genetic testing is needed and the risk of retinoblastoma for the child’s brothers or sisters.

A child who has heritable retinoblastoma has an increased risk of trilateral retinoblastoma and other cancers.

A child with heritable retinoblastoma has an increased risk of a pineal tumor in the brain. When retinoblastoma and a brain tumor occur at the same time it is called trilateral retinoblastoma. The brain tumor is usually diagnosed between 20 and 36 months of age. Regular screening using MRI (magnetic resonance imaging) every 6 months for 5 years may be done for a child thought to have heritable retinoblastoma or for a child with retinoblastoma in one eye and a family history of the disease. CT scans (computerized tomography) should not be used for routine screening to avoid exposing the child to ionizing radiation.

Heritable retinoblastoma also increases the child’s risk of other types of cancer such as lung cancer, bladder cancer, or melanoma in later years. Regular follow-up exams are important.

Screening and Detection

Tests that examine the retina are used to detect (find) and diagnose retinoblastoma.

The following tests and procedures may be used:

• Physical exam and history: An exam of the body to check general signs of health, including checking for signs of disease, such as lumps or anything else that seems unusual. A history of the patient’s health habits and past illnesses and treatments will also be taken. The doctor will ask if there is a family history of retinoblastoma.
• Eye exam with dilated pupil: An exam of the eye in which the pupil is dilated (opened wider) with medicated eye drops to allow the doctor to look through the lens and pupil to the retina. The inside of the eye, including the retina and the optic nerve, is examined with a light. Depending on the age of the child, this exam may be done under anesthesia.

There are several types of eye exams that are done with the pupil dilated:

• • Ophthalmoscopy: An exam of the inside of the back of the eye to check the retina and optic nerve using a small magnifying lens and a light.
  • Slit-lamp biomicroscopy: An exam of the inside of the eye to check the retina, optic nerve, and other parts of the eye using a strong beam of light and a microscope.
  • Fluorescein angiography: A procedure to look at blood vessels and the flow of blood inside the eye. An orange fluorescent dye called fluorescein is injected into a blood vessel in the arm and goes into the bloodstream. As the dye travels through blood vessels of the eye, a special camera takes pictures of the retina and choroid to find any blood vessels that are blocked or leaking.
• Ultrasound exam of the eye: A procedure in which high-energy sound waves (ultrasound) are bounced off the internal tissues of the eye to make echoes. Eye drops are used to numb the eye and a small probe that sends and receives sound waves is placed gently on the surface of the eye. The echoes make a picture of the inside of the eye and the distance from the cornea to the retina is measured. The picture, called a sonogram, shows on the screen of the ultrasound monitor. The picture can be printed to be looked at later.
• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as the eye. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• CT scan (CAT scan): A procedure that makes a series of detailed pictures of areas inside the body, such as the eye, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show up more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• Bone scan: A procedure to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones and is detected by a scanner that also takes a picture of the body. Areas of bone with cancer show up brighter in the picture because they take up more radioactive material than normal bone cells do.

Retinoblastoma can usually be diagnosed without a biopsy.

When retinoblastoma is in one eye, it sometimes forms in the other eye. Exams of the unaffected eye are done until it is known if the retinoblastoma is the heritable form.

Signs and Symptoms

Signs and symptoms of retinoblastoma include “white pupil” and eye pain or redness.

These and other signs and symptoms may be caused by retinoblastoma or by other conditions. Check with a doctor if your child has any of the following:

• Pupil of the eye appears white instead of red when light shines into it. This may be seen in flash photographs of the child.
• Pain or redness in the eye.
• Eyeball is larger than normal.
• Colored part of the eye and pupil look cloudy.
• Eyes appear to be looking in different directions (lazy eye).

Treatment Options

There are different types of treatment for patients with retinoblastoma.

Different types of treatment are available for patients with retinoblastoma. Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.

Because cancer in children is rare, taking part in a clinical trial should be considered. Some clinical trials are open only to patients who have not started treatment.

Children with retinoblastoma should have their treatment planned by a team of health care providers who are experts in treating cancer in children.

The goals of treatment are to save the child’s life, to save vision and the eye, and to prevent serious side effects. Treatment will be overseen by a pediatric oncologist, a doctor who specializes in treating children with cancer. The pediatric oncologist works with other health care providers who are experts in treating children with eye cancer and who specialize in certain areas of medicine. These may include a pediatric ophthalmologist (children’s eye doctor) who has a lot of experience in treating retinoblastoma and the following specialists:

• Pediatric surgeon.
• Radiation oncologist.
• Pediatrician.
• Pediatric nurse specialist.
• Rehabilitation specialist.
• Psychologist.
• Social worker.
• Geneticist or genetic counselor.

Some cancer treatments cause side effects months or years after treatment has ended.

Side effects from cancer treatment that begin during or after treatment and continue for months or years are called late effects. Late effects of treatment for retinoblastoma may include the following:

• Physical problems such as seeing or hearing problems or, if the eye is removed, a change in the shape and size of the bone around the eye.
• Changes in mood, feelings, thinking, learning, or memory.
• Second cancers (new types of cancer), such as lung and bladder cancers, osteosarcoma, soft tissue sarcoma, or melanoma.

The following risk factors may increase the risk of having another cancer:

• Having the heritable form of retinoblastoma.
• Past treatment with radiation therapy, especially before age 1 year.
• Having a previous second cancer.

It is important to talk with your child’s doctors about the effects cancer treatment can have on your child. Regular follow-up by health professionals who are experts in diagnosing and treating late effects is important. See the PDQ summary on Late Effects of Treatment for Childhood Cancer for more information.

Six types of standard treatment are used:

Surgery (enucleation)

Enucleation is surgery to remove the eye and part of the optic nerve. The eye will be checked with a microscope to see if there are any signs that the cancer is likely to spread to other parts of the body. Enucleation is done if there is little or no chance that vision can be saved and when the tumor is large, did not respond to treatment, or comes back after treatment. The patient will be fitted for an artificial eye.

Close follow-up is needed for 2 years or more to check for signs of recurrence in the area around the affected eye and to check the other eye.

Radiation therapy

Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, plaques, or catheters that are placed directly into or near the cancer.

Methods of radiation therapy used to treat retinoblastoma include the following:

• Intensity-modulated radiation therapy (IMRT): A type of 3-dimensional (3-D) radiation therapy that uses a computer to make pictures of the size and shape of the tumor. Thin beams of radiation of different intensities (strengths) are aimed at the tumor from many angles. This type of radiation therapy causes less damage to healthy tissue near the tumor.
• Stereotactic radiation therapy: Radiation therapy that uses a rigid head frame attached to the skull to aim high-dose radiation beams directly at the tumors, causing less damage to nearby healthy tissue. This is also called stereotactic external-beam radiation and stereotaxic radiation therapy.
• Proton beam radiation therapy: Radiation therapy that uses protons made by a special machine. A proton is a type of high-energy radiation that is different from an x-ray.
• Plaque radiotherapy: Radioactive seeds are attached to one side of a disk, called a plaque, and placed directly on the outside wall of the eye near the tumor. The side of the plaque with the seeds on it faces the eyeball, aiming radiation at the tumor. The plaque helps protect other nearby tissue from the radiation.

The way the radiation therapy is given depends on how the cancer responded to other treatments and whether cancer has spread to other parts of the body.

Cryotherapy

Cryotherapy is a treatment that uses an instrument to freeze and destroy abnormal tissue. This type of treatment is also called cryosurgery.

Thermotherapy

Thermotherapy is the use of heat to destroy cancer cells. Thermotherapy may be given using a laser beam aimed through the dilated pupil or onto the outside of the eyeball. Thermotherapy may be used alone for small tumors or combined with chemotherapy for larger tumors. This treatment is a type of laser therapy.

Chemotherapy

Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. The way the chemotherapy is given depends on the stage of the cancer and where the cancer is in the body.

There are different types of chemotherapy:

• Systemic chemotherapy: When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body. Systemic chemotherapy is given to shrink the tumor (chemoreduction) and avoid surgery to remove the eye. After chemoreduction, other treatments may include radiation therapy, cryotherapy, laser therapy, or regional chemotherapy. Systemic chemotherapy may also be given to kill any cancer cells that are left after the initial treatment or to patients with retinoblastoma that occurs outside the eye. Treatment given after the initial treatment, to lower the risk that the cancer will come back, is called adjuvant therapy.
• Regional chemotherapy: When chemotherapy is placed directly into the cerebrospinal fluid (intrathecal chemotherapy), an organ (such as the eye), or a body cavity, the drugs mainly affect cancer cells in those areas. Several types of regional chemotherapy are used to treat retinoblastoma.
  • Ophthalmic artery infusion chemotherapy: Ophthalmic artery infusion chemotherapy carries anticancer drugs directly to the eye. A catheter is put into an artery that leads to the eye and the anticancer drug is given through the catheter. After the drug is given, a small balloon may be inserted into the artery to block it and keep most of the anticancer drug trapped near the tumor. This type of chemotherapy may be given as the initial treatment when the tumor is in one eye only or when the tumor has not responded to other types of treatment. Ophthalmic artery infusion chemotherapy is given at special retinoblastoma treatment centers.
  • Subtenon chemotherapy: Subtenon chemotherapy is the use of drugs injected through the membrane covering the muscles and nerves at the back of the eyeball. It is usually combined with systemic chemotherapy and local treatment (such as radiation therapy, cryotherapy, or thermotherapy) in order to avoid surgery to remove the eye.
  • Intravitreal chemotherapy: Intravitreal chemotherapy is being studied for the treatment of cancer that has spread to the vitreous (fluid) inside the eye. An anticancer drug is injected directly into the fluid in the eye.

See Drugs Approved for Retinoblastoma for more information.

High-dose chemotherapy with stem cell rescue

High-dose chemotherapy with stem cell rescue is a way of giving high doses of chemotherapy and replacing blood -forming cells destroyed by the cancer treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of the patient and are frozen and stored. After the chemotherapy is completed, the stored stem cells are thawed and given back to the patient through an infusion. These reinfused stem cells grow into (and restore) the body’s blood cells.

See Drugs Approved for Retinoblastoma for more information.

New types of treatment are being tested in clinical trials.

Information about clinical trials is available from the NCI website.

Patients may want to think about taking part in a clinical trial.

For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.

Many of today’s standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.

Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.

Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. See the Treatment Options section that follows for links to current treatment clinical trials. These have been retrieved from NCI’s listing of clinical trials.

Follow-up tests may be needed.

Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests.

Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your child’s condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.