Retinoblastoma

Retinoblastoma is genetic, which means that it is caused by mutations in a gene. These mutations prevent the body from making certain proteins that when working control how cells grow. When these proteins are not made correctly, too many cells can build up in one place and form a tumor.

While all retinoblastoma is genetic, only a proportion are hereditary.

About 70 to 75 percent of cases are nonhereditary, meaning that the mutation develops in the child and is not passed on to future generations. This is known as “sporadic retinoblastoma,” and usually only one eye is affected. Children with nonhereditary retinoblastoma tend to develop tumors later, and they do not have an increased risk of other tumors.

About 25 to 30% cases or retinoblastoma are hereditary. These children tend to develop tumors at a younger age and are more likely to have tumors in both eyes. Children with hereditary retinoblastoma are also at higher risk of developing other tumors, including childhood tumors in the brain, or osteosarcoma (a tumor of the bone), soft tissue sarcomas, or melanomas later in life.

To determine whether the retinoblastoma is hereditary, all children with retinoblastoma seen at Dana-Farber/Boston Children’s are referred to the Pediatric Cancer Genetic Risk Program, a comprehensive program that provides genetic testing and counseling. If hereditary retinoblastoma is identified, further screening recommendations and an invitation to enroll in screening studies may be offered. We also can provide testing of other family members through this program.

Retinoblastoma symptoms tend to develop before age 2. The most common symptoms include:

• leukocoria – the pupil of the eye appears white instead of the expected red when light shines into it. This effect is also often seen in photos that are taken with a flash. Rather than the typical “red eye,” the pupil may appear white or distorted. Leukocoria is the most common presenting symptom of retinoblastoma, but it is not required for a diagnosis.
• strabismus (also called “wandering eye” or “crossed eyes”) – one or both eyes don’t appear to be looking in the same direction
• nystagmus – involuntary movement of the eye(s)
• poor vision or change in vision
• (rarely) pain or redness around the eye(s)

Keep in mind that these symptoms can be caused by other conditions – for example, leukocoria and poor vision may be caused by a cataract – so it’s important to always see a specialist for a diagnosis.

The first step in treating your child is to obtain an accurate and complete diagnosis. In addition to a complete medical history and physical examination, your child’s doctor may order one or more tests to determine the cause of his or her symptoms. Most often, the tests are performed under general anesthesia, so your child won’t feel a thing. Tests include:

• Complete eye (fundoscopic) examination – While your child is under anesthesia, the doctor will dilate her pupils and look into the inside of her eye, including the retina and optic nerve.
• Magnetic resonance imaging (MRI) of the orbits and brain
• Ultrasound of the eye

If advanced disease is suspected, other work-up may be needed, including specialized imaging such as a bone scan, and studies such as a lumbar puncture and evaluation of the bone marrow. Retinoblastoma is usually diagnosed without a biopsy.

In addition to physical exam and imaging procedures, our genetic counselors from the Pediatric Cancer Genetic Risk Program will meet with you and discuss the possibility of taking a blood sample and running tests to look for an abnormal retinoblastoma gene. This allows us to have an informed discussion with you about whether the condition in your child’s case is heritable (as described above in the "causes" section).

Stages of retinoblastoma
During the workup for retinoblastoma, your child’s doctors will look to determine the size, number and location of the tumor or tumors, and whether they have spread to the other parts of the body. This is called staging, and is an important step in planning treatment. 

Your team will determine whether the retinoblastoma is intraocular (inside the eye) or extraocular (the cancer has also spread outside the eye).

Recurrent retinoblastoma refers to cases where the tumor comes back after treatment.

After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. Then we will meet with you and your family to discuss the results and to outline the best treatment options for your child. 

After your child is diagnosed with retinoblastoma, you may feel overwhelmed with information. It can be easy to lose track of the questions that occur to you. Lots of parents find it helpful to write down questions as they arise – that way, when you talk to your child’s doctors, you can be sure that all of your concerns are addressed.

Some of the questions you may want to ask include:

• Has my child’s tumor spread?
• Can my child’s retinoblastoma be treated with intra-arterial chemotherapy?
• What exactly does treatment involve, and will my child need to be in the hospital?
• What are the possible short and long-term complications of treatment? How will they be addressed?
• What is the chance that my child will be cured?
• What is the chance that my child’s vision will be spared?
• What happens if the tumor returns?
• What services are available to help my child and my family cope?

Coping and support

In addition to providing medical care, Dana-Farber/Boston Children’s strives to meet all of your family's emotional and quality-of-life needs. We know that unfamiliar places, especially hospitals, often create anxiety and fear for a child. We also know this is a difficult time for parents, who have their own fears and concerns about the situation. Our family support services will help address many of your needs and concerns.

We understand how difficult a diagnosis of retinoblastoma can be, both for your child and for your whole family. That's why our specialists are focused on family-centered care: from your first visit, you'll work with a team of professionals who are committed to supporting all of your family's physical and psychosocial needs. We'll work with you to create a care plan that's best for your child.

The good news is that since retinoblastoma is usually found before it spreads outside of the sclera (the outer white part of the eye), the condition is highly curable. Fortunately, there are several types of treatment that can save sight in the affected eye. These are described below:

Intra-arterial chemotherapy

Traditional forms of treatment for retinoblastoma carry the risk of injuring the eye (for example, when radiation is used) or of causing systemic symptoms, such as a weakened immune system (for example, when IV chemotherapy is used). For these reasons, our retinoblastoma treatment team will utilize intra-arterial chemotherapy whenever it is appropriate for a patient’s tumor. 

Intra-arterial chemotherapy is a relatively newer treatment for retinoblastoma in which the chemotherapy is injected directly into the main blood vessel of the eye (the ophthalmic artery). This treatment was designed to minimize the amount of contact the chemotherapy has with the rest of your child’s body, so as to reduce side effects. Even though the total dose of chemotherapy injected is lower than in traditional IV treatment, the dose delivered directly to the eye is much higher, and so may kill more cancer cells in fewer treatments. The eye is uniquely suited to intra-arterial chemotherapy because the blood supply to the eye, in almost all cases, travels through just one feeding artery.

During this procedure, your child is put to sleep by an anesthesiologist. Then the surgeon inserts a thin catheter through a blood vessel in your child’s groin, and feeds it up the arteries of the body to the ophthalmic artery. At this point, the chemotherapy is injected through the catheter directly to the eye. The average number of treatment sessions is three to four for each affected eye, delivered about every four weeks.

Because young children have smaller and more fragile arteries than adults, it is important that children who receive intra-arterial chemotherapy are treated at a pediatric-specific cancer center. At Dana-Farber/Boston Children’s, our interventional neuroradiologists have specialized expertise in working with children, including babies and toddlers, and our complication rates are the lowest published for comparable procedures performed at other centers, including both adult and pediatric centers.

Chemoreduction

With chemoreduction, chemotherapy is given through an IV. It passes through your child's blood stream, and if successful, causes the tumors to shrink within a few weeks. Depending on which drugs your doctor prescribes, your child may or may not be hospitalized during treatment. Chemoreduction rarely, if ever, cures retinoblastoma when used alone, so additionally treatments such as cryotherapy, thermotherapy, photocoagulation, or radiation also would be needed (see descriptions below).

Surgery

Surgery is usually reserved for children with advanced retinoblastoma that doesn't respond to other treatments. In these cases, the eye may need to be removed during a procedure called enucleation. While it is theoretically possible for the tumor to return even following this procedure, such cases would be extremely rare.

Enucleation is a relatively simple operation that is performed while your child is under general anesthesia. Following the surgery, the eye is replaced with an orbital implant, and after the eye has healed, an artificial eye – made to match your child's healthy eye – can be worn. Some newer types of implants allow the artificial eye to move, but implants are not yet able to provide vision. Children who have an artificial eye can still participate in sports, as long as they use proper protective eyewear.

Cryotherapy

Cryotherapy (sometimes called cryosurgery), applies extreme cold directly to the tumor and is used to treat small tumors or additional tumors that develop outside of the original tumor. Cryotherapy is often used together with chemotherapy, or it may be used after radiation therapy.

During cryotherapy, your child is first put to sleep by an anesthesiologist. Then the surgeon uses ultrasound to guide and place a small, extremely cold probe directly onto the tumor. The surgeon takes extreme care to ensure that the surrounding healthy tissue remains unharmed. Cryotherapy may be repeated on several occasions, if necessary.

An advantage of cryotherapy is that it may help prevent the need for enucleation or radiation therapy. The major disadvantages are that cryotherapy may leave a scar which damages future vision and that the procedure is not very effective in treating larger tumors.

Thermotherapy

Thermotherapy is a method of delivering heat to the eye using ultrasound, microwaves, or infrared radiation. Like cryotherapy, thermotherapy is only useful for very small tumors, and can be combined with chemotherapy or radiation therapy. Thermotherapy leaves a relatively small scar and tends to preserve more vision than cryotherapy.

Photocoagulation

Photocoagulation, also called light coagulation, is another method for treating small tumors. This technique uses focused light from a laser to destroy the tumor by destroying its blood supply. Photocoagulation is sometimes used in combination with chemotherapy.

Radiation

Radiation therapy is a cancer treatment that uses high-energy X-rays or other types of radiation to kill cancer cells.

Side effects

All treatment types have side effects associated with them. Your care team will discuss side effects and ways to manage them before your child begins treatment.

Dana-Farber/Boston Children’s also offers specialists who deliver complementary or alternative medicines. These treatments, which may help control pain and the side effects of therapy, include:

• acupuncture/acupressure
• therapeutic touch
• massage
• herbal supplements
• dietary recommendations

Talk to your child's team about whether complementary or alternative medicine might be a good option for your child.

New types of treatment are being tested through clinical trials. A clinical trial is a research study meant to help improve current treatments or to obtain information on new treatments. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may then become the standard treatment. We also have studies open to address how best to screen children with cancer predisposition syndromes including retinoblastoma.

Your team will discuss clinical trials with you if it is appropriate for your child’s care.

One hundred years ago, retinoblastoma was almost always fatal. Today, retinoblastoma has one of the highest cure rates of all childhood cancers – about 95 to 98 percent – with more than nine out of every 10 children surviving well into adulthood. Lifelong follow-up is crucial for children with hereditary retinoblastoma who are at risk of developing cancer elsewhere in the body later in life. All children who have received cancer-directed therapy should also be followed for late-effects of treatment. Through the David B. Perini, Jr. Quality of Life Clinic, childhood cancer survivors receive comprehensive follow-up evaluations from their cancer care team.