Pediatric Oncology Program

Patient and Family Education

Retinoblastoma

Stages and Treatment

If a child is diagnosed with retinoblastoma, the doctor will order more tests to determine the size of the tumor and whether it has spread to surrounding tissue or to other parts of the body. This process, called staging, helps the child's doctor to plan treatment.

Numerous imaging tests can be done to look for evidence of cancer in internal tissues. Spinal fluid and bone marrow may also be sampled to look for cancer cells in the brain and bone.

Although there are several staging systems currently available for retinoblastoma, for the purposes of treatment it may be most useful to categorize the disease as either intraocular (within the eyes) and extraocular (extending beyond the eyes).

Intraocular retinoblastoma: Cancer is found in one or in both eyes but does not extend into the tissues around the eye or to other parts of the body. Treatment depends on whether the cancer is in one or both eyes.

If the cancer is in one eye, treatment may be one of the following:

External radiation therapy, photocoagulation, cryotherapy, or brachytherapy may be used with small tumors when there is potential for preservation of sight.
Surgery to remove the eye (enucleation) is used for large tumors when there is no expectation that useful vision can be preserved.

If the cancer is in both eyes, treatment may be one of the following:

Surgery to remove the eye with the most cancer and/or radiation therapy to the other eye.
Radiation therapy to both eyes if there is potential for vision in both eyes.
Clinical trials testing systemic chemotherapy with or without other types of treatment

Extraocular retinoblastoma: The cancer extends beyond the eye. It may be confined to the tissues around the eye, or it may have spread to other parts of the body. Treatment may be one of the following:

Radiation therapy and/or intrathecal (into the space between the lining of the spinal cord and the brain) chemotherapy .
Clinical trials testing new combinations of chemotherapy drugs, with or without peripheral stem cell transplantation, and different ways of administrating chemotherapy drugs.

Recurrent retinoblastoma: Recurrent disease is cancer that has come back (recurred) or progressed (continued to grow) after it has been treated. It may recur in the eye, the tissues around the eye, or elsewhere in the body.

Treatment depends on the site and extent of the recurrence (or progression). If the cancer comes back only in the eye and is small, the child may have surgery or radiation therapy. If the cancer comes back outside of the eye, the child may receive chemotherapy. Parents may want to consider having their child participate in a clinical trial.

About the Treatments and Side Effects

There are four primary treatments for children with retinoblastoma: enucleation, radiation therapy, cryotherapy, and photocoagulation. A fifth treatment, chemotherapy, is being tested in clinical trials.

The type of treatment chosen depends on the extent of the disease within the eye, how good the childs vision is in each eye, whether the disease is in one or both eyes, and whether the disease has spread beyond the eye:

Enucleation

If a child has a tumor in only one eye and has already lost vision, doctors will typically remove the eye in a surgical procedure called enucleation. Enucleation is a simple and fairly short operation, and the child can often go home the same day.

An artificial eye can be created to match the childs other eye. In addition to the loss of vision, the removal of the eye will affect the tissue and bone around the eye socket, so that the eye may look sunken.

If the child has tumors in both eyes and has already lost vision in both eyes, the doctors will probably want to remove the eyes, particularly if the cancer might spread. However, if there is any vision in either eye and any possibility of saving it, every attempt will be made to preserve it by using chemotherapy or radiation therapy.

Radiation Therapy

Radiation therapy is the use of high-energy x-rays to kill cancer cells and shrink tumors. If a child still has vision in the eye that has the tumor, radiation therapy may destroy or control the cancer and preserve the childs eyesight.

There are two types of radiation therapy: external beam radiation and internal radiation therapy (or brachytherapy).

During external beam radiation, the child is given medication to make him or her sleep. The childs head is placed in a custom-fitted mold to keep it still while radiation beams from an outside source are directed at the cancer. It is very important that the child does not move, so that the radiation beams can target the cancer and do not damage the surrounding tissue. The treatments are given daily over the course of a few weeks.

Internal radiation therapy (brachytherapy) is given in the form of tiny radioactive seeds, which are placed temporarily in the eye socket and then removed a few days later. The procedure allows a higher dose of radiation to be delivered to the tumor than can be delivered by external beam radiation. The child is under general anesthesia so that he or she is sleeping during the procedure.

The most common side effects of radiation therapy are tiredness, skin reactions in the treated areas, and loss of appetite. Radiation for retinoblastoma has the potential to damage healthy eye tissue along with the cancerous tissue, which may result in cataracts, damage to the retina, and possible problems with the growth of bone and tissues surrounding the eye.

Cryotherapy

Cryotherapy is the use of extreme cold to freeze and destroy cancer cells. It is usually only used on very small tumors. An instrument that has been cooled to an extremely cold temperature is placed next to the tumor to kill the cancer. The procedure usually has to be repeated several times.

Photocoagulation

Photocoagulation (or laser therapy) is the use of a tiny beam of light, usually from a laser, to destroy blood vessels that supply nutrients to the tumor. For retinoblastoma, the laser is aimed through the pupil or the side of the eyeball while the child is under general anesthesia.

Chemotherapy

Chemotherapy is the use of drugs to kill cancer cells. Most anticancer drugs are injected into a vein or a muscle, but some are given by mouth. Chemotherapy is a systemic treatment, meaning that the drugs flow through the bloodstream to nearly every part of the body to kill cancerous cells. It is generally given in cycles: a treatment period is followed by a recovery period, then another treatment period, and so on.

For retinoblastoma, chemotherapy is sometimes used to shrink tumors before they are treated with another type of therapy. It is also used to control the spread of cancer cells outside the eye, although this approach seems to be only temporarily effective. The tumors shrink for a while but begin to grow again after several months.

Chemotherapy drugs generally fight rapidly dividing cells in the body. Cells that divide rapidly include both the targeted cancer cells and healthy cells in the blood, digestive tract, and hair follicles.

Depending on which anticancer drugs a patient receives, he or she may experience symptoms when healthy cells are damaged along with the cancer cells.

If healthy blood cells are destroyed by chemotherapy, the patient may be more susceptible to infections, bruising or bleeding, and fatigue. When cells in the hair roots or digestive tract are affected by anticancer drugs, the patient may have hair loss, nausea, vomiting, or mouth sores.

Not all chemotherapy patients develop all ofthese side effects, and the symptoms usually go away during the recovery period or after the treatments are done. Doctors can prescribe medicines and other treatments to control most of the symptoms.

This page was last updated on: October 20, 2009.