Treating Retinoblastoma

For smaller tumors, focal treatments such as laser therapy or cryotherapy aimed at the tumor directly might be the only treatment needed.

But more often, tumors are larger or in hard-to-treat areas. Treatment usually includes a combination of chemotherapy and focal treatments.

If systemic chemotherapy (chemotherapy given by vein) is used, it is typically given for a few months to shrink the tumor as much as possible. More recently, many centers have begun to give chemotherapy directly into the artery that feeds the eye (known as intraarterial chemotherapy) instead of systemic chemotherapy. If the cancer has spread widely inside the eye, chemo might also be injected directly into the eye (known as intravitreal chemotherapy). Usually a few treatments are needed, each given a few weeks apart. Intraarterial and intravitreal chemo are given with anesthesia, or medicines to help a child relax and sleep during the treatment.

Depending on how much the tumor shrinks and where it is in the eye, different focal treatments can then be used. Treatment options might include brachytherapy (plaque radiotherapy), cryotherapy, or laser therapy (photocoagulation or thermotherapy). External radiation therapy might also be given, but if so, it is usually delayed until the end of chemotherapy.

If the combination of these treatments does not control the disease, the eye might need to be removed.

If there is no vision in the eye, if the tumor is so advanced within the eye that there is no hope of cure by other means, or if there is painful glaucoma (increased pressure inside the eye), then the eye is removed and an orbital implant is placed in the socket. This procedure is called enucleation.

If the cancer affects only one eye, no other treatments may be needed. But sometimes, after looking at the removed eye under the microscope, the doctors find that some retinoblastoma cells might have spread, which means the cancer might come back later in other parts of the body. These children may be given chemotherapy, possibly along with radiation therapy to the area around the eye, to try to lower this risk.

In some instances where there are large tumors in both eyes, chemo may be used first to try to shrink the tumors and avoid the need for surgery in both eyes. If chemo shrinks the tumors enough, focal therapies such as brachytherapy (plaque radiotherapy), cryotherapy, or laser therapy (photocoagulation or thermotherapy) might allow at least one eye (and some vision) to be saved.

Some children with retinoblastoma in only one eye may actually have the hereditary form of retinoblastoma, which means they have a high chance of having cancer in the other eye as well. Therefore, it is very important to consider genetic counseling and testing to determine if the child has hereditary retinoblastoma. If so, they need to have the other eye examined regularly after treatment.

In this situation, treatment is usually a combination of chemotherapy, radiation, and in some cases surgery.

If the cancer has spread only to the orbit (the area around the eye), treatment with chemotherapy, surgical removal (enucleation) of the eye, and radiation therapy to the orbit is often successful.

If the cancer has spread outside the orbit to distant parts of the body such as the liver, bones, and bone marrow, the chances of a cure using standard chemotherapy and other treatments are not as good. In these cases, using higher doses of chemotherapy followed by a stem cell transplant may be recommended.

Retinoblastomas with tumors in the brain (trilateral retinoblastoma) are very hard to treat. These tumors may be treated with chemotherapy and radiation. Experimental high-dose chemotherapy with stem cell transplant has shown some promise for these cancers. Clinical trials using other newer treatments may be an option in this situation as well.

Treatment of cancer that recurs in the eye depends on the size and location of the tumor and on what treatments were used the first time.

If the tumor is small, the child’s sight can often be saved and the cancer destroyed with local treatments such as cryotherapy, laser therapy, radiation therapy (if not already used), or other treatments. Chemotherapy might be given first to shrink the tumor, which might help the other treatments work better.

If the child’s sight cannot be saved, surgery to remove the eye may be recommended.

Either way, the chance of a cure is good as long as the cancer has not spread outside the eye.

Cancers that recur outside the eye are harder to treat. Options might include chemotherapy and radiation, or high-dose chemotherapy with a stem cell transplant in some cases.