What’s New in Retinoblastoma Research and Treatment?



Genetics, genetic counseling, and gene therapy




Recently, researchers have found that a very small portion of retinoblastomas don’t seem to have changes in the RB1 gene, but instead have too many copies of another gene called MYCN. It is not yet clear if these cancers are different in any important ways from those with RB1 gene changes.



Radiation therapy

External radiation therapy can be used to treat retinoblastoma, but it can cause side effects because the radiation often reaches nearby tissues as well. Newer forms of radiation therapy such as intensity modulated radiation therapy (IMRT) and proton beam therapy can better target the tumor and spare nearby normal tissues. These techniques, which are described in the section “ Radiation therapy for retinoblastoma,” may help doctors limit the side effects from radiation therapy.

Other local treatments

Doctors continue to improve the instruments used for cryotherapy, laser therapy (photocoagulation), thermotherapy, and other local treatments. The goal is to kill tumor cells more precisely while sparing other parts of the eye.



Systemic chemotherapy


Localized chemotherapy

Chemo can help shrink most retinoblastomas, but when it’s given into the bloodstream it can cause side effects in different parts of the body. This limits the doses that can be given. Newer techniques help keep the chemo concentrated in the areas around the tumors. This can help doctors get higher doses of chemo to the tumors while reducing some of these side effects. Some of these techniques are described in the section “ Chemotherapy for retinoblastoma.”

Intra-arterial chemotherapy: In this approach, chemo is injected directly into the ophthalmic artery, the main artery feeding the eye, using a long, thin catheter. When intra-arterial chemotherapy is used, the dose of the chemo drug is much lower than when it is given by vein, and the side effects related to the chemo are minimal.

Intravitreal chemotherapy: Some doctors are studying injecting chemotherapy directly into the jelly-like fluid inside the eyeball (the vitreous humor) to treat tumors that are widespread within the eye and not helped by other treatments. The main concern with this technique is that placing the needle into the eye to give the chemo might open a small hole that could allow tumor cells to spread outside of the eye, so doctors are being very cautious with this approach. Some doctors are studying the use of cryotherapy (using very cold temperatures) at the site of injection to limit this risk. Intravitreal chemotherapy is still in the early stages of testing.

The American Cancer Society medical and editorial content team

