Retinoblastoma is a rare cancer of the retina of the eye. The retina is a group of special nerve cells sensitive to light located in the back of the eye. These light sensing cells are connected to the brain and optic nerve, which allows sight. Retinoblastoma is the most common tumor affecting the eye in children. It almost always occurs in children less than 5 years old, with most before age 2.

The cancer is caused by a change (mutation) in the RB1 gene. It may be a gene passed down from parents (inherited). Or it may be a gene change that happens by chance (sporadic).

In 1 out of 3 children with retinoblastoma, it's present at birth (congenital), and the gene change is in all cells in the body. This is known as hereditary retinoblastoma. In this form, the retinoblastoma usually affects both eyes. It also increases the risk of other cancers, such as sarcoma and melanoma.

In 2 out of 3 children with retinoblastoma, they have no increased risk for other cancers. In these cases, it often affects only one eye.

Symptoms may affect one or both eyes. Symptoms can occur a bit differently in each child. They can include:

• Leukocoria. This is an abnormal white reflection from the retina of the eye. The dark center part of the eye (pupil) actually looks white. This may only be seen during a doctor's exam or in a flash photo.
• Strabismus (lazy eye). This is when the eyes are misaligned. The eyes don't move together or look in the same direction.

Less common symptoms that occur when the cancer is advanced may include:

• Pain, redness, or swelling of one or both eyes
• Trouble seeing
• Bulging of the eye
• Different colored irises (colored area of the eye)

Most of the time, retinoblastoma has not spread (metastasized) to other areas of the body when it's diagnosed. If it has spread, other symptoms may include:

• Loss of appetite
• Weight loss
• Vomiting
• Headache
• Neurologic problems, such as weakness, numbness, and trouble with movement
• Lump (mass)

The symptoms of retinoblastoma can be like other health conditions. Make sure your child sees a doctor for a diagnosis.

Your child's doctor will ask about your child's health history and symptoms. They will examine your child and pay close attention to the eyes. The doctor will likely advise that your child see an eye specialist (ophthalmologist).

The ophthalmologist will check your child's eyes with special tools. Your child may need a dilated indirect ophthalmoscopic exam. Your child may be given anesthesia medicine to sleep through the exam.

Your child may need other tests, such as:

• Ocular ultrasound. This test uses sound waves to create images of the eyes.
• CT scan. A series of X-rays from different angles and a computer are used to make detailed images.
• MRI. Large powerful magnets, radio waves, and a computer are used to make detailed images.
• Blood tests. Your child's blood may be tested for signs of disease, and for genetic changes.

A child may be diagnosed with no symptoms. This may be the case if you have a family history of retinoblastoma. Your child may have eye exams often to check for signs of the cancer.

After a diagnosis of retinoblastoma, these tests will help your child's doctor know if the cancer is inside the eye, how much of the eye is involved, and if it has spread beyond the eye. This process is called staging. The stage of a cancer is one of the most important things to know when deciding how to treat it.

First, doctors determine if the retinoblastoma is intraocular or extraocular. Intraocular is cancer that is in one or both eyes. It hasn't spread to other tissues or parts of the body. Extraocular is cancer that spread to tissues around the eye or other parts of the body.

If the cancer is intraocular, doctors use two standard staging systems for retinoblastoma:

• The newer system is called the International Classification for Intraocular Retinoblastoma. It divides these tumors into five groups lettered A through E. The groups are based on how likely it is that the eye can be saved. Group A means the tumor is small and not near important structures that allow your child to see. These tumors can likely be removed and vision can be saved. The higher the group, the more advanced the tumor is. A tumor in Group E means that doctors have little to no chance of saving the eye. The other groups then fall between these extremes.
• The Reese-Ellsworth system is older and less commonly used. It groups intraocular retinoblastomas much like the International Classification system, based on whether the eye and vision can be saved. The system uses groups numbered 1 through 5. Group 1 means a good chance of saving the eye, and Group 5 means it's not likely. The other groups fall between this.

Extraocular staging is used for retinoblastoma that has spread outside of the eyes. Spreading may occur to local tissue around the eye, to the central nervous system, the bone marrow, or lymph nodes. The stages are Stage 1 to Stage IV.

Doctors may use other staging systems, such as the American Joint Commission on Cancer staging system. The staging process for retinoblastoma can be very complex. Be sure to ask your child's doctor to explain the stage of your child's cancer.

Most children in the U.S. with retinoblastoma have a good chance of recovery.

Your child will be treated by a team of different types of doctors, such as:

• Ophthalmologist
• Pediatrician
• Pediatric surgeon
• Children's cancer specialist (pediatric oncologist)
• Retina specialist
• Specialist in using radiation therapy to treat cancer (radiation oncologist)
• Rehabilitation specialist
• Pediatric nurse specialist

Treatment will depend on your child's symptoms, age, and general health. It will also depend on how bad the condition is. It also depends on whether the retinoblastoma is hereditary.

Many of the treatment methods need sleep medicine (anesthesia). Treatment may include the following:

• Laser therapy or photocoagulation. A laser is used to destroy the blood supply to the tumor. This is used on some smaller tumors.
• Surgery. In some cases, surgery may be done to remove the eye. This is called enucleation. This is not needed for all retinoblastomas. They eye socket and eye are replaced with an implant and artificial eye.
• Chemotherapy. Anticancer medicines may be given into a vein (I.V.), by mouth, or directly into an artery that feeds the eye. The medicines may reduce the size of the tumor so that other treatments can work better.
• Radiation therapy. Radiation may be used when another treatment doesn't work well enough. Internal radiation (brachytherapy) may be done. A small container (plaque) with radioactive material is placed on the eye near the tumor. The plaque is placed and removed during surgery. This may be used to treat some smaller tumors.
• Thermotherapy. Laser light is used to destroy cancer cells using heat. This may be used for some small tumors. Or, it may be used with chemotherapy or radiation for larger tumors.
• Cryotherapy. A tool is used to freeze and kill the cancer cells.
• Bone marrow or stem cell transplantation. This treatment is used for children with stage IV extraocular retinoblastoma after high doses of chemotherapy, radiation therapy, or both.
• Supportive care. Treatment can cause side effects. Medicines and other treatments can be used for pain, fever, infection, and nausea and vomiting.
• Clinical trials. Ask your child's doctor if there are any treatments being tested that may work well for your child.

With any cancer, how well a child is expected to recover (prognosis) varies. Keep in mind:

• Getting medical treatment right away is important for the best prognosis. Cancer that has spread may involve much more treatment.
• Ongoing follow-up care during and after treatment is needed.
• New treatments are being tested to improve outcome and to reduce side effects.

A child may have complications from the cancer or from treatment, such as:

• Detached retina
• Spreading of the cancer (metastasis)
• Loss of eyesight
• Side effects of chemotherapy, such as tiredness, bruising and bleeding, mouth sores, infections, vomiting, and diarrhea
• Bleeding or infection from surgery
• Growth of other cancers

You can help your child manage their treatment in many ways. For example:

• Your child may have trouble eating. A dietitian may be able to help.
• Your child may be very tired. They will need to balance rest and activity. Encourage your child to get some exercise. This is good for overall health. And it may help to reduce tiredness.
• Get emotional support for your child. Find a counselor or child support group.
• Make sure your child attends all follow-up appointments.

A child with retinoblastoma needs ongoing care. Your child will be cared for by a team of doctors. They will treat any late effects of treatment and watch for signs or symptoms of the tumor growing back. The doctors will also keep track of your child with imaging and other types of tests.

Note: If your child has an implant and artificial eye, they should wear protective eyewear during activities that may harm the eye.

Family members may want to see a genetic counselor to learn more about the risk for retinoblastoma.

Contact the doctor or get medical help right away if your child has:

• Symptoms that get worse
• New symptoms
• Side effects from treatment

• Retinoblastoma is a rare cancer of the retina of the eye. The retina is a specialized group of nerve cells located in the back of the eye. These light sensing cells are connected to the brain and optic nerve which allows sight.
• The cancer may be passed on from parents (inherited) or it may occur by chance (sporadic).
• The most common symptoms are an abnormal white reflection from the retina (leukocoria) and misaligned eyes (strabismus).
• It's diagnosed by a dilated indirect ophthalmoscopic exam.
• In the U.S., the prognosis for most children with retinoblastoma is very good.
• There are many treatments for retinoblastoma, including surgery, chemotherapy, radiation therapy, laser therapy, and cryotherapy.

Tips to help you get the most from a visit to your child's doctor:

• Know the reason for the visit and what you want to happen.
• Before your visit, write down questions you want answered.
• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you for your child.
• Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
• Ask if your child's condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if your child does not take the medicine or have the test or procedure.
• If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your child's doctor after office hours and on weekends and holidays. This is important if your child becomes ill and you have questions or need advice.