Hereditary Retinoblastoma

Retinoblastoma is caused by a change (mutation) in the RB1 gene. This gene change may be inherited from a parent or occur by chance (sporadically).

About 1 in 3 children with retinoblastoma have the hereditary form, in which the RB1 gene change is present at birth and found in all of the body's cells. Hereditary retinoblastoma often affects both eyes, although it can also present as multiple tumors in one eye. Children with the hereditary form have an increased risk of developing additional retinoblastomas and other cancers later in life, including sarcoma and melanoma. Nearly all children with tumors in both eyes have the hereditary form.

About 2 in 3 children with retinoblastoma do not have the hereditary form. In these cases, the gene change occurs only in the retinal cells, usually affects one eye, and does not significantly increase the risk of developing other cancers. Most children with a single tumor in one eye have this non-hereditary form, although a small percentage may still have hereditary retinoblastoma. The chance of a child having the hereditary form depends on how the disease presents and may be determined through genetic testing.

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 may include:

• Pain, redness or swelling of one or both eyes
• Trouble seeing
• Bulging 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 healthcare provider for a diagnosis.

Your child's healthcare provider will ask about your child's health history and symptoms. They will examine your child and pay close attention to the eyes. Your healthcare provider 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 and a computer are used to make detailed images.
  
• MRI. Large 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.

Your 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 healthcare provider 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. 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 healthcare providers 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 retinoblastomas much like the International Classification system, based on whether the eye and vision can be saved. The system uses groups numbered one through five. Group one means a good chance of saving the eye, and Group five means it's not likely. The other groups fall between this.

Doctors may use other staging systems. The staging process for retinoblastoma can be very complex. Be sure to ask your child's healthcare provider 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 healthcare providers, such as:

• Ophthalmologist
• Pediatrician
• Pediatric Surgeon
• Children’s cancer specialist (pediatric oncologist)
• Retina specialist
• Specialist in using radiation 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 severe the condition is. It also depends on whether the retinoblastoma is hereditary.

Many of the treatment methods require 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. Anti-cancer medicines may be given into a vein (IV), by mouth (systemic), 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. 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.
• 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 healthcare provider 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 lessen side effects.

Yes. Having hereditary retinoblastoma increases the chance of developing a second retinoblastoma and other tumors outside the eye, including:

• Pineoblastoma (a tumor in the pineal gland in the brain)
• Osteosarcoma (a type of cancer originating in the bones)
• Soft tissue sarcoma (a type of cancer originating in soft tissues of the body such as muscles, tendons and nerves)
• Melanoma (a type of skin cancer)

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